Allograft immunity to histocompatibility and organ-specific antigens.

An experimental model has been developed in the dog in which a renal allograft was placed in the neck, leaving one of the dog's own kidney in situ. Five nonimmunosuppressed pairs of dogs have been studied by using the leucocyte migration test (LMT) as an in vitro measure of cell-mediated immunity. Antigen preparations from leucocytes, kidney, liver, and skeletal muscle from both the kidney donor and the recipient were used in the LMT in order to study responses against transplantation and organ-specific antigens. Inhibition of migration with donor-specific leucocyte and kidney antigens was detectable prior to clinical evidence of rejection, which was confirmed histologically. Concurrently, inhibition was also observed with autologous kidney antigen and histological damage was noted in the recipient's own nontransplanted kidney, accompanied by increasing proteinuria. Autologous serum withdrawn daily and added to the test culture medium abolished the inhibition of migration, thus suggesting the development of blocking factor.