FI93516B - Method of Preparation of Parenterally Administerable Blood Products - Google Patents

Description

93516

Method for preparing blood products for parenteral administration

The invention relates to a process according to the preamble of claim 1 for the preparation of blood products for plasma administration parenterally.

Known methods for preparing human blood products use not only fractionation measures but also methods for purifying the corresponding product to remove contaminants that can cause side reactions. Examples are methods for removing vasoactive substances (EP 0 120 835, EP 0 122 909) and for inactivating viruses which may be present in such preparations (EP 0 159 311, U.S. Pat. No. 4,297,344).

However, these known methods do not take into account the problems of possible immunomodulatory side effects of the products. The first indication of possible therapy-mediated immunomodulation is provided by studies performed in patients with hemophilia. These patients showed a higher susceptibility to certain bacterial and viral infections (cf. e.g., AC Beddall et al., J. Clin. Pathol. 1985 38, 1163-1165; Hämophilie, K. Lechner in "Hand-buch der inneren Medizin", pp. 143, Part II / 9, 1985, Springer Verlag, PH Levine et al., Health of the Intensively Treated Hemophiliac, With Special Reference to Abnormal Liver Chemistries and Splenomegaly, 1977, 50, 1-9, BA Mcverry et al. , J. Clin. Pathol. 1979 32, 377-381). Further, deficiencies in lymphocytes isolated from the peripheral blood of these patients suggest disorders of the immune system. Examples include the shift in the relationship between T helper and T inhibitor cells (CM Kessler et al., 1983, Lancet, 991-992; P. Saidi et al., 1983, New Engl. J. Med. 308, 1291-1292). ), a decrease in "natural killer" cell activity (MM Lederman et al., N. Engl. J. Med. 1983 308, 79-82) and a decrease in the supply capacity of circulating mononuclear phagocyte antigens (JW Mannhalter et al., Clin. Immunol Immunopathol. 1986 38, 390-397).

The invention solves the problems presented by providing parenterally administrable blood products which are substantially free of immunomodulatory components, as evidenced by the absence or absence of down-modulation of Fc receptors in the leukocyte membrane, respectively.

By this is meant that the expression of Fc-receptor receptors on immunoglobulin G in the membrane of Fc receptor-positive leukocytes, e.g. monocytes, is not reduced or at least not significantly reduced, i. up to 30%, after interaction with a blood product. The expression of Fc receptors in the membrane of monocytes is determined by the ability of these cells to collect immunoglobulin G-loaded erythrocytes. Results are expressed as the percentage of cells forming the rosette (% RFZ). A method for determining downmodulation of Fc receptors is known and is described, for example, in J. W. Mannhalter et al., Clinical Immunology, and Immunopathology 1986 38, 390-397; A. Berken et al., J. Exp. Med. 1966 123, 119-144 and C. S. Scott,

Clin. exp. Immunol. 1979 38, 300 - 305.

The expression of immunoglobulin G Fc body receptors (Fc receptors) in the monocyte membrane is an important prerequisite for the proper functioning of the immune control. These receptors not only facilitate phagocytosis of opsonizing pathogens (Contemporary Topics in Immunobiology, Vol. 14, Regulation of Leukocyte Function, R. Snyderman, ed., Plenum Press New York and London 1971); the interaction of these receptors with their ligands also triggers a number of signals relevant to the regulated course of immunoprotection [induction of oxygen radical formation (RB Jonston et al., J. Exp. Med. 1976 143, 1551-1556; DN Rush et al., Cellular Immunology 1984 87, 252-258 and SD Wright, J. Exp. Med.

1983 158, 2016-2023), T cell activation (JA Griffin et al., J. Exp. Med. 1979 150, 653-675 and FM Griffin et al., J. Immunol. 1980 125, 844-49), antigen supply (J.

W. Mannhalter et al., Clin. Immunol. Immunopathol. 1986 39, 491-503)]. Down-modulation of Fc receptors therefore has significant clinical consequences and could help to improve the susceptibility of patients treated with blood products.

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Blood products that are substantially free of immunomodulatory components are prepared according to the invention by molecular screening of blood products, namely gel permeation chromatography (gel filtration) and / or by treating the blood products with a molecular sieve-like carrier to which the immunomodulatory components are selectively adsorbed. nm, whereby filtration can be further supported by an adsorption effect.

More specifically, the method according to the invention is characterized by what is set forth in the characterizing part of claim 1.

In gel permeation chromatography (gel filtration), molecules are separated according to their molecular weight. The gel consists of microscopically small spheres containing pores of a certain size. Molecules larger than these pores cannot penetrate the gel and are eluted first. Smaller molecules can penetrate the gel pores, retaining them and thus migrating more slowly. In this way, separation of individual proteins in the protein mixture can be achieved.

A preferred embodiment for the selective adsorption of immunomodulatory components is such that the blood products are treated with an adsorbent consisting of an inert carrier such as sepharose bound to immobilized ligands, in particular bacterial proteins such as staphylococcal protein A, .

Another method of this type is provided by treating blood products with an adsorbent consisting of an inert carrier such as sepharose to which antibodies obtained by immunization with immunomodulatory agents have been bound.

In a filtration process which is particularly suitable for the preparation of gamma globulin preparations, the particles are separated according to their size. The method used uses special filtration membranes with a very small pore size (less than 10 nm). Particles larger than these pores are retained by the membrane during the filtration process. In this way, large (high molecular weight) particles can be separated from the protein mixture.

The blood products of the invention are preferably suitable for use in the treatment of inherited or acquired coagulation disorders, for the treatment of primary and secondary immune deficiencies, and for the treatment of autoimmune, immune complex and infectious diseases.

The following examples explain the properties of the blood products of the invention, their preparation and the determination of any down-modulation that may occur compared to blood product-free controls.

Example 1

The factor VIII preparation is prepared according to the method described in EP 0 127 603. This preparation was subjected to affinity chromatography with immobilized protein A according to the "batch" method. The lyophilized factor VIII preparation containing 500 IU factor VIII was dissolved in 20 ml of distilled water supplemented with 10 IU of preservative-free heparin (Immuno Ag, Vienna) and dialyzed overnight against citrate buffer (2 L) ( 0.024 M sodium citrate, 0.120 M NaCl, adjusted with HCl to pH 7.2, added 10 IU / ml preservative-free heparin, hereinafter abbreviated as "citrate pH 7.2"). 8 ml of dialysate (corresponding to about 200 IU factor XIII) was removed and mixed with 2 ml of protein A-Sepharose suspension (50% suspension (v / v) citrate at pH 7.2, protein A-Sepharose was pre-equilibrated at citrate pH 72). The incubator was then incubated for 4 hours at room temperature with occasional shaking. At the end of the incubation period, protein A-Sepharose was centrifuged off (5 min, 700 x g, room temperature), the mother liquor was pipetted off and the gel was washed 3 more times with 10 ml of citrate pH 7.2. The individual centrifugation solutions were pooled, sterile filtered, adjusted to 2 IU factor VIII / ml and stored at 4 ° C for testing.

The Factor VIII preparation prepared as described herein and treated in accordance with the invention was assayed for its immunomodulatory activity as follows.

Mononuclear cells derived from peripheral blood were isolated by density gradient centrifugation (J. W. Mannhalter et al., Clin. Immunol. Immunopathol. 1986 38, 390-397). An 8 ml density gradient (Lymphoprep, Nyegaard & Co., Oslo, Norway) was then coated with 20-25 ml of heparinized blood and centrifuged for 35 minutes at room temperature (400 x g). Mononuclear cells accumulated at the plasma-gradient interface were aspirated, washed 3 times with physiological saline, and suspended in RPMI-1640 medium containing 15% pooled, heat-inactivated (30 min, 56 ° C) AB serum and penicillin (100 IE / ml), streptomycin (100 myg / ml) and L-glutamine (2 mM) (RPMI supplement).

Isolation of monocytes from the mononuclear cell population occurred by infection. Unlike other mononuclear blood cells, monocytes have the property of accumulating on glass or plastic surfaces. To isolate monocytes, mononuclear cells were adjusted to a concentration of 1 x 10? cells / ml RPMI supplement. 2 ml of this suspension was then pipetted into plastic tissue culture dishes (Makroplatte TC, Greiner & Söhne, Kremsmunster, Austria) and incubated for 3 hours in a CO 2 incubator cabinet (5% CO 2, more than 95% zn air humidity) at 37 ° C. Cells that had not been adhered to 6,93516 were then pipetted off. The collected cells (monocytes) were washed 3 times with physiological saline, RPMI supplement medium was added and stored in a CO 2 incubator cabinet until later use.

The expression of Fc receptors in the membrane of monocytes was demonstrated by the accumulation of IgG-loaded bovine erythrocytes (A. Berken et al., J. Exp. Med. 1966 123, 119-144). Bovine blood was taken up in Alsever solution and washed several times in phosphate buffered saline, pH 7.2-7.4 (PBS). The erythrocyte concentration was then adjusted to 2% in PBS. Erythrocyte loading with immunoglobulin G occurred by incubation with a subagglutinating dose of anti-bovine erythrocyte antibody (IgG fraction: 0.167 mg / ml PBS, incubation time 1 hour, 37 ° C) (CS Scott, Clin. Exp. Immunol. 1979 3j). , 300 - 305). At the end of the incubation period, free IgG was removed by washing 3 times in PBS and antibody-loaded erythrocytes were adjusted to a concentration of 0.5% in PBS containing 0.2% bovine serum albumin (PBS-BSA). This erythrocyte suspension could now be used to detect Fc receptors in the monocyte membrane.

To this end, monocytes isolated in plastic tissue culture dishes were first removed from the tissue culture dish by gently sweeping and adjusted to a concentration of 2-3 x 10 6 cells / ml PBS-BSA. 100 of this monocyte suspension was then mixed with 100 of the above erythrocyte suspension and centrifuged at 4 ° C for 10 minutes (120 xg). Incubate for 1 hour at 0 ° C, then the pelleted cells were gently resuspended and the percentage of monocytes that had collected erythrocytes was determined by phase contrast microscopy. At least 200 monocytes were examined for their ability to collect IgG-loaded erythrocytes. Results are presented as percent (% RFZ) or collection index (AI) of rosette-forming cells. A rosette is a monocyte that has collected at least 3 erythrocytes. Collection-

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Index 7 9351 6 shows the average number of erythrocytes collected per monocyte.

Factor VIII preparation was tested by adding factor VIII (2 IU / ml) to the cells immediately after collecting the monocytes in plastic tissue culture dishes and incubating for one hour at 37 ° C in a CO 2 incubator. At the end of the incubation period, adherent monocytes were washed 4 times with physiological saline, RPMI supplement was added. and incubated for 16 hours in a CO 2 incubator cabinet at 37 ° C. This incubation time is required for contaminants in blood products to perform their immunomodulatory effect. After this 16 hour incubation period, the expression of Fc receptors on the monocyte membrane is determined according to the method described above.

As a control, monocytes were incubated immediately after collection with RPMI-1640 medium, but without factor VIII, for one hour and otherwise treated as described above.

The results of Fc receptor expression are presented as the percentage of rosette-forming cells (% RFX) as well as the collection index (AI).

8 9351 6

Monocyte Factor VIII-% RFZ1 AI <b> Incubation_______Activity__ RPMI Medium - 81 ± 2 4.42 ± 0.05 (control)

Factor VIII 2 IU / ml 20 ± 3 0.79 ± 0.06 (starting product)

Factor VIII 2 IU / ml 75 ± 4 3.78 ± 0.15 (protein treated according to the invention with α-sepharose) a) percentage of monocytes that have collected at least three IgG-loaded erythrocytes b) average number of collected erythrocytes per monocyte. All counted monocytes (both those that had not collected erythrocytes and all that had one or more erythrocytes collected) were used to calculate AI.

From this, it can be seen that the factor VHI starting product causes Fc receptor expression from a modulation of 81% RFZ to 20% RFZ. In comparison, after the interaction between the monocytes and the factor VIII preparation treated according to the invention, the percentage of rosin-forming cells is 75%. The difference of 81% in RFZ controls and 75% RFZ after interaction with the factor VIII preparation treated according to the invention is not significant (Students t test for paired randomized trials). This means that the factor VIII product treated according to the invention is free of immunomodulatory components, because after the interaction between monocytes and the product treated according to the invention, the RFZ value does not differ from the control value (% RFZ in monocytes without factor VIII treatment).

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Example 2,500 IE in Suokela H. et al. Vox. Sang. The lyophilized factor IX preparation prepared according to the method described in 1977 21/37 to 50 was dissolved in 20 ml of distilled water and dialyzed overnight against citrate buffer (2 L, citrate pH 7.2, the exact composition of this buffer is shown in Example 1). ) At 4 ° C. 8 ml (corresponding to about 200 IU of factor IX) was removed and subjected to affinity chromatography on protein A-Sepharose in a column method. In this case, 8 ml of factor IX preparation were pumped at a flow rate of 0.1 ml / min. protein A through a Sepharose column (column C 10/10, Pharmacia, 1 ml gel volume) pre-equilibrated with 50 ml of citrate pH 7.2. Factor XI pumped through the column was adjusted to 2 IU / ml, sterile filtered and stored at 4 ° C until testing. The immunomodulatory activity of the starting preparation and the factor IX preparation treated according to the invention as described was tested as described in Example 1. The results of these studies are presented in the following table.

Monocyte Factor IX-% RFZ ^ a ^ AI * b * incubation_activity____ RPMI medium - 75 ± 1 4.09 ± 0.04 (control)

Factor IX 2 IU / ml 42 ± 3 2.31 ± 0.07 (starting product)

Factor IX 2 IU / ml 70 ± 3 4.00 ± 0.08 • percentage of cells forming 1 rosette treated according to the invention, i.e. the percentage of counted monocytes that have collected at least three IgG-loaded erythrocytes 93516 10 b) collection index, i.e. the average number of erythrocytes collected per monocyte.

The results in this table show that the interaction of factor IX and monocytes resulted in a decrease in Fc receptor expression from 75% RFZ (controls) to 42% RFZ (after interaction with factor IX). However, after the interaction between the monocytes and the factor IX product treated according to the invention, the Fc receptor expression was 70% RFZ. The difference between 75% RFZ in controls and 70% RFZ after interaction with factor IX treated according to the invention is not significant (Students t test for paired randomized trials), which means that factor IX products treated according to the invention are free of immunomodulatory properties.

Example 3

The lyophilized FEIBA preparation (500 IU, Immuno AG) was dissolved in 20 ml of distilled water and dialyzed as described in Examples 1 and 2 for factor VIII or factor IX, respectively, against citrate pH 7.2. Removal of immunomodulatory agents was performed by adsorption chromatography on protein A-Sepharose according to the column method. The exact procedure was the same as in Example 2 for factor IX. Testing of the immunomodulatory properties of the starting product and the FEIBA preparation treated according to the invention was performed as described in Example 1.

The results of these studies, shown in the following table, show that treatment with immobilized protein A according to the invention removes immunomodulatory properties from FEIBA.

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FEIBA-% RFZ <a) AI (b> incubation_activity_ RPMI medium - 75 ± 1 4, Q9 ± 0.04 (control) FEIBA 2 IU / ml 34 ± 4 1.89 ± 0.15 (starting product) FEIBA 2 IE / ml 73 ± 1 3.94 ± 0.05 (treated with immobilized protein A according to the invention) a) percentage of rosin-forming cells, i.e. the percentage of monocytes that have collected at least three IgG-loaded erythrocytes b) a collection index, i.e. the average number of erythrocytes collected per monocyte.

It should be noted that in all the coagulation factor preparations tested (factor VIII, factor IX, FEIBA), the immunomodulatory properties are removed by treatment with immobilized protein A according to both the batch method and the column method.

Example 4

An immunoglobulin G preparation (i.m. IgG) suitable for intramuscular use was prepared by ethanol fractionation (H. F. Deutsch et al., J. Biol. Chem. 1946 164, 109 ff.). This preparation was subjected to gel permeation chromatography. At this time, the separation column (K 50/60, Pharmacia) was packed with 750 ml of chromatography gel (Sephacryl S 300, Pharmacia) and equilibrated with phosphate buffer (20 mM KCl 2, 0.15 M NaCl, 0.02% NaN 3 O, pH 8.0). This column was loaded with 300 μg i.m. IgG (10 ml in phosphate buffer) and eluted at a flow rate of 1 ml / min. The eluates 12,935,6 were taken in 11 ml fractions and the protein content was determined with a UV detector at 280 nm. The elution curves shown in the drawing were obtained. Fractions marked with * - ^ were pooled and tested for immunomodulatory activity as described in Example 1. The results of these studies are shown in the following table, which shows that this treatment has been sufficient to release the immunoglobulin G preparation from the immunomodulatory components. The RFZ value obtained from the monocytes and the i.m. After the interaction between IgG, is essentially consistent with the control value.

The i.m. IgG% RFZ ^ a ^ Al ^ b) incubation_mg / ml_ RPMI medium - 84 ± 3 7.11 ± 0.22 (control) i.m. IgG 10.8 20 ± 2 1.97 ± 0.07 (starting product) i.m. IgG 11.3 64 ± 2 5.94 ± 0.04 (after treatment according to the invention by gel permeation chromatography) a) percentage of rosette-forming cells, i.e. the percentage of monocytes that have collected at least three IgG-loaded erythrocytes b) storage index, i.e. the average number of erythrocytes collected per monocyte.

Example 5

The immunoglobulin G preparation (i.m. IgG) prepared as described in Example 4 was placed at a concentration of 50 mg / ml in phosphate buffered saline.

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13,93516 (PBS). After a corresponding pre-clarification with a suitable filter, the preparation was filtered through a special filter with a very small pore size (Sartorius SM 11318, pore size 10 nm). The filter membrane was then placed in a suitable filter holder and 20 ml i.m. was filtered through the filter. IgG solution at a pressure of 1 to 1.5 bar. The filtrate was then tested for possible immunomodulatory properties as described in Example 1. The results presented in the following table show that this treatment removes most of the immunomodulatory properties of the preparation. When treating monocytes i.m. The IgG starting product provides a reduction in Fc receptor expression from 79% to 21%, while the Fc receptor expression of monocytes after interaction with the product treated according to the invention is 67%. The i.m. Thus, the IgG fraction is substantially free of immunomodulatory properties.

The i.m. IgG% RFZ ^ a ^ incubation_mg / ml_ RPMI medium - 79 ± 3 (control) i.m. IgG 10.0 21 ± 3 (starting product) i.m. IgG 10.0 67 ± 2 (after treatment according to the invention by filtration through a special filter with a pore size of 10 nm) ___________ a) percentage of rosette-forming cells, i.e. percentage of monocytes that have collected at least three IgG-loaded erythrocytes 9351 6 14

Example 6

The factor VIII preparation was prepared according to the method described in EP-A-0 127 603. This preparation was subjected to affinity chromatography with immobilized antibodies directed against the immunomodulatory component.

To prepare the antibodies required for affinity chromatography, the immunomodulatory component was first isolated from the factor VIII preparation prepared as described above. This was accomplished by a combination of affinity chromatography and column chromatography. To this end, 2500 IU of factor VIII was dissolved in 100 ml of distilled water and dialyzed against citrate pH 7.2 for 24 hours. This product was then applied to a column packed with immobilized protein A (protein A sepharose, 12 ml gel volume, column C 10/20, Pharmacia, Sweden) and circulated overnight at room temperature at a flow rate of 0.5 ml / min. The column was then washed with 100 ml of citrate pH 7.2 (flow rate 0.5 ml / min.). Protein A-Sepharose-bound material was then eluted with acidic citrate buffer (50 mM trisodium citrate, 50 mM citric acid, pH 3.0, hereinafter "citrate pH 3.0") and immediately after elution with 1 M sodium phosphate buffer, pH 8. 5. After dialysis in PBS, this material was subjected to molecular sieve chromatography. The dialyzed protein A eluate was then applied to a Superase Prep Grade column (HR 16/50) and chromatographed at a flow rate of 0.5 ml / min. Fractions with a molecular weight greater than 400 kD contained an immunomodulatory component, as noted in the rose test already presented. These fractions were pooled and used to make antibodies in experimental animals.

150 μg of the immunomodulatory component (200 ml of PBS) and 200 μl of complete Freund's adjuvant were mixed together and immunized the rabbit at two sites subcutaneously. After 21 and 28 days of primary immunization, booster immunizations were performed in the same manner. From day 35 onwards, n.

30 ml of blood and serum was prepared. Serum samples from different blood collection days were then pooled and the immunoglobulin G fraction was isolated.

Ammonium sulfate was then added to the serum until 35% saturation, stirred for 25 minutes at room temperature, and then centrifuged (800 x g) for 15 minutes. The precipitate was resuspended in 33% saturated ammonium sulfate, stirred for 15 minutes and recentrifuged. The precipitate thus obtained was dissolved in PBS containing 0.1% sodium azide, and molecular sieve chromatography was performed on a Superase Prep Grade column (HR 16/50, flow rate 0.5 ml / min). Fractions with a molecular weight of 150 kD (i.e., immunoglobulin G-containing fractions) were collected and dialyzed against 0.1 M sodium bicarbonate, 0.5 M sodium chloride, pH 8.5 (= attachment buffer).

The antibodies thus obtained were then immobilized by attachment to cyanogen bromide (CNBr) -activated Sepharose (Pharmacia guideline). At this time, 4 g of CNBr-activated Sepharose 4B (Pharmacia, Sweden) in 1 mM hydrochloric acid was swollen and washed on a glass filter with 300 ml of 1 mM hydrochloric acid. 10 ml of gel and 40 ml of antibody in equilibration buffer (corresponding to 90 mg of protein) were mixed and incubated with occasional shaking for 2 hours at room temperature. It was then centrifuged (800 x g, 15 min), washed by resuspension in ligation buffer and centrifugation, and the gel material was suspended in 50 ml of blocking buffer (= ligation buffer + 1 M ethanolamine). Incubate for 2 hours at room temperature and then wash the gel material, namely first in 100 ml of 0.1 M Tris, 0.5 M sodium chloride, pH 8.0, and then in 100 ml of 0.1 M glacial acetic acid, 0.5 M sodium chloride, pH 4.0. The pH 8 to pH 4 washing steps were repeated 3 times. (Gel washing was performed by resuspension and centrifugation.) Last, the gel material was suspended in 20 ml of PBS + 10 IU heparin / ml. The analysis showed that 9 mg of antibody / ml of gel directed against the immunomodulatory component was bound.

4.5 ml of this gel was packed on a chromatography column (c 10/10, Pharmacia, Sweden) and rinsed successively with 30 ml of 3% bovine serum albumin (in PBS), 50 ml of 50 mM trisodium citrate, 50 mM citric acid ( pH 3.0) and finally with 200 ml PBS (containing 10 IU / ml heparin) (flow rate 0.5 ml / min.). This gel substance was then used to separate the immunomodulatory component.

This separation can be performed in both the "batch" and column methods. In the example, the separation of the immunomodulatory component from the factor VIII preparation is performed as described in the column method. According to the same principle, the immunomodulatory component can also be distinguished from factor IX and FEIBA preparations.

In Example 500, the factor VIII preparation prepared as described above is dissolved in 20 ml of distilled water and dialyzed twice within 24 hours each time against PBS (1 L) containing 10 IU / ml heparin. The concentration of the factor VIII preparation was then adjusted to 10 IU factor VIII / ml with the same buffer. 100 IU of this substance was then applied to the above separation column (sepharose with antibodies against the immunomodulatory component) and circulated for 16 hours at room temperature through the column at a flow rate of 0.5 ml / min. The unbound material was then adjusted to 2 IE factor VIII / ml and tested for immunomodulatory activity by the rose test as described in Example 1. The results of these studies are presented in the following table.

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Monocyte Factor VIII-% RFZ ^ a ^ Al ^ b * incubation_activity_ RPMI medium - 81 ± 3 6.06 * 1.76 (control)

Factor VIII 2 IU / ml 31 ± 5 1.36 * 0.13 (starting product)

Factor VIII 2 IU / ml 80 * 6 4.79 * 1.45 (treated according to the invention) a) percentage of rosin-forming cells, i.e. the percentage of monocytes that have collected at least three IgG-loaded erythrocytes b) a collection index, i.e. the average number of erythrocytes collected per monocyte.

The results presented in this table clearly demonstrate the immunomodulatory activity of the factor VHI starting product. The interaction between monocytes and the parent product reduced Fc receptor expression from 81 * 3% RFZ (controls) to 31 * 5% RFZ (after interaction with factor VIII). In comparison, the interaction between monocytes and the factor VIII product treated according to the invention did not reduce Fc receptors in the monocyte membrane (81 ± 3% after interaction with the RFZ control compared to 80 * 6% RFZ after the interaction with the factor VIII product treated according to the invention). ). The difference between 81 * 3% RFZ and 80 * 6% RFZ is not statistically significant (Students t test for paired randomized trials), and this means that the factor VIII product treated according to the invention is free of immunomodulatory properties.

Claims (4)

1. A method for producing such parenterally administrable blood plasma-resistant blood products that are substantially free from immune modulating components, which is expressed in the absence of the modulation of Fc receptors, respectively. fails in the membranes of the leukocytes, provided that the expression of the receptors of the Fc pieces of immunoglobulin G in the membranes of the monocytes after coagulation, a blood product preparation is not reduced, or that the reduction is highest up to 30%, characterized by: - the blood products are exposed to the molecular products, in particular, gel permeation chromatography (gel filtration), or - the blood products are treated with a molecularly filterable carrier on which immunomodulatory components are selectively adsorbed, or - the blood products are filtered on a filter having a pore size not exceeding 10 nm. 2. A method according to claim 1, characterized in that the blood products are treated with an adsorbent constituting an inert carrier material in which immobilized ligands are bound, in particular proteins of bacterial origin, such as protein A of staphylococci or protein G respectively. . protein M of streptococci. Method according to claim 1 or 2, characterized in that the blood products are treated with an adsorbent consisting of an inert carrier material in which antibodies are bound, which are produced by immunization by immunomodulatory substances. Method according to claim 2 or 3, characterized in that, as an inert carrier material, a product is marketed under the trademark Sepharose.