The effect of naturally occurring Rh antibodies on the survival of serologically incompatible red cells.

Investigations on six males with naturally occurring Rh antibodies are described. In two subjects in whom the antibody (one anti-E and one anti-D) could be detected only by a two-stage papain technique, the survival of incompatible red cells was normal. In the remaining four subjects, the antibodies (two anti-E and two anti-D) could be detected by the indirect antiglobulin test and, in these, incompatible red cells were destroyed at an accelerated rate; in two of the subjects, 75-99% of the cells were cleared within 24 h; in the other two, 50% of the cells were cleared within 24 h and the remaining cells were cleared far more slowly. All six antibodies were mainly or wholly IgG; a clear-cut immune response was observed in only one case.