Splenic alterations during mammary tumorigenesis: diverse effects on different immune parameters.
An evaluation of various parameters of the immune system was undertaken in Balb/c mice transplanted with a syngeneic mammary adenocarcinoma. Increasing tumor burdens resulted in a depression of some cell mediated immune functions. In contrast, an augmentation of humoral responses was observed in tumor-bearing mice. A defect in the immunoregulatory mechanism did not appear to be responsible for the elevated humoral response as revealed in suppressor cell experiments. However, flow cytometric analysis of T and B lymphocyte levels in the spleens of mice with mammary tumors indicated that the numbers of Thy 1.2 positive cells were greatly diminished while there was only a slight increase in the proportion of cells bearing surface immunoglobulin. These splenic alterations accompanying tumor growth might be responsible for the altered immune responses observed in tumor-bearing animals.
D000230:Adenocarcinoma / Q000276:immunology* / Q000473:pathology; D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology; D006968:Hypersensitivity, Delayed / Q000276:immunology; D006969:Hypersensitivity, Immediate / Q000276:immunology; D007111:Immunity, Cellular; D008213:Lymphocyte Activation; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D014185:Transplantation, Isogeneic