Specificity of Phagocytosis as It May Relate to Antibody Formation

Abstract

The more distant the genetic relationship between erythrocyte and phagocyte, the greater the per cent phagocytosis. Unabsorbed mouse serum contained phagocytosis-enhancing factors; however, erythrocytes from more distantly related species were phagocytized in the absence of these serum factors. Erythrocyte specific antisera increased the degree of phagocytosis. Simultaneous incubation of two different species of erythrocytes with phagocytic cells demonstrated that phagocytosis is highly selective with regard to erythrocyte antigens. In the absence of type specific antisera, the more distantly related erythrocytes were preferentially engulfed. This selectivity could be modified by the addition of specific erythrocyte antibodies. Under conditions in which one erythrocyte was phagocytized maximally, small numbers of cells retained a specificity for, and engulfed exclusively, the second type erythrocyte. There was an apparent exclusion of a second type erythrocyte after engulfment of the first when one type of erythrocyte was incubated for 30 min before the second type was introduced. Only a small percentage of phagocytic cells engulfed two types of erythrocytes. The possible significance of phagocytic cells in antibody formation has been discussed.