Marrow Engraftment by Allogeneic Leukocytes in Lethally Irradiated Dogs

Infusion of white blood cells separated from peripheral blood produced allogeneic bone marrow engraftment in lethally irradiated dogs. Approximately 100 x 10⁹ leukocytes obtained from a single donor over an 8-day period were adequate to establish marrow repopulation. Marrow engraftment was indicated by rising blood count, marrow histology, and, in one instance, cytogenetic studies. Marrow grafts were associated with a severe secondary syndrome. Survival was prolonged with methotrexate.