Anti-B lymphocytotoxins in renal-allograft rejection.

To determine the possible role of the B lymphocyte alloantigen system in renal-transplant rejection, we examined serum specimens from 81 allograft recipients for cytotoxic activity against a panel of normal B lymphocytes. Specimens from 22 of 25 recipients undergoing allograft rejection demonstrated strong B-lymphocyte cytotoxicity whereas only 13 of 56 recipients with normal allograft function showed similar B lymphocyte cytotoxocitiy (P less than 0.0001). In the serum samples of recipients with graft rejection who were followed sequentially, B-lymphocyte cytotoxicity preceded or was concurrent with the onset of functional impairment. The results show that anti-B-lymphocyte antibodies are associated with rejection, but it is quite possible that they are the products of rejection rather than the cause.