Systemic effects of methylcholanthrene in mice. II. Immune responses to sheep red cells.
Assays of splenic plaque-forming cells (PFC) for sheep red cells (SRC), done in parallel in control and methylcholanthrene (MCA)-injected mice of strains C3H/eB and C57BL/6, disclosed immunodepression, the degree of which depended on strain and sex of mice, and time elapsed between injection of MCA and performance of test. The most severe and long-lasting effects were observed in male C3H/eB mice, and the least impairment was seen in female C57BL/6 mice. After surgical splenectomy for assay of PFC, MCA-injected mice were observed for appearance of induced tumors up to 52 weeks after administration of carcinogen. In most groups of C57BL/6, but only rarely in C3H/eB mice, a correlation was found in individual mice between immunodepression and appearance of tumor. Since, however, the incidence of induced tumors was higher in C57BL/6 than in C3H/eB mice, immunodepression cannot be considered a universally obligatory step in carcinogenesis, but its involvement may be limited to particular phenotypes.
D000818:Animals; D004912:Erythrocytes / Q000276:immunology*; D005260:Female; D006462:Hemolytic Plaque Technique; D007108:Immune Tolerance / Q000187:drug effects*; D008297:Male; D008748:Methylcholanthrene / Q000633:toxicity*; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D012737:Sex Factors; D012756:Sheep; D013045:Species Specificity; D013154:Spleen / Q000187:drug effects; D013156:Splenectomy
D008748:Methylcholanthrene