Exclusive binding of immunoglobulin to Fc gamma receptors on macrophages in 3-methylcholanthrene-induced murine tumors.
Immunogenic, chemically induced, murine tumors generally are infiltrated with large numbers of Fc gamma receptor (Fc gamma R)-positive cells, most of which are mononuclear phagocytes. This study demonstrates in inbred C3H/HeN mice that such immunogenic tumors contain large amounts of cell-bound immunoglobulin (Ig) and that, within the sensitivity limits of indirect immunofluorescence, the tumor-associated Ig is bound exclusively to host-derived Fc gamma R-positive cells. Depletion of Fc gamma R-positive cells from tumor cell suspensions removed all Ig-bearing cells. Specific competitive elution of the endogenous Ig with heterologous nonimmune IgG established that the endogenous Ig was bound through the Fc gamma R. Tumor-associated Fc gamma R-positive, Ig-bearing cells could be detected with soluble antigen-antibody complexes, and mononuclear phagocytes to which the exogenous complexes were bound expressed Fc gamma R at a level significantly above normal. The role of this macrophage-associated Ig in determining the level of interaction between host cells and the tumor remains to be determined.
D000818:Animals; D000936:Antigen-Antibody Complex / Q000276:immunology; D005455:Fluorescent Antibody Technique; D005936:Glucans / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology*; D008297:Male; D008748:Methylcholanthrene; D051379:Mice; D008809:Mice, Inbred C3H; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000276:immunology; D011961:Receptors, Fc / Q000276:immunology*; D012397:Rosette Formation; D012509:Sarcoma / Q000139:chemically induced / Q000276:immunology*
D000936:Antigen-Antibody Complex; D005936:Glucans; D011961:Receptors, Fc; D008748:Methylcholanthrene