scholarly journals Extracellular CIRP decreases Siglec-G expression on B-1a cells skewing them towards a pro-inflammatory phenotype in sepsis

2021 ◽  
Vol 27 (1) ◽  
Author(s):  
William Royster ◽  
Hui Jin ◽  
Ping Wang ◽  
Monowar Aziz

Abstract Background Sepsis is a life-threatening disease syndrome caused by a dysregulated host response to infection and injury. Extracellular cold-inducible RNA-binding protein (eCIRP) acts as a damage-associated molecular pattern. Peritoneal cavity (PerC) B-1a cells attenuate inflammation and tissue injury by spontaneous releasing natural IgM and IL-10. Sialic acid-binding immunoglobulin-type lectin-G (Siglec-G) is a CD33-related receptor highly expressed in B-1a cells to serve critical immunoregulatory functions. In sepsis, B-1a cell numbers in PerC are decreased. We hypothesized that eCIRP causes the reduction of PerC B-1a cells and alters their function during sepsis. Methods Sepsis was induced in WT and CIRP−/− mice by cecal ligation and puncture (CLP). PerC washout cells were collected and B-1a cells and Siglec-G were assessed by flow cytometry. Mice were i.p. injected with recombinant murine (rm) CIRP and after 20 h, Siglec-G expression in PerC B-1a cells were assessed. PerC B-1a cells were treated with rmCIRP for 4 h and Siglec-G expression was assessed. PerC B-1a cells were pre-treated with anti-Siglec-G Ab and then after stimulated with rmCIRP for 24 h, IL-6 levels in the culture supernatants were assessed. Results eCIRP levels in the PerC were elevated in septic mice. In WT mice, the frequencies and numbers of total and Siglec-G+ B-1a cells in the PerC were significantly decreased in the CLP group compared to sham group, whereas in CIRP−/− mice, their frequencies and numbers in sepsis were significantly rescued compared to WT septic mice. Mice injected with rmCIRP showed decreased frequencies and numbers of total and Siglec-G+ PerC B-1a cells compared to PBS-injected mice. In vitro treatment of PerC B-1a cells with rmCIRP demonstrated significant reduction in Siglec-G mRNA and protein compared to PBS group. PerC B-1a cells treated with anti-Siglec-G Ab had significantly higher production of IL-6 in response to rmCIRP compared to IgG control. Anti-Siglec-G Ab treated B-1a cells co-cultured with macrophages produced significantly higher levels of IL-6, and TNF-α, and lower levels of IL-10 compared to IgG-treated B-1a cells and macrophage co-cultures stimulated with rmCIRP. Conclusion eCIRP reduces PerC B-1a cell pool and skews them to a pro-inflammatory phenotype by downregulating Siglec-G expression. Targeting eCIRP will retain Siglec-G expressing B-1a cells in the PerC and preserve their anti-inflammatory function in sepsis.

2022 ◽  
Vol 8 (1) ◽  
Author(s):  
Xiaoyan Wang ◽  
Danyong Liu ◽  
XiHe Zhang ◽  
LiuMing Yang ◽  
Zhengyuan Xia ◽  
...  

AbstractAcute lung injury (ALI) represents a frequent sepsis-induced inflammatory disorder. Mesenchymal stromal cells (MSCs) elicit anti-inflammatory effects in sepsis. This study investigated the mechanism of exosomes from adipose-derived MSCs (ADMSCs) in sepsis-induced ALI. The IL-27r−/− (WSX-1 knockout) or wild-type mouse model of sepsis was established by cecal ligation and puncture (CLP). The model mice and lipopolysaccharide (LPS)-induced macrophages were treated with ADMSC-exosomes. The content of Dil-labeled exosomes in pulmonary macrophages, macrophages CD68+ F4/80+ in whole lung tissues, and IL-27 content in macrophages were detected. The mRNA expression and protein level of IL27 subunits P28 and EBI3 in lung tissue and the levels of IL-6, TNF-α, and IL-1β were measured. The pulmonary edema, tissue injury, and pulmonary vascular leakage were measured. In vitro, macrophages internalized ADMSC-exosomes, and ADMSC-exosomes inhibited IL-27 secretion in LPS-induced macrophages. In vivo, IL-27 knockout attenuated CLP-induced ALI. ADMSC-exosomes suppressed macrophage aggregation in lung tissues and inhibited IL-27 secretion. ADMSC-exosomes decreased the contents of IL-6, TNF-α, and IL-1β, reduced pulmonary edema and pulmonary vascular leakage, and improved the survival rate of mice. Injection of recombinant IL-27 reversed the protective effect of ADMSC-exosomes on sepsis mice. Collectively, ADMSC-exosomes inhibited IL-27 secretion in macrophages and alleviated sepsis-induced ALI in mice.


2021 ◽  
Vol 12 ◽  
Author(s):  
Atsushi Murao ◽  
Chuyi Tan ◽  
Alok Jha ◽  
Ping Wang ◽  
Monowar Aziz

Extracellular cold-inducible RNA-binding protein (eCIRP) is an important damage-associated molecular pattern (DAMP). Despite our understanding of the potentially harmful effects of eCIRP in sepsis, how eCIRP is released from cells remains elusive. Exosomes are endosome-derived extracellular vesicles, which carry proteins, lipids, and nucleic acids to facilitate intercellular communication and several extracellular functions. We hypothesized that eCIRP is released via exosomes to induce inflammation in sepsis. Exosomes isolated from the supernatants of LPS-treated macrophage culture and serum of endotoxemia and polymicrobial sepsis mice showed high purity, as revealed by their unique median sizes ranging between 70 and 126 nm in diameter. eCIRP levels of the exosomes were significantly increased after LPS treatment in the supernatants of macrophage culture, mouse serum, and cecal ligation and puncture (CLP)-induced sepsis mouse serum. Protease protection assay demonstrated the majority of eCIRP was present on the surface of exosomes. Treatment of WT macrophages and mice with exosomes isolated from LPS-treated WT mice serum increased TNFα and IL-6 production. However, treatment with CIRP−/- mice serum exosomes significantly decreased these levels compared with WT exosome-treated conditions. CIRP−/- mice serum exosomes significantly decreased neutrophil migration in vitro compared with WT exosomes. Treatment of mice with serum exosomes isolated from CIRP−/- mice significantly reduced neutrophil infiltration into the peritoneal cavity. Our data suggest that eCIRP can be released via exosomes to induce cytokine production and neutrophil migration. Thus, exosomal eCIRP could be a potential target to inhibit inflammation.


2012 ◽  
Vol 303 (10) ◽  
pp. F1443-F1453 ◽  
Author(s):  
Chung-Hsi Hsing ◽  
Chiou-Feng Lin ◽  
Edmund So ◽  
Ding-Ping Sun ◽  
Tai-Chi Chen ◽  
...  

Bone morphogenetic protein (BMP)-7 protects sepsis-induced acute kidney injury (AKI). Dexmedetomidine (DEX), an α2-adrenoceptor (α2-AR) agonist, has anti-inflammatory effects. We investigated the protective effects of DEX on sepsis-induced AKI and the expression of BMP-7 and histone deacetylases (HDACs). In vitro , the effects of DEX or trichostatin A (TSA, an HDAC inhibitor) on TNF-α, monocyte chemotactic protein (MCP-1), BMP-7, and HDAC mRNA expression in LPS-stimulated rat renal tubular epithelial NRK52E cells, was determined using real-time PCR. In vivo, mice were intraperitoneally injected with DEX (25 μg/kg) or saline immediately and 12 h after cecal ligation and puncture (CLP) surgery. Twenty-four hours after CLP, we examined kidney injury and renal TNF-α, MCP-1, BMP-7, and HDAC expression. Survival was monitored for 120 h. LPS increased HDAC2, HDAC5, TNF-α, and MCP-1 expression, but decreased BMP-7 expression in NRK52E cells. DEX treatment decreased the HDAC2, HDAC5, TNF-α, and MCP-1 expression, but increased BMP-7 and acetyl histone H3 expression, whose effects were blocked by yohimbine, an α2-AR antagonist. With DEX treatment, the LPS-induced TNF-α expression and cell death were attenuated in scRNAi-NRK52E but not BMP-7 RNAi-NRK52E cells. In CLP mice, DEX treatment increased survival and attenuated AKI. The expression of HDAC2, HDAC5, TNF-α, and MCP-1 mRNA in the kidneys of CLP mice was increased, but BMP-7 was decreased. However, DEX treatment reduced those changes. DEX reduces sepsis-induced AKI by decreasing TNF-α and MCP-1 and increasing BMP-7, which is associated with decreasing HDAC2 and HDAC5, as well as increasing acetyl histone H3.


2020 ◽  
Vol 40 (12) ◽  
Author(s):  
Shunwan Jiang ◽  
Zhi Chen ◽  
Wenqiang Lai ◽  
Qingchun Mai ◽  
Dayu Chen ◽  
...  

Abstract Traditional Chinese medicine (TCM), such as Huanglian-Jie-Du-Tang, a heat-clearing and detoxifying decoction is beneficial for alleviation of inflammation-related diseases. The objective of the present study is to uncover the effect and mechanism of heat-clearing, detoxifying and blood stasis removing decoction (HDBD) on the treatment of acute soft tissue injury (STI) which is characterized with excessive inflammatory cascade at the onset. Male Sprague–Dawley (SD) rats with hammer beating served as the in vivo models of acute STI. Hematoxylin–Eosin (HE) staining was used for histopathology assessment. The levels of inflammatory factors, including prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1t and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA). Human dermal microvascular endothelium cell line HMEC-1 and rat vascular endothelium cell line RAOEC were used to explore the mechanism in vitro. Luciferase gene reporter assay was applied to determine the relationship between miR-26b-5p and Cyclo-oxygenase 2 (COX2). The results showed that HDBD intervention significantly reduced the temperature difference between the healthy side and affected side of rats with hammer beating, together with the decreased levels of COX2, PGE2, TNF-α, IL-6 and IL-1β, and the increased level of miR-26b-5p. In mechanism, miR-26b-5p targeted COX2 and decreased its expression, leading to significant decreases in the levels of PGE2, TNF-α and IL-6 in RAOEC and HMEC-1 cells. In addition, miR-26b-5p inhibition impaired the effects of HDBD on the suppression of PGE2, TNF-α, IL-6 and IL-1β in vitro. In conclusion, the present study revealed that HDBD relieved acute STI via modulating miR-26b-5p/COX2 axis to inhibit inflammation.


2021 ◽  
Vol 12 ◽  
Author(s):  
Siavash Bolourani ◽  
Ezgi Sari ◽  
Max Brenner ◽  
Ping Wang

Extracellular cold-inducible RNA-binding protein (eCIRP), a new damage-associated molecular pattern (DAMP), has been recently shown to play a critical role in promoting the development of bleomycin-induced pulmonary fibrosis. Although fibroblast activation is a critical component of the fibrotic process, the direct effects of eCIRP on fibroblasts have never been examined. We studied eCIRP’s role in the induction of inflammatory phenotype in pulmonary fibroblasts and its connection to bleomycin-induced pulmonary fibrosis in mice. We found that eCIRP causes the induction of proinflammatory cytokines and differentially expression-related pathways in a TLR4-dependent manner in pulmonary fibroblasts. Our analysis further showed that the accessory pathways MD2 and Myd88 are involved in the induction of inflammatory phenotype. In order to study the connection of the enrichment of these pathways in priming the microenvironment for pulmonary fibrosis, we investigated the gene expression profile of lung tissues from mice subjected to bleomycin-induced pulmonary fibrosis collected at various time points. We found that at day 14, which corresponds to the inflammatory-to-fibrotic transition phase after bleomycin injection, TLR4, MD2, and Myd88 were induced, and the transcriptome was differentially enriched for genes in those pathways. Furthermore, we also found that inflammatory cytokines gene expressions were induced, and the cellular responses to these inflammatory cytokines were differentially enriched on day 14. Overall, our results show that eCIRP induces inflammatory phenotype in pulmonary fibroblasts in a TLR4 dependent manner. This study sheds light on the mechanism by which eCIRP induced inflammatory fibroblasts, contributing to pulmonary fibrosis.


2020 ◽  
Author(s):  
Wandang Wang ◽  
Xuran Yang ◽  
Mingfa Guo ◽  
Zhifeng Pan ◽  
Mingjin Qiu ◽  
...  

Abstract Background: Neonatal sepsis is an acute life-threatening condition in neonates, and a proper innate inflammatory is essential for prevention of the systemic inflammation associated with sepsis. As the most potential antigen-presenting innate immune cells, dentritic cells (DCs) dysfunction has been verified detrimental for sepsis. B and T lymphocyte attenuator (BTLA) is an immune-regulatory receptor shown to be associated with DCs dysfunction. However, the role of BTLA expression in myeloid DCs (mDCs) in neonatal sepsis is unknown. Methods: 61 of neonates with sepsis and 32 of neonates having no suspicion of sepsis as control were enrolled into this study. BTLA and HLA-DR expression in mDCs was measured by flow cytometry. To further study the role of BTLA in regulating mDCs function, BTLA+mDCs and BTLA-mDCs from septic neonates were sorted and utilized to evaluate the phagacytosis capacity, bactericidal ability as well as cytokine secretion of mDCs.Results: A higher percentage of BTLA+mDCs were observed in neonatal septic patients and the percentage was positively correlated to the duration of hospitalization of neonates as well as the severity of sepsis. Moreover, a decrease MFI expression of HLA-DR was found in mDCs in neonatal sepsis, which expression was negatively correlated with the percentage of BTLA+mDCs. When compared to BTLA-mDCs, sorted BTLA+mDCs exhibited lower FITC-dextran uptake capacity but more CFU E.coli number after cells challenged by E.coli. In addition, BTLA+mDCs comparatively secreted lower level of TNF-α and IL-12, but higher IL-10. Conclusions: A higher level of BTLA in mDCs in the observed septic neonates was associated to the severity of neonatal sepsis; therefore, BTLA expression in mDCs could be a useful biomarker help to determine the neonatal sepsis development. Additionally, BTLA negatively regulated the phagocytosis capacity and bactericidal ability of mDCs and lowered their antigen-presenting ability as well as altered cells into an anti-inflammatory phenotype. Thus, targeting BTLA in mDCs may be a new therapeutic strategy for neonatal sepsis.


2020 ◽  
Vol 19 (4) ◽  
pp. 715-720
Author(s):  
XiaoBo Wang ◽  
JianHua Wu ◽  
BuKao Ni

Purpose: To investigate the protective effects of 4, 5-O-dicaffeoylquinic acid (DCQA) isolated from Xanthium sibiricum Patr. against mouse sepsis caused by cecal ligation/puncture (CLP) in vivo, as well as the molecular mechanisms of action involved.Methods: DCQA (7.5, 15, and 30 mg/kg/day) were administered to the mice with sepsis and the survival rate was obtained. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 were examined by enzyme-linked immunosorbent assay (ELISA). Subsequently, the lipopolysaccharide (LPS) neutralizing ability of DCQA (2, 4, and 8 μg/mL) was measured using limulus amebocyte lysate (LAL) test in vitro. Furthermore, the effect of DCQA (10, 20, and 40 μg/mL) on mRNA expression of TNF-α, IL-6, and IL-8 in LPS (100 ng/mL)-treated RAW 264.7 cells was assessed using quantitative real time-polymerase chain reaction (RT-qPCR) assay.Results: DCQA significantly improved the survival rate of mice with sepsis caused by CLP (35, 50, and 65 %, respectively vs. 15 % for control, p < 0.05). LPS levels fell on co-incubation with DCQA in vitro. Moreover, ELISA and RT-qPCR results revealed that DCQA treatment lowered tendency in the mRNA expression of TNF-α, IL-6, and IL-8 (p < 0.01).Conclusion: DCQA exhibits protective effects against sepsis in mice mediated by downregulating TNF-α, IL-6, and IL-8. Further studies, in animals and humans are requied to determine the safety and efficacy of DCQA in both animal and clinical management of sepsis. Keywords: Xanthium sibiricum, 4,5-O-Dicaffeoylquinic acid, Sepsis, Cecal ligation and puncture, Lipopolysaccharide, TNF-α, IL-6, IL-8


2020 ◽  
Author(s):  
Namdar Ahmadabad Hasan ◽  
reza shafiei ◽  
Hatam Gholam Reza ◽  
Zolfaghari Emameh Reza ◽  
Aspatwar Ashok

Abstract Background The Fucose-Mannose Ligand (FML) of Leishmania infantum is a complex glycoprotein which does not elicit adequate immunogenicity in human. In recent years, adjuvant compounds derived from plants have been used for improving the immunogenicity of the vaccines. Glycyrrhizin (GL) is a natural triterpenoid saponin that has known immunomodulatory activities. In the present study, we investigated the effects of a co-treatment with FML and GL on the production of cytokines and nitric oxide ( NO) by macrophages, in vitro . Methods Lipopolysaccharide (LPS) stimulated murine peritoneal macrophages were treated with FML (5 μg/ml) of Leishmania infantum and various concentrations of GL (1 μg/ml, or 10 μg/ml or 20 μg/ml). After 48h of treatment, cell culture supernatants were recovered and the levels of TNF-α, IL-10, IL-12p70, and IP-10 were measured by sandwich ELISA and NO concentration by Griess reaction. Results Our results indicated that the treatment of activated macrophages with FML plus GL leads to enhanced production of NO, TNF-α, IL-12p70, and reduction of IL-10 levels in comparison with FML treatment alone. Conclusions We, therefore, concluded that GL can improve the immunostimulatory effect of FML on macrophages and leads to polarization of them toward an M1-like phenotype.


2021 ◽  
Vol 12 ◽  
Author(s):  
Daniela C. Ivan ◽  
Sabrina Walthert ◽  
Giuseppe Locatelli

In multiple sclerosis (MS) and other neuroinflammatory diseases, monocyte-derived cells (MoCs) traffic through distinct central nervous system (CNS) barriers and gain access to the organ parenchyma exerting detrimental or beneficial functions. How and where these MoCs acquire their different functional commitments during CNS invasion remains however unclear, thus hindering the design of MS treatments specifically blocking detrimental MoC actions. To clarify this issue, we investigated the distribution of iNOS+ pro-inflammatory and arginase-1+ anti-inflammatory MoCs at the distinct border regions of the CNS in a mouse model of MS. Interestingly, MoCs within perivascular parenchymal spaces displayed a predominant pro-inflammatory phenotype compared to MoCs accumulating at the leptomeninges and at the intraventricular choroid plexus (ChP). Furthermore, in an in vitro model, we could observe the general ability of functionally-polarized MoCs to migrate through the ChP epithelial barrier, together indicating the ChP as a potential CNS entry and polarization site for MoCs. Thus, pro- and anti-inflammatory MoCs differentially accumulate at distinct CNS barriers before reaching the parenchyma, but the mechanism for their phenotype acquisition remains undefined. Shedding light on this process, we observed that endothelial (BBB) and epithelial (ChP) CNS barrier cells can directly regulate transcription of Nos2 (coding for iNOS) and Arg1 (coding for arginase-1) in interacting MoCs. More specifically, while TNF-α+IFN-γ stimulated BBB cells induced Nos2 expression in MoCs, IL-1β driven activation of endothelial BBB cells led to a significant upregulation of Arg1 in MoCs. Supporting this latter finding, less pro-inflammatory MoCs could be found nearby IL1R1+ vessels in the mouse spinal cord upon neuroinflammation. Taken together, our data indicate differential distribution of pro- and anti-inflammatory MoCs at CNS borders and highlight how the interaction of MoCs with CNS barriers can significantly affect the functional activation of these CNS-invading MoCs during autoimmune inflammation.


2018 ◽  
Vol 38 (2) ◽  
Author(s):  
Yulong Yao ◽  
Fangyuan Sun ◽  
Ming Lei

To investigate the regulatory mechanism of miR-25 in sepsis-induced cardiomyocyte apoptosis. Rats models of sepsis were established by cecal ligation and puncture (CLP). Lipopolysaccharide (LPS)-induced cardiomyocyte was used as an in vitro model of sepsis. The expressions of miR-25, tensin homolog deleted on chromosome 10 (PTEN), Toll-like receptors 4 (TLR4), and p-p65 were analyzed by quantitative real-time PCR (qRT-PCR) and Western blot, respectively. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by ELISA. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated d-UTP nick end labeling (TUNEL) assay. The relationship between miR-25 and PTEN was measured by luciferase reporter assays. MiR-25 expression in serum of CLP rats and LPS-induced cardiomyocyte was decreased, while the contents of TNF-α and IL-6 were increased. Moreover, the expressions of PTEN, TLR4, and p-p65 in LPS-induced cardiomyocyte were significantly increased. Overexpression of miR-25 increased the survival rate of rats, inhibited LPS-increased cardiomyocyte apoptosis, reversed the increased expression of PTEN, TLR4, p-p65, TNF-α, and IL-6 induced by LPS. The luciferase assay demonstrated that PTEN was a target of miR-25. Additionally, pcDNA-PTEN reversed the inhibitory effect of miR-25 mimic on cardiomyocyte apoptosis, while TAK-242 (TLR-4 inhibitor) countered this effect. miR-25 reduced LPS-induced cardiomyocyte apoptosis by down-regulating PTEN/TLR4/NF-κB axis.


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