49. Cohabitation with a sick cage-mate induce immune changes

Introduction: It was shown that cohabitation with a sick cage-mate induced behavioral and physiological changes. The present work was designed to analyze (1) the total cellularity of spleen’s cells in mice that cohabited with a sick cage-mate and (2) the profile phenotypic in the same cells of these animals. Methods: Mice were paired according to their weights and were divided into 2 groups: one control (C) and one experimental (E). One mouse of each control pair was injected with PBS and the other was kept undisturbed being designed “health companion (HC). One animal of each experimental pair of mice was i.p. inoculated with 5 × 106 Ehrlich tumor cells; the other animal, the object of this study was kept undisturbed being called “sick companion” (SC). Fourteen days after tumor cells or control solution injections the experiment was done. Results showed that cohabitation with a sick cage-mate produced a significant reduction in the total cellularity of the spleen and were observed in the phenotypic studies a significant reduction of T helper; as well as in the Lymphocyte B; However, no significant differences were found in T citotoxic, between both groups; but a significant reduction was observed in the proportion of CD4/CD8. Conclusion: The present data provide experimental evidence that cohabitation with a tumor bearing mice induces a decrease in levels of lymphocytes T helper and B.