Predominant type 1 CMV-specific memory T-helper response in humans: evidence for gender differences in cytokine secretion

Cell-mediated memory immune responses to viral antigens are important for protection against viruses causing persistent or acute infections. This study compared the cytokine profile of memory T-helper cells specific for cytomegalovirus (CMV) in healthy CMV-seropositive men and women. The cytokine response reflected T(H)1 bias, with dominant secretion of interferon (IFN)-gamma along with moderate levels of tumor necrosis factor-alpha, interleukin (IL)-10, and IL-2. Analyzed by gender, women had higher and significant spontaneous release of IFN-gamma and CMV-specific IL-2 secretion. Similar analysis with herpes simplex virus-1 showed a trend toward higher cytokine responsiveness in women, but the differences were not statistically significant. In contrast, men had statistically significant higher influenza virus-specific tumor necrosis factor-alpha secretion. IL-4 and IL-5, both T(H)2 cytokines, were low for all three viruses. The results show a predominant T(H)1 antiviral cytokine T-help memory response with significant differences linked to gender. Such differences may have an impact in the design of immunization strategies against CMV.