Effect of transfusion on immune function in a traumatized animal model.

Blood transfusions repeatedly have been shown to prolong allograft survival, probably by stimulating suppressor T lymphocytes. The effects of transfusions on immune function in traumatized patients has not previously been investigated. We investigated the effects of transfusions on the immune system using a burned rat model. The transfusions were found to have no effect on the white blood cell counts, differential cell count, or neutrophil migration and bactericidal index. Those animals that received transfusion did exhibit impaired cell-mediated immunity and macrophage migration. Blood transfusions seem to increase further the immunosuppression seen with trauma and surgery.