Profound reduction of HIV-1 reservoir cells over three decades of antiretroviral therapy started in early infancy.

HIV-1 reservoir cells persist indefinitely during suppressive antiretroviral therapy (ART) in individuals who acquire infection in adulthood, but little is known about the longitudinal evolution of viral reservoir cells during long-term ART started during early infancy. We studied two fraternal twins who acquired HIV-1 perinatally, started ART at week 10 after birth and remained on ART for 28 years. We observed that the frequency of genome intact proviruses, determined by single-genome near full-length proviral sequencing, declined by approximately 4,000- to 13,000-fold during this period, indicating enhanced decay rates of intact proviruses even after adjusting for dilution effects from somatic growth. Despite analyzing more than one billion PBMC after 28 years of ART in each participant, no intact proviruses were detected in one participant, and one intact provirus was isolated in the other. The longitudinal decline of defective proviruses in the two participants was more similar to proviral decay kinetics reported in individuals who started ART during adulthood; moreover, clonal sequence clusters were readily detectable for defective proviruses but not for intact proviruses after 28 years of ART in the two twins. Together, these data suggest decreased long-term stability and increased immunological vulnerability of intact proviruses during long-term ART started in early infancy.