Anti-HL-A Immunization after Repeated Haemodialysis in Relation to Patients’ HL-A Types

Sera from 47 patients immunized mainly by multiple transfusions during haemodialysis were studied by the lymphocytotoxicity test (LCT) and the platelet complement fixation test (PICF). The HL-A specificities of the observed antibodies were compared with the HL-A antigens present in the immunized subjects. The inhibition of the production of antibodies against certain antigens in the presence of cross reacting antigens in the immunized individuals was studied by a method using “Bayes’ theorem”. This inhibition was only partial for the antibodies detected by LCT in contrast to those found by PICF. The comparison of both techniques lead to the conclusion that this type of inhibition did not completely prevent the production of antibodies against a cross reacting antigen but it decreased the frequency and intensity of the response against the antigen.