High Mobility Group Box 1 Protein Enhances HIV Replication in Newly Infected Primary T Cells

BACKGROUND: High-mobility group box 1 (HMGB1), a DNA-binding protein, has recently been shown to have effects on HIV replication, but the effects are dependent on the cell type and the timing of infection. Using human primary T cells, this study aimed to investigate the role of HMGB1 in HIV-1 replication in newly infected cells.

METHODS: Human primary T cells were infected with the HIV-1 LAI (X4) strain and then cultured in the presence of recombinant HMGB1 protein or an anti-HMGB1 antibody at various concentrations. At the indicated time points, HIV-1 p24 concentrations in the culture media were measured by ELISA. Cell proliferation, basal HMGB1 concentration, and CD3, CD4, CXCR4, and receptor for advanced glycation end products (RAGE) expression were also examined.

RESULTS: Recombinant HMGB1 could enhance HIV replication in newly infected primary T cells. In the presence of an anti-HMGB1 antibody (5 µg/mL or higher), significantly lower concentrations of HIV-1 p24 were observed in the cultures of primary T cells during the post-infection period.

CONCLUSIONS: The data presented suggest that HMGB1 plays a role in the enhancement of HIV-1 replication in newly infected T cells. This finding provides useful information toward understanding HIV pathogenesis and for the development of new therapeutic strategies.