RECOVERY OF REPLICATION-COMPETENT HIV DESPITE PROLONGED SUPPRESSION OF PLASMA VIREMIA

In evaluating current combination drug regimens for treatment of human immunodeficiency virus (HIV) disease, it is important to determine th e existence of viral reservoirs. After depletion of CD8 cells from the peripheral blood mononuclear cells (PBMCs) of both patients and norma l donors, activation of patient CD4 lymphocytes with immobilized antib odies to CD3 and CD28 enabled the isolation of virus from PBMCs of six patients despite the suppression of their plasma HIV RNA to fewer tha n 50 copies per milliliter for up to 2 years. Partial sequencing of HI V pol revealed no new drug resistance mutations or discernible evoluti on, providing evidence for viral latency rather than drug failure.