Characterization of a soluble suppressor of human B cell function produced by a continuous human suppressor T cell line. II. Evidence for suppression through a direct action of CTC-SISS-B on human B cells.
CTC-SISS-B is an antigen-nonspecific suppressive lymphokine elaborated by an interleukin 2-dependent suppressor T cell line that produces noncytotoxic inhibition of human B cell but not T cell function. Like SISS-B, a soluble suppressive lymphokine present in the supernatants of Con A-activated peripheral blood T cell cultures, CTC-SISS-B is of 60,000 to 90,000 m.w., and its action is blocked by the simple sugar L-rhamnose. CTC-SISS-B inhibits human B cell Ig production and proliferation through a direct interaction with human B cells rather than through indirect effects on immunoregulatory T cells or monocytes. CTC-SISS-B suppression occurs through inhibition of an early event(s) in B cell activation since proliferation and Ig production by established human B cell lines are not inhibited by this lymphokine. Despite sharing many biochemical and biologic properties, CTC-SISS-B and gamma-interferon appear to be distinct mediators.
D001402:B-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D002478:Cells, Cultured; D006801:Humans; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008222:Lymphokines / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D009000:Monocytes / Q000276:immunology; D011043:Pokeweed Mitogens / Q000037:antagonists & inhibitors; D013491:Suppressor Factors, Immunologic; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D008222:Lymphokines; D011043:Pokeweed Mitogens; D013491:Suppressor Factors, Immunologic