Pathological changes in F1 hybrid mice following transplantation of spleen cells from donors of the parental strains

Abstract

It has already been reported by one of us (Boyse, 1959) that intraperitoneal transplants of spleen cells from A strain donor mice that had been immunized against C57BL strain tissues were invariably lethal to hosts of the F₁ (C57BL×A) constitution.

In this report an account is given of the pathological changes in F₁ hybrid hosts that have received intravenous or intraperitoneal transplants of spleen cells from parental strain donors, with particular reference to lethal transplants. Here the outstanding features are splenomegaly, wasting, progressive histiocytosis in the spleen and lymph nodes, disappearance of lymphoid tissue, focal necrosis of the spleen and cellular infiltrations round the hepatic vessels. Following transplantation by the intraperitoneal route there are also severe pancreatic lesions associated with fat necrosis and ascites.

Differential (donor/host) cell counts of host spleen cell suspensions indicate that the spleen may be virtually replaced by donor cells, the majority of which are histiocytes. Erythropoietic function is progressively supplanted by donor tissue.

Similar, but reversible and less extensive changes occur with other (non-lethal) donor/F₁-host combinations. These hosts do not waste and the proportion of donor cells included in the host spleens falls until their detection, by present methods, is no longer possible.