Transmission of an Mls-1a-like superantigen to BALB/c mice by foster-nursing on F1 Mls-1bxa mothers. Sex-influenced onset of clonal deletion.

Abstract

Foster nursing of BALB/c (Mls-1b) mice on (BALB/cxAKR/J)F1 and (BALB/cxDBA/2)F1 (Mls-1bxa), but not on (BALB/cxC57Bl/6)F1 or (BALB/cxC3H/He)F1 (Mls-1bxb mothers, induced the progressive deletion of V beta 6+ and V beta 8.1+ T cells in 50% of the litter. The onset of this Mls-1a-like clonal deletion was markedly sex-influenced, being earlier in females (8-10 wk of age) than in males (32 wk). In both sexes, CD4+ V beta 6+ cells were more affected than CD8+ V beta 6+ cells. Decreases in the percentage of V beta 6+ cells were detected simultaneously in the thymus, lymph nodes, and peripheral blood. Preceding clonal deletion, functional unresponsiveness of CD4+ T cells to Mls-1 a Ags and to anti-V beta 6 Abs could be detected in most young male and female mice. The transmission of the Mls-1a-like superantigen through foster-nursing on (BALB/cxAKR/J)F1 mice correlated with the presence in milk of the mouse mammary tumor virus envelope protein gp52.