Freedom from transmission of hepatitis-B of gamma-globulin and heat-inactivated plasma protein fraction prepared from contaminated human plasma by fractionation with solid-phase polyelectrolytes

Study of the immunogenicity and infectivity of hepatitis B-containing stabilized plasma-protein solution

In early 1984, five patients who were undergoing plasmapheresis at a Melbourne hospital developed a transient hepatitis B surface antigenaemia. A common batch of stabilized plasma-protein solution (SPPS) that was included in the replacement therapy for each patient was found to contain hepatitis B surface antigen (HBsAg). A follow-up study was undertaken of these patients and others who were known to have received SPPS from the same batch (in total, 10 patients were followed for a median of 46.5 weeks). No patient developed evidence of hepatitis, although one patient developed antibody to surface antigen. It was concluded that the manufacturing process was effective in destroying the infectivity of the HBsAg-positive plasma that was used in this batch of SPPS and that the final product was poorly immunogenic in these patients.

Removal of hepatitis B virus infectivity from human gamma-globulin prepared by ion-exchange chromatography

Hepatitis B virus infectivity can be removed from human plasma used to prepare a gamma-globulin product by ion-exchange chromatography with commercially available resins. A pooled human plasma sample free of hepatitis markers was contaminated with 10,000 chimpanzee infectious doses of hepatitis B virus per milliliter from a known infectious inoculum. The contaminated plasma was diluted to yield a weakly positive radioimmunoassay result for HBsAg and then processed over a double-column chromatography system containing anionic ion-exchange resins to yield highly purified gamma-globulin. Two chimpanzees were each inoculated intravenously with this product while a control animal received non-treated material. The 2 experimental animals each received a potential challenge of 3,000 ID and showed no serologic evidence of the disease during 9 months of evaluation. The control animal received 100 ID and developed hepatitis B 25 weeks after the challenge.

Hepatitis B virus, hepatitis non-A, non-B virus and hepatitis delta virus in lyophilized antihemophilic factor: relative sensitivity to heat

Lyophilized plasma derivatives are more stable to heat than when they are in the liquid state. Commercial Factor VIII (antihemophilic factor) was seeded with a measured quantity of hepatitis B virus. The contaminated material was then lyophilized and subjected to heat of 60 degrees C for 30 hr. Chimpanzees were inoculated with the heat-treated antihemophilic factor or sham-treated antihemophilic factor that had been held at 4 degrees C. Surprisingly, hepatitis B virus survived the heating procedure with no apparent loss in titer: the incubation period to appearance of HBsAg was that expected for the challenge dose of virus. Even more surprising, one chimpanzee (the recipient of the unheated antihemophilic factor) also developed non-A, non-B hepatitis and two chimpanzees (recipients of the heated antihemophilic factor) also developed delta hepatitis. Neither of these agents was a contaminant of the hepatitis B virus challenge pool, since the purity of this hepatitis B virus pool was established previously in chimpanzees. Thus, both a non-A, non-B agent and the delta agent apparently contaminated the commercial antihemophilic factor. This is the first direct evidence for contamination of antihemophilic factor with the delta agent and confirms previous seroepidemiologic evidence for its presence in pooled plasma derivatives. Subsequent inactivation studies were performed with antihemophilic factor experimentally contaminated with the Hutchinson strain of non-A, non-B hepatitis virus. In these studies, heating at 60 degrees C for 30 hr in the dry state rendered antihemophilic factor free of detectable non-A, non-B hepatitis virus.

Response to infusions of polyelectrolyte fractionated human factor VIII concentrate in human haemophilia A and von Willebrand's disease

Factor VIII was purified from cryoprecipitate by ion exchange chromatography on solid phase polyelectrolyte E-5 (PE-E5). The product was highly purified (3.5 u VIII:C/mg protein) compared to conventional concentrate (0.3 u VIII:C/mg protein) with low fibrinogen, low isoagglutinin titre, and a ratio of factor VIII coagulant activity (VIII:C) to factor VII related antigen (VIIIR:Ag) of 16:1. Trial infusions of this material (PE VIII) were given to three patients with severe haemophilia A and one patient with homozygous von Willebrand's disease. These patients also each received separate infusions of intermediate purity concentrate (IPC) for comparison. There were no adverse effects. The mean half life of VIII:C after PE VIII infusion in the haemophiliacs was 10.9 h and after IPC was 12.1 h, a statistically insignificant difference. The survival of factor VIII coagulant antigen (VIII:CAg) was similar to that of VIII:C. In contrast, the half life of VIII:C and of VIII:CAg was very short after infusion of PE VIII in the patient wih von Willebrand's disease (2.4 h). IPC when infused in this patient produced a typical secondary rise of VIII:C. Two bleeding episodes in severe haemophiliacs were satisfactorily treated with PE VIII. PE-E5 deserves further study as a means of preparing clinical concentrates of factor VIII.

Partial purification of biologically active, low molecular weight, human antihemophilic factor free of Von Willebrand factor. I. Partial characterization and evidence for disulfide bond(s) susceptible to limited reduction

Partially purified (approx. 5000-fold), low molecular weight human antihemophilic factor, free of detectable Von Willebrand factor (ristocetin cofactor activity or Von Willebrand antigen), was prepared from fresh citrated plasma by limited reduction with 1 mM dithiothreitol and chromatography on Sepharose CL-4B, Sephadex G-100, and polyelectrolyte E-5. The ratio of antihemophilic factor activity to Von Willebrand factor activity or antigen was greater than 27 000 : 1. The antihemophilic factor activity could be neutralized with homologous antibody and could be further increased with thrombin. The Mr (approx. 116 000) was determined by calibrated gel permeation chromatography, electrophoresis in 5% polyacrylamide gels with sodium dodecyl sulfate and by electrophoresis in large-pore acrylamide gels without it. Since the low Mr antihemophilic factor could be prepared by treating fresh rather than fresh-frozen plasma with dithiothreitol, it was concluded that partial reduction of the antihemophilic factor with this reagent helped to maintain the antihemophilic factor in a low Mr form. When iodo[l-14C]acetamide was used to alkylate the reduced plasma proteins prior to purification, the molecular weight of the purified antihemophilic factor remained low despite numerous purification steps. By this means, one of four radioactive proteins (Mr 116 000) in the final preparation was bound specifically to homologous antihemophilic factor antibody and attributed to 14C-labeled antihemophilic factor. While the data suggest that antihemophilic factor in fresh plasma contains one or more dithiothreitol-sensitive intramolecular disulfide bonds, the possibility of disulfide linkages with other proteins(s) cannot be excluded.