# Transcriptional and metabolic heterogeneity in T cell differentiation

> **NIH NIH R01** · ST. JUDE CHILDREN'S RESEARCH HOSPITAL · 2024 · $546,000

## Abstract

Program Summary/Abstract
Immunotherapies including adoptive cell therapy (ACT) and immune checkpoint blockade (ICB) represent
powerful approaches in combating cancer. CD8+ cytotoxic T lymphocytes (CTLs) are a cornerstone of cancer
immunity and exhibit inherent heterogeneity, with precursor exhausted T (Tpex) but not exhausted T (Tex) cells
responding to immunotherapies. However, poor functional and proliferative capacity of CTLs in the tumor
microenvironment limit immunotherapeutic efficacy. Further, whether and how Tex cells, which retain limited
cytolytic activity against tumors, can be reprogrammed to reinvigorate anti-tumor immunity remains largely
unknown. Thus, there is an urgent need to systemically interrogate the regulatory circuitry underlying CTL
differentiation to unleash the full immunotherapeutic potentials. Through single-cell CRISPR (scCRISPR)
screens of CD8+ T cells in vivo, we discovered two transcriptional axes, Rbpj–Irf1 and Ets1–Batf, that impinge
upon CTL differentiation states and metabolic activities. Targeting Rbpj inhibits transitory Tex (Tex1) to terminal
Tex (Tex2) cell differentiation, while targeting Ets1 promotes Tpex to transitory Tex (Tex1) cell differentiation.
Accordingly, targeting Rbpj or Ets1 enriches Tex1 cells, associated with enhanced metabolic activities, and
shows strong therapeutic efficacy in multiple murine tumor models. Low RBPJ or ETS1 expression strongly
correlates with the immunotherapeutic response in human patients with cancer, further supporting the
therapeutic relevance. Our central hypothesis is that CTL differentiation is marked by transcriptional and
metabolic heterogeneity, the targeting of which enriches Tex1 cells and promotes antitumor immunity.
Our model represents a major advance towards understanding fundamental mechanisms of T cell fate and
immunometabolism and points to new avenues to improve efficacy of cancer immunotherapies. Aim 1. Target
mediators of Tex1 to Tex2 terminal differentiation to reinvigorate exhausted T cells. Aim 2. Establish mechanisms
that control T cell metabolism and Tex1 cell generation. Aim 3. Identify combinatorial factors and metabolic
dependence for CTL differentiation. We predict our studies will establish new paradigms in T cell biology and
immuno-oncology, with the discovery of novel checkpoints and actionable targets to reprogram CTL cell fate by
enriching the Tex1 state and rewiring cellular metabolism, thereby opening new avenues to improve cancer
therapies.

## Key facts

- **NIH application ID:** 10990951
- **Project number:** 2R01AI140761-06
- **Recipient organization:** ST. JUDE CHILDREN'S RESEARCH HOSPITAL
- **Principal Investigator:** Hongbo Chi
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $546,000
- **Award type:** 2
- **Project period:** 2018-07-01 → 2029-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10990951

## Citation

> US National Institutes of Health, RePORTER application 10990951, Transcriptional and metabolic heterogeneity in T cell differentiation (2R01AI140761-06). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10990951. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*