Cell surface inhibitory receptors (IRs) PD1 and LAG3 control cellular signaling and critical cell intrinsic effector T cell function and differentiation. Yet, these IRs are also expressed on exhausted intratumoral T cells, limiting disease clearance. IRs are critical to maintain immune control, but also represent a major barrier to effective anti-tumor immunity. PD1 and LAG3 are synergistic in multiple diseases, including cancers, and many CD8+ and CD4+ tumor-infiltrating lymphocytes (TILs) express PD1/LAG3. Indeed, we showed that tumor immunotherapy targeting PD1/LAG3 can induce almost complete remission of tumors in mice, and clinical evidence now supports the benefit of single (anti-PD1) or dual (anti-PD1/LAG3) IR blockade. This project will test the central hypothesis that ?PD1 and LAG3 synergize to enforce tumor-induced tolerance using a combination of overlapping and unique cell intrinsic and extrinsic functions in CD4+ and CD8+ effector T cells?. Due to potency of tolerance in the tumor microenvironment (TME), mouse models represent an outstanding system to study IR mechanisms to compare with processes in autoimmune (Project 1) and chronic viral settings (Project 3). We will pursue 3 Aims:
AIM 1 : What are the relative and synergistic contributions of PD1 and LAG3 in limiting the initial CD8+ T cell anti-tumor effector response? We hypothesize that ?PD1 and LAG3 do not initiate but temporally re- enforce progression toward CD8+ T cell exhaustion by limiting population dynamics, differentiation, metabolic health, and polyfunctionality?. We will use a Quad AT system that co-transfers tumor-specific CD8+ T cells that are wild-type or lack PD1 and/or LAG3 for functional and transcriptional analysis in the same microenvironment.
AIM 2 : What are the relative and synergistic contributions of PD1 and LAG3 in limiting initial CD4+ Tconv anti-tumor effector response? We hypothesize that ?PD1/LAG3 have synergistic effects on CD4+ Tconv cells by differentially modulating their function and capacity for CD8+ T cell help?. We will interrogate the role of PD1/LAG3 on CD4+ T cells using our novel CreERT2 line to delete alleles in CD4+ Tconv but not CD8+ T cells or T regs .
AIM 3 : What is the impact of PD1/LAG3 on the durability of anti-tumor T cell memory and maintenance of systemic immunity? We hypothesize that ?PD1 and/or LAG3 limit durability of anti-tumor immunity by impacting Tex reinvigoration and Tconv cell memory development and maintenance, blunting their recall response and limiting systemic immunity?. We will ask 2 questions: (A) What is the impact of PD1/LAG3 loss on Tex and their reinvigoration? (B) What is the impact of PD1/LAG3 on maintenance of T cell anti-tumor memory and recall response? PPG Interactions: Project 2 will collaborate with Project 1 to compare the impact of PD1/LAG3 loss on CD4+ T cell function in autoimmune versus tumoral settings; with Project 3 to compare CD8+ T cell exhaustion induced by tumors or chronic viral infections; and with Core A to exchange data, Core B to obtain mice, Core C for transcriptional analysis and CRISPR/sgRNA sequences, and Core D for immunohistological analysis.

Public Health Relevance

The inhibitory receptors PD1 and LAG3 synergize to limit autoimmune disease. However, they are highly expressed on intratumoral T cells and thus limit effective anti-tumor immunity. Although PD1 and LAG3 are now major therapeutic targets, it is not clear how they mediated this synergistic regulation and on which cells types. A greater understanding of these issues could lead to move effective therapeutic strategies and biomarker discovery.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program Projects (P01)
Project #
2P01AI108545-06
Application #
10023669
Study Section
Special Emphasis Panel (ZAI1)
Project Start
2015-05-15
Project End
2025-07-31
Budget Start
2020-06-01
Budget End
2021-05-31
Support Year
6
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of Pittsburgh
Department
Type
DUNS #
004514360
City
Pittsburgh
State
PA
Country
United States
Zip Code
15260
Stelekati, Erietta; Chen, Zeyu; Manne, Sasikanth et al. (2018) Long-Term Persistence of Exhausted CD8 T Cells in Chronic Infection Is Regulated by MicroRNA-155. Cell Rep 23:2142-2156
Bengsch, Bertram; Ohtani, Takuya; Khan, Omar et al. (2018) Epigenomic-Guided Mass Cytometry Profiling Reveals Disease-Specific Features of Exhausted CD8 T Cells. Immunity 48:1029-1045.e5
Overacre-Delgoffe, Abigail E; Vignali, Dario A A (2018) Treg Fragility: A Prerequisite for Effective Antitumor Immunity? Cancer Immunol Res 6:882-887
Ratay, Michelle L; Glowacki, Andrew J; Balmert, Stephen C et al. (2017) Treg-recruiting microspheres prevent inflammation in a murine model of dry eye disease. J Control Release 258:208-217
Huang, Alexander C; Postow, Michael A; Orlowski, Robert J et al. (2017) T-cell invigoration to tumour burden ratio associated with anti-PD-1 response. Nature 545:60-65
Hope, Jennifer L; Stairiker, Christopher J; Spantidea, Panagiota I et al. (2017) The Transcription Factor T-Bet Is Regulated by MicroRNA-155 in Murine Anti-Viral CD8+ T Cells via SHIP-1. Front Immunol 8:1696
Andrews, Lawrence P; Marciscano, Ariel E; Drake, Charles G et al. (2017) LAG3 (CD223) as a cancer immunotherapy target. Immunol Rev 276:80-96
Chen, Zeyu; Stelekati, Erietta; Kurachi, Makoto et al. (2017) miR-150 Regulates Memory CD8 T Cell Differentiation via c-Myb. Cell Rep 20:2584-2597
Zhang, Qianxia; Chikina, Maria; Szymczak-Workman, Andrea L et al. (2017) LAG3 limits regulatory T cell proliferation and function in autoimmune diabetes. Sci Immunol 2:
Kurachi, Makoto; Kurachi, Junko; Chen, Zeyu et al. (2017) Optimized retroviral transduction of mouse T cells for in vivo assessment of gene function. Nat Protoc 12:1980-1998

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