Fc receptor-mediated binding and ingestion of immunoglobulin G-coated erythrocytes by the epithelium of the posterior ciliary processes: an in-vitro study.

In the present in vitro study of intact ciliary processes, we observed, under differential interference microscopy, IgG inhibitable selective epithelial adherence and internalization of IgG-coated erythrocytes (E-IgG). Unequivocal evidence of ligand ingestion was obtained with a fluorescence technique which employed glutaraldehyde-fixed opsonized erythrocytes. Neither adherence nor internalization were seen when uncoated erythrocytes, IgM, or F (ab')2-coated erythrocytes were substituted for E-IgG in the incubation media. These in-vitro studies demonstrated that the cell membranes of this epithelium exhibit a specific receptor for IgG which may clear the aqueous of IgG aggregates and be associated with the exocytosis of soluble mediators of inflammation.