title: Contra-IL 2; a suppressor lymphokine that inhibits IL 2 activity.
abstract: Suppressive activity of culture supernatant of AS-9 (AS-9 CS), a T cell hybridoma line that was derived from fusion of BW5147 thymoma and splenic T cells of anti-lymphocyte serum-treated C3H mice, was analyzed. AS-9 CS inhibited allogeneic cytotoxic T lymphocyte (CTL) generation as well as T cell proliferation to alloantigens and mitogens, but failed to inhibit B cell response to lipopolysaccharide or growth of tumor and fibroblast cells. Although addition of AS-9 CS to the allogeneic sensitization culture as late as on day 2 of incubation resulted in maximal inhibiton of CTL generation, removal of AS-9 CS on day 3 of incubation abolished its inhibitory effect. Addition of purified IL 2 together with AS-9 CS to the allogeneic sensitization cultures only partially abrogated the suppression. Experiments with IL 2-dependent cytotoxic T cell line (CTLL) showed that AS-9 CS suppressed the IL 2-induced proliferation of CTLL. Preincubation of AS-9 CS with CTLL removed its inhibitory effect on CTL generation. These results indicate that AS-9 CS interferes with the mechanism of T cell activation by IL 2. On this basis, AS-9 CS was named contra-IL 2.
mesh_terms: D000818:Animals; D002455:Cell Division; D002474:Cell-Free System; D005347:Fibroblasts / Q000166:cytology; D006825:Hybridomas / Q000032:analysis; D007108:Immune Tolerance; D007376:Interleukin-2 / Q000378:metabolism*; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008805:Mice, Inbred A; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D013491:Suppressor Factors, Immunologic / Q000502:physiology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D013945:Thymoma / Q000473:pathology; D013997:Time Factors
chemical_list: D007376:Interleukin-2; D013491:Suppressor Factors, Immunologic