Elution of an Incomplete Type of Antibody from the Erythrocytes in Acquired Haemolytic Anaemia.

A notable advance in the study of the haemolytic anaemias was made by Boorman, Dodd, and Loutit (1946), who showed that it vwas possible to differentiate between the congenital and acquired types of acholuric jaundice by submitting the washed erythrocytes from these patients to the action of an anti-human globulin serum (Coombs and others, 1945). The erythrocytes of 17 patients with congenital familial type were not agglutinated under these conditions, whereas those from seven patients with clinically acquired type were all agglutinated and so presumably had antibody globulin adsorbed to their surface. No free antibody was found in the serum from these cases, probably because all circulating antibody was fixed on the erythrocytes. During a personal study of six patients with acquired haemolytic anaemia the washed erythrocytes of all cases were found to agglutinate strongly with an anti-human globulin serum. Corresponding antibody of the " incomplete " type (Race, 1944) was not, however, found free in the serum of any of these cases, although cold agglutinin of low titre was present in the serum of two of them. In order to elucidate further the nature of the antibody adsorbed upon the erythrocyte in these patients it seemed necessary to attempt to dissociate the antibody from its union with the erythrocyte. After a number of tentative experi-cments a satisfactory technique for this purpose was elaborated, and the results presented provide direct evidence that an antibody of " incomplete " type is adsorbed on the erythrocytes in these cases. Some in vitro properties of this antibody were also investigated.