Females are more prone to autoimmune diseases (nearly 80% of autoimmunity patients in the U.S. are women), but the prevalence and intensity of viral, bacterial, and parasitic infections are typically reduced in females compared with males. These sex differences in susceptibility to autoimmune and infectious diseases suggest an immunological dimorphism.

A recent study by Siracusa et al., demonstrates that estradiol may strengthen innate immunity by enhancing IFN-gamma production by CD11c(+) cells. Heightened production of IFN-gamma by CD11c(+) cells in response to E2 stimulation may facilitate innate and adaptive immune responses. Previous studies illustrate that CD11c(+)NK1.1(+) cells are a significant source of innate IFN-gamma.

This observation may provide a key mechanism regulating differences in the prevalence of autoimmune diseases and susceptibility to infection between sexes.

SOURCE: J Immunol 2008, 180:1423

Read more