1
|
Liu D, Hu X, Chen Z, Wei W, Wu Y. Key links in the physiological regulation of the immune system and disease induction: T cell receptor -CD3 complex. Biochem Pharmacol 2024; 227:116441. [PMID: 39029632 DOI: 10.1016/j.bcp.2024.116441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 07/12/2024] [Accepted: 07/16/2024] [Indexed: 07/21/2024]
Abstract
T cell receptor (TCR) is a kind of surface marker that are specific to T cells. The TCR regulates T cell function and participates in the body's immunological response to prevent immune dysregulation and inflammatory reactions by identifying and binding exogenous antigens. Due to its brief intracellular segment, TCR requires intracellular molecules to assist with signaling. Among these, the CD3 molecule is one of the most important. The CD3 molecule involves in TCR structural stability as well as T cell activation signaling. A TCR-CD3 complex is created when TCR and CD3 form a non-covalent bond. Antigen recognition and T cell signaling are both facilitated by the TCR-CD3 complex. When a CD3 subunit is absent, a TCR-CD3 complex cannot form, and none of the subunits is transported to the cell surface. Thus, T cells cannot develop. Consequently, research on the physiological functions and potential pathogenicity of CD3 subunits can clarify the pathogenesis of immune system diseases and can offer fresh approaches to the treatment of it. In this review, the structure and function of the TCR-CD3 complex in the immune system was summarized, the pathogenicity of each CD3 subunit and therapeutic approaches to related diseases was explored and research directions for the development of new targeted drugs was provided.
Collapse
Affiliation(s)
- Danyan Liu
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-inflammatory and Immune Medicine, Anhui Provincial Institute of Translational Medicine, Hefei 230032, China
| | - Xiaoxi Hu
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-inflammatory and Immune Medicine, Anhui Provincial Institute of Translational Medicine, Hefei 230032, China
| | - Zhaoying Chen
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-inflammatory and Immune Medicine, Anhui Provincial Institute of Translational Medicine, Hefei 230032, China
| | - Wei Wei
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-inflammatory and Immune Medicine, Anhui Provincial Institute of Translational Medicine, Hefei 230032, China.
| | - Yujing Wu
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-inflammatory and Immune Medicine, Anhui Provincial Institute of Translational Medicine, Hefei 230032, China.
| |
Collapse
|
2
|
Zhang R, Zhang J, Zhou X, Zhao A, Yu C. The establishment and application of CD3E humanized mice in immunotherapy. Exp Anim 2022; 71:442-450. [PMID: 35570001 PMCID: PMC9671771 DOI: 10.1538/expanim.22-0012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/13/2022] [Indexed: 07/22/2024] Open
Abstract
In the field of cancer immunotherapy, monoclonal antibody drugs, bispecific antibodies, and antibody-conjugated drugs have become the focus of current research, and gene-edited animal models play an essential role in the entire drug development process. In this study, CD3E humanized mice were established by replacing the second to the seventh exon of the Cd3e mouse gene with the same exon of the human gene. The expression of human CD3E in CD3E humanized mice was detected by RT-PCR as well as flow cytometry, also a tumor model was established based on CD3E humanized mice, and the pharmacodynamic effects of CD3E monoclonal antibodies were evaluated. The results showed that CD3E humanized mice expressed only human CD3E, and the proportion of each lymphocyte in the thymus and spleen was not significantly changed compared with wild-type mice. CD3E monoclonal antibody could promote tumor growth after treatment, which may be related to the activation-induced cell death effect caused by this CD3E antibody. In contrast, Bispecific antibody blinatumomab inhibited tumor growth significantly. Thus, the CD3E humanized mice provided an adequate animal model for evaluating the efficacy and safety of CD3E antibody drugs.
Collapse
Affiliation(s)
- Rufeng Zhang
- College of life science and technology, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Chaoyang District, Beijing 100029, P.R. China
| | - Jing Zhang
- Biocytogen Pharmaceuticals (Beijing) Co., Ltd., 12 Baoshen South Street, Daxing District,102609, Beijing, P.R. China
| | - Xiaofei Zhou
- Biocytogen Pharmaceuticals (Beijing) Co., Ltd., 12 Baoshen South Street, Daxing District,102609, Beijing, P.R. China
| | - Ang Zhao
- Biocytogen Pharmaceuticals (Beijing) Co., Ltd., 12 Baoshen South Street, Daxing District,102609, Beijing, P.R. China
| | - Changyuan Yu
- College of life science and technology, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Chaoyang District, Beijing 100029, P.R. China
| |
Collapse
|
3
|
Lu X, Li C, Xu W, Wu Y, Wang J, Chen S, Zhang H, Huang H, Huang H, Liu W. Malignant Tumor Purity Reveals the Driven and Prognostic Role of CD3E in Low-Grade Glioma Microenvironment. Front Oncol 2021; 11:676124. [PMID: 34557404 PMCID: PMC8454269 DOI: 10.3389/fonc.2021.676124] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 07/02/2021] [Indexed: 12/23/2022] Open
Abstract
The tumor microenvironment (TME) contributes to the initiation and progression of many neoplasms. However, the impact of low-grade glioma (LGG) purity on carcinogenesis remains to be elucidated. We selected 509 LGG patients with available genomic and clinical information from the TCGA database. The percentage of tumor infiltrating immune cells and the tumor purity of LGG were evaluated using the ESTIMATE and CIBERSORT algorithms. Stromal-related genes were screened through Cox regression, and protein-protein interaction analyses and survival-related genes were selected in 487 LGG patients from GEO database. Hub genes involved in LGG purity were then identified and functionally annotated using bioinformatics analyses. Prognostic implications were validated in 100 patients from an Asian real-world cohort. Elevated tumor purity burden, immune scores, and stromal scores were significantly associated with poor outcomes and increased grade in LGG patients from the TCGA cohort. In addition, CD3E was selected with the most significant prognostic value (Hazard Ratio=1.552, P<0.001). Differentially expressed genes screened according to CD3E expression were mainly involved in stromal related activities. Additionally, significantly increased CD3E expression was found in 100 LGG samples from the validation cohort compared with adjacent normal brain tissues. High CD3E expression could serve as an independent prognostic indicator for survival of LGG patients and promotes malignant cellular biological behaviors of LGG. In conclusion, tumor purity has a considerable impact on the clinical, genomic, and biological status of LGG. CD3E, the gene for novel membrane immune biomarker deeply affecting tumor purity, may help to evaluate the prognosis and develop individual immunotherapy strategies for LGG patients. Evaluating the ratio of differential tumor purity and CD3E expression levels may provide novel insights into the complex structure of the LGG microenvironment and targeted drug development.
Collapse
Affiliation(s)
- Xiuqin Lu
- Department of Nursing and Health Management, Shanghai University of Medicine & Health Sciences, Shanghai, China
| | - Chuanyu Li
- Department of Neurosurgery, Affiliated Hospital of Youjiang Medical University for Nationalities, Guangxi, China
| | - Wenhao Xu
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai Medical University, Fudan University, Shanghai, China
| | - Yuanyuan Wu
- Department of Gastroenterology, Naval Medical Center of People’s Liberation Army (PLA) of China, Naval Military Medical University, Shanghai, China
| | - Jian Wang
- Department of Transplantation, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shuxian Chen
- Department of Oncology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hailiang Zhang
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai Medical University, Fudan University, Shanghai, China
| | - Huadong Huang
- Department of Neurosurgery, Affiliated Hospital of Youjiang Medical University for Nationalities, Guangxi, China
| | - Haineng Huang
- Department of Neurosurgery, Affiliated Hospital of Youjiang Medical University for Nationalities, Guangxi, China
| | - Wangrui Liu
- Department of Nursing and Health Management, Shanghai University of Medicine & Health Sciences, Shanghai, China
- Department of Neurosurgery, Affiliated Hospital of Youjiang Medical University for Nationalities, Guangxi, China
| |
Collapse
|
4
|
Cui G, Geng L, Zhu L, Lin Z, Liu X, Miao Z, Jiang J, Feng X, Wei F. CFP is a prognostic biomarker and correlated with immune infiltrates in Gastric Cancer and Lung Cancer. J Cancer 2021; 12:3378-3390. [PMID: 33976747 PMCID: PMC8100816 DOI: 10.7150/jca.50832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 03/21/2021] [Indexed: 01/06/2023] Open
Abstract
Complement factor properdin (CFP), encodes plasma glycoprotein, is a critical gene that regulates the complement pathway of the innate immune system. However, correlations of CFP in cancers remain unclear. In this study, the expression pattern and prognostic value of CFP in pan-cancer were analyzed via the Oncomine, PrognoScan, GEPIA and Kaplan-Meier plotters. In addition, we used immunohistochemical staining to validate CFP expression in clinical tissue samples. Finally, we evaluated the correlations between CFP and cancer immune infiltrates particularly in stomach adenocarcinoma (STAD) and lung adenocarcinoma (LUAD) by using GEPIA and TIMER databases. The results of database analysis and immunohistochemistry showed that the expression level of CFP in STAD and LUAD was lower than that in normal tissues. Low expression level of CFP was associated with poorer overall survival (OS), first progression (FP), post progression survival (PPS) and was detrimental to the prognosis of STAD and LUAD, specifically in stage 3, stage T3, stage N2 and N3 of STAD (P<0.05). Moreover, expression of CFP had significant positive correlations with the infiltration levels of CD8+ T cells, CD4+ T cells, macrophages, neutrophils and dendritic cells (DCs) in STAD and LUAD. Furthermore, gene markers of infiltrating immune cells exhibited different CFP-related immune infiltration patterns such as tumor-associated-macrophages (TAMs). These results suggest that CFP can serve as a prognostic biomarker for determining prognosis and immune infiltration in STAD and LUAD.
Collapse
Affiliation(s)
- Guoliang Cui
- Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.,Institute of Integrated Chinese and Western Medicine, Nanjing Medical University, Nanjing 210029, Jiangsu, China.,The Second Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210017, Jiangsu, China
| | - Le Geng
- Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.,Institute of Integrated Chinese and Western Medicine, Nanjing Medical University, Nanjing 210029, Jiangsu, China
| | - Li Zhu
- The Second Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210017, Jiangsu, China
| | - Zhenyan Lin
- Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.,Institute of Integrated Chinese and Western Medicine, Nanjing Medical University, Nanjing 210029, Jiangsu, China
| | - Xuan Liu
- Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.,Institute of Integrated Chinese and Western Medicine, Nanjing Medical University, Nanjing 210029, Jiangsu, China
| | - Zhengyue Miao
- Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.,Institute of Integrated Chinese and Western Medicine, Nanjing Medical University, Nanjing 210029, Jiangsu, China
| | - Jintao Jiang
- Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.,Institute of Integrated Chinese and Western Medicine, Nanjing Medical University, Nanjing 210029, Jiangsu, China
| | - Xiaoke Feng
- Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.,Institute of Integrated Chinese and Western Medicine, Nanjing Medical University, Nanjing 210029, Jiangsu, China
| | - Fei Wei
- Department of Physiology, School of medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu, China
| |
Collapse
|
5
|
Abidi A, Laurent T, Bériou G, Bouchet-Delbos L, Fourgeux C, Louvet C, Triki-Marrakchi R, Poschmann J, Josien R, Martin J. Characterization of Rat ILCs Reveals ILC2 as the Dominant Intestinal Subset. Front Immunol 2020; 11:255. [PMID: 32140157 PMCID: PMC7043102 DOI: 10.3389/fimmu.2020.00255] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 01/30/2020] [Indexed: 12/17/2022] Open
Abstract
Innate lymphoid cells (ILCs) are tissue-resident lymphocytes that lack antigen-specific receptors and exhibit innate effector functions such as cytokine production that play an important role in immediate responses to pathogens especially at mucosal sites. Mouse and human ILC subsets have been extensively characterized in various tissues and in blood. In this study, we present the first characterization of ILCs and ILC subsets in rat gut and secondary lymphoid organs using flow cytometry and single cell RNA sequencing. Our results show that phenotype and function of rat ILC subsets are conserved as compared to human and mouse ILCs. However, and in contrast to human and mouse, our study unexpectedly revealed that ILC2 and not ILC3 was the dominant ILC subset in the rat intestinal lamina propria. ILC2 predominance in the gut was independent of rat strain, sex or housing facility. In contrast, ILC3 was the predominant ILC subset in mesenteric lymph nodes and Peyer patches. In conclusion, our study demonstrates that in spite of highly conserved phenotype and function between mice, rat and humans, the distribution of ILC subsets in the intestinal mucosa is dependent on the species likely in response to both genetic and environmental factors.
Collapse
Affiliation(s)
- Ahmed Abidi
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France.,Université de Tunis El Manar, Laboratoire de Génétique, Immunologie et Pathologies Humaines, Faculté des Sciences de Tunis, Tunis, Tunisia
| | - Thomas Laurent
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Gaëlle Bériou
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Laurence Bouchet-Delbos
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Cynthia Fourgeux
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Cédric Louvet
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Raja Triki-Marrakchi
- Université de Tunis El Manar, Laboratoire de Génétique, Immunologie et Pathologies Humaines, Faculté des Sciences de Tunis, Tunis, Tunisia
| | - Jeremie Poschmann
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Régis Josien
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France.,CHU Nantes, Laboratoire d'Immunologie, Nantes, France
| | - Jérôme Martin
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France.,CHU Nantes, Laboratoire d'Immunologie, Nantes, France
| |
Collapse
|
6
|
Hardy IR, Schamel WW, Baeuerle PA, Getts DR, Hofmeister R. Implications of T cell receptor biology on the development of new T cell therapies for cancer. Immunotherapy 2020; 12:89-103. [PMID: 31902264 DOI: 10.2217/imt-2019-0046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Recently, two chimeric antigen receptor (CAR) T cell therapies were approved based on their remarkable efficacy in patients with hematological malignancies. By contrast, CAR-T cell therapies results in solid tumors have been less promising. To develop the next generation of T cell therapies a better understanding of T cell receptor (TCR) biology and its implication for the design of synthetic receptors is critical. Here, we review current and newly developed forms of T cell therapies and how their utilization of different components of the TCR signaling machinery and their requirement for engagement (or not) of human leukocyte antigen impacts their design, efficacy and applicability as cancer drugs. Notably, we highlight the development of human leukocyte antigen-independent T cell platforms that utilize the full TCR complex as having promise to overcome some of the limitations of existing T cell therapies.
Collapse
Affiliation(s)
- Ian R Hardy
- TCR2 Therapeutics, Inc., 100 Binney St. Suite 710, Cambridge, MA 02142, USA
| | - Wolfgang W Schamel
- Department of Immunology, Faculty of Biology, BIOSS Center for Biological Signalling Studies, CIBSS - Centre for Integrative Biological Signalling Studies & Centre for Chronic Immunodeficiency CCI, University of Freiburg, Schänzlestraβe 18,79104 Freiburg, Germany
| | - Patrick A Baeuerle
- TCR Therapeutics, Inc., 100 Binney St. Suite 710, Cambridge, MA 02142, USA.,Institute for Immunology, Ludwig-Maximilians-University Munich, Grosshadernerstr. 9, 82152 Planegg-Martinsried, Germany
| | - Daniel R Getts
- TCR Therapeutics, Inc., 100 Binney St. Suite 710, Cambridge, MA 02142, USA
| | - Robert Hofmeister
- TCR Therapeutics, Inc., 100 Binney St. Suite 710, Cambridge, MA 02142, USA
| |
Collapse
|
7
|
Ngoenkam J, Schamel WW, Pongcharoen S. Selected signalling proteins recruited to the T-cell receptor-CD3 complex. Immunology 2018; 153:42-50. [PMID: 28771705 PMCID: PMC5721247 DOI: 10.1111/imm.12809] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 07/26/2017] [Accepted: 07/27/2017] [Indexed: 12/22/2022] Open
Abstract
The T-cell receptor (TCR)-CD3 complex, expressed on T cells, determines the outcome of a T-cell response. It consists of the TCR-αβ heterodimer and the non-covalently associated signalling dimers of CD3εγ, CD3εδ and CD3ζζ. TCR-αβ binds specifically to a cognate peptide antigen bound to an MHC molecule, whereas the CD3 subunits transmit the signal into the cytosol to activate signalling events. Recruitment of proteins to specialized localizations is one mechanism to regulate activation and termination of signalling. In the last 25 years a large number of signalling molecules recruited to the TCR-CD3 complex upon antigen binding to TCR-αβ have been described. Here, we review knowledge about five of those interaction partners: Lck, ZAP-70, Nck, WASP and Numb. Some of these proteins have been targeted in the development of immunomodulatory drugs aiming to treat patients with autoimmune diseases and organ transplants.
Collapse
MESH Headings
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- CD3 Complex/chemistry
- CD3 Complex/genetics
- CD3 Complex/metabolism
- Carrier Proteins/chemistry
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Humans
- Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/metabolism
- Membrane Proteins/metabolism
- Mutation
- Nerve Tissue Proteins/metabolism
- Oncogene Proteins/metabolism
- Protein Binding
- Protein Interaction Domains and Motifs
- Receptor-CD3 Complex, Antigen, T-Cell/chemistry
- Receptor-CD3 Complex, Antigen, T-Cell/metabolism
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/metabolism
- Signal Transduction
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- Wiskott-Aldrich Syndrome Protein/metabolism
- ZAP-70 Protein-Tyrosine Kinase/metabolism
Collapse
Affiliation(s)
- Jatuporn Ngoenkam
- Department of Microbiology and ParasitologyFaculty of Medical ScienceNaresuan UniversityPhitsanulokThailand
| | - Wolfgang W. Schamel
- Department of ImmunologyInstitute for Biology IIIFaculty of BiologyUniversity of FreiburgFreiburgGermany
- BIOSS Centre for Biological Signalling StudiesUniversity of FreiburgFreiburgGermany
- Centre for Chronic Immunodeficiency (CCI)Medical Centre‐University of FreiburgFaculty of MedicineUniversity of FreiburgFreiburgGermany
| | - Sutatip Pongcharoen
- Centre of Excellence in Medical BiotechnologyFaculty of Medical ScienceNaresuan UniversityPhitsanulokThailand
- Centre of Excellence in Petroleum, Petrochemicals and Advanced MaterialsFaculty of ScienceNaresuan UniversityPhitsanulokThailand
- Department of MedicineFaculty of MedicineNaresuan UniversityPhitsanulokThailand
| |
Collapse
|
8
|
Crk adaptor proteins regulate CD3ζ chain phosphorylation and TCR/CD3 down-modulation in activated T cells. Cell Signal 2017; 36:117-126. [PMID: 28465009 DOI: 10.1016/j.cellsig.2017.04.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/15/2017] [Accepted: 04/26/2017] [Indexed: 01/06/2023]
Abstract
T cell receptor (TCR) recognition of a peptide antigen in the context of MHC molecules initiates positive and negative cascades that regulate T cell activation, proliferation and differentiation, and culminate in the acquisition of effector T cell functions. These processes are a prerequisite for the induction of specific T cell-mediated adaptive immune responses. A key event in the activation of TCR-coupled signaling pathways is the phosphorylation of tyrosine residues within the cytoplasmic tails of the CD3 subunits, predominantly CD3ζ. These transiently formed phosphotyrosyl epitopes serve as docking sites for SH2-domain containing effector molecules, predominantly the ZAP70 protein tyrosine kinase, which is critical for signal propagation. We found that CrkI and CrkII adaptor proteins also interact with CD3ζ in TCR activated-, but not in resting-, T cells. Crk binding to CD3ζ was independent of ZAP70 and also occurred in ZAP70-deficient T cells. Binding was mediated by Crk-SH2 domain interaction with phosphotyrosine-containing motifs on CD3ζ, via a direct physical interaction, as demonstrated by Far-Western blot. CrkII binding to CD3ζ could also be demonstrated in a heterologous system, where coexpression of a catalytically active Lck was used to phosphorylate the CD3ζ chain. TCR activation-induced Crk binding to CD3ζ resulted in increased and prolonged phosphorylation of CD3ζ, as well as ZAP70 and LAT, suggesting a positive role for CrkI/II binding to CD3ζ in regulation of TCR-coupled signaling pathways. Furthermore, Crk-dependent increased phosphorylation of CD3ζ coincided with inhibition of TCR downmodulation, supporting a positive role for Crk adaptor proteins in TCR-mediated signal amplification.
Collapse
|