Co‐expression of different types of Fc receptors on murine peritoneal macrophages

Abstract

Simultaneous expression of particular immunoglobulin Fc receptors (FcR) was studied on the plasma membranes of murine peritoneal macrophages. This was facilitated by the use of sheep red blood cells (SRBC) and/or synthetic microspheres coated with monoclonal antibodies of different isotypes. It was concluded that a majority of macrophages bear more than one type of FcR; macrophages bearing at least three types of FcR were present in the peritoneal cavity; macrophages bearing Fc mu R did not bind IgE, IgA or IgG; all macrophages bearing Fc alpha R also expressed Fc gamma 2bR, Fc gamma 3R and Fc epsilon R; all macrophages bearing Fc epsilon R also expressed Fc gamma 2bR and Fc alpha R. Except for Fc alpha R, essentially equivalent numbers of FcR-bearing macrophages were detected when antibody-coated SRBC or polymeric microspheres were used. Simultaneous applications of these reagents permitted the most detailed and direct investigations yet performed of multiple FcR expression on individual cells.

Murine Fcγ receptor proteins: identification of a previously unrecognized molecule with a monoclonal antibody (12‐15)

“…In the present report we have studied in detail the specificity of a mAb (12)(13)(14)(15) which recognized an antigen that is associated with the acquisition of adhesiveness and decreased malignant potential of metastatic ESb cells [22]. The results presented here indicate that the epitope for mAb 12-15 resides on molecules known as FcR.…”

“…Adhesive growth was strongly associated to decreased malignant potential of the cells [20,22,231. During the course of our studies we characterized a mAb (12)(13)(14)(15) displaying strong reactivity to the adhesion variant (ESb-MP) and weak binding to ESb cells. Here we show that the 12-15 antibody recognizes an epitope on FcyR.…”