title: Inhibitory effect on tumour colony formation of mouse serum associated with tumour resistance in vivo in semi syngeneic mice.
abstract: Differences in tumour susceptibility between strains of mice (C57Bl/6 and C57Bl/6 X DBA/2 = B6D2F1) could be demonstrated for several tumours of C57Bl origin, both solid tumours (B16 melanoma and Lewis lung carcinoma) and lymphomas (RBL-5, 136-3 and ALC). Serum from mice with high tumour resistance in vivo (B6D2F1) showed an inhibitory effect on tumour colony formation in a soft agar colony assay. Serum from mice with lower tumour resistance (C57Bl/6) had no effect. When other F1 hybrids of C57Bl/6 parental origin were tested, the same correlation between in vitro inhibition of tumour colony formation and in vivo susceptibility was found. The serum factor was species non-specific, since the activity was expressed against in vitro grown cell lines of human origin. The tumour colony inhibitory activity was heat sensitive (56 degrees C for 30 minutes), precipitable by (NH4)2SO4, and not removed by adsorption on tumour cells. These results demonstrate the existance of a naturally-occurring humoral tumerostatic factor(s) which correlates to in vivo susceptibility to tumour cells. Its relationship to NK cell activity is discussed.
mesh_terms: D000818:Animals; D001790:Blood Physiological Phenomena; D002460:Cell Line; D002999:Clone Cells / Q000473:pathology; D006131:Growth Inhibitors / Q000097:blood*; D006824:Hybridization, Genetic; D007113:Immunity, Innate; D008175:Lung Neoplasms / Q000276:immunology; D008223:Lymphoma / Q000276:immunology; D008545:Melanoma / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D009374:Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology; D013045:Species Specificity
chemical_list: D006131:Growth Inhibitors