JPH0622627B2 - Adsorbent for hepatitis B virus removal - Google Patents

Description

TECHNICAL FIELD The present invention relates to an adsorbent which selectively removes hepatitis B virus present in blood (plasma).

(Prior Art) Today, it is estimated that there are 200 million carriers of hepatitis B worldwide.
Among them, it is said that there are about 2 to 3 million carriers in Japan. It is known that hepatitis B is transmitted by blood transfusion, but when hepatitis B is affected, it is about 10%.
It is said that the disease may progress to serious diseases such as chronic hepatitis, cirrhosis and liver cancer. However, at this stage, a fundamental treatment method for a patient who has developed hepatitis B has not been established, and it is regarded as one of intractable diseases.

When hepatitis B virus infects hepatocytes, in acute infection state transiently, hepatitis B antigen sustained blood chronic infectious conditions (hereinafter referred to as H _B antigen) it is released.

Therefore, whether infected with hepatitis B can be known by detecting the H _B antigen in the patient's blood.

Such H _B antigen has a molecular weight of about 3,000,000 and consists of lipids and proteins. Morphological The H _B antigen positive average 20nm around the spherical particles contained in a large amount in the serum, a large spherical particles having a tubular core particles spherical particles and the spherical particles are fused and diameter 24 nm (core) (Dane particles) 3 types of common antigen are recognized, and these 3 types of common antigen are
_BS antigen and Dane particle core antigen are called _HBC antigens.

In addition to the _HBS virus and the _HBC antigen, there is an _HBE antigen that is a protein having a molecular weight of about several hundred thousand independent of the _HBS antigen. This _HBE antigen is particularly infectious and is said to have a close relationship with the transition to chronic hepatitis and cirrhosis.

Hepatitis B is mainly transmitted by blood transfusion (plasma transfusion), but in order to prevent this, it is important to secure hepatitis B virus-uncontaminated blood (plasma) in which the hepatitis B virus is inactivated. The following treatment has been conventionally performed as such a hepatitis B virus inactivation method.

(1) Heat treatment Blood (plasma) is heat-treated at a temperature of 60 ° C. for 10 hours (2) Drug treatment Blood (plasma) is treated with a drug using glutaraldehyde, sodium hypochlorite, etc. (Problems to be solved by the invention However, the conventional hepatitis B virus inactivation method has a problem that useful components such as albumin, globulin and fibrinogen in blood (plasma) are denatured by heat or a drug. In addition, the heat treatment method, which is currently widely used as a method for producing plasma for blood transfusion, has a problem that the treatment efficiency is poor because it requires a long treatment time.

Furthermore, recently using an adsorbent with an antibody immobilized on the surface,
Attempts have been made to remove hepatitis B virus by antibody reaction. However, in this method, the procedure for immobilizing the antibody is complicated, and the obtained adsorbent is expensive, so it cannot be said to be a practical method.

(Means for Solving Problems) The present inventors effectively remove hepatitis B virus as one of methods for effectively inactivating hepatitis B virus existing in blood (plasma). Although it is possible to do so, in order to simultaneously adsorb and remove useful proteins such as albumin in blood (plasma), attention is paid to an adsorption method that has never been studied as a method for removing hepatitis B virus, and earnest research is conducted. As a result of stacking, hepatitis B in blood (plasma) is a substantially non-porous granular substance having acidic groups on the surface and no pores for adsorbing proteins in blood (plasma). The inventors of the present invention have found that the virus is selectively reduced and have reached the present invention. That is, the present invention is an adsorbent for removing hepatitis B virus, which is a substantially non-porous and granular material having an acidic group on the surface.

The adsorbent used in the present invention must have a substantially non-porous surface. “Substantially non-porous” includes a porous adsorbent having pores having a very small pore diameter (100 Å or less) even though it is porous. With such an adsorbent, useful components such as proteins in blood (plasma) cannot enter the pores, and thus are hardly adsorbed.

The adsorbent must further have an acidic group such as a carboxyl group or a sulfonic acid group on the surface. The hepatitis B virus cannot be removed with a granular material having no acidic group on the surface. As the granules having acidic groups on the surface, non-porous granules such as ion exchange resin and solid acid, or non-porous or porous granules such as glass, alumina and silica, which have acidic groups on the surface A granular material coated with a flexible film is used. As the ion-exchange resin having an acidic group, a strongly acidic cation-exchange resin having a sulfonic acid group is particularly preferable and, for example, Amberlite IR-120, Diaion PK-228, Dowex 50WX _{8 and the} like are used. As the solid acid, SiO ₂ —Al ₂ O ₃ type such as activated clay is preferably used. On the other hand, glass that does not have acidic groups, alumina, silica,
In the case of a granular material such as activated carbon, its surface can be coated with a polymer having an acidic group such as a carboxyl group or a sulfonic acid group. Examples of such a polymer include polyacrylic acid, polymethacrylic acid, polystyrene sulfonic acid, and a copolymer of a monomer which is a constituent unit of these polymers and a hydrophilic monomer. Examples of the hydrophilic monomer include hydrophilic acrylic acid ester monomers and hydrophilic methacrylic acid ester monomers. As a method for coating the surface of the granular material with a polymer having an acidic group,
The mixture of the monomer and the polymerization initiator may be dissolved in a suitable solvent such as methanol or ethanol, and the granular material may be coated by dipping, spraying, wet coagulation method or the like.

In the case of silica or glass, an acidic group can be introduced by surface treatment of the granular material in addition to the above coating method. The carboxyl group can be introduced by introducing an amino group with γ-aminopropyltriethoxysilane and then reacting it with succinic anhydride or succinic acid in the presence of carbodiimide. The sulfonic acid group can be introduced by treating the product with glutaraldehyde to introduce an aldehyde group after the aminosilanization treatment and further treating it with taurine.

Since the granular material used in the present invention is brought into contact with blood or plasma, the diameter is preferably in the range of 0.1 mm to 5 mm, more preferably 0.2 mm to 2 mm. If the particle size is smaller than 0.1 mm, the pressure loss of the adsorbent layer increases, causing problems such as hemolysis. If the particle size is larger than 5 mm, the voids between the particles become large and the adsorption performance is deteriorated, which is not preferable.

Further, since the adsorbent is in contact with blood to enhance safety against blood cell components, it is preferable that the adsorbent has a spherical outer shape.

The adsorbent of the present invention is usually packed in a column before use. The column allows blood and the like to pass but does not pass the adsorbent between the adsorbent layer and the inlet / outlet, and the main body having an inlet and an outlet having a shape capable of easily connecting to the blood circuit on both sides of the adsorbent layer. 8
A column equipped with a filter having a mesh of 0 to 180 mesh is preferable, but a column having substantially the same function can be used for this purpose even if it has another shape. As the material of the column, glass, polyethylene, polypropylene, polycarbonate, polystyrene, polymethylmethacrylate, etc. can be used, but polypropylene and polycarbonate which can be sterilized by autoclave are preferable. The filter may be physiologically inert and has high strength, but polyester is particularly preferable.

The column packed with the adsorbent of the present invention is usually sterilized and used, and autoclave sterilization and γ-ray sterilization are preferable.

The adsorbent of the present invention can be brought into contact with whole blood as it is, but may be brought into contact with only plasma that has been separated in advance with a plasma separation device or the like.

Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to such embodiments.

Example 1 Cation exchange resin Amberlite IR-120B (SO ₃ Na type) manufactured by Nippon Organo Co., Ltd. was converted to acid type (SO ₃ H type) with 10% hydrochloric acid aqueous solution, and chlorine ion was added with distilled water. It was washed with water until no more was detected and then air dried. This is the internal volume 5
ml was filled into a glass tube H _BS antigen, and after the H _B antigen values of H _BE antigen sera 75,6 respectively passed through at a flow rate of 10 ml / min, was measured for H _B antigen level in the serum , H _BS
Each antigen is H _B antigen values of H _BE antigen, become 7,1,
Especially H _B antigen values of H _BE antigen was equally summer and the value of the control sera.

Example 2 Activated clay from Mizusawa Chemical Industry Co., Ltd. (pore size 100 Å or less)
Was filled in a glass tube in the same manner as in Example 1,
After the same serum was a pass and, by measurement of H _B antigen level in serum, H _BS antigen, H _B antigen values of H _BE antigen respectively 2
It became 7 and 1, and it was revealed that the removal ability of H _BE antigen was excellent.

Example 3 Silica-alumina (pore size 100 Å or less) manufactured by JGC Chemical Co., Ltd. was filled in a glass tube having an internal volume of 5 ml in the same manner as in Example 1, and serum was treated by the same method as in Example 1. rear,
H _BS antigen, was measured for H _B antigen values of H _BE antigens were each reduced to 32,3.

Example 4 Non-porous granular activated carbon manufactured by Kureha Chemical Co., Ltd. was used as styrene-
The maleic acid copolymer (maleic acid content: 20 mol%) was immersed in a solution dissolved in acetone, taken out, and air-dried.
After drying, the polymer concentration was adjusted to 2% by weight.
After treating serum with this adsorbent in the same manner as in Example 1, the H _B antigen values of H _BS antigen and H _BE antigen were measured and found to be 50 and 2, respectively.

Using non-porous granular activated carbon made by Comparative Example 1 Kureha Chemical Co., after processing by connexion serum same manner as in Example 1, H _BS
The antigen and _HBE antigen levels were measured to be 64 and
It was 4.

(Operation) According to the present invention, as described above, the effect that hepatitis B virus can be efficiently removed is obtained by treating blood (plasma) with an adsorbent having an acidic group on the surface as described above. However, such an effect is completely unpredictable from the conventional knowledge.

Although the reason for producing such an effect is not clear, it is presumed that the acidic groups on the surface of the granular material are chemically bonded to the hepatitis B virus.

(Effects of the Invention) As described above, the adsorbent of the present invention can not only selectively adsorb and remove hepatitis B virus, but also has very little loss of useful components such as albumin and globulin, and its practical significance is extremely large. Is.

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Claims (1)

[Claims] 1. An adsorbent for removing hepatitis B virus, which is substantially non-porous and comprises a granular material having an acidic group on the surface.