HIV-1 in Lymph Nodes is Maintained by Cellular Proliferation During Antiretroviral 1 Therapy 2 3

44 To investigate the possibility that HIV-1 replication in lymph nodes sustains the reservoir 45 during antiretroviral therapy (ART), we looked for evidence of viral replication in 5 donors after up 46 to 13 years of viral suppression. We characterized proviral populations in lymph nodes and 47 peripheral blood before and during ART, evaluated the levels of viral RNA expression in single 48 lymph node and blood cells, and characterized the proviral integration sites in paired lymph node 49 and blood samples. Proviruses with identical sequences, identical integration sites, and similar 50 levels of RNA expression were found in lymph nodes and blood samples collected during ART, 51 and no single sequence with significant divergence from the pretherapy population was detected 52 in either blood or lymph nodes. These findings show that all detectable persistent HIV-1 infection 53 is consistent with maintenance in lymph nodes by clonal proliferation of cells infected before ART 54 and not by ongoing viral replication during ART. 55