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Novel assay reveals a large, inducible, replication-competent HIV-1 reservoir in resting CD4+ T cells

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Although antiretroviral therapy can suppress HIV-1 infection to undetectable levels of plasma viremia, integrated latent HIV-1 genomes that encode replication-competent virus persist in resting CD4+ T cells. This latent HIV-1 reservoir represents a major barrier to a cure. Currently, there are substantial efforts to identify therapeutic approaches that will eliminate or reduce the size of this latent HIV-1 reservoir. In this regard, a sensitive assay that can accurately and rapidly quantify inducible, replication-competent latent HIV-1 from resting CD4+ T cells is essential for HIV-1 eradication studies. Here we describe a reporter cell-based assay to quantify inducible, replication-competent latent HIV-1. This assay has several advantages over existing technology in that it (i) is sensitive; (ii) requires only a small blood volume; (iii) is faster, less labor intensive, and less expensive; and (iv) can be readily adapted into a high-throughput format. Using this assay, we show that the size of the inducible latent HIV-1 reservoir in aviremic participants on therapy is approximately 70-fold larger than previous estimates.

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Figure 1: Sensitivity of TZM-bl cells to replication-competent HIV-1.
Figure 2: TZM-bl cells are insensitive to infection by replication-defective HIV-1.
Figure 3: A TZA to quantify inducible, replication-competent HIV-1 from rCD4+ T cells.

Change history

  • 21 June 2017

    In the version of this article initially published online, the description of the fPVE calculation was incorrect. The correct description is as follows: “The fPVE was calculated by dividing IUPM values by the total HIV-1 DNA copies/million cells, as described by Cillo et al.18.” The error has been corrected in the print, PDF and HTML versions of this article.


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We thank L. Caruso and A. Anthony (University of Pittsburgh, Pittsburgh) for their technical assistance; J. Mellors (University of Pittsburgh, Pittsburgh) for plasma viral-load measurements and for discussion during the development of the assay; P. Tarwater (University of Texas, El Paso) and C. Shen (University of Pittsburgh, Pittsburgh) for statistical consultation; W. Buchanan (University of Pittsburgh, Pittsburgh) for recruitment of the Multicenter AIDS Cohort Study participants for the study; and participants of the Pittsburgh portion of the MACS for donating blood for this study. This work was supported by NIH grants U01-AI35041 (C.R.R.), R21-AI119117 (N.S.C.) and NIH Fogarty training grant fellowship D43TW010039 (P.G.).

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P.G., A.S., N.S.-C., R.B.M., B.K.P., C.R.R., N.J.V., and Y.C. designed the study, analyzed data, and wrote the manuscript. D.R., M.D., A.S., A.C., J.M.Z., and N.S.G. performed the experiments.

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Correspondence to Phalguni Gupta.

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The authors declare no competing financial interests.

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Sanyal, A., Mailliard, R., Rinaldo, C. et al. Novel assay reveals a large, inducible, replication-competent HIV-1 reservoir in resting CD4+ T cells. Nat Med 23, 885–889 (2017).

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