Age-related factors in cyclosporine-induced syngeneic graft-versus-host disease: regulatory role of marrow-derived T lymphocytes

e mechanism carried over with mature T cells in the marrow inoculum, the premise in these experiments was to evaluate the autoreactive potential of the lymphocytes in animals grafted with marrow and mature T cells before clonal activation (due to the presence of C&A) and the subsequent transfer into an environment with a reduced or absent host resistance mechanism. Transfer of splenocytes (5 x 107) from C&A treated recipients grafted with marrow plus 10' T lymphocytes (from animals 6 mo of age) harvested on day 30 into secondary recipients did not result in adoptive transfer of disease (0/6). However transfer of spleen cells (5 x 107) from CsAtreated animals grafted with marrow but in the absence of T cells resulted in the development of SGVHD in the secondary recipients (5/6).