Biology subjects

Clayton, K. L.

Publications and source records attributed to Clayton, K. L..

3 recordsLinked to original sources

bioRxiv2026

Loss of Vpr-driven TRAIL-R2 expression protects HIV-infected cells from non-canonical NK cell TRAIL attack

HIV escapes sterilizing immunity through a variety of mechanisms, including the downregulation of MHC-I expression by HIV Nef and Vpu to counteract CD8+ T cell responses. While reduced MHC-I expression would be expected to support targeting by NK cells, a subpopulation of infected CD4+ T cells consistently resists multiple rounds of NK cell natural and antibody-dependent cytotoxicity. Studies further reveal that the HIV accessory protein Vpr induces expression of TNFRSF10B (TRAIL-R2) in CD4+ T cells, with survivors of NK cell targeting exhibiting relatively higher MHC-I and weaker expression of TRAIL-R2. In fact, reverse TRAIL signaling in NK cells leads to the release of perforin and granzymes, a pathway limited when TRAIL-R2 expression is diminished. Thus, independent of canonical death receptor signaling, TRAIL-R2 serves as an activating ligand that augments NK cell killing. These observations demonstrate that through Vpr, HIV can regulate the TRAIL/TRAIL-R2 axis to control NK cell functionality.

immunology↗

bioRxiv2025

HIV Nef amplifies mechanical heterogeneity to promote immune evasion

Intracellular pathogens must evade cytotoxic immunity to establish persistent infection. Although immune escape is typically viewed through a biochemical lens, the ability of certain pathogens to alter the mechanical properties of infected cells suggests that biophysical mechanisms may also contribute to the process. Here, we show that a subset of CD4+ T cells infected with the human immunodeficiency virus (HIV) resist elimination through a soft phenotype that inhibits killing by mechanosensitive cytotoxic T lymphocytes (CTLs). This phenotype arises from the combined effects of the HIV virulence factor Nef, which remodels the actin cytoskeleton, and intrinsic heterogeneity in the basal cytoskeletal properties of infected T cells. Pharmacological or genetic perturbations that reverse Nef signaling to the cytoskeleton or that stiffen the filamentous-actin cortex sensitize infected cells to CTL-mediated lysis. Taken together, these findings define a novel, biophysical paradigm of immune evasion with implications for HIV cure strategies.

immunology↗

bioRxiv2024

The EZH2 inhibitor tazemetostat mitigates HIV immune evasion, reduces reservoir formation, and promotes durable CD8+ T-cell revitalization

Persistent HIV reservoirs in CD4 T-cells pose a barrier to curing HIV infection. We identified overexpression of enhancer of zeste homolog 2 (EZH2) in HIV-infected CD4 T- cells that survive cytotoxic T lymphocyte (CTL) exposure, suggesting a mechanism of CTL resistance. Inhibition of EZH2 with the FDA-approved drug tazemetostat increased surface expression of major histocompatibility complex class I (MHC-I) on CD4 T-cells, counterbalancing HIV Nef-mediated MHC-I downregulation. This improved CTL-mediated elimination of HIV-infected cells and suppressed viral replication in vitro. In a participant-derived xenograft mouse model, tazemetostat elevated MHC-I and the pro-apoptotic protein BIM in CD4 T-cells, facilitating CD8 T-cell-mediated reductions of HIV reservoir seeding. Additionally, tazemetostat promoted sustained skewing of CD8 T-cells toward less differentiated and exhausted phenotypes. Our findings reveal EZH2 overexpression as a novel mechanism of CTL resistance and support the clinical evaluation of tazemetostat to enhance clearance of HIV reservoirs and improve CD8+ T-cell function.

immunology↗