HBD1 was constitutively expressed in PBMCs obtained from HIV-1 uninfected subjects with levels significantly increased during acute HIV-1 infection (4-fold increase relative to HIV-1 uninfected, p = 0.0002) but not in those with chronic progressive (PG) or immunologically controlled (CT) infection (Fig 1A). Here, DEFB1 is linked to HIV-1 infection.