Sex-dependent differences in plasma cytokine responses to hantavirus infection

There are often sex differences in susceptibility to infectious diseases and in level of mortality after infection. These differences probably stem from sex-related abilities to mount proper or unwanted immune responses against an infectious agent. We report that hantavirus-infected female patients show significantly higher plasma levels of interleukin-9 (IL-9), fibroblast growth factor 2, and granulocyte-macrophage colony-stimulating factor and lower levels of IL-8 and gamma interferon-induced protein 10 than male patients. The results demonstrate that a virus infection can induce sex-dependent differences in acute immune responses in humans. This finding may, at least partly, explain the observed sex differences in susceptibility to infectious diseases and in mortality following infection.