scholarly journals Modulation of IGF2 Expression in the Murine Thymus and Thymic Epithelial Cells Following Coxsackievirus-B4 Infection

2021 ◽  
Vol 9 (2) ◽  
pp. 402
Author(s):  
Hélène Michaux ◽  
Aymen Halouani ◽  
Charlotte Trussart ◽  
Chantal Renard ◽  
Hela Jaïdane ◽  
...  

Coxsackievirus B4 (CV-B4) can infect human and murine thymic epithelial cells (TECs). In a murine TEC cell line, CV-B4 can downregulate the transcription of the insulin-like growth factor 2 (Igf2) gene coding for the self-peptide of the insulin family. In this study, we show that CV-B4 infections of a murine TEC cell line decreased Igf2 P3 promoter activity by targeting a region near the transcription start site; however, the stability of Igf2 transcripts remained unchanged, indicating a regulation of Igf2 transcription. Furthermore, CV-B4 infections decreased STAT3 phosphorylation in vitro. We also showed that mice infected with CV-B4 had an altered expression of Igf2 isoforms as detected in TECs, followed by a decrease in the pro-IGF2 precursor in the thymus. Our study sheds new light on the intrathymic regulation of Igf2 transcription during CV-B4 infections and supports the hypothesis that a viral infection can disrupt central self-tolerance to insulin by decreasing Igf2 transcription in the thymic epithelium.

2020 ◽  
Author(s):  
Hélène Michaux ◽  
Aymen Halouani ◽  
Charlotte Trussart ◽  
Chantal Renard ◽  
Hela Jaïdane ◽  
...  

ABSTRACTEpidemiological studies have evidenced a link between type 1 diabetes (T1D) and infections by enteroviruses, especially with coxsackievirus B4 (CV-B4). CV-B4 is able to infect human and murine thymic epithelial cells (TECs) and, in a murine TEC line, we have shown that the diabetogenic strain CV-B4 E2 decreases transcription of insulin-like growth factor 2 gene (Igf2), coding for the self-peptide of the insulin family. Here we show that in CV-B4 infection of mice alters Igf2 transcripts isoforms in TECs, followed by a decrease of pro-IGF2 precursor in the thymus. CV-B4 infection of a murine TEC line decreases Igf2 P3 promoter activity by targeting the region −68 to −22 upstream of the transcription start site (TSS) whereas Igf2 transcripts stability is not affected, pointing towards a regulation of Igf2 transcription. Our data also show that CV-B4 decreases IL-6/STAT3 signaling in vitro. This study provides new knowledge about the regulation of intrathymic Igf2 transcription by CV-B4 and reinforces the hypothesis that CV-B4 infection of the thymus could break central self-tolerance of the insulin family by decreasing Igf2 transcription and IGF2 presentation in thymus epithelium.IMPORTANCECoxsackievirus B4 represents one of the most important environmental factors associated to type 1 diabetes, autoimmune disease for which no curative treatment exist. The diabetogenic strain Coxsackievirus B4 E2 was previously shown to decrease Igf2 expression, important player for central tolerance towards insulin, in a thymic epithelial cell line. The understanding of Igf2 regulation mechanisms during coxsackievirus B4 infection represents an interest for the understanding of central tolerance development but also for Igf2 transcriptional regulation itself, still poorly understood.Here we demonstrate that, some transcripts isoforms of Igf2 are also decreased in thymic epithelial cells in vivo. Moreover, we show that this decrease is induced by an alteration of specific regions of Igf2 P3 promoter and may be linked by a decrease of STAT3 signaling. In fine we hope that this work could lead to future therapies leading to reprogramming central tolerance towards β cells antigens via Igf2 expression.


2000 ◽  
Vol 111 (1) ◽  
pp. 363-370 ◽  
Author(s):  
Katsuto Takenaka ◽  
Mine Harada ◽  
Tomoaki Fujisaki ◽  
Koji Nagafuji ◽  
Shinichi Mizuno ◽  
...  

2021 ◽  
Vol 9 (6) ◽  
pp. 1177
Author(s):  
Abdulaziz Alhazmi ◽  
Magloire Pandoua Nekoua ◽  
Hélène Michaux ◽  
Famara Sane ◽  
Aymen Halouani ◽  
...  

The thymus gland is a primary lymphoid organ for T-cell development. Various viral infections can result in disturbance of thymic functions. Medullary thymic epithelial cells (mTECs) are important for the negative selection of self-reactive T-cells to ensure central tolerance. Insulin-like growth factor 2 (IGF2) is the dominant self-peptide of the insulin family expressed in mTECs and plays a crucial role in the intra-thymic programing of central tolerance to insulin-secreting islet β-cells. Coxsackievirus B4 (CVB4) can infect and persist in the thymus of humans and mice, thus hampering the T-cell maturation and differentiation process. The modulation of IGF2 expression and protein synthesis during a CVB4 infection has been observed in vitro and in vivo in mouse models. The effect of CVB4 infections on human and mouse fetal thymus has been studied in vitro. Moreover, following the inoculation of CVB4 in pregnant mice, the thymic function in the fetus and offspring was disturbed. A defect in the intra-thymic expression of self-peptides by mTECs may be triggered by CVB4. The effects of viral infections, especially CVB4 infection, on thymic cells and functions and their possible role in the pathogenesis of type 1 diabetes (T1D) are presented.


2011 ◽  
Vol 301 (4) ◽  
pp. F793-F801 ◽  
Author(s):  
Abolfazl Zarjou ◽  
Shanzhong Yang ◽  
Edward Abraham ◽  
Anupam Agarwal ◽  
Gang Liu

Renal fibrosis is a final stage of many forms of kidney disease and leads to impairment of kidney function. The molecular pathogenesis of renal fibrosis is currently not well-understood. microRNAs (miRNAs) are important players in initiation and progression of many pathologic processes including diabetes, cancer, and cardiovascular disease. However, the role of miRNAs in kidney injury and repair is not well-characterized. In the present study, we found a unique miRNA signature associated with unilateral ureteral obstruction (UUO)-induced renal fibrosis. We found altered expression in UUO kidneys of miRNAs that have been shown to be responsive to stimulation by transforming growth factor (TGF)-β1 or TNF-α. Among these miRNAs, miR-21 demonstrated the greatest increase in UUO kidneys. The enhanced expression of miR-21 was located mainly in distal tubular epithelial cells. miR-21 expression was upregulated in response to treatment with TGF-β1 or TNF-α in human renal tubular epithelial cells in vitro. Furthermore, we found that blocking miR-21 in vivo attenuated UUO-induced renal fibrosis, presumably through diminishing the expression of profibrotic proteins and reducing infiltration of inflammatory macrophages in UUO kidneys. Our data suggest that targeting specific miRNAs could be a novel therapeutic approach to treat renal fibrosis.


2003 ◽  
Vol 77 (6) ◽  
pp. 358-364 ◽  
Author(s):  
Kai Riecke ◽  
André Schmidt ◽  
Ralf Stahlmann

1986 ◽  
Vol 83 (17) ◽  
pp. 6588-6592 ◽  
Author(s):  
K. H. Singer ◽  
L. S. Wolf ◽  
D. F. Lobach ◽  
S. M. Denning ◽  
D. T. Tuck ◽  
...  

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A925-A925
Author(s):  
Alessandra Romano ◽  
Nunziatina Parrinello ◽  
Sara Marino ◽  
Enrico La Spina ◽  
Massimo Fantini ◽  
...  

BackgroundNEO-201 is an IgG1 mAb targeting variants of CEACAM5/6 and has demonstrated tumor sensitivity and specificity in epithelial cells. Functional analysis has revealed that NEO-201 can engage innate immune effector mechanisms including ADCC and CDC to directly kill tumor cells expressing its target. A recent Phase 1 clinical trial at the NCI has determined both safety and recommended Phase 2 dosing. We have also seen the expression of the NEO-201 target on hematologic cells, specifically Tregs and neutrophils. Due to epitope being expressed both on malignant epithelial cells as well as several hematologic cells, we designed this study to explore the reactivity of NEO-201 against hematological neoplastic cells in vitro.MethodsPhenotypic analysis was conducted by flow cytometry. Cell lines used were six AML (HL60, U937, MOLM13, AML2, IMS-M2 and OCL-AML3), two multiple myelomas (MM) (OPM2, MM1.S), two acute lymphoblastic leukemia (ALL) (SUP-B15, RPMI8402) and four mantle cell lymphoma (MCL) (Jeko-1, Z138, JVM2 and JVM13). Markers used for flow cytometry analysis were CD15, CD45, CD38, CD138, CD14, CD19 and NEO-201. Functional analysis was performed by evaluating the ability of NEO-201 to mediate ADCC activity against AML cell lines using human NK cells as effector cells.Results5 of 6 AML cell lines tested bind to NEO-201 and the% of positive cells were 47%, 99.5%,100%,100% and 97.8% for HL60, U937, MOLM13, AML3 and IMS-M2, respectively. The% of positive cells in the two MM cell line were 99% and 18% for OPM2 and MM1.S, respectively. NEO-201 binding was not detected in the two ALL and the four MCL cell lines tested. Functional analysis has demonstrated that NEO-201 can mediate ADCC activity against the AML cell line (HL60) tested.ConclusionsThis study demonstrates that NEO-201 mAb’s target is expressed in most of the AML cell lines tested in vitro. In addition, we have shown it can mediate ADCC activity against HL60 cells (AML). Together, these findings provide a rationale for further investigation of the role of NEO-201 in AML as well as MM, further exploring patient PBMCs and bone marrow samples.


2021 ◽  
Vol 11 (6) ◽  
pp. 1129-1137
Author(s):  
Yuanyuan Liu ◽  
Chao He ◽  
Xin Li ◽  
Zewen Zhang ◽  
Ju Liu ◽  
...  

The epithelial-mesenchymal transition (EMT) of bronchial epithelial cells is a critical mechanism involved in transforming growth factor beta 1 (TGF-β1) induced asthma airway remodeling. Previous study has shown that interleukin 27 (IL-27) attenuates EMT in alveolar epithelial cells, but its effects on the BEAS-2B human bronchial epithelial cell line EMT remain unknown. Herein, we explored the effects of IL-27 on BEAS-2B EMT in vivo and in vitro. In the in vivo experiments, we found that IL-27 nose-drip therapy alleviated airway remodeling, increased the epithelial phenotypic marker epithelial-cadherin (E-cadherin), and decreased the mesenchymal phenotypic marker alpha-smooth muscle actin (α-SMA) compared with the asthmatic control group. We also found that IL-27 suppressed the signal transducer and activator of transcription (STAT3) in the lung tissue of asthmatic mice. in vitro, TGF-β1-induced EMT changes, including downregulation of E-cadherin and upregulation of α-SMA, were suppressed by IL-27 treatment. Additionally, STAT3 phosphorylation was activated by TGF-β1, whereas IL-27 inhibited the activation of TGF-β1 induced STAT3 phosphorylation. Our findings indicated that IL-27 could inhibit airway remodeling by attenuating bronchial epithelial cell EMT in vivo and in vitro. Therefore, IL-27 may be a beneficial therapeutic option targeting asthmatic airway remodeling.


1994 ◽  
Vol 266 (6) ◽  
pp. L612-L619 ◽  
Author(s):  
R. B. Devlin ◽  
K. P. McKinnon ◽  
T. Noah ◽  
S. Becker ◽  
H. S. Koren

Acute exposure of animals and humans to ozone results in decrements in lung function, development of airway hyperreactivity, inflammation, edema, damage to pulmonary cells, and production of several compounds with tissue damaging, fibrinogenic or fibrotic potential. The contribution of airway epithelial cells and alveolar macrophages to these processes is unclear. In this study we have directly exposed human alveolar macrophages and human airway epithelial cells to ozone in vitro and measured the cytotoxic effects of ozone, as well as the production of the inflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8), and fibronectin, all of which are substantially elevated in the bronchoalveolar lavage fluid of humans exposed to ozone. Cells were grown on rigid, collagen-impregnated filter supports, and the interaction of cells with ozone facilitated by exposing them to the gas with medium below the support but no medium on top of the cells. The results show that, although macrophages are much more sensitive to ozone than epithelial cells, they do not produce increased amounts of IL-6, IL-8, or fibronectin following ozone exposure. In contrast, epithelial cells produce substantially more of all three proteins following ozone exposure, and both IL-6 and fibronectin are secreted vectorially. An immortalized human airway epithelial cell line (BEAS 2B) was used in these experiments since human airway epithelial cells are infrequently available for in vitro studies. Data from this study extend previous findings which suggest that the BEAS cell line is a useful model to study the interaction between airway epithelial cells and environmental toxicants.


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