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Cancer Immunology, Immunotherapy

, Volume 56, Issue 5, pp 739–745 | Cite as

Contribution of the PD-L1/PD-1 pathway to T-cell exhaustion: an update on implications for chronic infections and tumor evasion

  • Christian BlankEmail author
  • Andreas Mackensen
Symposium Paper

Abstract

Recent clinical data support ideas of Programmed death receptor-ligand 1 (PD-L1; also called B7-H1, CD274) playing an important role in immune evasion of tumor cells. Expression of PD-L1 on tumors strongly correlates with the survival of cancer patients. PD-L1 on tumors interacts with the co-inhibitory molecule Programmed death receptor-1 (PD-1, CD279) on T cells mediating decreased TCR-mediated proliferation and cytokine production. In animal tumor models, blockade of PD-L1/PD-1 interactions resulted in an improved tumor control. In addition, exhausted T cells during chronic viral infections could be revived by PD-L1 blockade. Thus, targeting PD-L1/PD-1 interactions might improve the efficacy of adoptive cell therapies (ACT) of chronic infections as well as cancers. Obstacles for a general blockade of PD-L1 might be its role in mediating peripheral tolerance. This review discusses the currently available data concerning the role of PD-L1 in tumor immune evasion and envisions possibilities for implementation into ACT for cancer patients.

Keywords

Immune Evasion Peripheral Tolerance Chronic Viral Infection Adoptive Cell Therapy Recent Clinical Data 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgment

Dr. Christian Blank is supported by the Deutsche Krebshilfe e.V. Grant No. 10-2204-Bl 1.

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Department of Hematology and OncologyUniversity of RegensburgRegensburgGermany

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