Effects of sublethal irradiation on patterns of engraftment after murine bone marrow transplantation.

Attempts to reduce the toxicity of hematopoietic stem cell transplantation have led to the use of various immunosuppressive, yet nonmyeloablative preparative regimens that often include low-dose irradiation. To determine the effects of low-dose irradiation on the dynamics of donor cell engraftment after bone marrow transplantation (BMT), we coupled standard endpoint flow cytometric analysis with in vivo longitudinal bioluminescence imaging performed throughout the early (<10 days) and late (days 10-90) post-BMT periods. To exclude the contribution of irradiation on reducing immunologic rejection, severely immune-deficient mice were chosen as recipients of allogeneic bone marrow.