Recovery of Contact Hypersensitivity Responses Following Murine Bone Marrow Transplantation

Bone marrow transplantation (BMT) is often followed by significant morbidity and mortality due to protracted immunodeficiency. We have hypothesized that the bone marrow-ablative regimen may delay the recovery of normal immune function following transplantation by impairing the interaction of host endothelial cells with circulating graftderived lymphocytes. This report compares the relative effects of busulfan (an alkylating drug) and gamma-irradiation on the tissue-specific localization potential of lymphocytes and the eventual recovery of immune function within syngeneic murine transplant recipients. Localization of normal lymphocytes into peripheral lymph nodes of irradiated BMT recipients was markedly less (<50%) than in busulfan-treated or normal mice over the first 2 months post-BMT. This finding correlated with irradiation-induced