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Overcoming T cell exhaustion in infection and cancer
Kristen E Pauken1, E John Wherry1
1Institute for Immunology and Department of Microbiology, University of Pennsylvania Perelman School of Medicine, 421 Curie Blvd, Philadelphia, PA 19104, USA.
Abstract:
Inhibitors of the Programmed Cell Death 1: Programmed Cell Death 1 ligand 1 (PD-1:PD-L1) pathway, a central regulator of T cell exhaustion, have been recently shown to be effective for treatment of different cancers. However, clinical responses are mixed, highlighting the need to better understand the mechanisms of action of PD-1:PD-L1, the role of this pathway in immunity to different tumors, and the molecular and cellular effects of PD-1 blockade. Here, we review the molecular regulation of T cell exhaustion, placing recent findings on PD-1 blockade therapies in cancer in the context of the broader understanding of the roles of the PD-1:PD-L1 pathway in T cell exhaustion during chronic infection. We discuss the current understanding of the mechanisms involved in reversing T cell exhaustion, and outline critical areas of focus for future research, both basic and clinical.
Insights
Programmed Cell Death 1 (PD-1) and PD-1 ligand 1 (PD-L1) pathway inhibitors show promise in cancer treatment by reversing T cell exhaustion. Further research is needed to optimize their effectiveness and understand their mechanisms.
Area of Science:
- Immunology
- Oncology
- Molecular Biology
Background:
- The PD-1:PD-L1 pathway is crucial in regulating T cell exhaustion.
- PD-1:PD-L1 pathway inhibitors are emerging cancer therapeutics.
- Clinical responses to these inhibitors are variable.
Purpose of the Study:
- To review the molecular regulation of T cell exhaustion.
- To contextualize PD-1 blockade in cancer within T cell exhaustion during chronic infection.
- To identify future research directions for PD-1 blockade therapies.
Main Methods:
- Literature review of PD-1:PD-L1 pathway in cancer and chronic infection.
- Analysis of molecular mechanisms regulating T cell exhaustion.
- Synthesis of current understanding of PD-1 blockade effects.
Main Results:
- PD-1:PD-L1 pathway is a key target for modulating T cell exhaustion.
- Understanding this pathway's role in immunity is critical for cancer treatment.
- Mechanisms for reversing T cell exhaustion are being elucidated.
Conclusions:
- Optimizing PD-1 blockade requires a deeper understanding of its molecular and cellular effects.
- Future research should bridge basic science and clinical applications.
- Targeting T cell exhaustion is vital for improving cancer immunotherapy outcomes.
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