Degradation of cell-bound antibodies by tumor cells from C57BL/6 mice.
A kinetic study of the disappearance of sensitizing antibody from metabolizing EL 4 cells in C57BL/6 mice revealed that this disappearance was at least partly due to the degradation of the antibody into dialyzable products. The degradation took place at 37 degrees C, but not at 4 degrees C, and occurred on or inside the cell. The process was specific inasmuch as only those IgG molecules that could bind to the cells were degraded, whereas unrelated third-party antibodies present in the culture medium remained intact. Although nonmalignant cells also have the capacity to degrade cell-bound antibodies, possibly the degradation of proteinaceous structures on antitumor effector mechanisms is, in part, responsible for decreased antitumor immunity.
D000818:Animals; D000912:Antibodies, Neoplasm; D004705:Endocytosis; D007074:Immunoglobulin G; D066298:In Vitro Techniques; D007700:Kinetics; D008228:Lymphoma, Non-Hodgkin / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D010447:Peptide Hydrolases / Q000378:metabolism; D011947:Receptors, Antigen, B-Cell; D012513:Sarcoma, Experimental / Q000201:enzymology / Q000276:immunology*; D013696:Temperature; D013997:Time Factors
D000912:Antibodies, Neoplasm; D007074:Immunoglobulin G; D011947:Receptors, Antigen, B-Cell; D010447:Peptide Hydrolases