Dominant CD4+ T cell receptors remain stable throughout antiretroviral therapy-mediated immune restoration in people with HIV.

In people with HIV (PWH), the post-antiretroviral therapy (ART) window is critical for immune restoration and HIV reservoir stabilization. We employ deep immune profiling and T cell receptor (TCR) sequencing and examine proliferation to assess how ART impacts T cell homeostasis. In PWH on long-term ART, lymphocyte frequencies and phenotypes are mostly stable. By contrast, broad phenotypic changes in natural killer (NK) cells, γδ T cells, B cells, and CD4+ and CD8+ T cells are observed in the post-ART window. Whereas CD8+ T cells mostly restore, memory CD4+ T subsets and cytolytic NK cells show incomplete restoration 1.4 years post ART. Surprisingly, the hierarchies and frequencies of dominant CD4 TCR clonotypes (0.1%-11% of all CD4+ T cells) remain stable post ART, suggesting that clonal homeostasis can be independent of homeostatic processes regulating CD4+ T cell absolute number, phenotypes, and function. The slow restoration of host immunity post ART also has implications for the design of ART interruption studies.

OMIP-087: Thirty-two parameter mass cytometry panel to assess human CD4 and CD8 T cell activation, memory subsets, and helper subsets.

We developed a highly reproducible 32-marker mass cytometry panel able to measure all canonical immune lineages and perform detailed characterization of both CD4 and CD8 T cells in human peripheral blood mononuclear cells. In this panel, we identify six different T cell memory subsets, as well as markers of activation, cell cycling, and survival. In addition, this panel classifies all major CD4 T cell helper subsets. This panel enables detailed monitoring of CD4 and CD8 T cells in the context of infectious disease, cancer or autoimmunity with limited patient sample use. Detailed methods for standardization and optimization of the panel can be found in Supporting Information.