The coating of erythrocytes with detergent-solubilized molecules: a general method for improved coupling of antigens and antibodies

A method is described by which different antigens and antibodies in solutions containing deoxycholate (DOC) may be coated to glutaraldehyde (GA)-fixed erythrocytes. This method, based on the use of CrCl₃, yields erythrocytes which preserve the antigenicity and antibody activity of the coated molecules and can thus be applied to various assays in which indicator red cells are required. The sensitivity of the assays increases when these red cells are used. The cells form rosettes with the appropriate receptor positive cells. They sediment in Ficoll-Isopaque as do native erythrocytes and do not aggregate spontaneously even when coated at very high or low concentrations of CrCl₃ or antigen. This coupling method, which is performed in the presence of DOC, and which requires only a small amount of antigen, is proposed for the coupling of cell membrane dissolved antigens.