Binding of complexes of IgG antibody and particulate antigens to Fc receptors present on the surface of chicken red cells

Abstract

When chicken red cells were mixed at 4°C for 18 h with immune complexes of DNP— Salmonella typhi and anti-DNP non-precipitating sheep IgG 1 antibody, rosettes were formed via the Fc receptors present at the surface of the erythrocytes. The formation of rosettes could be competitively inhibited by pretreatment of the cells with human IgM·7S, aggregated IgG for Fcμ, all of which were previously shown to bind to the Fc receptors. Incubation of the rosettes at 37°C resulted in capping of the immune complexes, followed by their detachment from the red cell membrane. The cells treated in this way were able to form rosettes again. Blastogenesis-like appearance of the cells was observed during the rosetting phenomenon, and disappeared after capping and detachment of the immune complexes. The possible participation of chicken red cells, and probably other nucleated red cells, in depuration mechanisms of immune complexes is suggested.