Failure of parental T cells to restore T-cell deficient F1 mice.

The ability of normal, parental type T cells to initiate an immune response and to generate memory T cells in T-cell deficient F1 mice was investigated using two types of F1 recipients: Congenitally athymic (nude) mice and thymectomized, lethally irradiated, syngeneic bone marrow reconstituted (TIR) mice. In contrast to normal syngeneic T cells, normal parental type T cells elicited neither immune response nor memory T cells in F1 T-cell deficient mice. Parental T cells were ineffective even when obtained from chimeric donors tolerant to the second parental type transplantation antigens and normal, parental T cells did not counteract the restorative activity of F1 T cells in F1 T-cell-deficient recipients. These two latter findings exclude a suppression due to an ongoing GVH reaction as a possible cause for failure of parental T cells to restore F1 T-cell-deficient mice.