A chimeric type II/type I interleukin-1 receptor can mediate interleukin-1 induction of gene expression in T cells

In autoimmune polyglandular syndromes (APS), several organ-specific autoimmune diseases are clustered. Although APS type I is caused by loss of central tolerance, the etiology of APS type II (APS-II) is currently unknown. However, in several murine models, depletion of CD4+ CD25+ regulatory T cells (Tregs) causes a syndrome resembling human APS-II with multiple endocrinopathies. Therefore, we hypothesized that loss of active suppression in the periphery could be a hallmark of this syndrome. Tregs from peripheral blood of APS-II, control patients with single autoimmune endocrinopathies, and normal healthy donors showed no differences in quantity (except for patients with isolated autoimmune diseases), in functionally important surface markers, or in apoptosis induced by growth factor withdrawal. Strikingly, APS-II Tregs were defective in their suppressive capacity. The defect was persistent and not due to responder cell resistance. These data provide novel insights into the pathogenesis of APS-II and possibly human autoimmunity in general.

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Structure of the two promoters of the human lck gene: differential accumulation of two classes of lck transcripts in T cells

Molecular and Cellular Biology ◽

10.1128/mcb.9.5.2173-2180.1989 ◽

1989 ◽

Vol 9 (5) ◽

pp. 2173-2180

Author(s):

T Takadera ◽

S Leung ◽

A Gernone ◽

Y Koga ◽

Y Takihara ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cell Lines ◽

Carcinoma Cell ◽

Human Peripheral Blood ◽

Specific Gene ◽

Type I ◽

Type Ii ◽

Carcinoma Cell Lines ◽

Human T Cell

The human T-cell- or lymphocyte-specific gene, lck, encodes a tyrosine kinase and is a member of the src family. In this report we demonstrate that there are two classes of human lck transcripts (types I and II), containing different 5'-untranslated regions, which are expressed from two distinct promoters. No apparent sequence similarity was observed between the 5'-flanking regions of the two promoters. The expression of lck in human T-cell leukemia and carcinoma cell lines and in human peripheral blood T lymphocytes was examined by S1 nuclease and primer extension mapping and by Northern (RNA) blot analysis of total cellular RNA. The following results were obtained. (i) Two RNA start sites in the downstream promoter were used to generate type I transcripts. (ii) The major human type I start site has not been described for the mouse. (iii) At least five RNA start sites in the upstream promoter were used to generate type II transcripts. (iv) In T cells and in two colon carcinoma cell lines, type II transcripts were present in higher amounts than type I transcripts. (v) In T cells treated with phytohemagglutinin, tetradecanoylphorbol acetate, and cyclosporin A, the modulation of lck expression was associated primarily with changes in levels of type II transcripts. The above results suggest that the two human lck promoters are utilized differentially and may be regulated independently during certain physiological states.

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Therapeutic Strategies for Diabetes: Immune Modulation in Pancreatic β Cells

Frontiers in Endocrinology ◽

10.3389/fendo.2021.716692 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sugyeong Jo ◽

Sungsoon Fang

Keyword(s):

Clinical Trials ◽

T Cells ◽

Type Ii Diabetes ◽

Immune Modulation ◽

Therapeutic Strategies ◽

Immune Homeostasis ◽

Type I ◽

Type Ii ◽

Pancreatic Β Cell ◽

Β Cell

Increased incidence of type I and type II diabetes has been prevailed worldwide. Though the pathogenesis of molecular mechanisms remains still unclear, there are solid evidence that disturbed immune homeostasis leads to pancreatic β cell failure. Currently, autoimmunity and uncontrolled inflammatory signaling pathways have been considered the major factors in the pathogenesis of diabetes. Many components of immune system have been reported to implicate pancreatic β cell failure, including helper T cells, cytotoxic T cells, regulatory T cells and gut microbiota. Immune modulation of those components using small molecules and antibodies, and fecal microbiota transplantation are undergoing in many clinical trials for the treatment of type I and type II diabetes. In this review we will discuss the basis of molecular pathogenesis focusing on the disturbed immune homeostasis in type I and type II diabetes, leading to pancreatic β cell destruction. Finally, we will introduce current therapeutic strategies and clinical trials by modulation of immune system for the treatment of type I and type II diabetes patients.

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Structure-based mapping of the TβRI and TβRII receptor binding sites of the parasitic TGF-β mimic, Hp-TGM

10.1101/2020.12.08.416701 ◽

2020 ◽

Author(s):

Ananya Mukundan ◽

Chang-Hyeock Byeon ◽

Cynthia S. Hinck ◽

Danielle J. Smyth ◽

Rick M. Maizels ◽

...

Keyword(s):

T Cells ◽

Chemical Shift ◽

Solution Structure ◽

Adaptive Immune System ◽

Structural Similarity ◽

Binary Complex ◽

Type I ◽

Type Ii ◽

Nmr Chemical Shift ◽

Heligmosomoides Polygyrus

AbstractTGF-β is a secreted signaling protein involved in many physiological processes: organ development, production and maintenance of the extracellular matrix, as well as regulation of the adaptive immune system. As a cytokine, TGF-β stimulates the differentiation of CD4+ T-cells into regulatory T-cells (Tregs) that act to promote peripheral immune tolerance. The murine parasite Heligmosomoides polygyrus takes advantage of this pathway to induce inducing Foxp3+ Tregs in a similar manner using a TGF-β mimic (TGM), comprised of five tandem complement control protein (CCP) domains, designated D1-D5. Despite having no structural homology to TGF-β or to TGF-β family proteins, TGM binds directly to the TGF-β type I and type II receptors, TβRI and TβRII. To further investigate, NMR titration, and SPR and ITC binding experiments were performed, showing that TGM-D2, with the aid of D1, binds TβRI and TGM-D3 binds TβRII. Competition ITC experiments showed that TGM-D3 competes with TGF-β for binding to TβRII, consistent with TGM-D3-induced NMR chemical shift perturbations of TβRII which aligned with the solvent inaccessible areas of TβRII upon binding TGF-β. Thus, TGM-D3 binds to the same edged β-strand of TβRII that is used to bind TGF-β. Competition ITC experiments demonstrated that TGM-D1D2 and TGF-β3:TβRII compete for binding to TβRI, while TGM-D2-induced NMR chemical shift perturbation of TβRI showed that TGM-D2 binds to the same pre-helix extension of TβRI as does the TGF-β/TβRII binary complex. The solution structure of TGM-D3 revealed that while it has the overall structure of a CCP domain, TGM-D3 has an insertion in the hypervariable loop uncommon to CCP domains. These findings suggest that parasitic TGM, despite its lack of structural similarity to TGF-β, evolved to take advantage of the binding regions of the mammalian TGF-β type I and type II receptors. The structure of this TGM domain, along with the predicted structure of other H. polygyrus secreted proteins reported in the literature, suggest that TGM is part of a larger family of evolutionarily-adapted immunomodulatory CCP-containing proteins.

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High Expression of Ecto-Nucleotidases CD39 and CD73 in Human Endometrial Tumors

Mediators of Inflammation ◽

10.1155/2014/509027 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 30

Author(s):

Elisabet Aliagas ◽

August Vidal ◽

Laura Texidó ◽

Jordi Ponce ◽

Enric Condom ◽

...

Keyword(s):

Gene Expression ◽

Endometrial Cancer ◽

Genital Tract ◽

Female Genital Tract ◽

Tumor Grade ◽

Type I ◽

Type Ii ◽

Extracellular Adenosine ◽

Serous Tumors ◽

Female Genital

One of the strategies used by tumors to evade immunosurveillance is the accumulation of extracellular adenosine, which has immunosupressive and tumor promoting effects. The study of the mechanisms leading to adenosine formation at the tumor interstitium are therefore of great interest in oncology. The dominant pathway generating extracellular adenosine in tumors is the dephosphorylation of ATP by ecto-nucleotidases. Two of these enzymes acting sequentially, CD39 and CD73, efficiently hydrolyze extracellular ATP to adenosine. They have been found to play a crucial role in a variety of tumors, but there were no data concerning endometrial cancer, the most frequent of the invasive tumors of the female genital tract. The aim of the present work is to study the expression of CD39 and CD73 in human endometrial cancer. We have analyzed protein and gene expression, as well as enzyme activity, in type I endometrioid adenocarcinomas and type II serous adenocarcinomas and their nonpathological endometrial counterparts. High levels of both enzymes were found in tumor samples, with significantly increased expression of CD39 in type II serous tumors, which also coincided with the higher tumor grade. Our results reinforce the involvement of the adenosinergic system in cancer, emphasizing the relevance of ecto-nucleotidases as emerging therapeutic targets in oncology.

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