Ahmet Eken1, Murat Cansever2, Ido Somekh3, Yoko Mizoguchi3, Natalia Zietara3, Fatma Zehra Okus4, Serife Erdem4, Halit Canatan4, Sefika Akyol2, Alper Ozcan2, Musa Karakukcu2, Sebastian Hollizeck3, Meino Rohlfs3, Ekrem Unal5, Christoph Klein3, Turkan Patiroglu2. 1. Faculty of Medicine, Department of Medical Biology, Genome and Stem Cell Center (GENKOK), Erciyes University, 38030, Melikgazi, Kayseri, Turkey. ahmet.eken@gmail.com. 2. Faculty of Medicine, Department of Pediatrics, Division of Pediatric Hematology-Oncology, Erciyes University, 38030, Melikgazi, Kayseri, Turkey. 3. Dr von Hauner Children's Hospital, Department of Pediatrics, University Hospital, LMU Munich, Munich, Germany. 4. Faculty of Medicine, Department of Medical Biology, Genome and Stem Cell Center (GENKOK), Erciyes University, 38030, Melikgazi, Kayseri, Turkey. 5. Faculty of Medicine, Department of Pediatrics, Division of Pediatric Hematology-Oncology, Erciyes University, 38030, Melikgazi, Kayseri, Turkey. drekremunal@yahoo.com.tr.
Abstract
PURPOSE: Interleukin-2-inducible T cell kinase (ITK) is an important mediator of T cell receptor signaling. Loss of function mutations in ITK results in hypogammaglobulinemia and CD4+ T cell loss in humans, and the patients often present with EBV-associated B cell lymphoproliferative syndrome. Itk-deficient mice show loss of T cell naivety, impaired cytolytic activity of CD8+ T cells, and defects in CD4+ T cell lineage choice decisions. In mice, Itk mutations were shown to affect Th17-Treg lineage choice in favor of the latter. In this study, we explored whether human ITK reciprocally regulates Th17-Treg balance as its murine ortholog. METHODS: Whole Exome Sequencing was used to identify the mutation. ITK-deficient peripheral blood lymphocytes were characterized by FACSAria III-based flow cytometric assays with respect to proliferation, apoptosis, cytokine production, and innate lymphoid cell (ILC) frequency. Sorted T cells from healthy donors were exposed to ibrutinib, an irreversible ITK inhibitor, to assess ITK's contribution to Th17 and Treg cell generation and functions. RESULTS: In this study, we report a child with a novel ITK mutation who showed impaired CD3/CD28 induced proliferation in T cells. ITK-mutant cells were more apoptotic irrespective of TCR activation. More importantly, T cells produced less Th17-associated cytokines IL-17A, IL-22, and GM-CSF. Conversely, Th1-associated IFN-γ production was increased. An irreversible inhibitor of ITK, ibrutinib, blocked ex vivo Th17 generation and IL-17A production, conversely augmented FOXP3 expression only at low doses in Treg cultures. Finally, we analyzed peripheral ILC populations and observed a relative decrease in ILC2 and ILC3 frequency in our ITK-deficient patient. CONCLUSIONS: To our knowledge, this is the first report showing that both genetic and chemical inhibition of ITK result in reduced Th17 generation and function in humans. We also report, for the first time, a reduction in ILC2 and ILC3 populations in an ITK-deficient human patient.
PURPOSE:Interleukin-2-inducible T cell kinase (ITK) is an important mediator of T cell receptor signaling. Loss of function mutations in ITK results in hypogammaglobulinemia and CD4+ T cell loss in humans, and the patients often present with EBV-associated B cell lymphoproliferative syndrome. Itk-deficient mice show loss of T cell naivety, impaired cytolytic activity of CD8+ T cells, and defects in CD4+ T cell lineage choice decisions. In mice, Itk mutations were shown to affect Th17-Treg lineage choice in favor of the latter. In this study, we explored whether humanITK reciprocally regulates Th17-Treg balance as its murine ortholog. METHODS: Whole Exome Sequencing was used to identify the mutation. ITK-deficient peripheral blood lymphocytes were characterized by FACSAria III-based flow cytometric assays with respect to proliferation, apoptosis, cytokine production, and innate lymphoid cell (ILC) frequency. Sorted T cells from healthy donors were exposed to ibrutinib, an irreversible ITK inhibitor, to assess ITK's contribution to Th17 and Treg cell generation and functions. RESULTS: In this study, we report a child with a novel ITK mutation who showed impaired CD3/CD28 induced proliferation in T cells. ITK-mutant cells were more apoptotic irrespective of TCR activation. More importantly, T cells produced less Th17-associated cytokines IL-17A, IL-22, and GM-CSF. Conversely, Th1-associated IFN-γ production was increased. An irreversible inhibitor of ITK, ibrutinib, blocked ex vivo Th17 generation and IL-17A production, conversely augmented FOXP3 expression only at low doses in Treg cultures. Finally, we analyzed peripheral ILC populations and observed a relative decrease in ILC2 and ILC3 frequency in our ITK-deficient patient. CONCLUSIONS: To our knowledge, this is the first report showing that both genetic and chemical inhibition of ITK result in reduced Th17 generation and function in humans. We also report, for the first time, a reduction in ILC2 and ILC3 populations in an ITK-deficient humanpatient.
Authors: E M Schaeffer; G S Yap; C M Lewis; M J Czar; D W McVicar; A W Cheever; A Sher; P L Schwartzberg Journal: Nat Immunol Date: 2001-12 Impact factor: 25.606
Authors: E M Schaeffer; J Debnath; G Yap; D McVicar; X C Liao; D R Littman; A Sher; H E Varmus; M J Lenardo; P L Schwartzberg Journal: Science Date: 1999-04-23 Impact factor: 47.728
Authors: Lu Huang; Kaixiong Ye; Michael C McGee; Natalie F Nidetz; Jessica P Elmore; Candice B Limper; Teresa L Southard; David G Russell; Avery August; Weishan Huang Journal: Front Immunol Date: 2020-01-24 Impact factor: 7.561