Abstract: | Allogenic transplantations of bone marrow or spleen cells were carried out on rabbits treated with cyclophosphamide. About 50% of the recipients developed chimerism of peripheral blood cells. Chimerism was a passing phenomenon prevailing from 14 to 180 days after grafting. A phenomenon indicating that not all cell lines develop after transplantation from the donor stem cells, was observed. This phenomenon has been called "restricted chimerism". The GvH reaction was of a chronic type. Relative spleen weights were significantly increased in animals receiving the spleen cell grafts, but not in animals receiving bone marrow grafts. A direct positive erythrocyte Coombs test was found in almost all graft recipients. In addition cytotoxic autoantibodies against lymphocytes were present in sera of about 20% of the recipients. |