Immune competency of nude mice bred from homozygous and heterozygous mothers.

The immune competency of nude mice born from matings of strictly homozygous nu/nu X nu/nu parents was compared to nude mice derived from the breeding of either heterozygous nu/+ mothers by nu/nu fathers or nu/nu mothers by nu/+ fathers. Spleen cells from nude mice born from heterozygous mothers had significantly higher levels of beta-bearing cells than mice born from homozygous mothers and were minimally stimulated by the T cell mitogens Con A and PHA-P. In contrast, there were no detectable maternal influences when survival of skin allografts and primary sheep red cell stimulation were studied. Homing studies of 51Cr thymocytes in term-pregnant nude mice suggest that the enhanced T cell characteristics of nude mice born of nu/+ mothers are caused in part by placental transfer of allogeneic maternal lymphocytes.