JP2013209333A - Filter for removing leukocyte and abnormal prion, and method for removing leukocyte and abnormal prion using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for removing leukocyte and abnormal prion capable of efficiently removing the leukocyte from a blood preparation, removing abnormal prion simultaneously, and maintaining blood preparation quality after filtration and storage.SOLUTION: A coating agent includes a polymer comprising a unit derived from a polymerizable monomer including a basic nitrogen-containing fragment, a unit derived from a hydrophobic polymerizable monomer, and a unit derived from a polymerizable monomer containing a protonic neutral hydrophilic fragment, wherein the molar fraction of the unit derived from the polymerizable monomer including the basic nitrogen-containing fragment is 3 mol% or more and 5 mol% or less, and the molar fraction of the unit derived from the hydrophobic polymerizable monomer with respect to the unit derived from the polymerizable monomer containing the protonic neutral hydrophilic fragment is 0.52-0.67. The coating agent adsorbs leukocyte and abnormal prion.

Description

  The present invention relates to a leukocyte and abnormal prion removal filter, and a leukocyte and abnormal prion removal method using the same. More specifically, the present invention relates to a removal filter that can remove undesirable components such as aggregates, leukocytes, and abnormal prions from a blood product, and can maintain the quality of the product after filtration storage.

At present, in the field of blood transfusion, so-called leukocyte-removed blood transfusion is performed widely, in which a mixed leukocyte contained in a blood product is removed for transfusion. This includes side effects such as headaches, nausea, chills, non-hemolytic fever reactions associated with blood transfusions, alloantigen sensitization that has a more serious effect on recipients, post-transfusion graft-versus-host disease (GVHD), viral infections This is because the serious side effects were caused mainly by leukocytes mixed in blood products used for blood transfusion. In the method of removing leukocytes from a blood product, the filter method is widely used because of its high leukocyte removal ability, simple operation, and low cost. In recent years, the filtration method, that is, the treatment of blood products and the like by a leukocyte removal filter, is being generally performed at a blood center before storage in order to thoroughly control the quality of the leukocyte removal blood product. Normally, when filtering blood using a leukocyte removal filter at a blood center, place the blood bag containing the blood product to be filtered in a position 70 to 150 cm higher than the bag for collecting the filtered blood product. It is common practice to filter blood products by the action of gravity.
In order to prevent the above-mentioned serious side effects, a leukocyte removal filter that maintains the blood product quality after storage and is excellent in leukocyte removal ability is desired.

  On the other hand, recently, it was pointed out that the mutant CJD generated mainly in the UK is the result of beef consumption from cattle infected with BSE (Non-Patent Documents 1 to 3). In addition to the transmission of beef from cattle to humans due to consumption of beef, it is suggested that mutant CJD may be transmitted from humans to humans by transfusion of blood products and transmission of mutant prion protein present in tissue grafts. I came. In this situation, two cases were reported in which recipients who received blood from a donor who developed mutant CJD after donation in 2004 were infected with mutant CJD. In 2006, the third case was reported. The reported possibility of transmission of mutant CJD by blood transfusion has increased. In addition, there are a large number of infected humans who have not yet developed mutant CJD, and it has been pointed out that blood products from these humans may spread the infection. Therefore, a method is needed to remove abnormal prions from blood products.

  Transmissible spongiform encephalopathy (TSE), or prion disease, causes fatal neurodegenerative diseases in humans and other mammalian species. In particular, scrapie in sheep and BSE in cattle are widely known. The forms of human disease include sporadic Creutzfeldt-Jakob disease (sCJD), iatrogenic Creutzfeldt-Jakob disease, Gerstmann-Straeussler-Scheinker (GSS) syndrome, lethal familial isomnia (FFI) ) And Kuru. In prion diseases, normal normal prions naturally undergo structural changes and are converted into mutant abnormal prions (mutant prion proteins that cause prion diseases), which infect humans and other mammals. It has been. A mutant prion protein has a β-sheet-rich structure as compared with a normal prion protein, and thus has high hydrophobicity, easily forms a multimer, and is resistant to protease K.

  As a method for removing leukocytes and the like from a blood product, for example, Patent Document 1 includes a unit derived from a hydrophobic polymerizable monomer, a unit derived from a polymerizable monomer containing a basic nitrogen-containing portion, and a protic neutral hydrophilic portion. A leukocyte removal filter material coating polymer composed of units derived from a polymerizable monomer is disclosed. Patent Document 2 discloses three units which are a unit derived from a hydrophobic polymerizable monomer, a unit derived from a polymerizable monomer containing a basic nitrogen-containing moiety, and a unit derived from a polymerizable monomer containing a protic neutral hydrophilic moiety. A method of simultaneously removing abnormal prions and leukocytes from a blood product, characterized in that the blood product is filtered with a filter filled with a polymer-coated carrier composed of the following, and the blood product is recovered.

International Publication No. 03/011924 International Publication No. 08/007465

G. Chazot, et al. , (1996) Lancet 347: 1181 R. G. Will, et al. (1996) Lancet 347: 921-25. Guide to the preparation, use and quality assistance of blood components 9th edition / Council of Europe Publishing

  In the method of removing leukocytes and the like from the blood product, it is preferable that the operability, cost, blood loss amount, etc. in the blood center are equal to or higher than those of the prior art and that the quality of the blood product is maintained after storage. Furthermore, it is preferable that abnormal prions can be removed simultaneously in order to ensure the safety of blood products.

  In Patent Document 1, the polymer described in Patent Document 1 is described as a material having a high leukocyte removal ability, but there is no description or suggestion regarding the removal of abnormal prions and the quality of the preparation after storage. Patent Document 2 describes that the method described in Patent Document 2 provides a high-quality blood product with good blood product flowability and less hemolysis. However, in Patent Document 2, only hemolysis is evaluated with respect to the preparation quality after storage of the preparation after filtration, and there is no description or suggestion about generation of fine particles in the preparation.

  An object of the present invention is to provide a method for removing leukocytes and abnormal prions that can efficiently remove leukocytes from a blood product, simultaneously remove abnormal prions, and maintain blood product quality after filtration storage.

  The present inventors are not a polymer comprising a hydrophobic polymerizable monomer, a polymerizable monomer containing a basic nitrogen-containing moiety, or a polymerizable monomer containing a protic neutral hydrophilic moiety, but a terpolymer of these. As a result of extensive research using a polymer-coated filter, a predetermined amount of a polymerizable monomer containing a basic nitrogen-containing moiety is included, and a hydrophobic polymerizable monomer and a polymerizable monomer containing a protic neutral hydrophilic moiety are included. When the ratio is within a predetermined range, leukocytes can be removed from the blood product with high efficiency, the blood product quality after storage can be maintained, abnormal prions can be removed at the same time as the leukocytes, and poor performance due to poor filter priming is prevented. The present inventors have found that it is possible to obtain the present invention.

That is, the present invention relates to the following.
[1] A method for removing leukocytes and abnormal prions in a blood product, comprising the step of passing the blood product through a removal filter,
The removal filter comprises a container having an inlet and an outlet for blood, and a carrier filled in the container,
The carrier has a base material and a coating agent fixed to the surface of the base material,
The coating agent comprises a unit derived from a polymerizable monomer containing a basic nitrogen-containing moiety, a unit derived from a hydrophobic polymerizable monomer, and a unit derived from a polymerizable monomer containing a protonic neutral hydrophilic moiety. Hydrophobic polymerization of a unit derived from a polymerizable monomer containing a basic nitrogen-containing moiety and having a molar fraction of 3 mol% or more and 5 mol% or less and containing a protonic neutral hydrophilic moiety The removal method which consists of a polymer whose molar ratio of the unit derived from a sex monomer is 0.52-0.67.
[2] The removal method according to [1], wherein the number of fine particles generated in the blood product after storage for 42 days after filtration is 200 or less.
[3] When the blood product is filtered,
The removal method according to [1] or [2], wherein the leukocyte removal performance is 4 Log or more, the abnormal prion removal performance is 3 Log or more, and the number of fine particles generated in the blood product after filtration is 200 or less.
[4] The removal method according to any one of [1] to [3], wherein the polymer is a vinyl polymer.
[5] The hydrophobic polymerizable monomer, the polymerizable monomer containing a basic nitrogen-containing moiety, and the polymerizable monomer containing a protic neutral hydrophilic moiety are all acrylic acid derivatives or methacrylic acid derivatives. ] To [4].
[6] The removal method according to any one of [1] to [5], wherein the basic nitrogen-containing moiety is a tertiary amino group.
[7] The removal method according to any one of [1] to [6], wherein the protonic neutral hydrophilic portion is a hydroxyl group.
[8] The base material is a fibrous medium,
The removal method according to any one of [1] to [7], wherein a packing density of the carrier in the container is 0.1 g / cm ³ or more and 0.5 g / cm ³ or less.
[9] The removal method according to any one of [1] to [8], wherein the substrate is a fibrous medium or a sponge-like structure.
[10] The removal method according to any one of [1] to [9], wherein the substrate has a specific surface area of 1.0 m ² / g or more and 5.0 m ² / g or less.
[11] The removal method according to any one of [1] to [10], wherein the average pore diameter of the substrate is 1 μm or more and 60 μm or less.
[12] The removal method according to any one of [1] to [11], wherein the porosity of the substrate is 65% or more and 90% or less.
[13] The removal method according to any one of [1] to [12], wherein the substrate is a nonwoven fabric.
[14] The removal method according to any one of [1] to [13], wherein the nonwoven fabric has an average fiber diameter of 0.3 μm or more and 3.0 μm or less.
[15] A leukocyte and abnormal prion removal filter used in the removal method according to any one of [1] to [14].
[16] A carrier used in the removing method according to any one of [1] to [14].
[17] A coating agent that adsorbs leukocytes and abnormal prions used in the removal method according to any one of [1] to [14].

  According to the present invention, leukocytes can be removed from a blood product with high efficiency, and the blood product quality after storage can be maintained. Furthermore, it has become possible to obtain a blood product from which abnormal prions have also been removed.

1 is a schematic diagram showing a blood product filtration system according to an embodiment. FIG.

[Coating agent]
The coating agent for adsorbing leukocytes and abnormal prions of the present invention is made of a predetermined polymer. The polymer is also referred to as a polymerizable monomer containing a unit derived from a hydrophobic polymerizable monomer (also referred to herein as “hydrophobic monomer”) and a basic nitrogen-containing moiety (herein also referred to as “basic monomer”). ) A polymerizable monomer containing a unit derived from and a protic neutral hydrophilic portion, also referred to as “hydrophilic monomer” in the present specification. ) Origin unit.

In the present specification, the “unit” means a repeating minimum unit derived from each polymerizable monomer. The unit is illustrated. When the polymerizable monomer is a vinyl compound represented by CH ₂ = CXY (X: H or a substituent other than H, Y: a substituent other than X), and a double bond is simply opened, a unit is added. Is — (CH ₂ —CXY) — which is the minimum repeating unit. When the polymerizable monomer is A- (R) -B (R: a portion not desorbed by polymerization, A and B: a portion desorbed by polymerization), when the polycondensation occurs, the unit is polymerized by AB desorbing It is-(R)-which becomes the repeating minimum unit.

  The hydrophobic polymerizable monomer is a monomer having a very low affinity for water and does not contain a basic nitrogen-containing moiety or a protonic neutral hydrophilic moiety in the molecule.

  As the hydrophobic polymerizable monomer, specifically, from the viewpoint of easy availability and handling, styrene, methylstyrene, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, phenyl acrylate, Phenyl methacrylate, ethyl hexyl acrylate, ethyl hexyl methacrylate, trichloroethyl acrylate, trichloroethyl methacrylate, and other acrylates or methacrylates, alkenes such as pentene, hexene, heptene, octene, organosilicon compounds such as silicone siloxane, ethylene An organic fluorine-polymerizable monomer in which one or more hydrogen atoms are replaced with fluorine atoms can be exemplified. It is not limited to these. Among them, a monomer having a vinyl group as the polymerizable moiety from which a vinyl polymer can be obtained by addition polymerization (vinyl polymerization) is preferable because of easy availability of the monomer and easy handling. Among these, acrylic acid derivatives or methacrylic acid derivatives are more preferable as the hydrophobic polymerizable monomer. Most preferred as the hydrophobic polymerizable monomer is acrylate or methacrylate.

  A material having a basic nitrogen-containing functional group has a positive charge on the surface of the material in a physiological liquid, and can adhere leukocytes having a negative charge. Moreover, the effect which improves the removal performance of abnormal prion is also shown. The polymerizable monomer containing a basic nitrogen-containing moiety refers to a polymerizable monomer having a basic nitrogen-containing moiety described below.

  Basic nitrogen-containing moieties include functional groups such as primary amino groups, secondary amino groups, tertiary amino groups and quaternary amino groups, and nitrogen-containing aromatic groups such as pyridyl groups and imidazolyl groups. It can be illustrated. As the basic nitrogen-containing moiety, a tertiary amino group is particularly preferable.

  Specifically, as a polymerizable monomer containing a basic nitrogen-containing moiety, vinylamine, 2-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 4 from the viewpoint of easy availability and handling. -Vinyl derivatives of nitrogen-containing aromatic ring compounds such as vinylimidazole, N-vinyl-2-ethylimidazole, N-vinyl-2-methylimidazole, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl Methacrylates, acrylates and methacrylates such as 3-dimethylamino-2-hydroxypropyl acrylate and 3-dimethylamino-2-hydroxypropyl methacrylate, N, N-dimethylaminoethylacrylic acid amide, N-dimethylamino Acrylic acid amides and methacrylic acid amide derivatives such as ethylmethacrylic acid amide, N, N-diethylaminoethylacrylic acid amide, N, N-diethylaminoethylmethacrylic acid amide, N, N-dimethylaminopropylacrylic acid amide, p -Styrene derivatives such as dimethylaminomethyl styrene and p-diethylaminoethyl styrene, and derivatives in which the polymerizable monomer is a quaternary ammonium salt with a halogenated alkyl group. It is not limited to these. Among them, a monomer in which a polymerizable moiety from which a vinyl polymer can be obtained by addition polymerization (vinyl polymerization) is a vinyl group is preferable because of easy availability of the monomer and easy handling. As the polymerizable monomer containing a basic nitrogen-containing moiety, an acrylic acid derivative or a methacrylic acid derivative is preferable. As the polymerizable monomer containing a basic nitrogen-containing moiety, acrylate or methacrylate is more preferable. Of these, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, and diethylaminoethyl methacrylate are particularly preferable.

A polymerizable monomer having a protic neutral hydrophilic portion is one in which a non-polymerizable portion can dissociate to release a proton (H ⁺ ), and is extremely acidic, such as a carboxylic acid or a basic amino group, It is a polymerizable monomer that does not exhibit basicity. A polymerizable monomer having a protic neutral hydrophilic portion exhibits higher hydrophilicity than a polymerizable monomer having an aprotic neutral hydrophilic portion, and is excellent in blood priming properties and blood channeling prevention properties. Examples of the protic neutral hydrophilic moiety include a hydroxyl group, an aldehyde group having a proton at the α-position, an amide group having a proton at the α-position, and a 1,3-dicarbonyl group. As the protic neutral hydrophilic portion, a hydroxyl group is particularly preferable. Examples of the polymerizable monomer containing a protic neutral hydrophilic portion include 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, acrylamide, and methacrylamide, but the polymerizable monomer containing a protic neutral hydrophilic portion is limited to these. Is not to be done. Among them, a monomer in which a polymerizable moiety from which a vinyl polymer can be obtained by addition polymerization (vinyl polymerization) is a vinyl group is preferable because of easy availability of the monomer and easy handling. Among these, an acrylic acid derivative or a methacrylic acid derivative is preferable as the polymerizable monomer containing a protic neutral hydrophilic portion. As the polymerizable monomer containing a protic neutral hydrophilic portion, acrylate or methacrylate is most preferable.

  In the present specification, the “vinyl polymer” is a vinyl polymer in a broad sense and means a polymer having a non-cyclic main chain. Specific examples thereof include α-polyacrylic acid represented by “J Brandrup; E. H. Immergut. 1989.“ Polymer Handbook Third Edition ”A Willy-interscience Publication, pVII-5 to VII-18”. Substituents and derivatives thereof, polyvinyl ether, polyvinyl alcohol, polyvinyl ester, polystyrene and derivatives thereof, and copolymers containing these can be mentioned.

  The protonic neutral hydrophilic part of the polymer mainly ensures wettability for the entire filter to reach the formulation when the formulation is processed, especially for smooth operations such as “priming” that fills the formulation at the beginning of formulation processing. In addition, it is an essential part in the polymer for modifying the surface of the filter material.

  In order to highly remove abnormal prions in blood products containing plasma components, units derived from the above-mentioned hydrophobic polymerizable monomers, units derived from polymerizable monomers containing basic nitrogen-containing moieties, and protonic neutral hydrophilicity Polymers containing three of the units derived from polymerizable monomers containing moieties must be used. Abnormal prions cannot be removed to a high degree by a polymer composed of each single unit, and in particular, a high ability to remove abnormal prions from blood products containing plasma components cannot be obtained.

  An abnormal prion has three different binding regions that bind to a positively charged functional group, a negatively charged functional group, and a hydrophobic functional group. On the other hand, the isoelectric point of the abnormal prion is set to pH 4.6, and the pH of the blood product is between about 5 and 7.5, so that the abnormal prion in the blood product is negatively charged. Therefore, abnormal prions can be highly removed from blood products by units derived from basic monomers and units derived from hydrophobic monomers. In addition, it is said that the contact between a negatively charged material and a blood product causes the production of bradykinin that causes anaphylaxis such as blood pressure drop, flushing of the face, conjunctival redness, smooth muscle contraction, and pain. Is not suitable for coating the surface of a carrier for filtering blood products.

  On the other hand, when a blood product is filtered with a filter, it is required to provide a blood product with the same quality as when filtering with a current leukocyte removal filter. The protonic neutral hydrophilic part of the polymer is an essential part for ensuring wettability for blood products to spread throughout the filter, especially for smooth priming operation that fills the blood product with the filter at the beginning of filtration of the blood product. It is. Further, when the composition of the basic nitrogen-containing monomer and the hydrophobic polysynthetic monomer exceeds a certain level in the polymer, the quality deteriorates such as hemolysis or prolonged filtration time. Therefore, in order to obtain a blood product from which abnormal prions are highly removed, the composition of a hydrophobic polymerizable monomer, a polymerizable monomer containing a basic nitrogen-containing moiety, and a polymerizable monomer containing a protic neutral hydrophilic moiety is required. It is essential that it is set appropriately.

  The hydrophobic monomer in the present invention preferably has a solubility in water at 20 ° C. of 12 (g / 100 g of water) or less. When the solubility exceeds 12 (g / 100 g of water), the high leukocyte removal ability as obtained in the present invention tends to be difficult to obtain. The solubility is more preferably 2 (g / 100 g of water) or less. For the measurement of solubility, when the polymerizable monomer is a solid, a known measurement method such as a dew point method, a thermal analysis method, an electrical method for measuring the electromotive force or conductivity of a solution, a gas chromatography analysis method, a tracer method, etc. Can be measured. When the polymerizable monomer is a liquid, it can be measured by the same measurement method as when it is solid, but can also be measured by a known method such as a volumetric method, a light scattering method, a vapor pressure method or the like. Further, as a simpler method, when the boiling point of the polymerizable monomer is sufficiently higher than that of water, it can be obtained by a method of evaporating water from a saturated aqueous solution of the polymerizable monomer and measuring the weight of the remaining amount.

  In order to realize high leukocyte and platelet removal performance, preparation quality maintenance after filtration storage, and higher abnormal prion removal performance, the composition (mole percentage) of each of the monomers constituting the polymer should include a basic nitrogen-containing moiety. Protic neutral hydrophilicity in the remainder of the composition obtained by subtracting the composition of the polysynthetic monomer containing the basic nitrogen-containing moiety in the polymer from 100 mol% to 3 mol% or more and 5 mol% or less It is preferable that the mole% composition ratio (molar ratio, hereinafter referred to as “X”) of the hydrophobic polymerizable monomer to the polymerizable monomer including a portion is 0.52 or more and 0.67 or less.

  When the composition of the polymerizable monomer containing the basic nitrogen-containing moiety in the polymer exceeds 5 mol%, the surface charge of the polymer increases due to the increase in the basic nitrogen-containing moiety in the polymer, and the blood cell component and the polymer in the blood product are increased. This is not preferable because the frequency of contact due to the charged adsorption of the particles increases, thereby generating fine particles that damage the blood cell surface and lower the quality of the preparation after storage.

  On the other hand, if the composition of the polymerizable monomer containing a basic nitrogen-containing moiety in the polymer is less than 3 mol%, the charged part of the abnormal prion protein is polymerized due to a decrease in the charge of the polymer surface due to a decrease in the basic nitrogen-containing moiety in the polymer. This is not preferable because the adsorbing force is weakened and the prion removal performance is lowered.

  When the composition of the polymerizable monomer containing a basic nitrogen-containing moiety in the polymer is 3 mol% or more and 5 mol% or less, and X is less than 0.52, the hydrophobic moiety is reduced to reduce the hydrophobicity of the abnormal prion protein. It is not preferable because the ability of the sex part to adsorb to the polymer is weakened and the removal performance of abnormal prion protein is lowered.

  When the composition of the polymerizable monomer containing a basic nitrogen-containing moiety in the polymer is 3 mol% or more and 5 mol% or less and X is larger than 0.67, the hydrophobic portion increases and the surface charge of the polymer is relatively Increase. As a result, the blood cell component in the blood product is excessively adsorbed to damage the surface of the blood cell, and fine particles that deteriorate the quality of the product after storage are generated. Further, when the blood product is filtered with a removal filter filled with a carrier coated with a polymer, the wettability is poor with respect to the blood product and the treatment time is prolonged, which is not preferable.

  The composition of the monomer in the polymer can be measured by a general physicochemical method. If it illustrates about the physicochemical method which measures a copolymer composition, it can measure using well-known methods, such as a nuclear magnetic resonance spectrum method (NMR, -1H, -13C), and a pyrolysis GC mass spectrum method. It is also possible to confirm that the polymerization has been carried out as prepared and that there are lot-to-lot variations. In addition, the polymer coated on the surface of the filter material for removing leukocytes and platelets is dissolved and extracted using a solvent of the polymer, and the copolymer composition of each monomer in the polymer as the extraction substance is the same as described above. It can also be measured by the method. In addition, both the leukocyte and platelet removal filter material are dissolved in a deuterated solvent together with the polymer present on the surface, and the method of measurement by the nuclear magnetic resonance spectroscopy (NMR, -1H, -13C) method is also used. It can be used as a method for measuring the polymerization composition.

The weight average molecular weight of the polymer is obtained, for example, by preparing a sample solution in which the polymer is dissolved in the mobile phase at a concentration of 1.0 mg / mL and performing gel permeation chromatography measurement under the following conditions (poly Methyl methacrylate resin (PMMA) conversion).
Equipment: HLC-8220GPC (Tosoh Corporation)
Column: Shodex KF-606M, KF-601
Oven: 40 ° C
Mobile phase: 1.0 mL / min DMF + 5 mM LiBr
Detector: Differential refractive index detector

  The weight average molecular weight (Mw) of the polymer is preferably in the range of 50,000 to 3 million, more preferably in the range of 100,000 to 2 million, and in the range of 150,000 to 1.5 million. Is more preferable. When the weight average molecular weight (Mw) is 50,000 or more, elution of the polymer into the blood product can be sufficiently suppressed when leukocyte removal treatment is performed from the blood product containing leukocyte. Further, when the weight average molecular weight Mw is 3 million or less, the solubility in a solvent at the time of coating is sufficient, and the polymer can be stably produced at the time of polymerization.

  The polymer may be either a random copolymer or a block copolymer, but the block copolymer tends to have lower solubility in the solvent during coating, and the coating uniformity such as micelle formation in the solution Random copolymers are preferred because they tend to damage the surface. Either a straight-chain polymer or a branched polymer may be used, but the branched polymer chain tends to decrease the solubility in a solvent during coating, and the coating uniformity is impaired due to micelle formation in the solution. A linear polymer chain is more preferable.

  A general polymerization method may be used as a polymer synthesis method. Addition polymerization (vinyl polymerization) or the like that is a chain reaction may be used, and isomerization polymerization, elimination reaction that is a sequential reaction, polyaddition, polycondensation, addition polycondensation, or the like may be used. In polymerizing the polymer, radicals, ions, or the like may be used as the chain carrier. Examples of the polymerization method include solution polymerization, bulk polymerization, precipitation polymerization, and emulsion polymerization. Among these, solution polymerization is preferable.

The polymerization method is illustrated below.
Ethanol is used as a polymerization solvent, and an ethanol solution in which each monomer and diazo initiator are dissolved is dropped and reacted in a nitrogen atmosphere while stirring at a constant temperature below the boiling point of ethanol. Moreover, you may add a stabilizer etc. suitably. The reaction yield is measured and confirmed by a known method such as gas chromatography.

  Purify by using a general chemical purification method to remove impurities such as low molecular weight components and unreacted substances that may cause elution during preparation processing in the polymer or in the reaction liquid containing the polymer. Can do. Illustrative purification methods are: a method in which impurities are dissolved and a polymer is not dissolved, poured into a solvent and precipitated, and the precipitate is separated by filtration, decantation, etc. If necessary, a solvent having a slightly higher solubility than the precipitation solvent (precipitation) There can be mentioned a method in which the precipitate is washed with a solvent and a solvent mixture, etc., and dried under reduced pressure until the precipitate has a constant weight, and is obtained as a solid polymer.

[Carrier]
The carrier for adsorbing leukocytes and abnormal prions according to the present invention has a base material and the coating agent of the present invention fixed to the surface of the base material.

  Here, the substrate is not particularly limited as long as it has a pore capable of filtering blood, and includes any substrate. Specifically, a fibrous medium such as natural fiber, glass fiber, knitted fabric, woven fabric, and nonwoven fabric, a porous film, and a sponge-like structure having a three-dimensional network-like continuous hole are particularly preferable. There are no particular limitations as long as they do not easily damage blood cells, and various materials can be used, and examples include organic polymer materials, inorganic polymer materials, and metals. Among these, organic polymer materials are preferable substrates because they are excellent in processability such as cutting. For example, polyester, polyolefin, polyacrylonitrile, polyamide, polystyrene, polymethyl methacrylate, polyvinyl fluoride, polyurethane, polyvinyl alcohol, polyvinyl acetal, polysulfone, polyvinylidene fluoride, polytrifluorochlorovinyl, vinylidene fluoride-tetrafluoro Examples include, but are not limited to, ethylene copolymers, polyethersulfones, polyacrylates, butadiene-acrylonitrile copolymers, polyether-polyamide block copolymers, ethylene-vinyl alcohol copolymers, cellulose, and cellulose acetate. It is not something. Polyester and polyolefin are preferable, and polyester is particularly preferable.

In the carrier according to the present invention, the polymer is fixed on the surface of the base material so that the polymer is not easily eluted during the preparation process. The method for fixing the polymer to the substrate surface may be either by chemical covalent bonding or by physicochemical non-covalent bonding. When the amount of the polymer present is less than 0.6 mg / m ² per unit area of the total surface area of the carrier, the leukocyte removal ability tends to decrease, and when it exceeds 83 mg / m ² , the performance variation due to coating unevenness increases. This is not preferable. Abundance of the polymer is more preferably at most carriers total surface area per unit area 5 mg / ^{m 2} or more 50 mg / ^{m 2} is preferable, 5 mg / ^{m 2} or more 15 mg / ^{m 2} or less. The abundance per unit area of the total surface area of the carrier means a value obtained by dividing the total amount of polymer present on the substrate surface by the total surface area of the substrate.

In this specification, the total surface area (m ² ) of the substrate refers to a value obtained from the product of the weight (g) of the substrate and the specific surface area (m ² / g) of the substrate. The amount of the polymer present on the surface of the substrate can be measured by a general physicochemical method. As a method for measuring the amount of the polymer present on the substrate surface, for example, both the substrate and the polymer are dissolved in a deuterated solvent and measured by a nuclear magnetic resonance (NMR, -1H, -13C) method. The method of doing is mentioned.

  Examples of the method for fixing the polymer to the surface of the substrate include a method of fixing each polymerizable monomer or polymer described above to the substrate by a chemical covalent bond (such as grafting), a physicochemical non-covalent bond (ion). Examples thereof include known methods such as bonding (fan bonding, der Waals force, etc.) (such as coating) and embedding. More specifically, a method in which each polymerizable monomer or polymer is directly grafted to the substrate surface by a graft polymerization method such as radiation grafting or plasma grafting, or a surface in which the substrate is impregnated or coated / transferred in a solution in which the polymer is dissolved. The coating method is more preferable because it can be produced relatively easily and is stable and excellent in performance.

  The method for coating the base material of the polymer of the present invention is not particularly limited as long as the pores of the base material are not significantly blocked and the base material surface can be uniformly coated within a certain range. Can be used. For example, a method in which a base material is impregnated with a solution in which a polymer is dissolved, a method in which a solution in which a polymer is dissolved is sprayed on a base material (for example, a filter material), a base material (for example, a gravure roll) And a method of applying and transferring to a filter material), but is not limited thereto. Among these, a method of impregnating a base material in a solution in which a polymer is dissolved and squeezing the base material after impregnation, and a method of applying and transferring the solution in which the polymer is dissolved to a base material (for example, a filter material) using a gravure roll, etc. It is a more preferable method because of its excellent continuous productivity and low cost.

  As the solvent for dissolving the polymer, various solvents can be used without particular limitation as long as the base material is not significantly dissolved, aqueous solutions containing water and inorganic salts, alcohols such as methanol, ethanol, propanol, and butanol, Ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate and ethyl acetate, hydrocarbons such as benzene and cyclohexane, halogenated hydrocarbons such as chloroform and dichloromethane, sulfur-containing solvents such as dimethyl sulfoxide, dimethylformamide and dimethyl Examples include, but are not limited to, amides such as acetamide and a mixture of the above-described plurality of solvents in a soluble range.

  In addition, as drying after coating, use a method such as mechanical compression, gravity, removing excess solution by blowing a gas such as air or nitrogen, and heating at room temperature or in a dry gas or under reduced pressure. Can do. Moreover, in order to improve the adhesiveness of the polymer of this invention and a base material before coating, the surface of a base material can also be processed with suitable chemicals, such as an acid and an alkali, or can be irradiated with plasma. Furthermore, after the coating of the polymer, heat treatment and post-processing by irradiating radiation such as γ rays and electron beams can be applied to further enhance the adhesion between the substrate and the polymer. In addition, coating may be performed when manufacturing a base material, and may be performed after base material manufacture.

The physical structure of the carrier greatly contributes to the ability to remove leukocytes and abnormal prions. Therefore, in order to improve the ability to remove leukocytes and abnormal prions, the selection of the substrate used for the carrier is also an important factor. As the physical structure of the carrier, the specific surface area of the substrate is preferably 1.0 m ² / g or more and 5.0 m ² / g or less, and 1.1 m ² / g or more and 3.0 m ² / g or less. it is more preferable, and more preferably not more than 1.3 m ² / g or more 2.0 m ² / g. If the specific surface area of the substrate is less than 1.0 m ² / g, it is difficult to remove leukocytes and abnormal prions at a high rate. When the specific surface area of the substrate exceeds 5.0 m ² / g, the support can no longer be produced stably. Further, in the leukocyte and abnormal prion removal filter (hereinafter also referred to as “removal filter”) of the present invention described later, the carrier obtained from a substrate having a plurality of specific surface areas has a higher specific surface area toward the outlet side. It is preferable to arrange so as to be large.

The specific surface area (m ² / g) of the base material is, for example, a base material unit determined by the gas adsorption method (BET method) using “Accusorb 2100” manufactured by Shimadzu Corporation or an apparatus having specifications equivalent thereto. It is the surface area per weight.

  As the physical structure of the carrier, the porosity of the substrate is preferably 65% or more and 90% or less, and more preferably 75% or more and 88% or less. If the porosity is less than 65%, the filtration rate of blood or the like tends to be low, and it takes a long time to remove leukocytes and abnormal prions. Further, when the porosity exceeds 90%, the entangled portions of fibers and fibers that are liable to adhere abnormal prions and leukocytes are reduced, so that high leukocyte removal performance and abnormal prion removal performance tend to be difficult to obtain.

  The porosity (%) of the base material is, for example, the ratio of the space occupied per unit volume calculated from the base material thickness.

  When a fibrous medium such as a nonwoven fabric is used as the base material, the average fiber diameter is preferably 0.3 μm or more and 3.0 μm or less, more preferably 0.5 μm or more and 2.5 μm or less, and 1 μm or more and 2 μm or less. More preferably, it is as follows. In the removal filter of the present invention, it is preferable to arrange a carrier obtained from a plurality of substrates having an average fiber diameter so that the average fiber diameter becomes finer toward the outlet side. Further, in the removal filter of the present invention, a substrate having an average fiber diameter of 10 μm or more and 40 μm or less may be disposed on the inlet side from the carrier as needed, mainly for the purpose of removing fine aggregates.

  In this specification, the average fiber diameter of the base material means that an electron micrograph of a fibrous medium is randomly taken at about five places, and a transparent sheet on which a lattice is drawn is superimposed on the photograph taken above, and the diameter is Using known polystyrene latex as a control, the diameters of 100 fibers that overlap the intersections of the lattices are measured, and the average is calculated to obtain the average fiber diameter.

  As the physical structure of the carrier, the average pore diameter of the substrate is preferably 1 μm or more and 60 μm or less, more preferably 1 μm or more and 30 μm or less, and further preferably 1 μm or more and 20 μm or less. When the average pore size is less than 1 μm, the blood product tends to hardly flow. On the other hand, when it exceeds 60 μm, the leukocyte removing ability tends to be lowered. In the removal filter of the present invention, it is preferable to arrange a carrier obtained from a plurality of base materials having an average pore diameter so that the average pore diameter decreases toward the outlet side. In the removal filter of the present invention, a substrate having an average pore diameter of 50 μm or more and 200 μm or less, which is mainly intended for removal of microaggregates, may be disposed on the inlet side from the carrier as necessary. Furthermore, in the removal filter of the present invention, a post filter having an average pore diameter of 50 μm or more and 200 μm or less may be disposed on the outlet side of the carrier as needed, mainly for preventing drift. The average pore diameter of the base material is a value (mean flow pore size: MFP) measured using a Coulter R porometer manufactured by Coulter Electronics, for example, and a sample of about 50 mg.

[Removal filter]
The leukocyte and abnormal prion removal filter of the present invention is obtained by filling the carrier of the present invention into a container having an inlet and an outlet for blood (for example, a blood product). The removal filter may have a base material for capturing microaggregates on the upstream side (side closer to the inlet than the carrier) of the blood product, or based on the downstream side (side closer to the outlet than the carrier). There may be materials.

  The material of the container may be either a hard resin or a soft resin. In the case of a hard resin, examples of the material include phenol resin, acrylic resin, epoxy resin, formaldehyde resin, urea resin, silicon resin, ABS resin, nylon, hard polyurethane, polycarbonate, vinyl chloride, polyethylene, polypropylene, and polyester. In the case of a soft resin, a blood product inlet and outlet formed on a flexible synthetic resin sheet and welded at the periphery, a cylindrical molded product having a blood product inlet and outlet, or the like is used. . When the material is welded to the container together with the carrier according to the present invention, the material is preferably similar in thermal and electrical properties to the carrier, for example, soft polyvinyl chloride, polyurethane, ethylene-vinyl acetate. Polymers, polyolefins such as polyethylene and polypropylene, hydrogenated products of styrene-butadiene-styrene copolymers, thermoplastic elastomers such as styrene-isoprene-styrene copolymers or hydrogenated products thereof, and thermoplastic elastomers and polyolefins A suitable material is a mixture with a softener such as ethylene-ethyl acrylate. Among these, soft vinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyolefin, and thermoplastic elastomers containing these as main components are particularly preferred, and soft vinyl chloride and polyolefin are particularly preferable.

  The shape of the container is not particularly limited as long as it has a blood product inlet and a blood product outlet from which abnormal prions and leukocytes have been removed, but a shape corresponding to the shape of the carrier is preferable. For example, when the carrier has a flat plate shape, a flat container made of a polygon such as a quadrangle or a hexagon, or a curve such as a circle or an ellipse can be used. More specifically, the container is composed of an inlet side container having a blood product inlet and an outlet side container having a blood product outlet, both of which divide the inside of the carrier into two chambers by sandwiching the carrier directly or via a support, The shape which forms a flat filter can be illustrated. As another example, when the carrier is cylindrical, the container is preferably cylindrical as well. More specifically, the container is composed of a cylindrical body portion for containing a carrier, an inlet side header having a blood product inlet, and an outlet side header having a blood product outlet, and the inside of the container is introduced from the inlet by potting. A shape that forms a cylindrical filter divided into two chambers so that the liquid flows from the outer peripheral portion of the cylindrical carrier to the inner peripheral portion (or from the inner peripheral portion to the outer peripheral portion) can be exemplified.

The removal filter of the present invention is preferably capable of removing 99% or more of the number of white blood cells in the blood product when the blood product is filtered, more preferably 99.9% or more, and even more preferably 99.99% or more. . In other words, in terms of leukocyte removal performance, the value calculated according to the following formula (1) preferably indicates a removal performance of 2 or more (2 Log or more), preferably 3 or more (3 Log or more). More preferably, it exhibits a removal performance of 4 or more (4 Log or more).
Leukocyte removal performance = −Log 10 {[white blood cell concentration (cells / μL) (blood after filtration)] ÷ [white blood cell concentration (cells / μL) (blood before filtration)]} (1)

  The removal filter of the present invention can maintain the formulation quality after filtration. In the removal filter of the present invention, the number of fine particles generated in the blood product after filtration is preferably 200 or less, and more preferably 150 or less. A microparticle means what is detected with antibody IgGL-PE. It is also possible to maintain the formulation quality after storage after filtration. In the removal filter of the present invention, for example, the number of fine particles generated in the blood product after storage for 42 days after filtration is preferably 200 or less, and more preferably 150 or less.

When the removal filter uses a fibrous medium as a base material, the filling density when filling the container is preferably 0.1 g / cm ³ or more and 0.5 g / cm ³ or less, preferably 0.1 g / cm ^3. More preferably, it is 0.3 g / cm ³ or less. The filling density can be obtained from, for example, a distance (cm) in a compressed state in an actual container by cutting a non-woven fabric to be filled into a filling cut size (cm ² ), measuring its weight (g). it can.

When the removal filter uses a fibrous medium as a base material, if the average fiber diameter of the base material is less than 0.3 μm, the average pore diameter is less than 1 μm, or the packing density exceeds 0.5 g / cm ³ , If the average fiber diameter of the substrate is more than 3.0 μm, the average pore diameter is more than 60 μm, or the packing density is less than 0.1 g / cm ^3, it tends to cause clogging and increased pressure loss. It tends to decrease the ability to remove leukocytes and abnormal prions.

  When the removal filter uses a porous structure and a sponge-like structure having three-dimensional network-like continuous pores as a base material, the average pore diameter of the base material is preferably 1 μm or more and 60 μm or less, and is 5 μm or more and 50 μm or less. More preferably, the thickness is 10 μm or more and 40 μm or less. If the average pore diameter is less than 1 μm, blood cell clogging or pressure loss tends to occur, and if the average pore diameter exceeds 60 μm, the leukocyte removal ability tends to decrease.

[Blood products]
In this specification, a blood product is a liquid composed of single or plural kinds of blood components prepared from whole blood or whole blood, which may contain abnormal prions, or an anticoagulant in these liquids. And a liquid to which a storage solution or the like is added. Specific examples include, but are not limited to, whole blood preparations, red blood cell preparations, platelet preparations, plasma preparations, washed red blood cell suspensions, thawed red blood cell concentrates, synthetic blood, platelet rich plasma, buffy coats, etc. No.

  In this specification, the whole blood preparation refers to Citrate Phosphate Dexrose (CPD), Citrate Phosphate Dextose Adenine-1 (CPDA-1), Citrate Phosphate-2-Dextrose (CP2D), Acid It is a blood product to which preservatives such as Citrate Dextform Formula-A (ACD-A), Acid Citrate Dextform Formula-B (ACD-B), heparin, and an anticoagulant are added.

[How to remove abnormal prions]
In the present specification, abnormal prion means a mutant abnormal prion protein known to cause a disease called spongiform encephalopathy in humans and animals. An abnormal prion is a protein having the same amino acid sequence as that of a normal prion but having a changed structure rich in β-sheet, and is resistant to digestion by protease K. As diseases caused by abnormal prions, scrapie, an infectious degenerative disease of sheep and goat nervous systems, and BSE in cattle are widely known. The forms of human disease include sporadic Creutzfeldt-Jakob disease (sCJD), iatrogenic Creutzfeldt-Jakob disease, Gerstmann-Straeussler-Scheinker (GSS) syndrome, lethal familial isomnia (FFI) ), Kuru and there are mutant CJDs known to be infected by BSE meat.

  As used herein, an abnormal prion includes all or any one of the above diseases, or all types of abnormal prion proteins that cause the disease in any animal, particularly humans and livestock animals. By the way, Cambridge Healthtech Institute's 10th Annual Transmissible Spontaneous Encephalopathies of the C-Heldness-Clay of the Cambridge Health Institute's 10th Annual Transformatives The filter (LAPRF manufactured by Pall) was removed in the same manner, and there was almost no difference in the removal rate. This indicates that the abnormal prion protein structure related to filter removal performance is almost the same regardless of the type of animal or disease, and the removal rate of abnormal prion derived from human can be estimated from the removal rate of abnormal prion derived from animal. Is shown.

  Next, a method for removing abnormal prions from blood products will be described. First, one embodiment of a method for preparing various blood products will be described, but the present invention is not limited thereto.

(Preparation of abnormal prion-removed whole blood product)
Abnormal prion from whole blood by adding preservatives such as CPD, CPDA-1, CP2D, ACD-A, ACD-B, heparin and anticoagulant to the collected whole blood and filtering with the removal filter of the present invention To remove abnormal prion and obtain a whole blood product.

  FIG. 1 is a schematic diagram showing an embodiment of a system for filtering a whole blood product. The filtration of the whole blood product is performed by aseptically assembling the bag 1 containing at least the blood product, the removal filter 3 of the present invention, and the bag 4 for collecting the filtered blood product from which abnormal prions have been removed in this order by the circuit 2. This is done using a connected system. A blood collection needle, a blood collection bag, a bag for separating each component after centrifugation, or a circuit for collecting the blood product remaining in the removal filter may be connected. Filtration may be performed by flowing the blood product from the bag containing the blood product placed higher than the removal filter by gravity drop through the conduit to the removal filter, or by means such as a pump. The abnormal prion may be removed by flowing the blood product under pressure from the inlet side of the removal filter and / or reducing the pressure from the outlet side of the removal filter. This filtration method is not limited to whole blood products, but is the same for other blood products.

  In preparation of abnormal prion whole blood preparation, when removing abnormal prion before storage, preferably whole blood stored at room temperature or under refrigeration is preferably within 72 hours, more preferably within 24 hours, particularly preferably after collection. The abnormal prion-removed whole blood product is obtained by removing abnormal prions using the removal filter of the present invention within 12 hours, most preferably within 8 hours at room temperature or under refrigeration. When removing abnormal prions after storage, an abnormal prion-removed whole blood product is obtained by removing abnormal prions from whole blood stored at room temperature or under refrigeration, preferably using a filter within 24 hours before use. . In the present invention, it is also possible to obtain a whole blood preparation from which leukocytes are removed together with abnormal prions.

(Preparation of abnormal prion-removed erythrocyte preparation)
A preservation solution such as CPD, CPDA-1, CP2D, ACD-A, ACD-B, and heparin and an anticoagulant are added to the collected whole blood. Subsequent separation into each blood component is performed by centrifuging after removing abnormal prions from whole blood, or by separating red blood cells or red blood cells and buffy coat (hereinafter referred to as "BC") after centrifuging whole blood. ) May remove abnormal prions.

  When performing centrifugation after removing abnormal prions from whole blood, after obtaining abnormal prion-removed whole blood in the same manner as in the preparation of the abnormal prion-removed whole blood preparation, the abnormal prion-removed whole blood is centrifuged and concentrated in the lower layer. By collecting red blood cells, an abnormal prion-removed red blood cell preparation is obtained.

  When centrifuging whole blood before removing abnormal prions, the centrifugation conditions are weak centrifugation conditions that separate into red blood cells and platelet-rich plasma (PRP), and strong centrifugation that separates into red blood cells, BC, and platelet poor plasma (PPP). There are two types of conditions. Red blood cells separated and collected from whole blood as needed, or red blood cells containing BC are added to Saline Adenine Glucose Mannitol solution (SAGM), Additive solution-1 (AS-1), Additive solution-3 (AS-3), Additive After adding a preservative solution such as solution-5 (AS-5) or mannitol adenine phosphate (MAP), the erythrocyte preparation is filtered with the removal filter of the present invention to obtain an abnormal prion-removed erythrocyte preparation.

  In preparation of abnormal prion-removed erythrocyte preparation, whole blood stored preferably at room temperature or under refrigeration is preferably within 72 hours after blood collection, more preferably within 48 hours, particularly preferably within 24 hours, most preferably within 12 hours. Centrifuge. Also, when removing abnormal prions before storage, preferably within 120 hours after blood collection from an erythrocyte preparation stored at room temperature or refrigerated, more preferably within 72 hours, particularly preferably within 24 hours, most preferably Abnormal prion-removed erythrocyte preparation is obtained by removing the abnormal prion by filtering with the removal filter of the present invention at room temperature or under refrigeration within 12 hours. In the case of removing abnormal prions after storage, the abnormal prion-removed erythrocyte preparation is preferably removed by filtering the erythrocyte preparation stored at room temperature or under refrigeration with the removal filter of the present invention within 24 hours before use. Get.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this.

  Various numerical values used in Examples and Comparative Examples were measured by the following methods.

(Specific surface area of substrate)
The specific surface area (m ² / g) of the substrate (nonwoven fabric) was determined by a gas adsorption method (BET method) using Shimadzu Corporation “Acousobe 2100” or an apparatus having equivalent specifications. The nonwoven fabric weighed in the range of 0.50 g to 0.55 g was filled into a sample tube, and after deaeration treatment with the accusorb body at a reduced pressure of 1 × 10 ⁻⁴ mmHg (at room temperature) for 20 hours, as an adsorbed gas Using a krypton gas with a known adsorption occupation area, the total surface area in the nonwoven fabric weighed from the surface of the nonwoven fabric weighed at the temperature of liquid nitrogen and weighed was determined and divided by the weight of the weighed nonwoven fabric.

(Measurement of average fiber diameter)
An electron micrograph of the nonwoven fabric was randomly taken at about five locations for the nonwoven fabric, and the transparent sheet on which the lattice was drawn was superimposed on the photograph taken above, and the intersection of the lattice overlapped with polystyrene latex with a known diameter as a control, The diameters of 100 fibers were measured, and the average was calculated as the average fiber diameter.

(Abundance of polymer per unit area of total surface area of carrier)
A deuterated 1,1,1,3,3,3-hexafluoro-2-propanol was added to a deuterated 1,1,1,3,3,3-hexafluoro-2-propanol by coating a polyester nonwoven fabric with a polymer comprising methyl methacrylate, dimethylaminoethyl methacrylate, and 2-hydroxy methacrylate. Dissolve, perform NMR measurement, and the intensity ratio of the signal clearly belonging to the nonwoven fabric (for example, proton of benzene ring) and the signal clearly belonging to polymer (for example, proton of methyl group adjacent to ester of methyl methacrylate) From the copolymer composition of the polymer measured separately, the amount of polymer retained per unit weight of the nonwoven fabric was determined. Further, the amount of polymer retained per unit weight of the nonwoven fabric was converted from the specific surface area of the base material into the amount of polymer retained per unit area of the entire surface area of the support.

(Leukocyte removal performance test: Examples 1 to 5, Comparative Examples 1 to 7)
[Production of removal filter]
As a base material, polyester nonwoven fabric P having an average fiber diameter of 12 μm, a basis weight of 30 g / m ² , and a specific surface area of 0.24 m ² / g, an average fiber diameter of 1.8 μm, a basis weight of 60 g / m ² , and a specific surface area of 1.1 m ² / g Polyester nonwoven fabric A and polyester nonwoven fabric B having an average fiber diameter of 1.2 μm, a basis weight of 40 g / m ² , and a specific surface area of 1.47 m ² / g coated with the polymer prepared in each example and comparative example were used. The base materials P and A and the carrier B are stacked in order of PAB from the upstream side, and A ′ of the same base material as A and P ′ of the same base material are stacked on the downstream side as a whole. It was set as the laminated body of the symmetrical structure of PABA-A'-P '. The laminate is sandwiched between flexible vinyl chloride resin sheets having ports that serve as blood inlets or outlets, and the periphery of the laminate and flexible sheets are welded and integrated using a high-frequency welding machine, and the effective filtration area A 43 cm ² removal filter was prepared. In all evaluations, high-pressure steam sterilization was performed at 115 ° C. for 59 minutes.

[Leukocyte removal performance test]
Red blood cell preparations prepared according to European standards were used. This was filtered using a removal filter containing a polyester nonwoven fabric B coated with the polymers prepared in Examples 1 to 5 and Comparative Examples 1 to 7 with a natural drop of 100 cm, and blood was collected and used as blood after filtration. .

[Leukocyte removal performance]
The leukocyte removal performance was evaluated by the following formula (1).
Leukocyte removal performance = −Log 10 {[white blood cell concentration (cells / μL) (blood after filtration)] ÷ [white blood cell concentration (cells / μL) (blood before filtration)]} (1)
The leukocyte concentration was measured by sampling 100 μL of each blood and using a beaded Leucocount kit (manufactured by Nippon Becton Dickinson) by the flow cytometry method (apparatus: FACSCalibur manufactured by BECTON DICKINSON).

(Post-filtration formulation quality confirmation test: Examples 1 to 5, Comparative Examples 1 to 7)
The blood product used for blood evaluation was an erythrocyte product prepared according to European standards. The removal filter used for the evaluation was produced by the same method as the leukocyte removal performance test.

[Fine particle count test]
In the same manner as the leukocyte removal performance test, the blood product was filtered using a removal filter containing a polyester nonwoven fabric B coated with the polymer prepared in Examples 1 to 5 and Comparative Examples 1 to 7, and blood was collected and added. Blood was obtained after filtration. The number of fine particles in the blood stored refrigerated immediately after filtration and 42 days after filtration was measured.

[Formulation quality after filtration]
As for the number of fine particles, 10 mL of erythrocyte preparation was collected, 50 μL of plasma after centrifugation at 2,000 × g for 20 minutes and 10 μL of antibody IgGL-PE were mixed, allowed to stand in the dark at room temperature for 20 minutes, and 1% paraformaldehyde 2 mL of PBS / PBS was added, and allowed to stand in the dark at 2-8 ° C. for 30 minutes. Then, 50 μL of Flow-Count (manufactured by BECKMAN COULTER) was added to each, and a flow cytometry method (apparatus: Cytomics FC500, manufactured by BECKMAN COULTER) ).

(Abnormal prion removal performance evaluation: Examples 1 to 5, Comparative Examples 1 to 7)
The removal filter used for the evaluation was produced by the same method as the leukocyte removal performance test.

[Preparation of hamster brain infected with scrapie]
The hamster brain 65 to 70 days after inoculation of the 263K hamster-derived abnormal prion Sc237 that causes scrapie was used as the scrapie-infected hamster brain.

[Preparation of homogenate]
Scrapie-infected hamster brain was ultrasonically disrupted in 320 mM sucrose to produce 10 wt (g) / volume (100 ml)% (hereinafter referred to as “W / V%”) homogenate and added Used as a homogenate (hereinafter abbreviated as “homogenate”).

[Preparation of microsomal fraction]
The homogenate was centrifuged at 4500 × g for 30 minutes, and the supernatant was further centrifuged at 100,000 × g for 1 hour. The precipitate after centrifugation was resuspended in a solution of 150 mM NaCl, 20 mM Tris-HCl, pH 7.4, and further centrifuged at 100,000 × g for 1 hour. The precipitate after centrifugation was used as a microsomal fraction (hereinafter abbreviated as “microsomal fraction”) that was resuspended with PBS of pH 7.4 (Phosphate-Buffered Saline) and added.

[Method for Determining Concentration of Protease K]
After removing the leukocytes, the whole blood preparation is centrifuged at 4000 × g for 30 minutes, and 1.3 ml of microsomal fraction is added to 11.7 ml of the supernatant (hereinafter referred to as “pre-filtered blood”). Not added (hereinafter referred to as “pre-added blood before filtration”).

<Sample without protease K treatment>
3 mL of pre-filtered blood or 3 mL of non-added pre-filtered blood was centrifuged for 1 hour at 100,000 × g, 4 ° C. ± 2 ° C. The precipitate was resuspended in 100 μL sample buffer and incubated at 100 ° C. ± 5 ° C. for 5-10 minutes.

<Protease K-treated sample>
1 to 2% (w / v) Sarkosyl and protease K having different concentrations were mixed with 3 mL of pre-filtered blood or non-added pre-filtered blood, and centrifuged at 100,000 × g, 4 ° C. ± 2 ° C. for 1 hour. The precipitate was resuspended in 100 μL sample buffer and kept at 100 ° C. ± 5 ° C. for 5-10 minutes, respectively.

  A sample not treated with protease K and a sample treated with protease K are analyzed by Western blotting, and normal prion and non-specifically reacting protein with antibody are not completely detected by protease K, and abnormal prion is detected. The minimum concentration of protease K was determined.

[Abnormal prion removal performance test: Examples 1 to 5, Comparative Examples 1 to 7]
A leukocyte-free erythrocyte preparation prepared according to European standards was purchased and used. After storing in a refrigerator at 4 ° C. for 1 to 2 days, it was added at room temperature so that the microsomal fraction per unit of leukocyte-removed erythrocyte preparation was 9.5 mL to prepare pre-filtered blood. This was filtered using a removal filter containing a polyester nonwoven fabric B coated with the polymer prepared in Examples 1 to 5 and Comparative Examples 1 to 7 with a natural drop of 100 cm, and blood was collected and added and filtered. did. The blood before addition filtration and the blood after addition filtration were centrifuged at 4000 × g for 30 minutes, and the supernatant was dispensed. Protease K was added to these supernatants to the required minimum concentration determined above, and centrifuged at 100,000 × g, 4 ° C. ± 2 ° C. for 2 hours. After centrifugation, the pellet was resuspended with 100 μL sample buffer and kept at 100 ° C. ± 5 ° C. for 5-10 minutes.

[Analysis of abnormal prion titer]
Abnormal prions were detected by a general Western blot method using 3F4 as a primary antibody for blood products before and after addition filtration heated with sample buffer and heated. Detection of all pre- and post-filtration blood was repeated multiple times in a serial 3-fold dilution series, Spearman (Brit. J. of Psyology 1908; 2: 227 ff.) And Kaerber (Naunyn Schmiedeberg's Arhc. Exp. Path. Pharmac. 1931; 152: 380 ff.), ED50 was calculated and converted to ED50 per unit volume (1 mL), and the logarithmic value was used as the titer. The calculation method of ED50 is as follows.

Ｙ_０：繰り返し全てで異常プリオンを検出した最大希釈の対数値
ｄ：希釈系列の対数値
Ｙ_ｉ：Ｙ_０以上希釈したときの異常プリオンが検出された割合の和

Y ₀ : logarithm of the maximum dilution in which abnormal prions were detected in all repetitions d: logarithm of the dilution series
Y _i : Sum of ratios where abnormal prions are detected when Y ₀ or more is diluted

[Abnormal prion removal performance]
Abnormal prion removal performance was determined by the following equation (3).
Abnormal prion removal performance = Abnormal prion titer (blood before addition filtration)-Abnormal prion titer (blood after addition filtration) (3)

(Weight average molecular weight of polymer)
The weight average molecular weight of the polymer is obtained, for example, by preparing a sample solution in which the polymer is dissolved in the mobile phase at a concentration of 1.0 mg / mL and performing gel permeation chromatography measurement under the following conditions (poly Methyl methacrylate resin (PMMA) conversion).
Equipment: HLC-8220GPC (Tosoh Corporation)
Column: Shodex KF-606M, KF-601
Oven: 40 ° C
Mobile phase: 1.0 mL / min DMF + 5 mM LiBr
Detector: Differential refractive index detector

[Example 1]
Ethanol was used as a polymerization solvent, and while stirring at 78 ° C. in a nitrogen atmosphere, an ethanol solution in which a polymerizable monomer and a diazo initiator were dissolved was dropped to perform polymerization. The charge ratio (molar ratio) of each polymerizable monomer was as follows: 33 mol% methyl methacrylate (hereinafter abbreviated as “MMA”) as a hydrophobic polymerizable monomer, and dimethylaminoethyl methacrylate (as a polymerizable monomer containing a basic nitrogen-containing moiety). Hereinafter, it was 3 mol% (abbreviated as “DM”) and 64 mol% of 2-hydroxyethyl methacrylate (hereinafter abbreviated as “HEMA”) as a polymerizable monomer containing a protic neutral hydrophilic portion. The polymerization solution was purified with excess water and dried under reduced pressure. The copolymer composition of the polymer was measured by ¹ H-NMR. The results were almost as prepared, and the copolymer composition (molar fraction) in the polymer was 33 mol% for MMA, 3 mol% for DM, and 64 mol% for HEMA. MMA / HEMA was 0.52, and the weight average molecular weight Mw was 190,000. Ethanol was used as the coating solvent, and the polymer concentration was 0.5 w / v%. The polyester non-woven fabric B as the material (base material) was coated at the above polymer concentration. The abundance of the polymer per unit area of the total surface area of the carrier was 10 mg / m ² . When the leukocyte removal performance test, the fine particle count test after filtration storage and the abnormal prion removal performance test were performed by the above-described method, the leukocyte removal performance was 5.00 Log, the fine particles were 93 particles / μL immediately after filtration, and stored for 42 days after filtration. 131 pieces / μL, abnormal prion removal performance was 3.3 Log.

[Example 2]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerizable monomer was MMA 33 mol%, DM 5 mol%, and HEMA 62 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 33 mol% NMA, 5 mol% DM, and 62 mol% HEMA. MMA / HEMA was 0.53, and the weight average molecular weight Mw was 270,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 11 mg / m ² . When the leukocyte removal performance test, the microparticle count test after filtration storage and the abnormal prion removal performance test were performed by the above-mentioned methods, the leukocyte removal performance was 4.86 Log, the microparticles were 120 / μL immediately after filtration, and 42 days after filtration. 139 / μL, abnormal prion removal performance was 3.5 Log.

Example 3
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 38 mol%, DM 3 mol%, and HEMA 59 mol%. The copolymer composition of the polymer was measured by 1H-NMR. The copolymer composition in the polymer was 38 mol% for NMA, 3 mol% for DM, and 59 mol% for HEMA. MMA / HEMA was 0.64, and the weight average molecular weight Mw was 160,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 11 mg / m ² . When the leukocyte removal performance test, the microparticle count test after filtration storage and the abnormal prion removal performance test were performed by the above-mentioned methods, the leukocyte removal performance was 5.25 Log, the microparticles were 105 particles / μL immediately after filtration, and 42 days after filtration. 133 pieces / μL, abnormal prion removal performance was 3.1 Log.

Example 4
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 38 mol%, DM 5 mol%, and HEMA 57 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 38 mol% for NMA, 5 mol% for DM, and 57 mol% for HEMA. MMA / HEMA was 0.67, and the weight average molecular weight Mw was 220,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 12 mg / m ² . When the leukocyte removal performance test, the fine particle count test after filtration storage and the abnormal prion removal performance test were performed by the above-mentioned methods, the leukocyte removal performance was 4.93 Log, the fine particles were 98 particles / μL immediately after filtration, and after storage for 42 days after filtration. 119 pieces / μL, abnormal prion removal performance was 3.9 Log.

Example 5
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 35 mol%, DM 5 mol%, and HEMA 60 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 35 mol% NMA, 5 mol% DM, and 60 mol% HEMA. MMA / HEMA was 0.58, and the weight average molecular weight Mw was 210,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 10 mg / m ² . When the leukocyte removal performance test, the microparticle count test after filtration storage and the abnormal prion removal performance test were performed by the above-mentioned methods, the leukocyte removal performance was 5.15 Log, the microparticles were 122 cells / μL immediately after filtration, and 42 days after filtration. 150 / μL, abnormal prion removal performance was 3.7 Log.

[Comparative Example 1]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 25 mol%, DM 3 mol%, and HEMA 72 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 26 mol% NMA, 3 mol% DM, and 71 mol% HEMA. MMA / HEMA was 0.37, and the weight average molecular weight Mw was 190,000. The polyester nonwoven fabric B was coated at a polymer concentration of 0.8 w / v% using ethanol as the coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 16 mg / m ² . When the leukocyte removal performance test, the fine particle count test after filtration storage and the abnormal prion removal performance test were performed by the above-described methods, the white blood cell removal performance was 3.80 Log, the fine particles were 122 particles / μL immediately after filtration, and after storage for 42 days after filtration. 141 pieces / μL, abnormal prion removal performance was 1.6 Log.
When the copolymerization composition of the polysynthetic monomer containing a basic nitrogen-containing moiety is less than 5 mol%, and when MMA / HEMA is lower than 0.52, the adsorption of abnormal prions is reduced and the removal performance of abnormal prions is reduced. became.

[Comparative Example 2]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 20 mol%, DM 13 mol%, and HEMA 67 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 22 mol% NMA, 12 mol% DM, and 66 mol% HEMA. MMA / HEMA was 0.33 and the weight average molecular weight Mw was 390,000. The polyester nonwoven fabric B was coated at a polymer concentration of 0.8 w / v% using ethanol as the coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 17 mg / m ² . When the leukocyte removal performance test, the microparticle count test after filtration storage and the abnormal prion removal performance test were performed by the above-described methods, the leukocyte removal performance was 3.15 Log, the microparticles were 7868 / μL immediately after filtration, and 42 days after filtration. 30519 pieces / μL, abnormal prion removal performance was 3.5 Log.
When the copolymerization composition of the polysynthetic monomer containing a basic nitrogen-containing portion exceeds 5% and MMA / HEMA is smaller than 0.52, fine particles are generated immediately after filtration, resulting in an undesirable result in blood quality.

[Comparative Example 3]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 30 mol%, DM 10 mol%, and HEMA 60 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 30 mol% NMA, 10 mol% DM, and 60 mol% HEMA. MMA / HEMA was 0.50, and the weight average molecular weight Mw was 310,000. The polyester nonwoven fabric B was coated at a polymer concentration of 0.8 w / v% using ethanol as the coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 18 mg / m ² . When the leukocyte removal performance test, the microparticle count test after filtration storage and the abnormal prion removal performance test were performed by the above-described methods, the leukocyte removal performance was 3.85 Log, the microparticles were 123 / μL immediately after filtration, and 42 days after filtration. 28654 / μL, abnormal prion removal performance was 3.2 Log.
When the copolymerization composition of the polysynthetic monomer containing a basic nitrogen-containing portion exceeds 5% and MMA / HEMA is smaller than 0.52, fine particles are generated after filtration and storage, which is undesirable in terms of blood quality.

[Comparative Example 4]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 40 mol%, DM 5 mol%, and HEMA 55 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 42 mol% for NMA, 5 mol% for DM, and 53 mol% for HEMA. MMA / HEMA was 0.79, and the weight average molecular weight Mw was 270,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 10 mg / m ² . When the leukocyte removal performance test, the fine particle count test after filtration storage and the abnormal prion removal performance test were performed by the above-described methods, the leukocyte removal performance was 5.26 Log, the fine particles were 95 particles / μL immediately after filtration, and after storage for 42 days after filtration. 25316 / μL, abnormal prion removal performance was 3.9 Log.
When the copolymerization composition of the polysynthetic monomer containing a basic nitrogen-containing moiety was 5% and MMA / HEMA was larger than 0.67, fine particles were generated after filtration and storage, which was not preferable in terms of blood quality.

[Comparative Example 5]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 40 mol%, DM 13 mol%, and HEMA 67 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 40 mol% for NMA, 13 mol% for DM, and 47 mol% for HEMA. MMA / HEMA was 0.85, and the weight average molecular weight Mw was 190,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 10 mg / m ² . When the leukocyte removal performance test, the microparticle count test after filtration storage and the abnormal prion removal performance test were performed by the above-mentioned methods, the leukocyte removal performance was 4.83 Log, the microparticles were 17488 / μL immediately after filtration, and the storage was performed for 42 days after filtration. 69953 / μL, abnormal prion removal performance was 3.3 Log.
When the copolymerization composition of the polysynthetic monomer containing a basic nitrogen-containing portion exceeds 5% and MMA / HEMA is larger than 0.67, fine particles are generated after filtration and storage, which is undesirable in terms of blood quality.

[Comparative Example 6]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was 3 mol% DM and 97 mol% HEMA. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 3 mol% DM and 97 mol% HEMA. MMA / HEMA was 0.00, and the weight average molecular weight Mw was 550,000. The polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as the coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 8 mg / m ² . When the leukocyte removal performance test, the fine particle count test after filtration storage and the abnormal prion removal performance test were performed by the above-mentioned methods, the leukocyte removal performance was 5.11 Log, the fine particles were 118 particles / μL immediately after filtration, and after storage for 42 days after filtration. 130 pieces / μL, abnormal prion removal performance was 0.8 Log.
When the copolymerization composition of the polysynthetic monomer containing a basic nitrogen-containing moiety is less than 5 mol%, and when MMA / HEMA is lower than 0.52, the adsorption of abnormal prions is reduced and the removal performance of abnormal prions is reduced. became.

[Comparative Example 7]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 30 mol%, DM 3 mol%, and HEMA 67 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 30 mol% NMA, 3 mol% DM, and 67 mol% HEMA. MMA / HEMA was 0.45, and the weight average molecular weight Mw was 200,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 10 mg / m ² . When the leukocyte removal performance test, the fine particle count test after filtration storage and the abnormal prion removal performance test were performed by the above-mentioned methods, the leukocyte removal performance was 4.88 Log, the fine particles were 107 cells / μL immediately after filtration, and after storage for 42 days after filtration. 125 pieces / μL, abnormal prion removal performance was 0.5 Log.
When the copolymerization composition of the polysynthetic monomer containing a basic nitrogen-containing moiety is less than 5 mol%, and when MMA / HEMA is lower than 0.52, the adsorption of abnormal prions is reduced and the removal performance of abnormal prions is reduced. became.

[Comparative Example 8]
Polymerization, purification, and drying were carried out under the same conditions as in Example 1 except that the charging ratio of each polymerization monomer was MMA 35 mol%, DM 2 mol%, and HEMA 63 mol%. The copolymer composition of the polymer was measured by ¹ H-NMR. The copolymer composition in the polymer was 35 mol% NMA, 2 mol% DM, and 63 mol% HEMA. MMA / HEMA was 0.56, and the weight average molecular weight Mw was 140,000. Polyester nonwoven fabric B was coated at a polymer concentration of 0.5 w / v% using ethanol as a coating solvent. The abundance of the polymer per unit area of the total surface area of the carrier was 10 mg / m ² . When the leukocyte removal performance test, the fine particle count test after filtration storage and the abnormal prion removal performance test were performed by the above-described methods, the white blood cell removal performance was 4.97 Log, the fine particles were 125 / μL immediately after filtration, and the storage was performed for 42 days after filtration. 144 pieces / μL, abnormal prion removal performance was 1.5 Log.

  Table 1 shows the results of Examples and Comparative Examples.

表１中、「分子量」は重量平均分子量（Ｍｗ）を表し、「存在量」はポリマーの担体全表面積単位面積あたりの存在量を表す。

In Table 1, “molecular weight” represents the weight average molecular weight (Mw), and “abundance” represents the abundance per unit area of the total surface area of the polymer.

  The removal filter according to the present invention can remove undesirable components such as aggregates, leukocytes, and abnormal prions from blood products. Therefore, the above removal system can be used in a method for maintaining the quality in the preparation after filtration and storage, and a method for removing abnormal prions simultaneously with leukocytes from the blood preparation. These removal filters and methods are useful for preventing blood transfusion side effects caused by leukocytes, and also for preventing transfusion infection of transmissible spongiform encephalopathy (TSE) caused by abnormal prions in the field of transfusion medicine.

  DESCRIPTION OF SYMBOLS 1 ... Blood product bag, 2 ... Circuit, 3 ... Removal filter, 4 ... Bag which collects blood product after filtration

Claims (17)

A method for removing leukocytes and abnormal prions in a blood product, comprising a step of passing the blood product through a removal filter,
The removal filter comprises a container having an inlet and an outlet for blood, and a carrier filled in the container,
The carrier has a base material and a coating agent fixed to the surface of the base material,
The coating agent comprises a unit derived from a polymerizable monomer containing a basic nitrogen-containing moiety, a unit derived from a hydrophobic polymerizable monomer, and a unit derived from a polymerizable monomer containing a protonic neutral hydrophilic moiety. Hydrophobic polymerization of a unit derived from a polymerizable monomer containing a basic nitrogen-containing moiety and having a molar fraction of 3 mol% or more and 5 mol% or less and containing a protonic neutral hydrophilic moiety The removal method which consists of a polymer whose molar ratio of the unit derived from a sex monomer is 0.52-0.67.   The removal method according to claim 1, wherein the number of fine particles generated in the blood product after storage for 42 days after filtration is 200 or less. When the blood product is filtered,
The removal method according to claim 1 or 2, wherein the leukocyte removal performance is 4 Log or more, the abnormal prion removal performance is 3 Log or more, and the number of fine particles generated in the blood product after filtration is 200 or less.   The removal method according to any one of claims 1 to 3, wherein the polymer is a vinyl polymer.   The hydrophobic polymerizable monomer, the polymerizable monomer containing a basic nitrogen-containing moiety, and the polymerizable monomer containing a protic neutral hydrophilic moiety are all acrylic acid derivatives or methacrylic acid derivatives. The removal method as described in any one of these.   The removal method according to any one of claims 1 to 5, wherein the basic nitrogen-containing moiety is a tertiary amino group.   The removal method according to any one of claims 1 to 6, wherein the protic neutral hydrophilic portion is a hydroxyl group. The substrate is a fibrous medium;
Packing density to the container of the carrier is less than 0.1 g / cm ³ or more 0.5 g / cm ^3, a method of removing according to any one of claims 1 to 7.   The removal method according to any one of claims 1 to 8, wherein the substrate is a fibrous medium or a sponge-like structure. The specific surface area of the substrate is less than 1.0 m ² / g or more 5.0 m ² / g, the method of removing according to any one of claims 1-9.   The removal method as described in any one of Claims 1-10 whose average pore diameters of a base material are 1 micrometer or more and 60 micrometers or less.   The removal method as described in any one of Claims 1-11 whose porosity of a base material is 65% or more and 90% or less.   The removal method as described in any one of Claims 1-12 whose said base material is a nonwoven fabric.   The removal method as described in any one of Claims 1-13 whose average fiber diameters of the said nonwoven fabric are 0.3 micrometer or more and 3.0 micrometers or less.   Leukocyte and abnormal prion removal filter used in the removal method according to any one of claims 1 to 14.   The support | carrier used for the removal method as described in any one of Claims 1-14.   The coating agent which adsorb | sucks the leukocyte and abnormal prion used for the removal method as described in any one of Claims 1-14.

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