Listeria monocytogenes specific T-cell lines and clones

Evidence is summarized to suggest that both CD4 and CD8 T cells and both helper and cytolytic T cell functions are involved in protective immunity to infection with the intracellular bacterium, Listeria monocytogenes. This suggestion is based on the following findings obtained with T cell lines and clones from L. monocytogenes infected mice: L3T4+ (CD4) T cells produce multiple lymphokines after antigen stimulation in vitro; Lyt2+ (CD8) T cells lyse L. monocytogenes primed macrophages; L3T4+ (CD4) T cells also lyse L. monocytogenes primed macrophages provided the latter express Ia-molecules; Lyt2+ (CD8) T cells secret Interferon-gamma provided that exogenous Interleukin-2 is supplied. Furthermore, both L3T4+ (CD4) and Lyt2+ (CD8) T cell lines can confer a certain degree of adoptive protection upon naive recipient mice.