Immunogenetic Studies on X-Irradiated Mice Treated with Homologous Hematopoietic Cells<xref ref-type="fn" rid="FN1">2</xref>

Abstract

ing place in x-irradiated mice treated with homologous hematopoietic cells. The results of experiments with hybrid combinations of hosts and donors suggest that the grafted cells react imnnunologically against the isoantigens of the irradiated recipient. The production of antiC3H agglutinins by the inoculated C57BL cells was demonstrated by the transfer of lymph nodes from the irradiated and treated C3H mice back to normal C57BL mice. The ''cytotoxic'' anti-host immune reaction responsible for the lethal ''secondary disease'' of homologously treated mice was demonstrated by the passive transfer of tramsplantation immunity produced by the isoantigens of the recipient. Bone marrow from irradiated C3H mice treated with C57BL cells conferred on other irradiated C3H mice a much shorter survival time than normal C57BL cells. It is concluded that the cells from the C57BL-treated C3H donors were immunologically activated by the primary C3H hosts and killed the secondary C3H hosts through an immunologically secondary response. Thc mortality of nvice treated with mixed embryonic isologous and adult homologous cells indicates that even if, theoretically, a delayed antigraft response is feasible, the graft antihost response has a domin:int role in the immunogenetic incompatibility. An attempt to overcome this incompatibility was made by injecting irradiated C3H micemore » with fetal C57BL liver cells. The increased survival time obtained in this experiment may suggest a method for the application of the principles of biological protection to animals of genetically heterogeneous populations. (auth)« less