Alanine inhibits cytotoxic responses: its production by different tumor cell lines explains differences in their immunogenicity.
The immunogenicity of a mutagenized subline (ESb-D) of the weakly immunogenic lymphoma L5178Y ESb has been analyzed. The ESb-D cells were shown to be strongly immunogenic by various criteria, including the in vivo priming for an in vitro secondary cytotoxic response. The ESb parent line was only weakly immunogenic by all criteria tested. Culture supernatants from ESb cells were found to contain high concentrations of L-lactate and alanine. ESb-D supernatants contained also L-lactate but little alanine. L-alanine in combination with L-lactate was found to be immunosuppressive; ie, it inhibited the in vivo priming for secondary cytotoxic responses.
D000409:Alanine / Q000276:immunology* / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005260:Female; D007165:Immunosuppression Therapy; D007773:Lactates / Q000494:pharmacology; D007940:Leukemia L5178 / Q000276:immunology*; D007942:Leukemia, Experimental / Q000276:immunology*; D051379:Mice; D008811:Mice, Inbred DBA; D016685:Mitomycin; D008937:Mitomycins / Q000494:pharmacology
D007773:Lactates; D008937:Mitomycins; D016685:Mitomycin; D000409:Alanine