scholarly journals Medullary thymic epithelial NF–kB-inducing kinase (NIK)/IKKα pathway shapes autoimmunity and liver and lung homeostasis in mice

2019 ◽  
Vol 116 (38) ◽  
pp. 19090-19097 ◽  
Author(s):  
Hong Shen ◽  
Yewei Ji ◽  
Yi Xiong ◽  
Hana Kim ◽  
Xiao Zhong ◽  
...  
Keyword(s):  
T Cell ◽  
Lung Diseases ◽  
T Cell Development ◽  
Premature Death ◽  
Cell Development ◽  
Thymic Epithelial Cells ◽  
Double Positive ◽  
Central Tolerance ◽  
Autoimmune Destruction

Aberrant T cell development is a pivotal risk factor for autoimmune disease; however, the underlying molecular mechanism of T cell overactivation is poorly understood. Here, we identified NF–κB-inducing kinase (NIK) and IkB kinase α (IKKα) in thymic epithelial cells (TECs) as essential regulators of T cell development. Mouse TEC-specific ablation of either NIK or IKKα resulted in severe T cell-mediated inflammation, injury, and fibrosis in the liver and lung, leading to premature death within 18 d of age. NIK or IKKα deficiency abrogated medullary TEC development, and led to breakdown of central tolerance, production of autoreactive T cells, and fatal autoimmune destruction in the liver and lung. TEC-specific ablation of NIK or IKKα also impaired thymic T cell development from the double-negative through the double-positive stages and inhibited peripheral B cell development. These results unravel a hitherto unrecognized essential role of TEC-intrinsic NIK and IKKα pathways in autoimmunity and T cell-instigated chronic liver and lung diseases.

scholarly journals LAMTOR2 Is Dispensable for T Cell Receptor-Mediated Signaling of Thymocytes but Controls Medullary Thymic Epithelial Cells

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1122-1122
Author(s):  
Lina Wendeler ◽  
Lukas A Huber ◽  
Christoph Klein ◽  
Daniel Kotlarz
Keyword(s):  
T Cell ◽  
Epithelial Cells ◽  
Conflicts Of Interest ◽  
Critical Role ◽  
T Cell Development ◽  
Cell Development ◽  
Conditional Knockout ◽  
Poly I:C ◽  
Thymic Epithelial Cells

Abstract Human LAMTOR2 deficiency is characterized by severe congenital neutropenia, growth failure, partial albinism, as well as B and T cell deficiencies (Bohn et al., Nat Med 2007). To determine the role of the endosomal adaptor LAMTOR2 in T cell development and homeostasis we used conditional knockout mouse models. Mx1-Cre-driven knockout of Lamtor2 resulted in reduction of thymus weight and total thymocyte numbers. Immunophenotyping revealed an impaired T cell development characterized by a partial block at the double negative CD4-CD8- T cell precursor stage after 7 and 21 days of poly I:C injection that induced deletion of the Lamtor2 gene. Since Mx1-Cre-driven knockout does not allow a discrimination between T cell intrinsic and extrinsic effects, we next generated pre-TCRα-iCre conditional knockout mice. In contrast to Mx1-Cre-Lamtor2fl/fl mice, mice with T cell-specific knockout of Lamtor2 showed normal frequencies of total thymocytes and T cell progenitor subsets. Furthermore, LAMTOR2-deficient thymocytes exhibited normal TCR signaling (p-ERK, p-LAT, p-LCK, p-PLCγ, Nur77) and internalization of TCRβ upon stimulation with anti-CD3ε +/- anti-CD28, indicating that LAMTOR2 in T cells is dispensable for thymocyte development. To assess whether T cell developmental defects in Mx1-Cre-Lamtor2fl/fl mice are caused by a dysfunctional thymic epithelium, we analyzed thymic epithelial cells (TECs) after 4 days of poly I:C injection by flow cytometry and detected a reduced ratio of CD45-EpCAM+UEA-1+Ly51- medullary TECs (mTECs) to CD45-EpCAM+UEA-1-Ly51+ cortical TECs in LAMTOR2-deficient mice. Further studies are underway to determine the role of LAMTOR2 in mTECs. Taken together, our findings show that LAMTOR2 is not required for TCR-mediated signaling but plays a critical role in controlling mTEC homeostasis. Disclosures No relevant conflicts of interest to declare.

scholarly journals Thymic Epithelial Cell-Derived IL-15 and IL-15 Receptor α Chain Foster Local Environment for Type 1 Innate Like T Cell Development

2021 ◽  
Vol 12 ◽  
Author(s):  
Huishan Tao ◽  
Lei Li ◽  
Nan-Shih Liao ◽  
Kimberly S. Schluns ◽  
Shirley Luckhart ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Development ◽  
Local Environment ◽  
Cell Development ◽  
Thymic Epithelial Cells ◽  
Thymic Epithelial Cell ◽  
Central Tolerance ◽  
Selection Of

Expression of tissue-restricted antigens (TRAs) in thymic epithelial cells (TECs) ensures negative selection of highly self-reactive T cells to establish central tolerance. Whether some of these TRAs could exert their canonical biological functions to shape thymic environment to regulate T cell development is unclear. Analyses of publicly available databases have revealed expression of transcripts at various levels of many cytokines and cytokine receptors such as IL-15, IL-15Rα, IL-13, and IL-23a in both human and mouse TECs. Ablation of either IL-15 or IL-15Rα in TECs selectively impairs type 1 innate like T cell, such as iNKT1 and γδT1 cell, development in the thymus, indicating that TECs not only serve as an important source of IL-15 but also trans-present IL-15 to ensure type 1 innate like T cell development. Because type 1 innate like T cells are proinflammatory, our data suggest the possibility that TEC may intrinsically control thymic inflammatory innate like T cells to influence thymic environment.

scholarly journals Thymic Epithelial Cells Contribute to Thymopoiesis and T Cell Development

2020 ◽  
Vol 10 ◽  
Author(s):  
Hong-Xia Wang ◽  
Wenrong Pan ◽  
Lei Zheng ◽  
Xiao-Ping Zhong ◽  
Liang Tan ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Epithelial Cells ◽  
New Technology ◽  
T Cell Development ◽  
Cell Development ◽  
Lymphoid Organ ◽  
Thymic Epithelial Cells ◽  
Thymic Involution ◽  
Central Tolerance

The thymus is the primary lymphoid organ responsible for the generation and maturation of T cells. Thymic epithelial cells (TECs) account for the majority of thymic stromal components. They are further divided into cortical and medullary TECs based on their localization within the thymus and are involved in positive and negative selection, respectively. Establishment of self-tolerance in the thymus depends on promiscuous gene expression (pGE) of tissue-restricted antigens (TRAs) by TECs. Such pGE is co-controlled by the autoimmune regulator (Aire) and forebrain embryonic zinc fingerlike protein 2 (Fezf2). Over the past two decades, research has found that TECs contribute greatly to thymopoiesis and T cell development. In turn, signals from T cells regulate the differentiation and maturation of TECs. Several signaling pathways essential for the development and maturation of TECs have been discovered. New technology and animal models have provided important observations on TEC differentiation, development, and thymopoiesis. In this review, we will discuss recent advances in classification, development, and maintenance of TECs and mechanisms that control TEC functions during thymic involution and central tolerance.

scholarly journals Delta-like 4 is indispensable in thymic environment specific for T cell development

2008 ◽  
Vol 205 (11) ◽  
pp. 2507-2513 ◽  
Author(s):  
Katsuto Hozumi ◽  
Carolina Mailhos ◽  
Naoko Negishi ◽  
Ken-ichi Hirano ◽  
Takashi Yahata ◽  
...  
Keyword(s):  
T Cell ◽  
Notch Signaling ◽  
Cell Fate ◽  
T Cell Development ◽  
Cell Development ◽  
Thymic Epithelial Cells ◽  
Hematopoietic Progenitors ◽  
Double Positive

The thymic microenvironment is required for T cell development in vivo. However, in vitro studies have shown that when hematopoietic progenitors acquire Notch signaling via Delta-like (Dll)1 or Dll4, they differentiate into the T cell lineage in the absence of a thymic microenvironment. It is not clear, however, whether the thymus supports T cell development specifically by providing Notch signaling. To address this issue, we generated mice with a loxP-flanked allele of Dll4 and induced gene deletion specifically in thymic epithelial cells (TECs). In the thymus of mutant mice, the expression of Dll4 was abrogated on the epithelium, and the proportion of hematopoietic cells bearing the intracellular fragment of Notch1 (ICN1) was markedly decreased. Corresponding to this, CD4 CD8 double-positive or single-positive T cells were not detected in the thymus. Further analysis showed that the double-negative cell fraction was lacking T cell progenitors. The enforced expression of ICN1 in hematopoietic progenitors restored thymic T cell differentiation, even when the TECs were deficient in Dll4. These results indicate that the thymus-specific environment for determining T cell fate indispensably requires Dll4 expression to induce Notch signaling in the thymic immigrant cells.

scholarly journals Fine-tuning of β-catenin in thymic epithelial cells is required for postnatal T cell development

2021 ◽  
Author(s):  
Sayumi Fujimori ◽  
Izumi Ohigashi ◽  
Hayato Abe ◽  
M Mark Taketo ◽  
Yousuke Takahama ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Epithelial Cells ◽  
T Cell Development ◽  
Cell Development ◽  
Fine Tuning ◽  
Thymic Epithelial Cells ◽  
Loss Of Function ◽  
Thymic Epithelium

In the thymus, the thymic epithelium provides a microenvironment essential for the development of functionally competent and self-tolerant T cells. Previous findings showed that modulation of Wnt/β-catenin signaling in thymic epithelial cells (TECs) disrupts embryonic thymus organogenesis. However, the role of β-catenin in TECs for postnatal T cell development remains to be elucidated. Here, we analyzed gain-of function (GOF) and loss-of-function (LOF) of β-catenin highly specific in TECs. We found that GOF of β-catenin in TECs results in severe thymic dysplasia and T cell deficiency beginning from the embryonic period. By contrast, LOF of β-catenin in TECs reduces the number of cortical TECs and thymocytes modestly and only postnatally. These results indicate that fine-tuning of β-catenin expression within a permissive range is required for TECs to generate an optimal microenvironment to support postnatal T cell development.

scholarly journals CD45-null transgenic mice reveal a positive regulatory role for CD45 in early thymocyte development, in the selection of CD4+CD8+ thymocytes, and B cell maturation.

1996 ◽  
Vol 183 (4) ◽  
pp. 1707-1718 ◽  
Author(s):  
K F Byth ◽  
L A Conroy ◽  
S Howlett ◽  
A J Smith ◽  
J May ◽  
...  
Keyword(s):  
Signal Transduction ◽  
T Cell ◽  
B Cells ◽  
Transgenic Mice ◽  
B Cell ◽  
T Cell Development ◽  
Cell Development ◽  
Cross Linking ◽  
Thymocyte Development ◽  
Double Positive

The CD45 transmembrane glycoprotein has been shown to be a protein phosphotyrosine phosphatase and to be important in signal transduction in T and B lymphocytes. We have employed gene targeting to create a strain of transgenic mice that completely lacks expression of all isoforms of CD45. The spleens from CD45-null mice contain approximately twice the number of B cells and one fifth the number of T cells found in normal controls. The increase in B cell numbers is due to the specific expansion of two B cell subpopulations that express high levels of immunoglobulin (IgM) staining. T cell development is significantly inhibited in CD45-null animals at two distinct stages. The efficiency of the development of CD4-CD8- thymocytes into CD4+ CD8+ thymocytes is reduced by twofold, subsequently the frequency of successful maturation of the double positive population into mature, single positive thymocytes is reduced by a further four- to fivefold. In addition, we demonstrate that CD45-null thymocytes are severely impaired in their apoptotic response to cross-linking signals via T cell receptor (TCR) in fetal thymic organ culture. In contrast, apoptosis can be induced normally in CD45-null thymocytes by non-TCR-mediated signals. Since both positive and negative selection require signals through the TCR complex, these findings suggest that CD45 is an important regulator of signal transduction via the TCR complex at multiple stages of T cell development. CD45 is absolutely required for the transmission of mitogenic signals via IgM and IgD. By contrast, CD45-null B cells proliferate as well as wild-type cells to CD40-mediated signals. The proliferation of B cells in response to CD38 cross-linking is significantly reduced but not abolished by the CD45-null mutation. We conclude that CD45 is not required at any stage during the generation of mature peripheral B cells, however its loss reveals a previously unrecognized role for CD45 in the regulation of certain subpopulations of B cells.

scholarly journals Role of Hormonal Circuitry Upon T Cell Development in Chagas Disease: Possible Implications on T Cell Dysfunctions

2018 ◽  
Vol 9 ◽  
Author(s):  
Ana Rosa Pérez ◽  
Alexandre Morrot ◽  
Vinicius Frias Carvalho ◽  
Juliana de Meis ◽  
Wilson Savino
Keyword(s):  
T Cell ◽  
Chagas Disease ◽  
T Cell Development ◽  
Cell Development

The role of Tec family kinases in T cell development and function

2003 ◽  
Vol 191 (1) ◽  
pp. 119-138 ◽  
Author(s):  
Julie A. Lucas ◽  
Andrew T. Miller ◽  
Luana O. Atherly ◽  
Leslie J. Berg
Keyword(s):  
T Cell ◽  
T Cell Development ◽  
Cell Development ◽  
And Function

Altered thymocyte and T cell development in neonatal mice with hyperoxia-induced lung injury

2018 ◽  
Vol 46 (4) ◽  
pp. 441-449
Author(s):  
Sowmya Angusamy ◽  
Tamer Mansour ◽  
Mohammed Abdulmageed ◽  
Rachel Han ◽  
Brian C. Schutte ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Lung Injury ◽  
T Cell Development ◽  
Adaptive Immune System ◽  
Cell Development ◽  
Thymocyte Development ◽  
Double Positive ◽  
Neonatal Mice ◽  
Single Positive

Abstract Background: The adaptive immune system of neonates is relatively underdeveloped. The thymus is an essential organ for adaptive T cell development and might be affected during the natural course of oxygen induced lung injury. The effect of prolonged hyperoxia on the thymus, thymocyte and T cell development, and its proliferation has not been studied extensively. Methods: Neonatal mice were exposed to 85% oxygen (hyperoxia) or room air (normoxia) up to 28 days. Flow cytometry using surface markers were used to assay for thymocyte development and proliferation. Results: Mice exposed to prolonged hyperoxia had evidence of lung injury associated alveolar simplification, a significantly lower mean weight, smaller thymic size, lower mean thymocyte count and higher percentage of apoptotic thymocytes. T cells subpopulation in the thymus showed a significant reduction in the count and proliferation of double positive and double negative T cells. There was a significant reduction in the count and proliferation of single positive CD4+ and CD8+ T cells. Conclusions: Prolonged hyperoxia in neonatal mice adversely affected thymic size, thymocyte count and altered the distribution of T cells sub-populations. These results are consistent with the hypothesis that prolonged hyperoxia causes defective development of T cells in the thymus.

Sign in / Sign up

Export Citation Format

Share Document