Alloreactive lymphocytes from T cell receptor (β-chain) transgenic mice do not mediate a graft-versus-host reaction

The injection of mature T cells into a tolerant or immunocompromised allogeneic host animal produces a graft versus host response (GVHR) that can result in splenomegaly, immunosuppression and death of the host animal. We demonstrate here that lymphocytes from T cell receptor β-chain (TCR-β) transgenic mice, in which the expression of the transgene inhibits endogenous β- and γ-gene rearrangements and thus causes abnormal T cell development, are unable to mediate a GVHR. The GVHR was measured after the injection of lymphocytes from transgenic mice into normal F₁ mice and also after transplantation of bone marrow and lymphocytes from transgenic mice into lethally irradiated F₁ recipients. In both systems, cells from transgenic mice failed to produce a significant GVHR. Cells from the transgenic mice were able to recognize the foreign histocompatibility Ag of the host in vitro and in vivo although the transgenic mice rejected skin grafts more slowly than controls. Thus, lymphocytes from transgenic mice were unable to produce a GVHR despite the presence of alloreactive T cells. These results suggest that lymphocytes from TCR-β transgenic mice fail to mediate a GVHR either because lymphocytes with a single transgenic TCR-β chain have a limited ability to recognize allogeneic cells in vivo or because the transgenic mice lack lymphocyte subsets that are important for the mediation of a GVHR.