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4DN Regulation of T cell Exhaustion

Ansu Satpathy, M.D., Ph.D.

Assistant Professor, Department of Pathology

Parker Institute for Cancer Immunotherapy

Gladstone Institute of Genomic Immunology

Stanford University School of Medicine

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Genome technologies to study cancer immunotherapy

Primary immune cells

Single-cell epigenomics

Genome engineering of immune cell therapies

Paired single-cell phenotype and TCR

Single-cell immune/tumor profiling

3D genome architecture

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Immunotherapy: Breakthrough in Cancer Treatment

Nobel Prize 2018: James Allison and Tasuku Honjo

  • What are the fundamental mechanisms of cancer immunity and immunotherapy?
  • How can we engineer novel immunotherapies to improve responses in patients?

Non-responders: ~60-70%

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Checkpoint blockade in basal cell carcinoma (BCC)

Chang ALS et al, JAAD, 2019

  • Most common cancer, ~2 million new cases/year
  • High UV-induced TMB (~65 mutations/Mb)
  • ~50% response rate to PD-1 immunotherapy

Pre-treatment

Post-treatment

Tumor

T cell

Antibody blockade

of inhibitory receptors

  • What is the diversity of T cell phenotypes in the TME?
  • What T cell types respond to PD-1 blockade?
  • What is the clonal origin of these T cells?

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Tracking the T cell response with paired single-cell RNA/TCR-seq in BCC

~28,000 TCRs (~85%)

~33,000 single cells

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Clonal expansion of CD8+ Tex cells after PD-1 blockade

CD8+ tumor-infiltrating T cells

x

Clonal expansion

Tumor specificity

T cell exhaustion

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Single-cell RNA/TCR-seq

Post-therapy TILs have a distinct TCR repertoire compared to pre-therapy TILs

x

Yost et al, Nature Medicine, 2019

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What are the molecular programs that underlie T cell exhaustion?

Wherry et al, Nat Immunology, 2011

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High-throughput single-cell epigenomics in droplets

Jeff Granja, Grace Zheng, 10x Genomics team

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Exhausted T cells exhibit a distinct epigenetic state

~5,000 unique sites

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The TEx epigenetic state does not change after PD-1 blockade

CD8+ TEx

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Summary 1: T cell exhaustion is a barrier to T cell immunotherapy

    • PD-1 blockade does not re-invigorate exhausted T cells in the tumor, but instead expands novel T cell clones.
    • Exhausted CD8+ T cells have a distinct epigenetic state, which mediates dysfunction.
    • The Tex epigenetic state is not reversed by checkpoint blockade and is a significant barrier to long-lasting immunotherapy.

Nature Medicine, 2019

Nature Biotechnology, 2019

Science, 2021

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Chimeric antigen receptor (CAR) and TCR T cell therapies for cancer

Majzner and Mackall, Nature Medicine, 2019

Monoclonal antibody

T cell receptor

Chimeric antigen receptor

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CAR-T cells also become exhausted

Lynn et al, Nature, 2019

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H3K27ac HiChIP: 3D enhancer-promoter contacts

Mumbach et al, Nat Genetics, 2017

HiChIP generates high-resolution 3D maps in primary T cells

25 Million Cells

1 Million Cells

50 Thousand Cells

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HiChIP reveals regulatory mechanisms of T cell differentiation

~50% new enhancers

~50% new contacts

2,123 differential contacts

FOXP3

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Altered chromosome conformation in exhausted CAR-T cells

Gennert et al, PNAS, 2021

Sandor et al, Unpublished

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Genome-wide CRISPR screens for T cell exhaustion and persistence

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2

Julia Belk, Winnie Yao, Nghi Ly, Unpublished

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In vitro exhaustion recapitulates the in vivo epigenetic exhaustion footprint

92% of Tex epigenetic footprint induced by chronic TCR

With Santosh Vardhana

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Epigenetic factors limit T cell persistence in vitro and in vivo

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Epigenetic factors limit T cell persistence in vitro and in vivo

In vitro

In vivo

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Epigenetic factor KO T cells preferentially maintain a progenitorTEx state

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Epigenetically-reprogrammed T cells improve anti-tumor immunity

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First-in-human CRISPR trial in engineered T cells

Stadtmauer*, Fraietta* et al, Science, 2020

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Summary 2: Regulation of T cell exhaustion for cancer immunotherapies

  • Genome-wide and multi-omic CRISPR screens identify epigenetic factors as novel targets for improved T cell persistence.

  • Epigenetic perturbation increases frequency of progenitor exhausted cells and improves the anti-tumor T cell response.

  • Can we engineer specific E-P interactions to improve T cell exhaustion?

Stadtmauer*, Fraietta* et al, Science, 2020

Belk et al, In Review, 2022

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Acknowledgments

Howard Chang (Stanford)

Katie Yost

Kevin Parker

Max Mumbach

Crystal Mackall (Stanford)

Rachel Lynn

Evan Weber

Elena Sotillo

Katie Freitas

Carl June (UPenn)

Edward Stadtmauer

Joseph Fraietta

Avery Posey

Denis Migliorini

Robbie Majzner (Stanford)

Satpathy Lab

Quanming Shi

Frank Buquicchio

Julia Belk

Joy Pai

Bence Daniel

Stefanie Meier

Nghi Ly

Max Miao

Katalin Sandor

Winnie Yao

Caleb Lareau

Aditi Limaye

Kamir Hiam-Galvez

Markus Diehl

Andy Chen

Siva Kasinathan

Christie Chang

Vincent Liu

Chris McGinnis

Emma Yin

Theo Roth

Robert Stickels

Colin Raposo

Patrick Yan

Mollie Black

Takeshi Egawa (WashU)

Saran Raju

Yu Xia

Renee Wu

Sunnie Hsiung

Matt Hellman (MSKCC)

Andrew Chow

Anne Chang (Stanford)

Will Greenleaf (Stanford)

Jeff Granja

John Wherry (UPenn)

Josephine Giles

10x Genomics

Grace Zheng

Francesca Meschi

Geoffrey McDermott