Candida yeasts normally live on human skin and mucous membranes without causing disease. In individuals with a weakened immune system, however, they are a major cause of opportunistic infections. A study published in PLOS Pathogens shows how HIV soon after infection specifically targets and destroys the very immune cells that keep Candida in check.
Opportunistic infections – clinically relevant diseases caused by usually harmless microbes – are a hallmark of HIV/AIDS and thought to be caused by a progressively weakening immune system that loses the ability to suppress even known pathogens. It is known that CD4 helper T cells, the primary target of HIV, are a key part of the immune response to many opportunistic microbes. However, HIV-positive individuals do not suddenly become susceptible to all sorts of infections. Instead, there is a consistent sequence in the vulnerability to different opportunistic pathogens during the progression of HIV-infected individuals to AIDS.
Dysfunction and preferential depletion of Candida-specific helper T cells by HIV
Image Credit: Liu FL, et al., (2016)