HIV-1 Dynamics in Vivo: Virion Clearance Rate, Infected Cell Life-Span, and Viral Generation Time

TLDR

A new mathematical model was used to analyze detailed HIV‑1 viral load data from five patients after protease inhibitor administration. The study estimated productively infected cells live ~2.2 days, plasma virions ~0.3 days, with an average production of 1.03 × 10¹⁰ virions/day, a minimum life‑cycle duration of 1.2 days, and a generation time of 2.6 days, offering a kinetic framework for HIV‑1 pathogenesis and treatment design.

Abstract

A new mathematical model was used to analyze a detailed set of human immunodeficiency virus-type 1 (HIV-1) viral load data collected from five infected individuals after the administration of a potent inhibitor of HIV-1 protease. Productively infected cells were estimated to have, on average, a life-span of 2.2 days (half-life t 1/2 = 1.6 days), and plasma virions were estimated to have a mean life-span of 0.3 days ( t 1/2 = 0.24 days). The estimated average total HIV-1 production was 10.3 × 10 9 virions per day, which is substantially greater than previous minimum estimates. The results also suggest that the minimum duration of the HIV-1 life cycle in vivo is 1.2 days on average, and that the average HIV-1 generation time—defined as the time from release of a virion until it infects another cell and causes the release of a new generation of viral particles—is 2.6 days. These findings on viral dynamics provide not only a kinetic picture of HIV-1 pathogenesis, but also theoretical principles to guide the development of treatment strategies.