Gut-homing α4β7 CD4+ T cells: potential key players in both acute HIV infection and HIV-associated cancers

During acute human immunodeficiency virus (HIV) infection, depletion of CD4+ T cells in the host gut mucosa occurs prior to its occurrence in the peripheral blood and other lymphoid tissues. Expression of integrin α4β7, a gut-homing receptor on CD4+ T cells, not only provides a potential receptor for HIV but also plays a critical role in lymphocyte migration from the circulation to the intestine.