Further studies on the relationship of anti-Ena and anti-Wrb in warm autoimmune hemolytic anemia.

The red blood cell eluates of two patients with warm autoimmune hemolytic anemia (AIHA) were found to have anti-dl and anti-Wrb in a study of 150 individuals with positive AHG tests.7 In that series 39 per cent of AIHA cases had anti-Wrb as part of the autoantibody specificity. The eluates of these two patients were of further interest since they showed weaker reactions with En(a-) cells than with En(a+), Wr(a+b-) cells. Further absorption of the eluates confirmed a second component that reacted with the En(a+), Wr(b-) cells but not the En(a-) cell, interpreted as autoanti-Ena. In one of the cases anti-Ena was recovered from the En(a-) absorbing cell although these cells were not agglutinated by the autoantibody. This effect was not due to polyagglutinability, the Matuhasi-Ogata phenomenon or the decreased sialic acid content of the En(a-) red blood cell membranes and remains unexplained.