TY - JOUR
T1 - Inhibition of macrophage tumoricidal activity by immune complexes and altered erythrocytes
AU - Esparza, I.
AU - Green, Ralph
AU - Schreiber, R. D.
PY - 1983
Y1 - 1983
N2 - Engagement of the macrophage membrane by biologic particles including insoluble immune complexes inhibited the development of lymphokine-mediated nonspecific tumoricidal activity by murine macrophages. The degree of inhibition was dependent on the dose of particles and the lymphokine concentration. Inhibition was not due to macrophage cell death or to diminution of cell adherence after ingestion of the immune complexes. Soluble immune complexes were not inhibitory, although approximately 10% of the complexes became cell-associated. Monomeric or heat-aggregated IgG was also not inhibitory. IgG-opsonized erythrocytes (EA) were inhibitory and inhibition was dependent on the degree of opsonization. In contrast, nonopsonized erythrocytes (E), which did not bind to macrophages, were not inhibitory. Phagocytosis of glutaraldehyde-treated E or E carrying IgM antibody and complement (EAC) also led to a reduction of tumorilytic activity. Insoluble immune complexes were inhibitory when added either before or after lymphokine. Phagocytosis was neither sufficient nor necessary to cause inhibition because 1) ingestion of polystyrene latex beads did not diminish tumoricidal activity, and 2) macrophages plated on IgG-coated surfaces were inhibited with respect to the tumoricidal function. Inhibition was not affected when indomethacin (10-6 M) was included in the assay, which indicated that prostaglandins were not involved in the process. Thus, macrophage tumoricidal reponsiveness may be compromised by interaction of biologic substances with macrophage plasma membranes. This process may thereby inactivate an important host defense mechanism against neoplastic cells.
AB - Engagement of the macrophage membrane by biologic particles including insoluble immune complexes inhibited the development of lymphokine-mediated nonspecific tumoricidal activity by murine macrophages. The degree of inhibition was dependent on the dose of particles and the lymphokine concentration. Inhibition was not due to macrophage cell death or to diminution of cell adherence after ingestion of the immune complexes. Soluble immune complexes were not inhibitory, although approximately 10% of the complexes became cell-associated. Monomeric or heat-aggregated IgG was also not inhibitory. IgG-opsonized erythrocytes (EA) were inhibitory and inhibition was dependent on the degree of opsonization. In contrast, nonopsonized erythrocytes (E), which did not bind to macrophages, were not inhibitory. Phagocytosis of glutaraldehyde-treated E or E carrying IgM antibody and complement (EAC) also led to a reduction of tumorilytic activity. Insoluble immune complexes were inhibitory when added either before or after lymphokine. Phagocytosis was neither sufficient nor necessary to cause inhibition because 1) ingestion of polystyrene latex beads did not diminish tumoricidal activity, and 2) macrophages plated on IgG-coated surfaces were inhibited with respect to the tumoricidal function. Inhibition was not affected when indomethacin (10-6 M) was included in the assay, which indicated that prostaglandins were not involved in the process. Thus, macrophage tumoricidal reponsiveness may be compromised by interaction of biologic substances with macrophage plasma membranes. This process may thereby inactivate an important host defense mechanism against neoplastic cells.
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M3 - Article
C2 - 6415160
AN - SCOPUS:0020520274
VL - 131
SP - 2117
EP - 2121
JO - Journal of Immunology
JF - Journal of Immunology
SN - 0022-1767
IS - 5
ER -