Binding of hepatitis virus particles to immobilised procion blue-HB and cibacron blue 3GA.

Two chemically similar triazine dyes, coupled to chromatographic gels, have been investigated for their ability to bind and retain hepatitis B surface antigen marker of the hepatitis B virus. Both dyes, Procion Blue-HB and Cibacron Blue 3GA, were effective in removing viral particles from plasma protein solutions. A number of combinations of dye and gel support have been tried, to obtain optimal binding. A Cibacron Blue-Trisacryl adsorbent achieved almost complete retention (greater than 99.5%) of HBsAg before breakthrough occurred. Binding was better at reduced flow rates and on large pore gel matrices, suggesting that steric restrictions limit the interaction. The interaction is directly between immobilised dye and the viral particle, rather than through plasma albumin, which also binds to these affinity adsorbents. These findings are important in the use of immobilised triazine dyes for plasma protein purification. Furthermore, the interaction may be utilised either for the removal of HB viral particles from plasma or as a rapid method of their purification.

A sensitive immunoradiometric assay for the detection of hepatitis B surface antigen.

A solid-phase immunoradiometric assay for hepatitis B surface antigen is described which has been in use since 1971. Initially it was used for reference laboratory work, but from 1974 it has also been used for screening blood and blood products. Methods for the production of reagents and their use in blood transfusion and reference work are outlined.

Plasma protein fraction: the disappearance of kinin from the solution on storage.

The kinin produced when plasma protein fraction was heated at 60 C for 10 hours in order to inactivate the agent of hepatitis was shown to lose its activity during storage. There was an 80 per cent loss after three months and negligible activity was detectable after six months of storage. Synthetic bradykinin treated and stored under the same conditions showed no loss in activity.

Anti-hepatitis B immunoglobulin for clinical use.

Anti-hepatitis B immunoglobulin, prepared by a method which involves the initial removal of the fibrinogen fraction, has been reported to lack certain antibodies and fail to detect certain hepatitis B surface antigens when used as a detector reagent in counter-immunoelectrophoresis. The possibility exists that any passive immunity conferred by the immunoglobulin might not protect against these antigens. Anti-hepatitis B immunoglobulin prepared from plasma by a modified technique which omitted the precipitation of the fibrinogen fraction reacted against these antigens in gel precipitin tests. It is suggested that such a method is preferable for the production of anti-hepatitis B surface immunoglobulin.

Detection of hepatitis-B surface antigen in plasma samples by reversed passive haemagglutination tests.

A comparison of two commercial reversed passive haemmagglutination tests with a counter-immunoelectrophoretic test, used to detect hepatitis-B surface antigen in reconstituted freeze-dried plasma, showed an increase in the number of positive results by the haemagglutination tests. No difficulty was encountered with the appearance of non-specific agglutination provided the plasma was heated at 60 degrees C for 30 min, frozen overnight at -35 degrees C, thawed and centrifuged before testing.

Gel precipitin tests for hepatitis-B surface antigen. False positive reactions due to the presence of staphylococcal antigen in contaminated plasma samples.

Plasma samples contaminated with coagulase-positive staphylococci were found to give a false positive precipitin line for hepatitis-B surface antigen in gel tests. The staphylococcal antibody was found to be present in both normal immunoglobulin and anti-hepatitis-B surface antigen immunoglobulin preparations and also in many normal plasma samples.