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Risemberg EL, Smeekens JM, Cruz Cisneros MC, Hampton BK, Hock P, Linnertz CL, Miller DR, Orgel K, Shaw GD, Manuel de Villena FP, Burks AW, Valdar W, Kulis MD, Ferris MT. A mutation in Themis contributes to anaphylaxis severity following oral peanut challenge in CC027 mice. J Allergy Clin Immunol 2024:S0091-6749(24)00411-1. [PMID: 38670234 DOI: 10.1016/j.jaci.2024.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 03/12/2024] [Accepted: 03/22/2024] [Indexed: 04/28/2024]
Abstract
BACKGROUND The development of peanut allergy is due to a combination of genetic and environmental factors, although specific genes have proven difficult to identify. Previously, we reported that peanut-sensitized CC027/GeniUnc (CC027) mice develop anaphylaxis upon oral challenge to peanut, unlike C3H/HeJ (C3H) mice. OBJECTIVE To determine the genetic basis of orally-induced anaphylaxis to peanut in CC027 mice. METHODS A genetic mapping population between CC027 and C3H mice was designed to identify the genetic factors that drive oral anaphylaxis. A total of 356 CC027xC3H backcrossed mice were generated, sensitized to peanut, then challenged to peanut by oral gavage. Anaphylaxis and peanut-specific IgE were quantified for all mice. T-cell phenotyping was conducted on CC027 and five additional CC strains. RESULTS Anaphylaxis to peanut was absent in 77% of backcrossed mice, with 19% showing moderate anaphylaxis, and 4% having severe anaphylaxis. A total of eight genetic loci were associated with variation in response to peanut challenge, six associated with anaphylaxis (temperature decrease) and two associated with peanut-specific IgE levels. There were two major loci that impacted multiple aspects of the severity of acute anaphylaxis, at which the CC027 allele was associated with worse outcome. At one of these loci, CC027 has a private genetic variant in the Themis (thymocyte-expressed molecule involved in selection) gene. Consistent with Themis' described functions, we found that CC027 have more immature T cells with fewer CD8+, CD4+, and CD4+CD25+CD127- regulatory T cells. CONCLUSION Our results demonstrate a key role for Themis in the orally-reactive CC027 mouse model of peanut allergy.
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Affiliation(s)
- Ellen L Risemberg
- Curriculum in Bioinformatics and Computational Biology, UNC Chapel Hill; Department of Genetics, UNC Chapel Hill
| | - Johanna M Smeekens
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
| | - Marta C Cruz Cisneros
- Department of Genetics, UNC Chapel Hill; Curriculum in Genetics and Molecular Biology, UNC Chapel Hill
| | - Brea K Hampton
- Department of Genetics, UNC Chapel Hill; Curriculum in Genetics and Molecular Biology, UNC Chapel Hill
| | | | | | | | - Kelly Orgel
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
| | - Ginger D Shaw
- Department of Genetics, UNC Chapel Hill; Lineberger Comprehensive Cancer Center, UNC Chapel Hill
| | | | - A Wesley Burks
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
| | - William Valdar
- Department of Genetics, UNC Chapel Hill; Lineberger Comprehensive Cancer Center, UNC Chapel Hill
| | - Michael D Kulis
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
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Risemberg EL, Smeekens JM, Cisneros MCC, Hampton BK, Hock P, Linnertz CL, Miller DR, Orgel K, Shaw GD, de Villena FPM, Burks AW, Valdar W, Kulis MD, Ferris MT. A mutation in Themis contributes to peanut-induced oral anaphylaxis in CC027 mice. bioRxiv 2023:2023.09.13.557467. [PMID: 37745496 PMCID: PMC10515941 DOI: 10.1101/2023.09.13.557467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Background The development of peanut allergy is due to a combination of genetic and environmental factors, although specific genes have proven difficult to identify. Previously, we reported that peanut-sensitized CC027/GeniUnc (CC027) mice develop anaphylaxis upon oral challenge to peanut, unlike C3H/HeJ (C3H) mice. Objective To determine the genetic basis of orally-induced anaphylaxis to peanut in CC027 mice. Methods A genetic mapping population between CC027 and C3H mice was designed to identify the genetic factors that drive oral anaphylaxis. A total of 356 CC027xC3H backcrossed mice were generated, sensitized to peanut, then challenged to peanut by oral gavage. Anaphylaxis and peanut-specific IgE were quantified for all mice. T-cell phenotyping was conducted on CC027 and five additional CC strains. Results Anaphylaxis to peanut was absent in 77% of backcrossed mice, with 19% showing moderate anaphylaxis, and 4% having severe anaphylaxis. A total of eight genetic loci were associated with variation in response to peanut challenge, six associated with anaphylaxis (temperature decrease) and two associated with peanut-specific IgE levels. There were two major loci that impacted multiple aspects of the severity of acute anaphylaxis, at which the CC027 allele was associated with worse outcome. At one of these loci, CC027 has a private genetic variant in the Themis (thymocyte-expressed molecule involved in selection) gene. Consistent with Themis' described functions, we found that CC027 have more immature T cells with fewer CD8+, CD4+, and CD4+CD25+CD127- regulatory T cells. Conclusion Our results demonstrate a key role for Themis in the orally-reactive CC027 mouse model of peanut allergy.
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Affiliation(s)
- Ellen L. Risemberg
- Curriculum in Bioinformatics and Computational Biology, UNC Chapel Hill
- Department of Genetics, UNC Chapel Hill
| | - Johanna M. Smeekens
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
| | - Marta C. Cruz Cisneros
- Department of Genetics, UNC Chapel Hill
- Curriculum in Genetics and Molecular Biology, UNC Chapel Hill
| | - Brea K. Hampton
- Department of Genetics, UNC Chapel Hill
- Curriculum in Genetics and Molecular Biology, UNC Chapel Hill
| | | | | | | | - Kelly Orgel
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
| | - Ginger D. Shaw
- Department of Genetics, UNC Chapel Hill
- Lineberger Comprehensive Cancer Center, UNC Chapel Hill
| | | | - A. Wesley Burks
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
| | - William Valdar
- Department of Genetics, UNC Chapel Hill
- Lineberger Comprehensive Cancer Center, UNC Chapel Hill
| | - Michael D. Kulis
- Department of Pediatrics, Division of Allergy and Immunology, UNC Chapel Hill
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Tang J, Jia X, Li J, Dong J, Wang J, Li W, Zhu Y, Hu Y, Hou B, Lin C, Cong Y, Ren T, Yan C, Yang H, Lai Q, Zheng H, Bao Y, Gautam N, Wang HR, Xu B, Chen XL, Li Q, Gascoigne NRJ, Fu G. Themis suppresses the effector function of CD8 + T cells in acute viral infection. Cell Mol Immunol 2023; 20:512-524. [PMID: 36977779 DOI: 10.1038/s41423-023-00997-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 03/06/2023] [Indexed: 03/30/2023] Open
Abstract
CD8+ T cells play a central role in antiviral immune responses. Upon infection, naive CD8+ T cells differentiate into effector cells to eliminate virus-infected cells, and some of these effector cells further differentiate into memory cells to provide long-term protection after infection is resolved. Although extensively investigated, the underlying mechanisms of CD8+ T-cell differentiation remain incompletely understood. Themis is a T-cell-specific protein that plays critical roles in T-cell development. Recent studies using Themis T-cell conditional knockout mice also demonstrated that Themis is required to promote mature CD8+ T-cell homeostasis, cytokine responsiveness, and antibacterial responses. In this study, we used LCMV Armstrong infection as a probe to explore the role of Themis in viral infection. We found that preexisting CD8+ T-cell homeostasis defects and cytokine hyporesponsiveness do not impair viral clearance in Themis T-cell conditional knockout mice. Further analyses showed that in the primary immune response, Themis deficiency promoted the differentiation of CD8+ effector cells and increased their TNF and IFNγ production. Moreover, Themis deficiency impaired memory precursor cell (MPEC) differentiation but promoted short-lived effector cell (SLEC) differentiation. Themis deficiency also enhanced effector cytokine production in memory CD8+ T cells while impairing central memory CD8+ T-cell formation. Mechanistically, we found that Themis mediates PD-1 expression and its signaling in effector CD8+ T cells, which explains the elevated cytokine production in these cells when Themis is disrupted.
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Affiliation(s)
- Jian Tang
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Xian Jia
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Jian Li
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Junchen Dong
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Jiayu Wang
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Wanyun Li
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Yuzhen Zhu
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Yanyan Hu
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Bowen Hou
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Chunjie Lin
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Yu Cong
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Tong Ren
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Changsheng Yan
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Hongying Yang
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Qian Lai
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Haiping Zheng
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Yuzhou Bao
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Namrata Gautam
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Hong-Rui Wang
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Bing Xu
- Department of Hematology, The First Affiliated Hospital and Institute of Hematology, School of Medicine, Xiamen University, Xiamen, China
| | - Xiao Lei Chen
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China.
| | - Qing Li
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China.
| | - Nicholas R J Gascoigne
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
| | - Guo Fu
- State Key Laboratory of Cellular Stress Biology, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China.
- Department of Hematology, The First Affiliated Hospital and Institute of Hematology, School of Medicine, Xiamen University, Xiamen, China.
- Cancer Research Center of Xiamen University, Xiamen, China.
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Abstract
During thymocyte development at the double positive stage, thymocytes are subjected to a TCR quality check process termed "thymocyte selection." TCRs with proper binding capabilities to MHC molecules (with self-peptide) are able to transduce cell survival signals and allow the continuing of development to single positive T cells. It has been known that TCRs in DP cells can transduce signals with higher efficiency than peripheral mature T cells, even though they share most of the signaling components. Recent studies have revealed some thymocyte-specific signaling modulators including Themis and Tespa1. The activation of TCR signaling during positive selection results in the activation of several key transcription factors and extensive gene expression change, which has been revealed by newly developed systemic transcriptome analysis tools, and could be used for the evaluation of positive selection process. The fate determination postpositive selection is also governed on the epigenetic level including both DNA methylation and histone modifications.
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Affiliation(s)
- Jun Lyu
- Institute of Immunology, Zhejiang University School of Medicine, Hangzhou, China
| | - Lie Wang
- Institute of Immunology, Zhejiang University School of Medicine, Hangzhou, China
| | - Linrong Lu
- Institute of Immunology, Zhejiang University School of Medicine, Hangzhou, China; Zhejiang University-University of Edinburgh Institute, Zhejiang University, Haining, China; Department of Dermatology and Rheumatology in Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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Mehta M, Brzostek J, Chen EW, Tung DWH, Chen S, Sankaran S, Yap J, Rybakin V, Gascoigne NRJ. Themis-associated phosphatase activity controls signaling in T cell development. Proc Natl Acad Sci U S A 2018; 115:E11331-40. [PMID: 30413615 DOI: 10.1073/pnas.1720209115] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Thymocyte-expressed molecule involved in selection (Themis) regulates T cell selection. Absence of Themis leads to severely reduced numbers of CD4 and CD8 T cells, indicating a defect in T cell selection. The molecular mechanism of Themis involvement is not clear. Themis was shown to bind to Src-homology domain containing phosphatase-1 (Shp1), which is a known negative regulator of T cell receptor signaling. Here, using a very sensitive technique to measure phosphatase activity from immunoprecipitated proteins, we find that Themis positively regulates Shp1 phosphatase activity in thymocytes. Shp1 activity is reduced in the absence of Themis, thus providing an explanation for why Themis-deficient thymocytes respond more strongly to positive-selecting ligands, resulting in fewer thymocytes reaching maturity. Thymocyte-expressed molecule involved in selection (Themis) has been shown to be important for T cell selection by setting the threshold for positive versus negative selection. Themis interacts with the protein tyrosine phosphatase (PTP) Src-homology domain containing phosphatase-1 (Shp1), a negative regulator of the T cell receptor (TCR) signaling cascade. However, how Themis regulates Shp1 is still not clear. Here, using a very sensitive phosphatase assay on ex vivo thymocytes, we have found that Themis enhances Shp1 phosphatase activity by increasing its phosphorylation. This positive regulation of Shp1 activity by Themis is found in thymocytes, but not in peripheral T cells. Shp1 activity is modulated by different affinity peptide MHC ligand binding in thymocytes. Themis is also associated with phosphatase activity, due to its constitutive interaction with Shp1. In the absence of Shp1 in thymocytes, Themis interacts with Shp2, which leads to almost normal thymic development in Shp1 conditional knockout (cKO) mice. Double deletion of both Themis and Shp1 leads to a thymic phenotype similar to that of Themis KO. These findings demonstrate unequivocally that Themis positively regulates Shp1 phosphatase activity in TCR-mediated signaling in developing thymocytes.
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Abstract
Thymocyte selection involves the positive and negative selection of the repertoire of T cell receptors (TCRs) such that the organism does not suffer autoimmunity, yet has the benefit of the ability to recognize any invading pathogen. The signal transduced through the TCR is translated into a number of different signaling cascades that result in transcription factor activity in the nucleus and changes to the cytoskeleton and motility. Negative selection involves inducing apoptosis in thymocytes that express strongly self-reactive TCRs, whereas positive selection must induce survival and differentiation programs in cells that are more weakly self-reactive. The TCR recognition event is analog by nature, but the outcome of signaling is not. A large number of molecules regulate the strength of the TCR-derived signal at various points in the cascades. This review discusses the various factors that can regulate the strength of the TCR signal during thymocyte development.
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Affiliation(s)
- Nicholas R J Gascoigne
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, and Immunology Program, National University of Singapore, Singapore 11759;
| | - Vasily Rybakin
- Laboratory of Immunobiology, REGA Institute, Department of Microbiology and Immunology, KU Leuven, Leuven 3000, Belgium
| | - Oreste Acuto
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Joanna Brzostek
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, and Immunology Program, National University of Singapore, Singapore 11759;
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Sánchez N, Vergés A, Peteiro C, Sutherland JE, Brodie J. Diversity of bladed Bangiales (Rhodophyta) in western Mediterranean: recognition of the genus Themis and descriptions of T. ballesterosii sp. nov., T. iberica sp. nov., and Pyropia parva sp. nov. J Phycol 2014; 50:908-929. [PMID: 26988645 DOI: 10.1111/jpy.12223] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 07/02/2014] [Indexed: 06/05/2023]
Abstract
The diversity of the bladed species of the red algal order Bangiales from the Iberian Mediterranean shores has been reassessed after a detailed study of this region. Prior to this study, 11 bladed species of Bangiales had been reported from Mediterranean waters: Porphyra atropurpurea, P. cordata, P. coriacea, P. dioica, P. linearis, P. purpurea, P. umbilicalis, Pyropia leucosticta, Pyropia koreana (as P. olivii), Py. elongata (as P. rosengurttii) and Py. suborbiculata. A combined analysis of the nuclear nSSU and the plastid rbcL genes together with detailed morphological studies has confirmed the presence of species within the genera Porphyra and Pyropia and also revealed a third, undescribed genus, Themis gen. nov. Porphyra linearis, Pyropia elongata and the introduced Pyropia koreana had been previously listed for the Mediterranean and were recorded in this study. An additional four species, including the introduced Pyropia suborbiculata and three new species: Pyropia parva sp. nov., Themis ballesterosii sp. nov., and Themis iberica sp. nov. were also observed. Hence, most of the Porphyra species traditionally reported along these shores were not reported in this survey. This new floristic Bangiales composition confirms the importance of the Mediterranean basin as a hotspot for biodiversity, possible endemics of ancient origin and high proportion of introductions. Our data also continue to confirm the extent of Bangiales diversity at regional and worldwide levels.
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Affiliation(s)
- Noemí Sánchez
- Departament de Ciències Ambientals, Facultat de Ciències, Universitat de Girona, Girona, 17071, Spain
| | - Alba Vergés
- Departament de Ciències Ambientals, Facultat de Ciències, Universitat de Girona, Girona, 17071, Spain
| | - César Peteiro
- Instituto Español de Oceanografía (IEO), Centro Oceanográfico de Santander, Santander, 39080, Spain
| | - Judith E Sutherland
- School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Juliet Brodie
- Department of Life Sciences, Natural History Museum, London, SW7 5BD, UK
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Fu G, Rybakin V, Brzostek J, Paster W, Acuto O, Gascoigne NRJ. Fine-tuning T cell receptor signaling to control T cell development. Trends Immunol 2014; 35:311-8. [PMID: 24951034 DOI: 10.1016/j.it.2014.05.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 04/24/2014] [Accepted: 05/12/2014] [Indexed: 01/23/2023]
Abstract
T cell development from immature CD4(+)CD8(+) double-positive (DP) thymocytes to the mature CD4 or CD8 single-positive (SP) stage requires proper T cell receptor (TCR) signaling. The current working model of thymocyte development is that the strength of the TCR-mediated signal - from little-or-none, through intermediate, to strong - received by the immature cells determines whether they will undergo death by neglect, positive selection, or negative selection, respectively. In recent years, several developmentally regulated, stage-specifically expressed proteins and miRNAs have been found that act like fine-tuners for signal transduction and propagation downstream of the TCR. This allows them to govern thymocyte positive selection. Here, we summarize recent findings on these molecules and suggest new concepts of TCR positive-selection signaling.
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Affiliation(s)
- Guo Fu
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Vasily Rybakin
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117597
| | - Joanna Brzostek
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117597
| | - Wolfgang Paster
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Oreste Acuto
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Nicholas R J Gascoigne
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117597.
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