The early posttransplant prognosis of acute renal allograft rejection as determined by detection of cytotoxic antibodies to lymphoid B cell lines.

We have studied serial samples of pretransplant and posttransplant sera for cytotoxic antibodies to lymphoid B cell lines (LCL) in 45 renal allograft recipients. A total of 48 rejection reactions occurred in 31 patients. A comparison of each patient's most reactive posttransplant serum showed a significantly higher reactivity in the ten patients with early allograft failure when compared with the 21 patients with reversible rejections and the 14 patients who had no rejections. Rejection reactions were easily differentiated by comparing the change in cytotoxic reactivity to LCL of recipients' sera drawn at the time of a rejection episode with the reactivity of their pretransplant sera. In 32 rejections considered non-antibody-associated cytotoxic reactivity of recipients' sera to LCL either decreased or remained essentially unchanged during the rejection. In 16 rejections considered antibody-associated the recipients' sera drawn during the rejection episode showed an increase in cytotoxic reactivity ranging from 40% to 100%. Response to antirejection therapy and three month graft survival had a significant correlation with changes in LCL antibody reactivity during a rejection. Only two of the 32 rejections considered non-antibody-associated failed to reverse compared with eight of the 16 antibody-associated rejections (P less than .001). Graft survival at three months in patients with non-antibody-associated rejections was 90% compared with 27% in the 11 patients who had antibody-associated rejections (P less than .001) Other parameters possibly related to the severity of a rejection reaction or to early allograft prognosis did not differ appreciably between the two types of rejections. This included the time posttransplant to the first rejection episode, the number of patients with multiple rejections in the first three months, and rejections requiring dialysis therapy. Determination of a change in cytotoxic reactivity to LCL during a rejection reaction enables one to predict the response to antirejection therapy and early allograft prognosis. This may ultimately be useful in selecting different types of antirejection therapy for individual patients.