Host Microbe Biology

Summary – The Impact of Gut Microbiota on Gender-Specific Differences in Immunity.

Gut microbiota are different in male and female mammals, but no one has determined whether these differences are produced by innate variations in the male and female immune systems or whether immune system variations were produced by the microbiota in the gut.  To find out, Fransen et al examined the immune systems of male and female germ-free (GF) mice and discovered that innate differences in immunity already existed, including higher levels of type 1 interferon signaling in GF females and much higher levels of the gut microbes Alistipes, Rikenella, and Porphyromonadaceae, that proliferate in the absence of innate immune defense mechanisms, in GF males.  The team then transferred gut microbiota from conventional male and female mice into GF mice of the same gender or the opposite gender.  The female GF mice developed gut inflammations that produced weight loss and DNA damage if they received microbiota from conventional males. The authors concluded that microbiota-independent differences in the immune systems of males and females exist and drive gut microbiome differences between the genders.  They warned that these differences should be considered when designing treatment strategies to normalize gut microbiota caused by disease.

Original ArticleFrontiers in Immunity 2017, Volume 8, Article 754.