Targeting NKG2A/c+ CD8 t cells for anti-HIV-1 car-t therapy

The National Institute of Allergy and Infectious Diseases awarded The Administrators Of Tulane Educational Fund (Tulane University) $244,988 on September 1, 2026, under the Allergy and Infectious Diseases Research program (CFDA 93.855) to support research targeting NKG2A/C+ CD8 T cells for anti-HIV-1 CAR-T therapy.

The research characterizes NKG2A/C+ CD8 T cells in lymphoid tissues and evaluates whether sourcing these cells for chimeric antigen receptor T-cell therapy offers superior antiviral efficacy compared to conventional CD8 T cell-derived CAR-T cells. Aim 1 employs multiplex imaging and chip cytometry of lymph nodes to determine the precise localization of NKG2A/C+ CD8 T cells in antiretroviral-suppressed tissue. Aim 2 tranduces HIV envelope-binding CAR vectors into NKG2A/C+ CD8 T cells to assess functional superiority. Preliminary studies in rhesus macaques showed that NKG2A/C+ CD8 T cells comprised nearly half of natural killer receptor-expressing lymphocytes in lymph nodes, exhibited higher interferon-gamma secretion, lacked canonical exhaustion markers including PD-1, and displayed a stem-like IL-7R-expressing phenotype; in SIV-positive suppressed animals, their frequencies correlated inversely with lymph node SIV DNA levels.

The award supports work performed at Tulane University in Covington, Louisiana, with a period of performance from September 1, 2026, through August 31, 2028. This is a Project Grant, the standard assistance type under the NIAID research program.

Abstract

/summary a distinguishing feature of reservoir cells in long-term art suppressed persons with HIV-1 is that they exhibit evidence of selection pressure by innate immune lymphocytes. NKG2A+ NK cells and CD8+ t cells that express NKG2A (deemed innate-like CD8 t cells) are relatively well characterized in blood, where they are cytotoxic and are highly differentiated. Their residence in lymphoid tissues however is less well characterized despite the fact that these anatomic sites are highly enriched for HIV-1 DNA. In healthy uninfected rhesus macaques (RMS), we characterized NKR-expressing lymphocytes in lymph nodes (LNS) and found that in many animals, NKG2A/c+ CD8 t cells comprised nearly half of all NKR-expressing lymphocytes in the LN. These cells exhibited a unique ensemble of qualities that differentiated them from conventional memory CD8 t cells, including (1) a higher capacity to secrete interferon-gamma (2) a lack of canonical exhaustion markers including PD-1 and (3) a stem IL-7R experssing phenotype. Importantly, stem NK2A/c+ CD8 t cells persisted in the LN of SIV+ art suppressed animals and their frequencies correlated inversely to LN SIV DNA. In these preliminary studies, we were still not able to determine the precise localization of NKG2A/c+ CD8 t cells in the LN. Moreover, IT is currently not known whether licensing NKG2A/c+ CD8 t cells to recognize HIV-infected cells could offer superior antiviral efficacy in HIV remission strategies. The main objectives of this proposal are (i) to define the lymphoid localization of NKG2A/c+ CD8 t cells in the art suppressed LN and (II) whether sourcing NKG2A/c+ CD8 t cells for anti-HIV car-t therapy would be superior to car-t cells sourced from conventional CD8 t cells. Aim 1 will employ multiplex imaging of the LN with chip cytometry to determine the LN localization of NKG2A/c+ CD8 t cells. Aim 2 will transduce HIV ENV-binding car vectors under a variety of EX vivo conditions that promote t cell stemness, and in the most optimal condition, generate car-t cells from NKG2A/c+ or conventional CD8 t cells and compare their in vitro ability to kill HIV infected cells head-to- head. Finally, aim 3 will infuse large numbers of NKG2A/c+ car-t cells into a healthy animal and track their persistence and tissue distribution prior to shiv infection, expansion capacity and antiviral capacity during acute shiv infection. Based on our preliminary data, we hypothesize that NKG2A/c+ car t cells would mediate superior antiviral activity when compared to convention CD8 t cells. These studies to our knowledge will be the first to selectively target NKG2A/c+ CD8 t cells as effectors for HIV remission studies.