AUTOANTIBODIES MIMICKING ALLOANTIBODIES

A patient with myelofibrosis, who has produced many red blood cell autoantibodies, is described. Although the patient is phenotypically R1R1 (CDe/CDe), eluates made from his red blood cells have consistently contained what appeared to be anti-E, and more recently another antibody that appeared to be anti-c. In in vitro experiments the anti-E and anti-c antibodies can be totally adsorbed by E-negative and c-negative red blood cells, respectively. The 2 antibodies have quite different specificites from those indicated by simple antibody identification studies, both are more closely related to the anti-Hr series of antibodies than to anti-E or anti-c.