FIG. 9.

HIV-1 that persists in the resting CD4⁺ T cells of patients failing HAART is archival in nature. (A and B) HIV-1 from the resting CD4⁺ T cells of patients failing HAART has a lower divergence than contemporaneous plasma virus. Divergence calculated from an inferred MRCA is shown for two representative patients. Error bars depict the standard errors determined by bootstrap analysis with 100 repetitions. (C) Persistence of resistance mutations to a previously taken antiretroviral drug. (Top panel)The genotypes of independent clones from patient 138 demonstrate persistence of an M184V mutation that confers resistance to 3TC in resting CD4⁺ T cells, but not in plasma. (Bottom panel) The plasma HIV-1 RNA levels and treatment history for patient 138 show that the patient was last on a 3TC-containing regimen 65 months prior to sampling. Open symbols for the plasma HIV-1 RNA levels indicate measurements below the limit of detection (either <400 or <50 HIV-1 RNA copies/ml). The black line and arrow indicate the sampling time point. Antiretroviral drug abbreviations: AZT, zidovudine; 3TC, lamivudine; ddI, didanosine; d4T, stavudine; HU, hydroxyurea; NVP, nevirapine; SQV, saquinavir; RTV, ritonavir; TDF, tenofovir disoproxil fumarate; ABC, abacavir.