Gamma-globulin Inhibits Superantigen-induced Lymphocyte Proliferation and Cytokine Production

摘要

Background: High-dose pooled human immunoglobulin (PHIG) treatment is sometimes effective in superanti-gen related inflammatory diseases, such as toxic shock syndrome and Kawasaki disease. Neutralizing antibody to superantigen might provide protection, but antigen independent immune regulation of PHIG is also a proposed mechanism. Methods: Staphylococcal enterotoxin B (SEB)-specific IgG antibody in PHIG products (Venoglobulin IH~? was detected by ELISA. The suppressive effect of PHIG or its fragments on proliferation and cytokine (IL-4 and IFN-gamma) production from SEB-stimulated peripheral blood mononuclear cells was examined. Results: SEB-specific IgG was detected in PHIG products. PHIG (6.25-25 mg/ml) suppressed SEB-induced proliferation and cytokine production in a dose-dependent manner. Fab and F (ab') 2 fractions of PHIG also suppressed the responses, but depletion of SEB-specific antibody from PHIG did not affect the inhibitory effects. The Fc fragment of PHIG also showed partial, but significant suppression. Conclusions: These data suggested the possibility that PHIG suppressed SEB-induced proliferation and cytokine production by some mechanisms independent of the presence of neutralizing antibody.