Dysbiosis of the GI Tract Microbiome in HIV Infection

Multifaceted activation of the immune system in HIV infection is thought to drive progression to AIDS and non–HIV-associated comorbidities, despite antiretroviral therapy. Although this immune activation probably has multiple causes, one culprit is clearly translocation of microbial products from the gastrointestinal (GI) tract. Previously suggested mechanisms for microbial translocation include damage to the structural barrier of the GI tract, decreased frequencies of lymphocytes that produce interleukin (IL)-17 and IL-22 within the GI tract, and abnormally elevated expression of the tryptophan-metabolizing enzyme indoleamine 2,3-deoxygenase (IDO).

In a recent study, researchers used next-generation approaches to examine tryptophan metaboli…