Clinically effective antigen-based immunotherapy must silence antigen-experienced effector T cells (Teff) driving ongoing immune pathology. Using CD4(+) autoimmune Teff cells, we demonstrate that peptide immunotherapy (PIT) is strictly dependent upon sustained T cell expression of the co-inhibitory molecule PD-1. We found high levels of 5-hydroxymethylcytosine (5hmC) at the PD-1 (Pdcd1) promoter of non-tolerant T cells. 5hmC was lost in response to PIT, with DNA hypomethylation of the promoter. We identified dynamic changes in expression of the genes encoding the Ten-Eleven-Translocation (TET) proteins that are associated with the oxidative conversion 5-methylcytosine and 5hmC, during cytosine demethylation. We describe a model whereby promoter demethylation requires the co-incident expression of permissive histone modifications at the Pdcd1 promoter together with TET availability. This combination was only seen in tolerant Teff cells following PIT, but not in Teff that transiently express PD-1. Epigenetic changes at the Pdcd1 locus therefore determine the tolerizing potential of TCR-ligation.
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http://dx.doi.org/10.7554/eLife.03416 | DOI Listing |
Mol Cancer
December 2024
Department of Thoracic Surgery, Daping Hospital, Army Medical University, Chongqing, 400042, China.
Programmed cell death protein ligand-1 (PD-L1) and major histocompatibility complex I (MHC-I) are key molecules related to tumor immune evasion and resistance to programmed cell death protein 1 (PD-1)/PD-L1 blockade. Here, we demonstrated that the upregulation of all miRNAs in the miR-23a/27a/24 - 2 cluster was correlated with poor survival, immune evasion and PD-1/PD-L1 blockade resistance in patients with non-small cell lung cancer (NSCLC). The overexpression of all miRNAs in the miR-23a/27a/24 - 2 cluster upregulated PD-L1 expression by targeting Cbl proto-oncogene B (CBLB) and downregulated MHC-I expression by increasing the level of eukaryotic initiation factor 3B (eIF3B) via the targeting of microphthalmia-associated transcription factor (MITF).
View Article and Find Full Text PDFCell Commun Signal
December 2024
International Centre for Cancer Vaccine Science, University of Gdansk, Gdansk, Poland.
The PD-1/PDL-1 immune checkpoint inhibitors revolutionized cancer treatment, yet osteosarcoma remains a therapeutic challenge. In some types of cancer, PD-1 receptor is not solely expressed by immune cells but also by cancer cells, acting either as a tumor suppressor or promoter. While well-characterized in immune cells, little is known about the role and interactome of the PD-1 pathway in cancer.
View Article and Find Full Text PDFEMBO J
November 2024
Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon, 34134, Republic of Korea.
Nat Commun
October 2024
Department of Oral and Maxillofacial Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
Cancer Cell
October 2024
Department of Oncology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Digestive Disease and The Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Hong Kong, China; Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. Electronic address:
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