1
|
Marković I, Savvides SN. Modulation of Signaling Mediated by TSLP and IL-7 in Inflammation, Autoimmune Diseases, and Cancer. Front Immunol 2020; 11:1557. [PMID: 32849527 PMCID: PMC7396566 DOI: 10.3389/fimmu.2020.01557] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 06/12/2020] [Indexed: 12/30/2022] Open
Abstract
Thymic Stromal Lymphopoietin (TSLP) and Interleukin-7 (IL-7) are widely studied cytokines within distinct branches of immunology. On one hand, TSLP is crucially important for mediating type 2 immunity at barrier surfaces and has been linked to widespread allergic and inflammatory diseases of the airways, skin, and gut. On the other hand, IL-7 operates at the foundations of T-cell and innate lymphoid cell (ILC) development and homeostasis and has been associated with cancer. Yet, TSLP and IL-7 are united by key commonalities in their structure and the structural basis of the receptor assemblies they mediate to initiate cellular signaling, in particular their cross-utilization of IL-7Rα. As therapeutic targeting of TSLP and IL-7 via diverse approaches is reaching advanced stages and in light of the plethora of mechanistic and structural data on receptor signaling mediated by the two cytokines, the time is ripe to provide integrated views of such knowledge. Here, we first discuss the major pathophysiological roles of TSLP and IL-7 in autoimmune diseases, inflammation and cancer. Subsequently, we curate structural and mechanistic knowledge about receptor assemblies mediated by the two cytokines. Finally, we review therapeutic avenues targeting TSLP and IL-7 signaling. We envision that such integrated view of the mechanism, structure, and modulation of signaling assemblies mediated by TSLP and IL-7 will enhance and fine-tune the development of more effective and selective approaches to further interrogate the role of TSLP and IL-7 in physiology and disease.
Collapse
Affiliation(s)
- Iva Marković
- VIB-UGent Center for Inflammation Research, Ghent, Belgium.,Unit for Structural Biology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Savvas N Savvides
- VIB-UGent Center for Inflammation Research, Ghent, Belgium.,Unit for Structural Biology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| |
Collapse
|
2
|
Huo S, Wang L, Zhang Y, Zhang J, Zuo Y, Xu J, Cui D, Li X, Zhong F. Molecular cloning of chicken IL-7 and characterization of its antiviral activity against IBDV in vivo. Poult Sci 2016; 95:2647-2654. [PMID: 27466431 PMCID: PMC5049102 DOI: 10.3382/ps/pew251] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/29/2016] [Indexed: 11/22/2022] Open
Abstract
Mammalian interleukin-7 (IL-7) is able to stimulate lymphocyte proliferation and maturation, and reverse immunosuppression. However, whether poultry IL-7 has similar functions remains unclear. Chicken infectious bursal disease virus (IBDV) causes serious immunosuppression in chicken due to virus-induced immune disorder. Whether chicken IL-7 (chIL-7) has the ability to restore the immunity during IBDV-induced immunosuppression is not clear. To test this, we amplified chIL-7 gene by RT-PCR, prepared recombinant chIL-7 using HEK293T cells and treated the chicken with the chIL-7 prior to IBDV infection. Our results indicate that chIL-7 promoted mouse B cell proliferation in vitro, and significantly reduced virus titer in bursal tissue and chicken morbidity of IBDV-infected chicken. Mechanically, chIL-7 induced chicken lymphocyte proliferation and interferon-γ production, but down-regulated TGF-β expression, suggesting that chIL-7 has the ability to reverse IBDV-induced immunosuppression and might be a potential therapeutic agent for prevention and treatment of infectious bursal disease.
Collapse
Affiliation(s)
- Shanshan Huo
- College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, China
| | - Liyue Wang
- College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, China
| | - Yonghong Zhang
- College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, China
| | - Jianlou Zhang
- College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China
| | - Yuzhu Zuo
- College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China
| | - Jian Xu
- Department of Biotechnology, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China
| | - Dan Cui
- College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China
| | - Xiujin Li
- Department of Biotechnology, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China
| | - Fei Zhong
- College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, China
| |
Collapse
|
3
|
Walsh STR. Structural insights into the common γ-chain family of cytokines and receptors from the interleukin-7 pathway. Immunol Rev 2013; 250:303-16. [PMID: 23046137 DOI: 10.1111/j.1600-065x.2012.01160.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Over the past 13 years, numerous crystal structures of complexes of the common γ-chain (γ(c)) cytokine receptors and their cytokines have been solved. Even with the remarkable progress in the structural biology of γ(c) receptors and their cytokines or interleukins, there are valuable lessons to be learned from the structural and biophysical studies of interleukin-7 (IL-7) and its α-receptor (IL-7Rα) and comparisons with other γ(c) family members. The structure of the IL-7/IL-7Rα complex teaches that interfaces between the γ(c) interleukins and their receptors can vary in size, polarity, and specificity, and that significant conformational changes might be necessary for complexes of interleukins and their receptors to bind the shared, activating γ(c) receptor. Binding, kinetic, and thermodynamic studies of IL-7 and IL-7Rα show that glycosylation and electrostatics can be important to interactions between interleukins and their receptor, even where the glycans and charged residues are distant from the interface. The structure of the IL-7Rα homodimer is a reminder that often-ignored non-activating complexes likely perform roles just as important to signaling as activating complexes. And last but not least, the structural and biophysical studies help explain and potentially treat the diseases caused by aberrant IL-7 signaling.
Collapse
Affiliation(s)
- Scott T R Walsh
- Department of Cell Biology and Molecular Genetics, Institute for Bioscience and Biotechnology Research, W. M. Keck Laboratory for Structural Biology, Rockville, MD, USA.
| |
Collapse
|
4
|
Siewe BT, Kalis SL, Esteves PJ, Zhou T, Knight KL. A novel functional rabbit IL-7 isoform. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2010; 34:828-36. [PMID: 20304004 PMCID: PMC2871983 DOI: 10.1016/j.dci.2010.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 03/08/2010] [Accepted: 03/09/2010] [Indexed: 05/20/2023]
Abstract
IL-7 is required for B cell development in mouse and is a key regulator of T cell development and peripheral T cell homeostasis in mouse and human. Recently, we found that IL-7 is expressed in rabbit bone marrow and in vitro, is required for differentiation of lymphoid progenitors to B and T lineage cells. Herein, we report the identification of a novel rabbit IL-7 isoform, IL-7II. Recombinant IL-7II (rIL-7II) binds lymphocytes via the IL-7R and induces phosphorylation of STAT5. Further, rIL-7II supports proliferation and differentiation of BM progenitor cells into B and T lineage cells. IL7-II is generated by alternative splicing, with an 11 amino acid insertion encoded by a separate exon, exon 2b. Exon 2b is conserved in other lagomorphs, in Perissodactyla, Artiodactyla, and Carnivora, but is absent in mouse and human.
Collapse
Affiliation(s)
- Basile T. Siewe
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, 2160 South First Avenue, Maywood, IL 60153, USA
| | - Susan L. Kalis
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, 2160 South First Avenue, Maywood, IL 60153, USA
| | - Pedro J. Esteves
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, 2160 South First Avenue, Maywood, IL 60153, USA
| | - Tong Zhou
- Department of Cell Biology and Divisions of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Katherine L. Knight
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, 2160 South First Avenue, Maywood, IL 60153, USA
| |
Collapse
|
5
|
McElroy CA, Dohm JA, Walsh STR. Structural and biophysical studies of the human IL-7/IL-7Ralpha complex. Structure 2009; 17:54-65. [PMID: 19141282 DOI: 10.1016/j.str.2008.10.019] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 10/16/2008] [Accepted: 10/22/2008] [Indexed: 01/25/2023]
Abstract
IL-7 and IL-7Ralpha bind the gamma(c) receptor, forming a complex crucial to several signaling cascades leading to the development and homeostasis of T and B cells. We report that the IL-7Ralpha ectodomain uses glycosylation to modulate its binding constants to IL-7, unlike the other receptors in the gamma(c) family. IL-7 binds glycosylated IL-7Ralpha 300-fold more tightly than unglycosylated IL-7Ralpha, and the enhanced affinity is attributed primarily to an accelerated on rate. Structural comparison of IL-7 in complex to both forms of IL-7Ralpha reveals that glycosylation does not participate directly in the binding interface. The SCID mutations of IL-7Ralpha locate outside the binding interface with IL-7, suggesting that the expressed mutations cause protein folding defects in IL-7Ralpha. The IL-7/IL-7Ralpha structures provide a window into the molecular recognition events of the IL-7 signaling cascade and provide sites to target for designing new therapeutics to treat IL-7-related diseases.
Collapse
Affiliation(s)
- Craig A McElroy
- Department of Molecular and Cellular Biochemistry, College of Medicine, Comprehensive Cancer Center, Ohio State University, 467 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA
| | | | | |
Collapse
|
6
|
Barata JT, Silva A, Abecasis M, Carlesso N, Cumano A, Cardoso AA. Molecular and functional evidence for activity of murine IL-7 on human lymphocytes. Exp Hematol 2006; 34:1133-42. [PMID: 16939806 DOI: 10.1016/j.exphem.2006.05.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2006] [Revised: 04/28/2006] [Accepted: 05/01/2006] [Indexed: 10/24/2022]
Abstract
Although interleukin-7 (IL-7) is essential for human and murine lymphopoiesis and homeostasis, clear disparities between these species regarding the role of IL-7 during B-cell development suggest that other, subtler differences may exist. One basic unsolved issue of IL-7 biology concerns cross-species activity, because in contrast to the human ortholog, the ability of murine (m)IL-7 to stimulate human cells remains unresolved. Establishing whether two-way cross-species reactivity occurs is fundamental for evaluating the role of IL-7 in chimeric human-mouse models, which are the most versatile tools for studying human lymphoid development and disease in vivo. Here, we show that mIL-7 triggers the same signaling pathways as human (h)IL-7 in human T cells, promoting similar changes in viability, proliferation, size, and immunophenotype, even at low concentrations. This ability is not confined to T cells, because mIL-7 mediates cell growth and protects human B-cell precursors from dexamethasone-induced apoptosis. Importantly, endogenous mIL-7 produced in the mouse thymic microenvironment stimulates human T cells, because their expansion in chimeric fetal thymic organ cultures is inhibited by a mIL-7-specific neutralizing antibody. Our results demonstrate that mIL-7 affects human lymphocytes and indicate that mouse models of human lymphoid development and disease must integrate the biological effects of endogenous IL-7 on human cells.
Collapse
Affiliation(s)
- Joao T Barata
- Institute of Molecular Medicine, Faculty of Medicine of Lisbon University, Lisbon, Portugal.
| | | | | | | | | | | |
Collapse
|
7
|
Aspinall R. T cell development, ageing and Interleukin-7. Mech Ageing Dev 2006; 127:572-8. [PMID: 16529797 DOI: 10.1016/j.mad.2006.01.016] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Revised: 10/05/2005] [Accepted: 01/16/2006] [Indexed: 10/24/2022]
Abstract
Interleukin-7 (IL-7) is a cytokine with a central role in the development and maintenance of the peripheral T cell pool. In the mouse, expression of the IL-7 gene in the thymus has been carefully followed from gestation onwards throughout the lifespan. One of the features of its expression in the thymus is that it changes with time, declining measurably as the animal ages. This reduction is associated with a decrease in thymic size, cellularity and output. Analysis of transgenic animals carrying either IL-7 or IL-7 receptor transgenes reveals that the intrathymic level of IL-7 has a critical effect on the production of T cells, and that this may not be a linear relationship. This is an important consideration for therapy involving treatment of old animals with IL-7 of which there are reports indicating some rejuvenation of the thymus following IL-7 treatment, which is never complete. The thymus does not appear to return to the size and cellularity seen in youth. Several possible scenarios could account for this, including the inability to maintain IL-7 within defined limits in the thymus during the therapy.
Collapse
Affiliation(s)
- Richard Aspinall
- Department of Immunology, Faculty of Medicine, Imperial College London, London SW10 9NH, UK.
| |
Collapse
|
8
|
Görgün G, van der Spek J, Cosenza L, Menevse A, Foss F. Altered biological activity associated with C-terminal modifications of IL-7. Cytokine 2002; 20:17-22. [PMID: 12441142 DOI: 10.1006/cyto.2002.1974] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Interleukin 7 (IL-7) is a pleiotropic cytokine which plays a role in both T and B cell function as well as in establishment and maintenance of immunological barriers in epithelial tissues. The heterodimeric IL-7 receptor (IL-7R) consists of the p76 IL-7Ralpha subunit and the p64 common gamma (gammac) subunit. Ligand-binding induces signal transduction through tyrosine phosphorylation of the janus (Jak) and src-related kinases as well as by activation of phosphatidinositol-3 kinase (P13-kinase). In an effort to further define the requirements for ligand-receptor interactions and to subsequently develop candidate receptor binding antagonists with selective biological activities, we examined a series of IL-7 mutants in which the carboxy terminal hydrophobic residues were substituted with aliphatic amino acids. In this study we describe abrogation of IL-7 driven proliferation and attenuated phosphotyrosine signaling by IL-7(143) (Trp-Ala) and IL-7(143) (Trp-His) in IL-7R expressing T and B leukemia cells. Decreased phosphorylation of Jak3 kinase by IL-7W143A, IL-7W143P and IL-7W143H suggest that alterations in this region of the carboxyterminal region of IL-7 affects its interaction with the gammac subunit of the IL-7R.
Collapse
Affiliation(s)
- Güllü Görgün
- Hematology, Oncology and Experimental Therapeutics, Tufts New England Medical Center, 750 Washington Street, Boston, MA 02111, USA
| | | | | | | | | |
Collapse
|