CHRONIC KIDNEY ALLOGRAFT REACTIONS IN RATS

Chronic rejection of orthotopic kidney allografts occurred between inbred Fischer and Lewis rats with survival times up to 48 weeks in Fischer → Lewis combinations and greater than 60 weeks in Lewis → Fischer combinations. Lewis recipients of Fischer kidney grafts showed prolonged survival in spite of repeated, prompt rejection of subsequent Fischer skin grafts. In otherwise normal Lewis recipients, chronic rejection of Fischer kidney allografts was characterized by minimal loss of renal function, slow but progressive destruction of kidney parenchymal tissue, and persistent alloantibody production until the terminal stages of rejection. Survival and function of Lewis → Fischer kidney allografts were similar to that of isografts, however; there was minimal cellular infiltration and destruction of the allograft compared to the reciprocal combination. Lewis recipients, sensitized by Fischer skin or kidney grafts, showed accelerated rejection of subsequent Fischer skin grafts. Moreover, Lewis rats sensitized with Fischer skin grafts rejected subsequent Fischer kidney grafts in an accelerated manner. These findings demonstrated the reciprocal immunogenicity and vulnerability of kidney and skin allografts in these strain combinations. Nevertheless, kidney allografts between Lewis and Fischer rats had prolonged survival times, even though skin allografts were rejected promptly. Differential susceptibility to immunological enhancement mediated by humoral alloantibodies probably contributed to the disparate survival times observed. Functional, histological, and serological evidence support, this hypothesis. © 1969 by The Williams and Wilkins Co.