Sex-related differences in the pattern of coxsackievirus B-3-induced immune spleen cell cytotoxicity against virus-infected myofibers.

Spleen cells from adult BALB/c mice injected intraperitoneally with purified coxsackievirus B-3 were tested for cytotoxicity against 51Cr-labeled syngeneic infected and uninfected myofibers. Both male and female immune cells were active against uninfected targets; this reactivity was evident by day 3 of infection and persisted throughout the first week. However, we observed marked sex-related differences in immune cell cytotoxicities against infected myofibers. Males exhibited a strong T-lymphocyte response 4 to 7 days after infection. In contrast, females exhibited a weak response, and only infrequently were the immune spleen cells of females significantly more reactive against infected myofibers than against uninfected myofibers. The demonstration of a stronger effector cell response against infected myocardial cells in male mice correlates with the observation that clinical adult coxsackievirus B myocarditis and pericarditis occur predominantly in males.