scholarly journals Doxycycline Protects Thymic Epithelial Cells from Mitomycin C-Mediated Apoptosis In Vitro via Trx2-NF-κB-Bcl-2/Bax Axis

2016 ◽  
Vol 38 (2) ◽  
pp. 449-460 ◽  
Author(s):  
Jun Wang ◽  
Ya Zhuo ◽  
Lei Yin ◽  
Hui Wang ◽  
Yanqiu Jiang ◽  
...  
Keyword(s):  
T Cell ◽  
Epithelial Cells ◽  
Mitomycin C ◽  
Mapk Signaling ◽  
Thymic Epithelial Cells ◽  
Cell Repertoire ◽  
Gm Csf ◽  
Induced Apoptosis ◽  
A Tec

Background/Aims: Age-associated and stress-induced involution of the thymus is accompanied by reduced numbers of thymic epithelial cells (TECs) and severe reduction in peripheral T cell repertoire specificities. These events seriously affect immune function, but the mechanisms involved are unclear. Our preliminary findings showed that doxycycline (Dox) could drive the proliferation of a TEC line (MTEC1 cells) partially via the MAPK signaling pathway. Dox can also up-regulate IL-6 and GM-CSF expression via the NF-κB and MAPK/ERK pathways. Herein, we investigate the effects and mechanisms used by Dox that protect against mitomycin C (MMC)-induced MTEC1 cell apoptosis. Methods: MTEC1 cells were treated with Dox, MMC, and Dox plus MMC for different amounts of time. The expression of Trx2, NF-κB, Bcl-2, and Bax proteins were then detected by western blotting. Results: Our findings show that Dox protects MTEC1 cells from MMC-induced apoptosis. Dox up-regulated the expression of Trx2 and promoted NF-κB phosphorylation. Meanwhile, Dox also increased the expression of Bcl-2, partially reduced the expression of Bax, and normalized the ratio of Bcl-2 to Bax. Conclusion: Dox exerts an anti-apoptosis function via the NF-κB-Bcl-2/Bax and Trx2-ASK1/JNK pathways in vitro. Therefore, Dox may represent a drug that could be used to attenuate thymic senescence, rescue thymic function, and promote T cell reconstitution.

scholarly journals p-Coumaric Acid Protects Human Lens Epithelial Cells against Oxidative Stress-Induced Apoptosis by MAPK Signaling

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Jiao Peng ◽  
Ting-ting Zheng ◽  
Yue Liang ◽  
Li-fang Duan ◽  
Yao-dong Zhang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Epithelial Cells ◽  
Mapk Signaling ◽  
Human Lens ◽  
Lens Epithelial Cells ◽  
Dependent Manner ◽  
Coumaric Acid ◽  
Underlying Mechanisms ◽  
Induced Apoptosis

To protect against oxidative stress-induced apoptosis in lens epithelial cells is a potential strategy in preventing cataract formation. The present study aimed at studying the protective effect and underlying mechanisms of p-coumaric acid (p-CA) on hydrogen peroxide- (H2O2-) induced apoptosis in human lens epithelial (HLE) cells (SRA 01–04). Cells were pretreated with p-CA at a concentration of 3, 10, and 30 μM before the treatment of H2O2 (275 μM). Results showed that pretreatment with p-CA significantly protected against H2O2-induced cell death in a dose-dependent manner, as well as downregulating the expressions of both cleaved caspase-3 and cleaved caspase-9 in HLE cells. Moreover, p-CA also greatly suppressed H2O2-induced intracellular ROS production and mitochondrial membrane potential loss and elevated the activities of T-SOD, CAT, and GSH-Px of H2O2-treated cells. As well, in vitro study showed that p-CA also suppressed H2O2-induced phosphorylation of p-38, ERK, and JNK in HLE cells. These findings demonstrate that p-CA suppresses H2O2-induced HLE cell apoptosis through modulating MAPK signaling pathways and suggest that p-CA has a potential therapeutic role in the prevention of cataract.

scholarly journals TCR+CD4−CD8− (double negative) T cells protect from cisplatin-induced renal epithelial cell apoptosis and acute kidney injury

2020 ◽  
Vol 318 (6) ◽  
pp. F1500-F1512
Author(s):  
Jing Gong ◽  
Sanjeev Noel ◽  
Joshua Hsu ◽  
Errol L. Bush ◽  
Lois J. Arend ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Epithelial Cells ◽  
Kidney Injury ◽  
Double Negative ◽  
Tubular Epithelial Cells ◽  
Proximal Tubular Epithelial Cells ◽  
Proximal Tubular ◽  
Induced Apoptosis

Acute kidney injury (AKI) due to cisplatin is a significant problem that limits its use as an effective chemotherapeutic agent. T cell receptor+CD4−CD8− double negative (DN) T cells constitute the major T cell population in the human and mouse kidney, express programmed cell death protein (PD)-1, and protect from ischemic AKI. However, the pathophysiological roles of DN T cells in cisplatin-induced AKI is unknown. In this study, wild-type mice were treated with cisplatin (30 mg/kg) or vehicle, and the effects on kidney DN T cell numbers and function were measured. In vitro experiments evaluated effects of kidney DN T cells on cisplatin-induced apoptosis and PD ligand 1 (PD-L1) in renal epithelial cells. Adoptive transfer experiments assessed the therapeutic potential of DN T cells during cisplatin-induced AKI. Our results show that kidney DN T cell population increased at 24 h and declined by 72 h after cisplatin treatment. Cisplatin treatment increased kidney DN T cell proliferation, apoptosis, CD69, and IL-10 expression, whereas CD62L, CD44, IL-17A, interferon-γ, and TNF-α were downregulated. Cisplatin treatment decreased both PD-1 and natural killer 1.1 subsets of kidney DN T cells with a pronounced effect on the PD-1 subset. In vitro kidney DN T cell coculture decreased cisplatin-induced apoptosis in kidney proximal tubular epithelial cells, increased Bcl-2, and decreased cleaved caspase 3 expression. Cisplatin-induced expression of PD ligand 1 was reduced in proximal tubular epithelial cells cocultured with DN T cells. Adoptive transfer of DN T cells attenuated kidney dysfunction and structural damage from cisplatin-induced AKI. These results demonstrate that kidney DN T cells respond rapidly and play a protective role during cisplatin-induced AKI.

scholarly journals The Aire family expands

2019 ◽  
Vol 216 (5) ◽  
pp. 1010-1011
Author(s):  
Adrian Liston ◽  
James Dooley
Keyword(s):  
T Cell ◽  
Epithelial Cells ◽  
Lymph Nodes ◽  
Thymic Epithelial Cells ◽  
T Cell Tolerance ◽  
T Cell Repertoire ◽  
Cell Tolerance ◽  
Cell Repertoire

T cell tolerance depends upon Aire-expressing cells to purge the T cell repertoire of autoreactive clones. Once thought to be the exclusive domain of thymic epithelial cells, a new study by Yamano et al. (https://doi.org/10.1084/jem.20181430) in this issue of JEM identifies ILC3-like cells in the lymph nodes with similar properties.

Shaping of the autoreactive T-cell repertoire by a splice variant of self protein expressed in thymic epithelial cells

10.1038/71540 ◽  
2000 ◽  
Vol 6 (1) ◽  
pp. 56-61 ◽  
Author(s):  
Ludger Klein ◽  
Matthias Klugmann ◽  
Klaus-Armin Nave ◽  
V K Tuohy ◽  
Bruno Kyewski
Keyword(s):  
T Cell ◽  
Epithelial Cells ◽  
Splice Variant ◽  
Thymic Epithelial Cells ◽  
T Cell Repertoire ◽  
Cell Repertoire ◽  
Autoreactive T Cell

scholarly journals An in vitro system of T cell maturation-effect of cytokines and of thymic epithelial cells ♦ 865

1998 ◽  
Vol 43 ◽  
pp. 150-150
Author(s):  
Athena P Kourtis ◽  
Francis K Lee ◽  
Christian Ibegbu ◽  
Edmund Waller ◽  
Andre J Nahmias
Keyword(s):  
T Cell ◽  
Epithelial Cells ◽  
Cell Maturation ◽  
Thymic Epithelial Cells ◽  
In Vitro System ◽  
T Cell Maturation

scholarly journals MicroRNA-182-5p protects human lens epithelial cells against oxidative stress-induced apoptosis by inhibiting NOX4 and p38 MAPK signalling

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Zhao-Na Li ◽  
Ming-Xu Ge ◽  
Zhong-Fang Yuan
Keyword(s):  
Epithelial Cells ◽  
P38 Mapk ◽  
Mapk Signaling ◽  
Luciferase Reporter ◽  
Human Lens ◽  
Lens Epithelial Cells ◽  
Luciferase Reporter Gene ◽  
Age Related ◽  
Induced Apoptosis

Abstract Background MicroRNAs (miRNAs) are abnormally expressed in various ocular diseases, including age-related cataract. However, the role of miR-182-5p in the progression of age-related cataract remains unclear. Methods The expression of miR-182-5p in HLE-B3 cells was detected by qRT-PCR. HLE-B3 cells were transfected with miR-182-5p mimics. CCK-8, EdU, flow cytometry, 2′,7′-dichlorodihydrofluorescein diacetate, JC-1 kit, and western blot were used to assess the cell viability, proliferation, apoptosis, reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP), and protein expression, respectively, in vitro. The relationship between miR-182-5p and NOX4 was confirmed using the dual-luciferase reporter gene analysis. Results We found that miR-182-5p expression was significantly decreased by the H2O2 exposure. Overexpression of miR-182-5p promoted cell proliferation and inhibited ROS production and apoptosis in H2O2-induced HLE-B3 cells. Moreover, p-p-38, p-ERK, and p-JNK were up-regulated in H2O2-treated HLE-B3 cells, and overexpression of miR-182-5p reversed the effects of H2O2 on HLE-B3 cells. In addition, dual-luciferase reporter assay substantiated that NOX4 was a direct target and downregulated by miR-182-5p. Conclusions We concluded that miR-182-5p inhibited lens epithelial cells apoptosis through regulating NOX4 and p38 MAPK signaling, providing a novel biomarker for treatment of age-related cataract.

scholarly journals MicroRNA-182-5p protects human lens epithelial cells against oxidative stress-induced apoptosis by inhibiting NOX4 and p38 MAPK signalling

2020 ◽  
Author(s):  
Zhao-Na Li ◽  
Ming-Xu Ge ◽  
Zhong-Fang Yuan
Keyword(s):  
Epithelial Cells ◽  
P38 Mapk ◽  
Mapk Signaling ◽  
Luciferase Reporter ◽  
Human Lens ◽  
Lens Epithelial Cells ◽  
Luciferase Reporter Gene ◽  
Age Related ◽  
Induced Apoptosis

Abstract Background: MicroRNAs (miRNAs) are abnormally expressed in various ocular diseases, including age-related cataract. However, the role of miR-182-5p in the progression of age-related cataract remains unclear.Methods: The expression of miR-182-5p in HLE-B3 cells was detected by qRT-PCR. HLE-B3 cells were transfected with miR-182-5p mimics. CCK-8, EdU, flow cytometry, 2',7'-dichlorodihydrofluorescein diacetate, JC-1 kit, and western blot were used to assess the cell viability, proliferation, apoptosis, reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP), and protein expression, respectively, in vitro. The relationship between miR-182-5p and NOX4 was confirmed using the dual-luciferase reporter gene analysis.Results: We found that miR-182-5p expression was significantly decreased by the H2O2 exposure. Overexpression of miR-182-5p promoted cell proliferation and inhibited ROS production and apoptosis in H2O2-induced HLE-B3 cells. Moreover, p-p-38, p-ERK, and p-JNK were up-regulated in H2O2-treated HLE-B3 cells, and overexpression of miR-182-5p reversed the effects of H2O2 on HLE-B3 cells. In addition, dual-luciferase reporter assay substantiated that NOX4 was a direct target and downregulated by miR-182-5p.Conclusions: We concluded that miR-182-5p inhibited lens epithelial cells apoptosis through regulating NOX4 and p38 MAPK signaling, providing a novel biomarker for treatment of age-related cataract.

scholarly journals Self-mediated positive selection of T cells sets an obstacle to the recognition of nonself

2021 ◽  
Vol 118 (37) ◽  
pp. e2100542118
Author(s):  
Balázs Koncz ◽  
Gergő M. Balogh ◽  
Benjamin T. Papp ◽  
Leó Asztalos ◽  
Lajos Kemény ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Epithelial Cells ◽  
Positive Selection ◽  
Thymic Epithelial Cells ◽  
Immune Recognition ◽  
T Cell Repertoire ◽  
Cell Repertoire ◽  
Adaptive Immune ◽  
Selection Of

Adaptive immune recognition is mediated by the binding of peptide–human leukocyte antigen complexes by T cells. Positive selection of T cells in the thymus is a fundamental step in the generation of a responding T cell repertoire: only those T cells survive that recognize human peptides presented on the surface of cortical thymic epithelial cells. We propose that while this step is essential for optimal immune function, the process results in a defective T cell repertoire because it is mediated by self-peptides. To test our hypothesis, we focused on amino acid motifs of peptides in contact with T cell receptors. We found that motifs rarely or not found in the human proteome are unlikely to be recognized by the immune system just like the ones that are not expressed in cortical thymic epithelial cells or not presented on their surface. Peptides carrying such motifs were especially dissimilar to human proteins. Importantly, we present our main findings on two independent T cell activation datasets and directly demonstrate the absence of naïve T cells in the repertoire of healthy individuals. We also show that T cell cross-reactivity is unable to compensate for the absence of positively selected T cells. Additionally, we show that the proposed mechanism could influence the risk for different infectious diseases. In sum, our results suggest a side effect of T cell positive selection, which could explain the nonresponsiveness to many nonself peptides and could improve the understanding of adaptive immune recognition.

scholarly journals NF‐κB‐inducing kinase contributes to normal development of cortical thymic epithelial cells: its possible role in shaping a proper T‐cell repertoire

Immunology ◽  
2020 ◽  
Vol 160 (2) ◽  
pp. 198-208
Author(s):  
Koji Eshima ◽  
Kana Misawa ◽  
Chihiro Ohashi ◽  
Haruka Noma ◽  
Kazuya Iwabuchi
Keyword(s):  
T Cell ◽  
Epithelial Cells ◽  
Normal Development ◽  
Thymic Epithelial Cells ◽  
T Cell Repertoire ◽  
Cell Repertoire
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