Graft-versus-host disease in murine bone marrow transplantation. I. Modification of GVHD by preimmunization of recipients with spleen cells of primary recipients undergoing GVHD.

Lethally irradiated (1000 rad) CBA/J mice were transplanted with anti-Thy 1 treated BALB/c bone marrow. Under these conditions, we uniformly observed the development of pathology suggestive of acute graft-vs.-host disease (GVHD), i.e. weight loss, diarrhoea, hypogammaglobulinemia and thymic hypoplasia. If, 2 wk before irradiation, the recipients were preimmunized with spleen cells taken from mice undergoing acute GVHD, these symptoms were avoided. Instead, such animals seemed to show long term survival either with or without signs of chronic GVHD (hypergammaglobulinemia, splenomegaly, lymphoid hyperplasia). The ability to show long term survival with bone marrow allografts was dependent upon successful immunization of the recipient mice. Long term survivors contain a splenic population not bearing detectable host MHC antigens, which can elicit a memory anti-host cytotoxic response from a population of quiescent donor lymphocytes previously immunized in vitro against host MHC antigens.