ABSTRACT
This report describes a study of in vitro proliferative and antibody responses to the hepatitis B virus surface antigen (HBsAg) of lymphocytes from chronic HBsAg carriers, subjects with naturally acquired immunity, and responders to the hepatitis B vaccine. Peripheral blood T and B lymphocytes were cultured with a wide range of concentrations of HBsAg (0.025-250 ng/ml). We were unable to detect HBsAg-specific proliferation or antibody synthesis in any of the subject groups studied, despite the use of a range of antigen concentrations, cell ratios and culture periods. The addition of recombinant interleukin 2 (rIL-2) or T cell growth factor at either initiation or day 3 of culture enhanced proliferative responses, but in an antigen-independent manner. In contrast to the proliferation observed following the addition of IL-2, the absence of responses to specific antigen suggest there may be low numbers of HBsAg-specific precursors in the peripheral blood.
Subject(s)
B-Lymphocytes/immunology , Carrier State/immunology , Hepatitis B Surface Antigens/immunology , Hepatitis B/immunology , T-Lymphocytes/immunology , Adult , B-Lymphocytes/drug effects , Cells, Cultured , Female , Hepatitis B Antibodies/biosynthesis , Humans , Immunity, Innate , Interleukin-2/pharmacology , Lymphocyte Activation/drug effects , Male , Middle Aged , Recombinant Proteins/pharmacology , T-Lymphocytes/drug effectsABSTRACT
Excretory-secretory products (ES), collected from in vitro cultures of adult Nematospiroides dubius, were examined for proteolytic enzyme activity. ES enzymes had a pH optimum of 8.0 and their activity was sensitive to serine-proteinase inhibitors. Three SDS-resistant proteases were identified in ES at molecular weight (mol. wt) 200,000, 105,000 and 48,000 by incorporating substrates into the matrices of sodium dodecyl sulfate-polyacrylamide electrophoresis (SDS-PAGE) gels.