Plasmacytoid and CD141+ Myeloid Dendritic Cells Cooperation with CD8+ T Cells in Lymph Nodes is Associated with HIV Control.

Dendritic cells (DC) are known to modulate antiviral immune responses; however, the knowledge about the role of different DC subsets in antiviral T cell priming in human tissues remains uncompleted. In the context of HIV infection, we determined the phenotype and location of plasmacytoid and CD141+ myeloid DCs (pDCs and mDCs) in lymph nodes of people living with HIV (PLWH). We found an interaction between pDCs and CD141+ mDCs with CD8+ T cells, being associated with participants' viral levels in blood and tissue. Moreover, we demonstrated a higher and more polyfunctional superantigen- and HIV-specific CD8+ T cell response after the coculture with Toll-like receptor (TLR)-primed pDCs and CD141+ mDCs. Last, we showed the potential of programmed cell death-1 (PD-1) blocking using pembrolizumab to further increase antigen-specific CD8+ T cell response along with TLR agonists. Therefore, these results showed a cooperation between pDCs, CD141+ mDCs and CD8+ T cells in lymph nodes of PLWH, which is associated with higher HIV control, highlighting the importance of DC subsets crosstalk to achieve a more potent anti-HIV response and support the use of DC-based immunotherapies for HIV control.