How Does Biological Sex Impact Mucosal Bacterial Infection? Mucosal Defenses and Bacterial Detection

Urinary tract infections possess substantial sex disparities in the incidence, immune response, and progression of infection. Some of these distinctions may be due to sexual dimorphism in mucosal barriers or sex differences in the initial immune response to infection. Mucosal organs are protected by a mucus barrier, however, there is little knowledge of the impact of biological sex on this layer in homeostasis and infection. Notably, despite the incidence of infection, there is a paucity of even fundamental research on bladder mucus in homeostasis and infectious disease. When bacteria encounter mucosal epithelia, they must bind and potentially invade these surfaces to initiate an infection. Whether differences in mucosal epithelia have an impact on bacterial-epithelial interactions between the sexes is not known. When bacteria are sensed by the host, they initiate transcription factor activation, which may differ by sex of the host. Finally, sex steroid hormone receptor signaling likely also impacts innate immunity between the sexes, leading to the divergence between the sexes observed in mucosa infection.