A cell surface ELISA for detection of blood group antibodies- on anti-ABO and -MN blood group antibodies.

A cell surface ELISA method was employed for detection of polyclonal anti-A, -B, -M and -N, and monoclonal anti-M and -N antibodies. Native erythrocyte membranes or those fixed with glutaraldehyde (GA) were used as solid phase antigen in the ELISA method. In detection of anti-A and -B, and of monoclonal anti-M and -N antibodies, the method used here on the plates with erythrocyte membranes without fixation of GA had approximately 20-40 fold higher sensitivity than the hemagglutination test, but polyclonal anti-M and -N antibodies almost equally bound on the plates coated with unfixed group-M erythrocyte membranes. Anti-A, -B, and monoclonal anti-M antibodies were detected to the same extent in the plates with fixed erythrocyte membranes as in the plates coated with unfixed erythrocyte membranes, but binding of monoclonal anti-N antibody to group-N fixed erythrocyte membranes was not observed. In regard to the eluted antibody, the present cell surface ELISA method had an advantage over the hemagglutination test in detection of anti-A, -B, and monoclonal anti-M antibodies. Binding of monoclonal anti-N antibody to group-N antigen on the group-N or -MN bloodstains was not observed in both the present ELISA and the hemagglutination test. The results obtained indicate that present ELISA method is very useful to medicolegal practice.