Molecular mechanism of TLR4 mediated T cell immune effect in transfusion-induced acute lung injury based on Slit2/Robo4 signaling pathway

2020 ◽  
Vol 13 ◽  
Author(s):  
Kun Xiao ◽  
Fei Zhao ◽  
WenJie Xie ◽  
Jian Ding ◽  
XiaoAn Gong ◽  
...  

Objective: To explore and investigate the molecular mechanism of TLR4 mediated T cell immune effect in transfusion-induced acute injury based on SLIT2/ROBO4 signaling pathway. Methods: Sixty C57/BL6 male mice (Wild type, WT) aged 8 to 10 weeks were randomly divided into 5 groups: 1) normal type WT, 2) LPS control group of WT type lipopolysaccharide, 3) WT type TRALI group (LPS + MHC-I mAb), 4) (TLR4 antibody) lipopolysaccharide LPS control group, 5) (TLR4 antibody) TRALI group (LPS + MHC-I mAb). Mice were dosed with LPS (0.1 mg / kg), and MHC-I mAb (2 mg / kg) was injected into the tail vein 24 hours later for modeling. After 2 hours, mice were sacrificed and experimental samples were collected. HE staining was performed to detect pathological features. The myeloperoxidase (MPO) activity and the level of IL-2, IL-6, TNF, IFN-γ, IL-17A as well as IL-10 were measured in the lung tissue homogenate supernatant. Blood, spleen single cell suspension and bronchoalveolar lavage fluid (BALF) were collected to detect the ratio of Treg and Th17 cells by flow cytometry, respectively. RT-PCR and WB indicated the mRNA or protein expression of CDH5 (Cadherin-5), SLIT2 and ROBO4 in mouse lung tissue and pulmonary vascular tissue respectively. Results: TLR4 mAb treatment decreases the pathological features of LPS induced ALI model in vivo. And so does the MPO activity as well as the level of proinflammatory factors in the lung tissue. TLR4 exerts its function through the changes of Treg/Th17 ratio via SLIT2/ROBO4 signaling pathway and downregulating CDH5 and SETSIP in ALI model. Conclusion: TLR4 mediates immune response in LPS induced ALI model through SLIT2/ROBO4 signaling pathway.

2022 ◽  
Vol 12 (1) ◽  
pp. 112-120
Author(s):  
Jieqi Gong ◽  
Huanhua Lu

The objective of this study was to investigate the molecular mechanism of the histopathological characteristics of liver cirrhosis (LC) complicated with acute kidney injury (AKI) and the signaling pathway of silent information regulator 1 (SIRT1)-peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) during the pathogenesis of LC. 20 healthy male rats with AKI complicated by laparoscopic cholecystectomy were selected and divided randomly into control group (C group), lipopolysaccharide (LPS) group, bile duct ligation (BDL) group, and model group (lipopolysaccharide+BDL) (D group). The indexes of all the rats were determined, including serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), sarcoplasmic enzyme (Scr), and blood urea nitrogen (BUN); the SIRT1 and PGC-1α expressions in renal tissues of rats from each group was detected. Results showed that the AST and ALT levels in BDL group and D group were higher markedly than those before surgery (P < 0.05). The serum levels of Scr and BUN in D group 4 hours after LPS injection increased hugely compared with before injection (P < 0.05). Compared with BDL group, the protein levels of SIRT1 and PGC-1α in renal tissue of group D were decreased sharply (P < 0.05), and the SIRT1 protein expression was positively correlated with PGC-1α (r = 0.836 and P < 0.01). When LC were complicated with AKI, SIRT1 activity was reduced and PGC-1α expression was inhibited. Moreover, SIRT1-PGC-1α signaling pathway played a protective role in pathogenesis of LC complicated with AKI.


2017 ◽  
Vol 58 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Jinmei Chen ◽  
Weijian Zhang ◽  
Lurong Zhang ◽  
Jiemin Zhang ◽  
Xiuying Chen ◽  
...  

Abstract Radiation-induced lung injury (RILI) is a common complication of thoracic radiotherapy, but efficacious therapy for RILI is lacking. This study ascertained whether glycyrrhetinic acid (GA; a functional hydrolyzed product of glycyrrhizic acid, which is extracted from herb licorice) can protect against RILI and investigated its relationship to the transforming growth factor (TGF)-β1/Smads signaling pathway. C57BL/6 mice were divided into four groups: a control group, a GA group and two irradiation (IR) groups. IR groups were exposed to a single fraction of X-rays (12 Gy) to the thorax and administered normal saline (IR + NS group) or GA (IR + GA group). Two days and 17 days after irradiation, histologic analyses were performed to assess the degree of lung injury, and the expression of TGF-β1, Smad2, Smad3 and Smad7 was recorded. GA administration mitigated the histologic changes of lung injury 2 days and 17 days after irradiation. Protein and mRNA expression of TGF-β1, Smad2 and Smad3, and the mRNA level of Smad7, in lung tissue were significantly elevated after irradiation. GA decreased expression of TGF-β1, Smad2 and Smad3 in lung tissue, but did not increase Smad7 expression. GA can protect against early-stage RILI. This protective effect may be associated with inhibition of the TGF-β1/Smads signaling pathway.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Leandro da Silva Cândido ◽  
Natália Alves de Matos ◽  
Thalles de Freitas Castro ◽  
Laisy Cristina de Paula ◽  
Aline Maria dos Santos ◽  
...  

Mechanical ventilation (MV) is essential for the treatment of critical patients since it may provide a desired gas exchange. However, MV itself can trigger ventilator-associated lung injury in patients. We hypothesized that the mechanisms of lung injury through redox imbalance might also be associated with pulmonary inflammatory status, which has not been so far described. We tested it by delivering different tidal volumes to normal lungs undergoing MV. Healthy Wistar rats were divided into spontaneously breathing animals (control group, CG), and rats were submitted to MV (controlled ventilation mode) with tidal volumes of 4 mL/kg (MVG4), 8 mL/kg (MVG8), or 12 mL/kg (MVG12), zero end-expiratory pressure (ZEEP), and normoxia ( Fi O 2 = 21 % ) for 1 hour. After ventilation and euthanasia, arterial blood, bronchoalveolar lavage fluid (BALF), and lungs were collected for subsequent analysis. MVG12 presented lower PaCO2 and bicarbonate content in the arterial blood than CG, MVG4, and MVG8. Neutrophil influx in BALF and MPO activity in lung tissue homogenate were significantly higher in MVG12 than in CG. The levels of CCL5, TNF-α, IL-1, and IL-6 in lung tissue homogenate were higher in MVG12 than in CG and MVG4. In the lung parenchyma, the lipid peroxidation was more important in MVG12 than in CG, MVG4, and MVG8, while there was more protein oxidation in MVG12 than in CG and MVG4. The stereological analysis confirmed the histological pulmonary changes in MVG12. The association of controlled mode ventilation and high tidal volume, without PEEP and normoxia, impaired pulmonary histoarchitecture and triggered redox imbalance and lung inflammation in healthy adult rats.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Shao Tenghao ◽  
Chen Ning ◽  
Wang Shenghai ◽  
Sun Qinlong ◽  
Wu Jiaqian ◽  
...  

Reducing inflammation can effectively relieve acute lung injury (ALI). Objective. To test whether keratinocyte growth factor-2 (KGF-2) can reduce oleic acid-induced inflammation in ALI of rats and explore its possible mechanism. Methods. 45 Sprague-Dawley rats were randomly divided into control group, ALI group, and ALI + KGF-2 group. The animal model of acute lung injury was established by injecting 0.1 mL/kg oleic acid into the tail vein of rats. Rats in the control group were injected with equal volume of normal saline (NS). Each group needs pretreatment 72 hours before the preparation of the acute lung injury model. The control group and ALI group were instilled with 5 ml/kg NS through the airway, and the same amount of KGF-2 was instilled in the ALI + KGF-2 group. It takes 8 hours to successfully prepare the ALI model. Observe the pathological changes of lung tissue through light microscopy, ultrastructural changes through electron microscopy, and the lung wettability/dry weight (w/d) ratio and lung permeability index (LPI). By detecting changes in inflammatory factors in lung tissue and changes in the number of BALF cells, the changes in inflammation in each group were observed. The expressions of Wnt5a, β-catenin, and APC in lung tissue were detected by immunohistochemistry and Western blot. The changes of key proteins in Wnt/β-catenin signaling pathway in the lung tissue of each group were observed. Result. Compared with the ALI group, after KGF-2 pretreatment, the degree of lung injury was reduced, the expression of inflammatory factors was reduced, and the number of red blood cells and white blood cells in BALF was reduced. It can also be observed that the expression of Wnt5a, β-catenin, and APC, a key protein in the Wnt/β-catenin signaling pathway, is reduced. The analysis showed that the number of inflammatory factors, red blood cells, and white blood cells in BALF was positively correlated with the expression of Wnt5a, β-catenin, and APC. Conclusion. KGF-2 may reduce the inflammatory response in ALI induced by oleic acid by regulating key proteins in the Wnt/β-catenin signaling pathway.


2021 ◽  
Vol 83 (1) ◽  
Author(s):  
Christian John Hurry ◽  
Alexander Mozeika ◽  
Alessia Annibale

AbstractDescribing the anti-tumour immune response as a series of cellular kinetic reactions from known immunological mechanisms, we create a mathematical model that shows the CD4$$^{+}$$ + /CD8$$^{+}$$ + T-cell ratio, T-cell infiltration and the expression of MHC-I to be interacting factors in tumour elimination. Methods from dynamical systems theory and non-equilibrium statistical mechanics are used to model the T-cell dependent anti-tumour immune response. Our model predicts a critical level of MHC-I expression which determines whether or not the tumour escapes the immune response. This critical level of MHC-I depends on the helper/cytotoxic T-cell ratio. However, our model also suggests that the immune system is robust against small changes in this ratio. We also find that T-cell infiltration and the specificity of the intra-tumour TCR repertoire will affect the critical MHC-I expression. Our work suggests that the functional form of the time evolution of MHC-I expression may explain the qualitative behaviour of tumour growth seen in patients.


2021 ◽  
Vol 49 (4) ◽  
pp. 030006052098210
Author(s):  
Quan Wang ◽  
Jingcong Luo ◽  
Ruiqiang Sun ◽  
Jia Liu

Objective Common inhalation anesthetics used for clinical anesthesia (such as sevoflurane) may induce nerve cell apoptosis during central nervous system development. Furthermore, anesthetics can produce cognitive impairments, such as learning and memory impairments, that continue into adulthood. However, the precise mechanism remains largely undefined. We aimed to determine the function of microRNA-1297 (miR-1297) in sevoflurane-induced neurotoxicity. Methods Reverse transcription-polymerase chain reaction assays were used to analyze miR-1297 expression in sevoflurane-exposed mice. MTT and lactate dehydrogenase (LDH) assays were used to measure cell growth, and neuronal apoptosis was analyzed using flow cytometry. Western blot analyses were used to measure PTEN, PI3K, Akt, and GSK3β protein expression. Results In sevoflurane-exposed mice, miR-1297 expression was up-regulated compared with the control group. MiR-1297 up-regulation led to neuronal apoptosis, inhibition of cell proliferation, and increased LDH activity in the in vitro model of sevoflurane exposure. MiR-1297 up-regulation also suppressed the Akt/GSK3β signaling pathway and induced PTEN protein expression in the in vitro model. PTEN inhibition (VO-Ohpic trihydrate) reduced PTEN protein expression and decreased the effects of miR-1297 down-regulation on neuronal apoptosis in the in vitro model. Conclusion Collectively, the results indicated that miR-1297 stimulates sevoflurane-induced neurotoxicity via the Akt/GSK3β signaling pathway by regulating PTEN expression.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yue Yang ◽  
Tingting Di ◽  
Zixiao Zhang ◽  
Jiaxin Liu ◽  
Congli Fu ◽  
...  

Abstract Background Establishment of a mouse model is important for investigating the mechanism of chronic obstructive pulmonary disease (COPD). In this study, we observed and compared the evolution of the pathology in two mouse models of COPD induced by cigarette smoke (CS) exposure alone or in combination with lipopolysaccharide (LPS). Methods One hundred eight wild-type C57BL/6 mice were equally divided into three groups: the (1) control group, (2) CS-exposed group (CS group), and (3) CS + LPS-exposed group (CS + LPS group). The body weight of the mice was recorded, and noninvasive lung function tests were performed monthly. Inflammation was evaluated by counting the number of inflammatory cells in bronchoalveolar lavage fluid and measuring the expression of the IL-6 mRNA in mouse lung tissue. Changes in pathology were assessed by performing hematoxylin and eosin and Masson staining of lung tissue sections. Results The two treatments induced emphysema and airway remodeling and decreased lung function. Emphysema was induced after 1 month of exposure to CS or CS + LPS, while airway remodeling was induced after 2 months of exposure to CS + LPS and 3 months of exposure to CS. Moreover, the mice in the CS + LPS group exhibited more severe inflammation and airway remodeling than the mice in the CS group, but the two treatments induced similar levels of emphysema. Conclusion Compared with the single CS exposure method, the CS + LPS exposure method is a more suitable model of COPD in airway remodeling research. Conversely, the CS exposure method is a more suitable model of COPD for emphysema research due to its simple operation.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A145-A145
Author(s):  
Stefano Pierini ◽  
Rashid Gabbasov ◽  
Linara Gabitova ◽  
Yumi Ohtani ◽  
Michael Klichinsky

BackgroundDespite the remarkable efficacy achieved by CAR-T therapy in hematologic malignancies, application in solid tumors has been challenging. We previously developed human CAR-M and demonstrated that adoptive cell transfer of CAR-M into xenograft models of human cancer controls tumor progression and improves overall survival [1]. Given that CAR-M are professional antigen presenting cells, we developed an immunocompetent animal model to evaluate the potential for induction of a systemic anti-tumor immune response.MethodsMurine bone marrow-derived macrophages were engineered to express an anti-HER2 CAR using the chimeric adenoviral vector Ad5f35. CAR-M were phenotypically and functionally evaluated in vitro and in syngeneic models. To evaluate CAR-M efficacy in an immunocompetent animal model, BALB/c mice were engrafted with CT26-HER2+ tumors (single-tumor model) and were treated with intratumoral CAR-HER2 or untransduced (UTD) macrophages. To evaluate epitope spreading, we simultaneously engrafted BALB/c mice with CT26-HER2+ and CT26-Wt tumors on opposite flanks (dual-tumor model), and treated mice with CAR-M or controls into the CT26-HER2+ tumor only. Peripheral and tumor-infiltrating immune cells were phenotypically and functionally characterized.ResultsIn addition to efficient gene delivery, Ad5f35 transduction promoted a pro-inflammatory (M1) phenotype in murine macrophages. CAR-M, but not control UTD macrophages, phagocytosed HER2+ target cancer cells. Anti-HER2 CAR-M eradicated HER2+ murine CT26 colorectal and human AU-565 breast cancer cells in a dose-dependent manner. CAR-M increased MHC-I and MHC-II expression on tumor cells and promoted tumor-associated antigen presentation and T cell activation. In vivo, CAR-M treatment led to tumor regression and improved overall survival in the CT26-HER2+ single-tumor model. In the dual-tumor model, CAR-M treatment cleared 75% of CT26-HER2+ tumors and inhibited the growth rate of contralateral CT26-WT tumors, demonstrating an abscopal effect. CAR-M treatment led to increased infiltration of intratumoral CD4+ and CD8+ T, NK, and dendritic cells – as well as an increase in T cell responsiveness to the CT26 MHC-I antigen gp70, indicating enhanced epitope spreading. Given the impact CAR-M had on endogenous T-cell immunity, we evaluated the combination of CAR-M and anti-PD1 in the CT26-HER2 model and found that the combination further enhanced tumor control and overall survival.ConclusionsThese results demonstrate that CAR-M therapy induces epitope spreading via activation of endogenous T cells, orchestrating a systemic immune response against solid tumors. Moreover, our findings provide rationale for the combination of CAR-M with immune checkpoint inhibitors. The anti-HER2 CAR-M CT-0508 will be evaluated in an upcoming Phase I clinical trial.ReferenceKlichinsky M, Ruella M, Shestova O, et al. Human chimeric antigen receptor macrophages for cancer immunotherapy. Nat Biotechnol 2020;38(8):947–953.


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