Getting to the Guts of HIV Pathogenesis

Two groups have shown that, as in macaques infected with simian immunodeficiency virus (SIV), intestinal CD4⁺ T cells are selectively and rapidly depleted in the intestine of HIV-infected patients. Depletion of intestinal CD4⁺ T cells occurred at all stages of infection regardless of highly active antiretroviral therapy (HAART). Here we discuss the important implications of these papers for our understanding of HIV pathogenesis, treatment, and vaccine design.