1.Expression of soluble Toll-like receptors in pleural effusions.
Hai-bo YANG ; Kai-qing XIE ; Jing-min DENG ; Shou-ming QIN
Chinese Medical Journal 2010;123(16):2225-2230
BACKGROUNDThe Toll-like receptors (TLRs) represent a group of single-pass transmembrane receptors expressed on sentinel cells that are central to innate immune responses.The aim of this study was to investigate the presence of soluble TLRs in pleural effusions, and the diagnostic values of TLRs for pleural effusion with various etiologies.
METHODSPleural effusion and serum samples were collected from 102 patients (36 with malignant pleural effusion, 36 with tuberculous pleural effusion, 18 with bacterial pleural effusion, and 12 with transudative pleural effusion). The concentrations of TLR1 to TLR10 were determined in effusion and serum samples by enzyme linked immunosorbent assay. Four classical parameters (protein, lactate dehydrogenase, glucose and C-reactive protein (CRP)) in the pleural fluid were also assessed. Receiver-operating characteristic curves were used to assess the sensitivity and specificity of pleural fluid TLRs and biochemical parameters for differentiating bacterial pleural effusion.
RESULTSThe concentrations of TLR1, TLR3, TLR4, TLR7 and TLR9 in bacterial pleural effusion were significantly higher than those in malignant, tuberculous, and transudative groups, respectively. Analysis of receiver operating characteristic curves revealed that the area under the curves of TLR1, TLR3, TLR4, TLR7 and TLR9 were 0.831, 0.843, 0.842, 0.883 and 0.786, respectively, suggesting that these TLRs play a role in the diagnosis of bacterial pleural effusion. Also, the diagnostic value of TLRs for bacterial pleural effusions was much better than that of biochemical parameters (protein, lactate dehydrogenase, glucose and CRP).
CONCLUSIONSThe concentrations of TLR1, TLR3, TLR4, TLR7 and TLR9 appeared to be increased in bacterial pleural effusion compared to non-bacterial pleural effusions. Determination of these pleural TLRs may improve the ability of clinicians to differentiate pleural effusion patients of bacterial origin from those with other etiologies.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Bacterial Infections ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Male ; Middle Aged ; Pleural Effusion ; metabolism ; microbiology ; Prospective Studies ; Toll-Like Receptor 1 ; metabolism ; Toll-Like Receptor 3 ; metabolism ; Toll-Like Receptor 4 ; metabolism ; Toll-Like Receptor 7 ; metabolism ; Toll-Like Receptor 9 ; metabolism ; Toll-Like Receptors ; metabolism ; Young Adult
2.Anti-herpes simplex virus type Ⅰ of tectorigenin derivative and effect on Toll-like receptors in vitro.
Yuan WANG ; Ming-Ming YUAN ; Jing ZHOU ; Xiao-Han ZHENG ; Chong-Jun YUAN ; Shuai CHEN ; Sen LUO ; Lei ZHANG
China Journal of Chinese Materia Medica 2022;47(16):4428-4435
The study investigated the inhibitory effect and mechanism of tectorigenin derivative(SGY) against herpes simplex virus type Ⅰ(HSV-1) by in vitro experiments. The cytotoxicity of SGY and positive drug acyclovir(ACV) on African green monkey kidney(Vero) cells and mouse microglia(BV-2) cells was detected by cell counting kit-8(CCK-8) method, and the maximum non-toxic concentration and median toxic concentration(TC_(50)) of the drugs were calculated. After Vero cells were infected with HSV-1, the virulence was determined by cytopathologic effects(CPE) to calculate viral titers. The inhibitory effect of the tested drugs on HSV-1-induced cytopathy in Vero cells was measured, and their modes of action were initially explored by virus adsorption, replication and inactivation. The effects of the drugs on viral load of BV-2 cells 24 h after HSV-1 infection and the Toll-like receptor(TLR) mRNA expression were detected by real-time fluorescence quantitative PCR(RT-qPCR). The maximum non-toxic concentrations of SGY against Vero and BV-2 cells were 382.804 μg·mL~(-1) and 251.78 μg·mL~(-1), respectively, and TC_(50) was 1 749.98 μg·mL~(-1) and 2 977.50 μg·mL~(-1), respectively. In Vero cell model, the half maximal inhibitory concentration(IC_(50)) of SGY against HSV-1 was 54.49 μg·mL~(-1), and the selection index(SI) was 32.12, with the mode of action of significantly inhibiting replication and directly inactivating HSV-1. RT-qPCR results showed that SGY markedly reduced the viral load in cells. The virus model group had significantly increased relative expression of TLR2, TLR3 and tumor necrosis factor receptor-associated factor 3(TRAF3) and reduced relative expression of TLR9 as compared with normal group, and after SGY intervention, the expression of TLR2, TLR3 and TRAF3 was decreased to different degrees and that of TLR9 was enhanced. The expression of inflammatory factors inducible nitric oxide synthase(iNOS), tumor necrosis factor-α(TNF-α), and interleukin-1β(IL-1β) was remarkably increased in virus model group as compared with that in normal group, and the levels of these inflammatory factors dropped after SGY intervention. In conclusion, SGY significantly inhibited and directly inactivated HSV-1 in vitro. In addition, it modulated the expression of TLR2, TLR3 and TLR9 related pathways, and suppressed the increase of inflammatory factor levels.
Animals
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Antiviral Agents/therapeutic use*
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Chlorocebus aethiops
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Herpes Simplex/pathology*
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Herpesvirus 1, Human/metabolism*
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Isoflavones
;
Mice
;
TNF Receptor-Associated Factor 3/pharmacology*
;
Toll-Like Receptor 2/metabolism*
;
Toll-Like Receptor 3/metabolism*
;
Toll-Like Receptor 9/metabolism*
;
Toll-Like Receptors/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Vero Cells
;
Virus Replication
3.Expression of Toll-Like Receptors in Verruca and Molluscum Contagiosum.
Ja Kyung KU ; Hyun Jo KWON ; Mi Yeon KIM ; Hoon KANG ; Peter I SONG ; Cheryl A ARMSTRONG ; John C ANSEL ; Hyung Ok KIM ; Young Min PARK
Journal of Korean Medical Science 2008;23(2):307-314
Recent studies indicate that several Toll-like receptors (TLRs) are implicated in recognizing viral structures and instigating immune responses against viral infections. The aim of this study is to examine the expression of TLRs and proinflammatory cytokines in viral skin diseases such as verruca vulgaris (VV) and molluscum contagiosum (MC). Reverse transcription-polymerase chain reaction and immunostaining of skin samples were performed to determine the expression of specific antiviral and proinflammatory cytokines as well as 5 TLRs (TLR2, 3, 4, 7, and 9). In normal human skin, TLR2, 4, and 7 mRNA was constitutively expressed, whereas little TLR3 and 9 mRNA was detected. Compared to normal skin (NS), TLR3 and 9 mRNA was clearly expressed in VV and MC specimens. Likewise, immunohistochemistry indicated that keratinocytes in NS constitutively expressed TLR2, 4, and 7; however, TLR3 was rarely detected and TLR9 was only weakly expressed, whereas 5 TLRs were all strongly expressed on the epidermal keratinocytes of VV and MC lesions. In addition, the mRNA expression of IFN-beta and TNF-alpha was upregulated in the VV and MC samples. Immunohistochemistry indicated that IFN-beta and TNF-alpha were predominately localized in the granular layer in the VV lesions and adjacent to the MC bodies. Our results indicated that VV and MC skin lesions expressed TLR3 and 9 in addition to IFN-beta and TNF-alpha. These viral-induced proinflammatory cytokines may play a pivotal role in cutaneous innate immune responses.
Cytokines/metabolism
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*Gene Expression Regulation
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Humans
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Immunohistochemistry/methods
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Inflammation
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Interferon-beta/biosynthesis
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Keratinocytes/cytology
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Models, Biological
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Molluscum Contagiosum/*metabolism
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Toll-Like Receptor 3/biosynthesis
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Toll-Like Receptor 9/biosynthesis
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Toll-Like Receptors/*biosynthesis
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Tumor Necrosis Factor-alpha/biosynthesis
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Warts/*metabolism
4.Expressions of Toll-like receptors 3, 4, 7, and 9 in cervical lesions and their correlation with HPV16 infection in Uighur women.
Ayshamgul HASIMU ; Lin GE ; Qiao-Zhi LI ; Rui-Ping ZHANG ; Xia GUO
Chinese Journal of Cancer 2011;30(5):344-350
Recent findings show that Toll-like receptors (TLRs) expressed in immune cells play a crucial role in the innate immune response and the subsequent induction of adaptive immune responses against microbial infection on tissue injury. Furthermore, expression of TLRs in cancer cells is associated with tumor proliferation and invasion. To explore the role of TLRs expression in cervical carcinogenesis in Uighur women, we detected the expressions of TLR3, TLR4, TLR7, and TLR9 in 25 normal cervical tissues, 64 cervical intraepithelial neoplasia (CIN) tissues, and 63 cervical squamous cell carcinoma (CSCC) tissues using immunohistochemical staining, as well as human papillomavirus type 16 (HPV16) infection using PCR. All samples used in this study were from Xinjiang Uighur women. We found the expression levels of TLR4, TLR7, and TLR9 were significantly higher in CIN and CSCC than in normal controls (P < 0.05). Up-regulation of TLR4 and TLR7 were correlated with tumor differentiation but not FIGO stage or lymph node metastasis (P > 0.05). Up-regulation of TLR9 was correlated with lymph node metastasis (P < 0.05) but not tumor differentiation or FIGO stage (P > 0.05). We also analyzed the correlation between the expressions of TLRs and HPV16 infection and found that the expressions of TLR4 and TLR9 significantly correlated with HPV16 infection in CIN (r = 7.434, P = 0.006; r = 7.123, P = 0.008) and CSCC (r = 6.423, P = 0.001; r = 8.478, P = 0.004), whereas the expression of TLR3 was not significantly different in any of the three groups and had no significant correlation with HPV16 infection. Our results suggest that high expression of TLR4, TLR7, and TLR9 may play important roles in the development and progression of CIN and CSCC in Uighur women, and the expressions of TLR4 and TLR9 can be up-regulated by HPV16 infection.
Carcinoma, Squamous Cell
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metabolism
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pathology
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virology
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Cervical Intraepithelial Neoplasia
;
metabolism
;
pathology
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virology
;
China
;
ethnology
;
Female
;
Gene Expression Regulation, Neoplastic
;
Human papillomavirus 16
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isolation & purification
;
Humans
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Lymphatic Metastasis
;
Neoplasm Staging
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Papillomavirus Infections
;
genetics
;
pathology
;
Toll-Like Receptor 3
;
metabolism
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Toll-Like Receptor 4
;
metabolism
;
Toll-Like Receptor 7
;
metabolism
;
Toll-Like Receptor 9
;
metabolism
;
Toll-Like Receptors
;
metabolism
;
Up-Regulation
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Uterine Cervical Neoplasms
;
metabolism
;
pathology
;
virology
5.Expression of Toll-like receptors in thymus of myasthenia gravis patients.
Ke GAO ; Ying-cheng WANG ; Xiao-hong MA ; Tao LI ; Zhu WU ; Lun-xu LIU ; Guo-wei CHE ; Ying-li KOU ; Yi HUANG ; Yun WANG
Chinese Journal of Medical Genetics 2008;25(3):311-314
OBJECTIVETo investigate the expression of Toll-like receptors (TLRs) in thymus of myasthenia gravis (MG) patients and the relationship with clinical features.
METHODSThymic specimens of 36 patients received extended thymectomy for MG were divided into three groups by pathological type: 13 thymoma tissues (thymoma group) and 13 thymic tissues adjacent to thymomas (parathymoma group) from 13 cases of MG patients with thymomas, and 23 thymic tissues from MG patients without thymomas (MG nonthymoma group). Twenty-one normal thymic specimens from cardiac surgery were used as controls. The levels of TLR2-4 mRNA were examined by RT-PCR, then the levels of TLR4 mRNA were assayed by real time RT-PCR and their relationship with clinical features were analyzed.
RESULTSThe levels of TLR4 mRNA among the different groups had significant differences, while there was no difference in TLR2 and TLR3 levels. The real time RT-PCR showed that the level of TLR4 mRNA in nonthymoma group was significantly higher than that in control group(0.8544+/- 0.1200 vs 0.6851+/- 0.1524, P=0.018). And so is parathymoma group compared with the thymoma group (0.8214+/- 0.1019 vs 0.7101+/- 0.0916, P=0.005). No significant difference of TLR4 mRNA level was found between the parathymoma and nonthymoma groups. Nevertheless, the expression of TLR4 in both groups was increased compared with control group. The levels of TLR4 mRNA had positive correlation with Osserman type(R=0.609; P=0.004) .
CONCLUSIONTLR4 may play a key role in the pathogenesis of MG. It was the thymic tissues adjacent to thymomas but not thymomas themselves participated in the onset of MG.
Adolescent ; Adult ; Female ; Gene Expression Regulation ; Humans ; Male ; Middle Aged ; Myasthenia Gravis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Thymus Gland ; metabolism ; Toll-Like Receptor 2 ; genetics ; Toll-Like Receptor 3 ; genetics ; Toll-Like Receptor 4 ; genetics ; Toll-Like Receptors ; genetics ; Young Adult
6.Lipopolysaccharide-enhanced early proliferation of insulin secreting NIT-1 cell is associated with nuclear factor-kappaB- mediated inhibition of caspase 3 cleavage.
Shan-Ying LIU ; Qi-Jun LIANG ; Tian-Xin LIN ; Xin-Lan FAN ; Ying LIANG ; Uwe HEEMANN ; Yan LI
Chinese Medical Journal 2011;124(22):3652-3656
BACKGROUNDIncreased levels of plasma lipopolysaccharide (LPS) have been found in obesity and diabetes patients. This study was to investigate the effect of LPS on pancreatic beta-cell viability and the involvement of caspase 3 in NIT-1 cell line.
METHODSMouse insulinoma NIT-1 cells were treated with LPS for the indicated time and dose. Cell viability was measured by cell counting kit-8 reagent. Toll-like receptor 4 (TLR4), caspase 3 and cleaved caspase 3 were detected by Western blotting. Insulin was determined by radioimmunoassay (RIA).
RESULTSLPS promoted NIT-1 cell proliferation at 1 µg/ml, peaked at 72 hours of incubation. A reduction in cleavage of caspase 3 was observed upon LPS treatment. Bay11-7082, a specific inhibitor of nuclear factor (NF)-κB, blunted LPS-induced inhibition of caspase 3 cleavage. Reduction in chronic insulin secretion was observed after treatment with LPS at 1 µg/ml for 48 and 72 hours, not for 24 hours. TLR4 protein was upregulated when NIT-1 cells were treated with LPS at 1 µg/ml for 24 hours.
CONCLUSIONSLPS promotes early NIT-1 cell proliferation in association with NF-κB-mediated inhibition of caspase 3 cleavage. LPS exerts a time-dependent inhibitory effect on chronic insulin secretion from NIT-1 cells.
Animals ; Caspase 3 ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Insulin ; secretion ; Insulinoma ; metabolism ; Lipopolysaccharides ; pharmacology ; Mice ; NF-kappa B ; metabolism ; Toll-Like Receptor 4 ; metabolism
7.The role and mechanism of autophagy in lipopolysaccharide-induced inflammatory response of A549 cells.
Jia SHI ; Hui-Xian TAO ; Yan GUO ; Yun-Su ZOU ; Mu-Zi WANG ; Zhi-Tao LU ; Yi-Fang DING ; Wei-Dong XU ; Xiao-Guang ZHOU
Chinese Journal of Contemporary Pediatrics 2022;24(10):1161-1170
OBJECTIVES:
To study the role and mechanism of autophagy in lipopolysaccharide (LPS)-induced inflammatory response of human alveolar epithelial A549 cells.
METHODS:
A549 cells were stimulated with LPS to establish a cell model of inflammatory response, and were then grouped (n=3 each) by concentration (0, 1, 5, and 10 μg/mL) and time (0, 4, 8, 12, and 24 hours). The A549 cells were treated with autophagy inhibitor 3-methyladenine (3-MA) to be divided into four groups (n=3 each): control, LPS, 3-MA, and 3-MA+LPS. The A549 cells were treated with autophagy agonist rapamycin (RAPA) to be divided into four groups (n=3 each): control, LPS, RAPA, and RAPA+LPS. The A549 cells were transfected with the Toll-like receptor 4 (TLR4) overexpression plasmid to be divided into four groups (n=3 each): TLR4 overexpression control, TLR4 overexpression, TLR4 overexpression control+LPS, and TLR4 overexpression+LPS. The A549 cells were transfected with TLR4 siRNA to be divided into four groups (n=3 each): TLR4 silencing control,TLR4 silencing, TLR4 silencing control+LPS, and TLR4 silencing+LPS. CCK-8 assay was used to measure cell viability. Western blot was used to measure the protein expression levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4.
RESULTS:
After stimulation with 1 μg/mL LPS for 12 hours, the levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4 increased and reached the peak (P<0.05). Compared with the LPS group, the 3-MA+LPS group had reduced expression of autophagy-related proteins and increased expression of inflammation-related proteins and TLR4, while the RAPA+LPS group had increased expression of autophagy-related proteins and reduced inflammation-related proteins and TLR4 (P<0.05). The TLR4 overexpression+LPS group had reduced autophagy-related proteins and increased inflammation-related proteins compared with the TLR4 overexpression control+LPS group, and the TLR4 silencing+LPS group had increased autophagy-related proteins and reduced inflammation-related proteins compared with the TLR4 silencing control+LPS group (P<0.05).
CONCLUSIONS
In the LPS-induced inflammatory response of human alveolar epithelial A549 cells, autophagic flux has a certain protective effect on A549 cells. TLR4-mediated autophagic flux negatively regulates the LPS-induced inflammatory response of A549 cells.
Humans
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A549 Cells
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Autophagy
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Beclin-1/metabolism*
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Caspase 1/metabolism*
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Inflammation
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Lipopolysaccharides/pharmacology*
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NLR Family, Pyrin Domain-Containing 3 Protein/metabolism*
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Toll-Like Receptor 4/metabolism*
8.Polyinosine-polycytidylic acid promotes excessive iodine intake induced thyroiditis in non-obese diabetic mice via Toll-like receptor 3 mediated inflammation.
Ya-nan SHI ; Feng-hua LIU ; Xiu-jie YU ; Ze-bing LIU ; Qing-xin LI ; Ji-hong YUAN ; Xiao-yi ZANG ; Lan-ying LI
Chinese Medical Journal 2013;126(4):703-710
BACKGROUNDExcessive iodine intake and viral infection are recognized as both critical factors associated with autoimmune thyroid diseases. Toll-like receptors (TLRs) have been reported to play an important role in autoimmune and inflammatory disorders. In this study, we aimed to clarify the possible mechanism of TLR3 involved in polyinosine-polycytidylic acid (poly(I:C)) promoting excessive iodine intake induced thyroiditis in non-obese diabetic (NOD) mice.
METHODSBoth NOD and BALB/c mice were randomly assigned to four groups: control group (n = 5), high iodine intake (HI) group (n = 7), poly(I:C) group (n = 7) and combination of excessive iodine and poly(I:C) injection (HIP) group (n = 7). After 8 weeks, mice were weighed and blood samples were collected. All the mice were sacrificed before dissection of spleen and thyroid gland. Then, thyroid histology, thyroid secreted hormone, expression of CD3(+) cells and TLR3 as well as inflammatory mRNA level were evaluated.
RESULTSBoth NOD and BALB/c mice from HI and HIP group represented goiter and increasing thyroid relative weight. Thyroid histology evidence indicated that only HIP group of NOD mice showed severe thyroiditis with lymphocytes infiltration in majority of thyroid tissue, severe damage of follicles and general fibrosis. Immunofluorescence staining results displayed a large number of CD3(+) cells in HIP NOD mice. Real-time polymerase chain reaction (PCR) results suggested interferon (IFN)-α increased over 30 folds and IFN-γ expression was doubled compared with control group, but interleukin (IL)-4 remained unchanged in HIP group of NOD mice thyroid. Meanwhile, over one third decrease of blood total thyroxine (TT4) and increased thyroid-stimulating hormone (TSH) was observed in HIP group of NOD mice. Only HIP group of NOD mice represented significantly elevation of TLR3 expression.
CONCLUSIONPoly(I:C) enhanced excessive dietary iodine induced thyroiditis in NOD mice through increasing TLR3 mediated inflammation.
Animals ; Female ; Inflammation ; chemically induced ; metabolism ; Iodine ; toxicity ; Mice ; Mice, Inbred NOD ; Poly I-C ; pharmacology ; Thyroiditis ; chemically induced ; immunology ; metabolism ; Toll-Like Receptor 3 ; metabolism
9.Effect of activation of Toll-like receptor signaling pathway of peripheral blood mononuclear cell in recombinant hepatitis B surface antigen immune response.
Cong JIN ; Hai Yun HAO ; Wen Xin CHEN ; Ting WANG ; Yan Di LI ; Lin Zhu YI ; Yong Liang FENG ; Su Ping WANG
Chinese Journal of Epidemiology 2022;43(4):560-565
Objective: To explore the effect and mechanism of activation of peripheral blood mononuclear cell (PBMC) Toll-like receptor (TLR3) signaling pathway in recombinant HBsAg (rHBsAg) immune response. Methods: White blood cells were collected from peripheral blood of 13 healthy donors in the preparation of blood products. PBMC was isolated and treated with Poly I:C (Poly I:C group) and PBS (control group) respectively. 48 h later, some cells were collected and the expressions of TLR3 signaling pathway proteins were detected by flow cytometry. After activating (Poly I:C group)/inactivating (control group) TLR3 signaling pathway, rHBsAg was given to both groups for 72 h, and the proportions of DC, T, B cells and their subsets in PBMC were detected by flow cytometry. Paired t-test, paired samples wilcoxon signed-rank test and canonical correlation analyses were used for statistical analysis. Results: The percentage of TLR3 protein-positive cells (19.21%) and protein expression (8 983.95), NF-κB protein expression (26 193.13), the percentage of pNF-κB protein-positive cells (13.73%) and its proportion in NF-κB (16.03%), and the percentage of pIRF3 protein-positive cells (12.64%) and its proportion in IRF3 (21.80%) in Poly I:C group were higher than those in control group (11.54%, 8 086.00, 22 340.66, 8.72%, 9.71%, 9.57%, 19.12%) (P<0.05), and the percentage of TRIF protein-positive cells (89.75%) and protein expression (304 219.54) were higher in Poly I:C group than in the control group (89.64%, 288 149.72) (P>0.05). After PBMC stimulation by rHBsAg, the proportions of mDC (2.90%), pDC (1.80%), B cell (5.31%) and plasma cell (67.71%) in Poly I:C group were significantly higher than those in the control group (1.83%, 0.81%, 4.23%, 58.82%) (P<0.05). Results of canonical correlation analysis showed that the expression of TLR3 protein was positively correlated with the proportions of plasma cells, the expression of pIRF3 protein was positively correlated with the proportions of plasma cells and mDC, and the percentage of pNF-κB protein-positive cells and the percentage of pIRF3 protein-positive cells were positively correlated with the proportion of CD4+T cells. Conclusions: Poly I:C can activate TLR3/TRIF/NF-κB and TLR3/TRIF/IRF3 signaling pathway, promote the function of downstream signaling molecules, and then promote the maturation of DC, induce the immune responses of CD4+T cell, and promote the maturation and activation of B cells and the immune response of rHBsAg.
Adaptor Proteins, Vesicular Transport/pharmacology*
;
Hepatitis B Surface Antigens
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Humans
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Immunity
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Leukocytes, Mononuclear/metabolism*
;
NF-kappa B
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Poly I-C/pharmacology*
;
Signal Transduction
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Toll-Like Receptor 3/metabolism*
;
Toll-Like Receptors
10.Regulatory effects of glutamine on Toll-like receptor 4 in neonatal rats with necrotizing enterocolitis.
Wei LI ; Xiao-Hui ZHENG ; Wei ZHOU ; Xiao RONG ; Long-Guang HUANG
Chinese Journal of Contemporary Pediatrics 2011;13(5):419-423
OBJECTIVETo study the expression of Toll-like receptor 4 (TLR-4) and caspase-3 in the intestine of neonatal rats with necrotizing enterocolitis (NEC), and explore the protective effects and possible regulatory mechanisms of glutamine (Gln) in NEC.
METHODSSixty premature rats were randomly divided into three groups (n=20 each): control, NEC model and Gln intervention group. NEC model was prepared by formula feeding, hypoxia and cold stress. The Gln intervention group was also subjected to hypoxia and cold stress but was fed with formula containing Gln (0.3 g/kg). Two days later, the rats were sacrificed and the intestine tissues were obtained. The histological changes of ileal tissues were observed by hemetoxylin and eosin staining. The expression of caspase-3 and TLR-4 protein in the jejunum, ileum and colon were detected by inmunohistochemistry. The expression of TLR-4 mRNA in the jejunum, ileum and colon were detected by RT-PCR.
RESULTSCompared with the control group, the histological score of ileal tissues, and the expression of caspase-3, TLR-4 protein and TLR-4 mRNA in the NEC model group increased significantly (P<0.01). Gln intervention decreased significantly the histological score of ileal tissues, and the expression of caspase-3, TLR-4 protein and TLR-4 mRNA compared with the NEC model group (P<0.05).
CONCLUSIONSTLR-4 might be involved in the pathogenesis of NEC. Gln may provide protective effects on intestine possibly through reducing the TLR-4 expression and then decreasing the apoptosis of intestinal epithelial cells.
Animals ; Animals, Newborn ; Caspase 3 ; analysis ; Enterocolitis, Necrotizing ; metabolism ; pathology ; Female ; Glutamine ; pharmacology ; Immunohistochemistry ; Pregnancy ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Toll-Like Receptor 4 ; analysis ; genetics