Critical role of WNK1 in MYC-dependent early mouse thymocyte development
Abstract
WNK1, a kinase that controls kidney salt homeostasis, also regulates adhesion and migration in CD4+ T cells. Wnk1 is highly expressed in thymocytes, and since migration is important for thymocyte maturation, we investigated a role for WNK1 in mouse thymocyte development. We find that WNK1 is required for the transition of double negative (DN) thymocytes through the b-selection checkpoint and subsequent proliferation and differentiation into double positive (DP) thymocytes. Furthermore, we show that WNK1 negatively regulates LFA1-mediated adhesion and positively regulates CXCL12-induced migration in DN thymocytes. Despite this, migration defects of WNK1-deficient thymocytes do not account for the developmental arrest. Instead, we show that in DN thymocytes WNK1 transduces pre-TCR signals via OXSR1 and STK39 kinases and the SLC12A2 ion co-transporter that are required for post-transcriptional upregulation of MYC and subsequent proliferation and differentiation into DP thymocytes. Thus, a pathway regulating ion homeostasis is a critical regulator of thymocyte development.
Data availability
RNAseq data have been deposited in GEO under accession number GSE136210.
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Analysis of anti-CD3e-induced transcriptional changes in WNK1-deficient thymocytesNCBI Gene Expression Omnibus, GSE136210.
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Expression and regulation of lincRNAs during T cell development and differentiationNCBI Gene Expression Omnibus, GSENCBI Gene Expression Omnibus, GSE48138.
Article and author information
Author details
Funding
Medical Research Council (U117527252)
- Victor LJ Tybulewicz
Francis Crick Institute (FC001194)
- Victor LJ Tybulewicz
Medical Research Council (FC001194)
- Victor LJ Tybulewicz
Wellcome Trust (FC001194)
- Victor LJ Tybulewicz
Cancer Research UK (FC001194)
- Victor LJ Tybulewicz
Biotechnology and Biological Sciences Research Council (BB/L00805X/1)
- Victor LJ Tybulewicz
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were carried out under the authority of a Project Licence granted by the UK Home Office (PPL70/8843).
Copyright
© 2020, Köchl et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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- Immunology and Inflammation
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Background:
Individuals with Down syndrome (DS), the genetic condition caused by trisomy 21 (T21), display clear signs of immune dysregulation, including high rates of autoimmunity and severe complications from infections. Although it is well established that T21 causes increased interferon responses and JAK/STAT signaling, elevated autoantibodies, global immune remodeling, and hypercytokinemia, the interplay between these processes, the clinical manifestations of DS, and potential therapeutic interventions remain ill defined.
Methods:
We report a comprehensive analysis of immune dysregulation at the clinical, cellular, and molecular level in hundreds of individuals with DS, including autoantibody profiling, cytokine analysis, and deep immune mapping. We also report the interim analysis of a Phase II clinical trial investigating the safety and efficacy of the JAK inhibitor tofacitinib through multiple clinical and molecular endpoints.
Results:
We demonstrate multi-organ autoimmunity of pediatric onset concurrent with unexpected autoantibody-phenotype associations in DS. Importantly, constitutive immune remodeling and hypercytokinemia occur from an early age prior to autoimmune diagnoses or autoantibody production. Analysis of the first 10 participants to complete 16 weeks of tofacitinib treatment shows a good safety profile and no serious adverse events. Treatment reduced skin pathology in alopecia areata, psoriasis, and atopic dermatitis, while decreasing interferon scores, cytokine scores, and levels of pathogenic autoantibodies without overt immune suppression.
Conclusions:
JAK inhibition is a valid strategy to treat autoimmune conditions in DS. Additional research is needed to define the effects of JAK inhibition on the broader developmental and clinical hallmarks of DS.
Funding:
NIAMS, Global Down Syndrome Foundation.
Clinical trial number:
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- Immunology and Inflammation
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