Listeria monocytogenes infection in beta 2 microglobulin-deficient mice.

beta 2 microglobulin-deficient mice, in which the beta 2m gene has been disrupted by homologous recombination, lack functional CD8 T cells and are able to contain but not resolve an intravenous immunizing inoculum of Listeria monocytogenes. We present evidence that compensatory immunity in such immunodeficient mice was mediated by a population of gamma delta T-cell receptor-positive cells; in contrast, neither CD4 cells nor natural killer cells appeared to play any part in this process. These data further support the emerging hypothesis that immune cells other than those bearing the alpha beta T-cell receptor type can also play an important role in acquired resistance to listeriosis.