HIV controllers suppress viral replication and evolution and prevent disease progression following intersubtype HIV-1 superinfection.

Objective: The aim of this study was to investigate the impact of intersubtype HIV-1 superinfection on viremia, reservoir reseeding, viral evolution and disease progression in HIV controllers (HIC).
Design: A longitudinal analysis of two Brazilian HIC individuals (EEC09 and VC32) previously identified as dually infected with subtypes B and F1 viruses.
Methods: Changes in plasma viremia, total HIV-1 DNA levels, CD4+ T-cell counts and HIV-1 quasispecies composition were measured over time. HIV-1 env diversity in peripheral blood mononuclear cell (PBMC) and plasma samples was accessed by single genome amplification and next-generation sequencing approaches, respectively. Viral evolution was evaluated by estimating nucleotide diversity and divergence.
Results: Individual EEC09 was probably initially infected with a CCR5-tropic subtype B strain and sequentially superinfected with a CXCR4-tropic subtype B strain and with a subtype F1 variant. Individual VC32 was infected with a subtype B strain and superinfected with a subtype F1 variant. The intersubtype superinfection events lead to a moderate increase in viremia and extensive turnover of viral population in plasma but exhibited divergent impact on the size and composition of cell-associated HIV DNA population. Both individuals maintained virologic control (<2000 copies/ml) and presented no evidence of viral evolution or immunologic progression for at least 2 years after the intersubtype superinfection event.
Conclusion: These data revealed that some HIC are able to repeatedly limit replication and evolution of superinfecting viral strains of a different subtype with no signs of disease progression.