DEVELOPMENT AND CHARACTERIZATION OF MACROPHAGE HYBRIDOMAS DERIVED FROM MURINE PERITONEAL-EXUDATE CELLS

Mouse macrophage (M phi) hybridoma clones were generated by somatic cell hybridization of myeloma X63 cells (H-2(d)) with C57BL/6 (H-2(b)) peritoneal exudate cells elicited with a streptococcal preparation, OK432, or thioglycollate medium. Although they hardly adhered to plastic dishes and could not be morphologically distinguished from parental X63 tumor cells, the clones retained M phi characteristics. These included phagocytosis and production of iysozyme and nonspecific esterase, suggesting that they were hybridomas derived from M phi. Some of them expressed various levels of Ia antigen and Fc receptor. Because they induced proliferation of T cells from Balb/c mice but not those from C57BL/6 mice, the Ia antigen of M phi hybridoma was assumed to be derived from peritoneal M phi. The level of proliferation induction was correlated to the level of Ia antigen expression, Several clones produced a factor that cytostatically inhibited growth of murine mammary carcinoma and was serologically identified with arginine deiminase.