Correlation of humoral immunity to Lewis blood group antigens with renal transplant rejection.

Recent studies suggest that the Lewis blood group antigens are important for human renal transplantation. A possible mechanism by which Lewis blood group incompatibility could influence allograft rejection was investigated by measuring Lewis antibodies in sera from renal transplant recipients and appropriate controls using conventional hemagglutination and a sensitive and specific kinetic enzyme-linked immunosorbent assay (k-ELISA). The two methods yielded identical results with 14 positive control sera known to contain Lewis antibodies and with 43 sera from negative controls. Antibody was not detected in 16 Lewis-positive transplant patients. However, antibody was detected by k-ELISA in 4/11 Lewis-negative transplant candidates and in 8/8 Lewis-negative recipients of Lewis-incompatible grafts. All 8 grafts were rejected. The one Lewis-negative recipient of a Lewis-negative graft did not develop Lewis antibody nor reject his graft. Of the 12 renal patients in whom antibody was detected by k-ELISA, in only 4 was antibody also demonstrable by hemagglutination. These results indicate that hemagglutination may not be sensitive enough for antibody detection and that Lewis antibodies may play a role in renal allograft rejection.