title: Effects of different fractions of Corynebacterium parvum on the cytotoxic T-cell response to alloantigens in mice.
abstract: The effects of several biochemically derived fractions of Corynebacterium parvum and chemically treated intact organisms on the generation of cytotoxic T-lymphocytes (CTL) were assessed in a tumor allograft model with the use of C57BL/6 and DBA/2 mice. The acid-modified, active and inactive fragmented preparations and pyridine extract and residue were all capable of inhibiting primary spleen cell allocytotoxicity. Only the active fragmented, pyridine residue and unfractionated preparations caused splenomegaly and prevented the secondary in vitro generation of CTL. Periodate treatment, acid modification, and pyridine extraction abrogated the ability of C. parvum to activate suppressor macrophages. Although incapable of activating suppressor macrophages, the phenol and pyridine extracts significantly enhanced suppressor T-cell activity. The effect of whole C. parvum organisms on T-cell-mediated cytotoxicity is thus extremely complex and due to the direct activation or inhibition of various cell types that interact with each other.
mesh_terms: D000818:Animals; D003602:Cytotoxicity, Immunologic; D005260:Female; D007114:Immunization; D007519:Isoantigens / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D011425:Propionibacterium acnes / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D007519:Isoantigens