Renal transplantation in rabbits. 8. The relationship between lymphocytotoxic antibodies, renal IgG deposits and the renal allograft reaction in rabbits sensitized by multiple skin grafts.

Abstract

The development of lymphocytotoxic antibodies during sensitization by two to nine skin grafts from the same donor has been followed weekly or biweekly for up to 6 months. A total of 438 serum samples from 46 rabbits sensitized with 250 skin grafts were studied. Lymphocytotoxic antibodies were demonstrable in all but four rabbits. Peak activity was generally reached 8 weeks after the first skin graft and after transplantation of from 4 to 6 skin grafts. Prolongation of the period of sensitization and increase in the number of skin grafts did not result in higher antibody titre or a more constant antibody level, but sera reacted with lymphocytes from a greater number of rabbits. Early appearance of neutrophils or of multiple glomerular microthromboses in small intrarenal blood vessels or glomerular capillaries, indicating severe allograft reaction, were observed in 17 out of 43 primary kidney allografts into presensitized rabbits. A further 7 allografts were removed 2–6 hours after re‐establishment of blood circulation because of clinical signs of rejection, but these grafts showed no histologic lesions. Neither the titre of cytotoxic antibodies at the time of operation nor the maximum titre of antibodies found during the whole observation period were correlated to the severity of the allograft reaction. Long term sensitization did not result in a significantly higher frequency of severe allograft reactions than did short term sensitization.