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Biomedical subjects

M Wickerhauser

Publications and source records attributed to M Wickerhauser.

At least 19 recordsLinked to original sources
PubMed1991

Large-scale preparation of a highly purified solvent-detergent treated factor VIII concentrate.

Large-scale adaptation of a recently reported glycine precipitation method for the production of factor VIII (FVIII) concentrate is described. Scaling up of the method required some modification including the addition of aluminum hydroxide to the glycine buffer to reduce the level of contaminating proteins in the final preparation and the use of centrifugation to replace filtration by glass beads. Furthermore, the resultant product was virus inactivated by incorporation of the organic solvent and detergent technique. At industrial level, the modified method gave a good recovery of FVIII activity (230 IU/l plasma) with high purity (4 IU/mg protein). The final product, after virus inactivation and lyophilization, yielded 185 IU of FVIII activity per liter of starting plasma and was considered to be suitable for clinical evaluation.

Detergents↗
PubMed1987

Heat stability of lyophilized C1 inactivator concentrates.

Heat stability of lyophilized C1 inactivator (C1-INA) concentrates of intermediate and high purity has been investigated under several heat treatment protocols that include heating for 96 and 192 h at 68 degrees C and for 10 h at 80, 90 and 100 degrees C. Both types of concentrate showed high stability in functional activity, with not more than 5% loss in any of the time-temperature combinations evaluated. However, the C1-INA antigen from both concentrates showed small but progressive changes in crossed immunoelectrophoretic pattern, in proportion to the intensity of heat treatment. High-pressure size-exclusion chromatography revealed only minimal signs of aggregation in the high-purity concentrate, but a significant and progressive aggregation of nonspecific protein contaminants present in the intermediate-purity concentrate, making the high-purity concentrate preferable for heat treatment.

Complement C1 Inactivator Proteins↗
PubMed1984

Pasteurization of C1 inactivator in the presence of citrate salts.

Conditions have been determined under which the C1 inactivator (C1-INA) can be pasteurized to reduce the risk of transfusion hepatitis associated with its use for replacement therapy in patients with genetic or acquired deficiencies. Recovery of 90% of the biological and immunological activity of a C1-INA concentrate was achieved following heat treatment for 10 h at 60 degrees C in the presence of 3 M potassium citrate. Crossed immunoelectrophoresis in heparinized agarose was used to demonstrate the ability of the pasteurized C1-INA to bind heparin and to form a precipitation pattern with antibody which was almost indistinguishable from that of an unheated control. High pressure liquid chromatography and enhancement of the fluorescence of 1,8-anilinonaphthalene sulfonate were used to show that other proteins present in the concentrate were also stabilized.

Citrates↗
PubMed1984

A single-step method for the isolation of antithrombin III.

A single-step method is described for the isolation of a highly purified antithrombin III (AT III) concentrate at a recovery of over 30% using affinity chromatography on heparin-Sepharose (HS). The polyethylene glycol precipitation step frequently employed in the preparation of AT III concentrates for clinical use has been eliminated and purification is accomplished entirely by optimizing the salt concentration in the HS washing buffer to enhance the desorption of impurities prior to elution of AT III. Pasteurization of the AT III concentrate in the presence of 0.5 M sodium citrate to minimize the risk of hepatitis decreases the recovery by about 20% and induces changes in the patterns obtained by polyacrylamide gel electrophoresis and by crossed immunoelectrophoresis in heparinized agarose gel.

Antithrombin III↗
PubMed1981

A simplified method for the preparation of immune-serum globulin.

This report describes the recovery of highly purified immune-serum globulin (ISG) from the 42% ethanol precipitate fraction (42% P) generated during the first step of albumin purification. The method consists of three purification steps: (1) reprecipitation of the 42% P at 20% ethanol, pH 7.2; (2) solubilization of ISG at 17% ethanol, pH 5.2, and (3) isoelectric precipitation of ISG at 25% ethanol, pH 7.2. ISG prepared by this method was homogeneous when subjected to immunoelectrophoresis and polyacrylamide gel electrophoresis, and gave a yield equivalent to 4.7 g/l plasma, corresponding to a final recovery of over 48%.

Chemical Fractionation↗
PubMed1980

Replacement therapy in hereditary angioedema: successful treatment of acute episodes of angioedema with partly purified C1 inhibitor.

Although considerable progress has been made during the past two decades in the use of androgens to prevent attacks of hereditary angioedema, replacement of the deficient C1-inhibitor protein would provide a useful menas of treatment once an attack has begun. We studied the clinical use of C1 inhibitor that was partly purified on a large scale from pooled plasma. The in vivo efficacy and safety of this protein concentrate were evaluated during 11 intravenous infusions in eight patients with hereditary angioedema. Three patients received the C1-inhibitor preparation during an asymptomatic period. Increases in serum C4 activity provided evidence of the biologic activity of the infused inhibitor. Intravenous administration of the concentrate during acute abdominal or laryngeal attacks of hereditary angioedema in five patients resulted in abatement of symptoms in addition to increased serum C4 activity. No untoward effects of the intravenous administration of the C1 inhibitor were observed in these eight patients. Thus, this C1-inhibitor preparation seems to offer the potential for safe, effective replacement therapy and may provide a means of controlling an attack of hereditary angioedema that is in progress.

Angioedema↗
PubMed1979

Development of large scale fractionation methods. VII. Preparation of antithrombin III concentrate.

A large scale method for preparation of antithrombin III (AT III) concentrate from plasma or from Cohn fraction IV-1 (Fr. IV-1) has been described. It consists of the following steps: (a) partial purification by precipitation of impurities with 20% polyethylene glycol (PEG) 4000; (b) isolation of AT III from the PEG supernatant by batch adsorption and elution on heparin-Sepharose at a ratio corresponding to 45 vol of plasma or 80 vol of 10% Fr. IV-1 solution to 1 vol of gel; (c) concentration and desalting of the eluted AT III on a Pellicon ultrafiltration system; (d) pasteurization of AT III concentrate by heating for 10 h at 60 degrees C in the presence of 0.5 M sodium citrate at pH 7.5; (e) removal of excess citrate by gel filtration on Sephadex G-50; and (f) sterile filtration, filling and lyophilization. The recovery by activity was 32% from a 113-liter plasma batch and 16% from a 42-kg Fr. IV-1 batch. Both AT III concentrates, derived either from plasma or from Fr. IV-1, had similar specific activity and electrophoretic purity, were nonpyrogenic and met all other FDA requirements for biologic products. Pasteurization induced changes in disc gel and isotachophoretic patterns of AT III preparations.

Adsorption↗
PubMedDate not supplied

Preparation of antihemophilic factor from indated plasma.

Four large-scale batches of Antihemophilic Factor (AHF, factor VIII) were prepared from plasma derived from 4 to 6-day-old blood applying a method developed for preparation of AHF from fresh frozen plasma. The AHF product was 6 to 9-fold concentrated over plasma with 7 to 10-fold purification and a recovery of 100 to 140 factor VIII units per liter of starting plasma. In terms of purity and yield, this is about half that of AHF obtained from fresh frozen plasma. The AHF concentrate was free of detectable thrombin and plasmin and the solubility of the dry product was comparable to that of the product derived from fresh plasma but the hemoglobin content was slightly increased. After further fractionation with polyethylene glycol (PEG 4000), a highly soluble AHF product 100-fold purified, and 30-fold concentrated, was obtained with 60% factor VIII recovery, which corresponds to a final yield of 60 to 85 factor VIII units per liter of starting plasma.

Factor VIII↗