沙棘多糖对扑热息痛诱导的小鼠肝损伤保护作用的研究

目的：研究沙棘多糖（SP）对扑热息痛（APAP）诱导的小鼠急性肝损伤组织的保护作用和机制。方法：C57BL/6雄性小鼠随机分为6组：空白组（Ctrl）,APAP模型组（APAP,350 mg/kg),N-乙酰半胱氨酸组（NAC,150 mg/kg）,SP低剂量组（APAP/SP100,100 mg/kg）,SP高剂量（APAP/SP200,200 mg/kg）,SP对照组（SP200,200 mg/kg）,SP连续灌胃30 d,30 d后腹腔注射APAP建立急性肝损伤模型,NAC在造模前1 h腹腔注射,16 h后处死小鼠。收集血清检测AST、ALT指标,HE染色检测肝脏组织学变化,实时定量PCR检测肝组织炎症因子,Western blot检测TLR4和p-JNK表达。结果：SP降低了APAP诱导的AST和ALT水平,减轻了肝损伤,抑制了TLR4和p-JNK表达,降低了TNF-α和IL-6的水平。结论：SP通过抑制TLR4-p-JNK通路,减轻了APAP诱导的肝损伤。     

NLRP3 inflammasome activation regulated by NF-κB and DAPK contributed to paraquat-induced acute kidney injury

Paraquat can result in dysfunction of multiple organs after ingestion in human. However, the mechanisms of nucleotide-binding domain and leucine-rich repeat containing protein 3 (NLRP3) inflammasome activation in acute kidney injury have not been clearly demonstrated. The aim of this study was to determine the effect of NLRP3 inflammasome activation and its regulation by nuclear factor-kappa B (NF-κB) and death-associated protein kinase (DAPK). Male Wistar rats were treated with intraperitoneal injection of paraquat at 20 mg/kg, and NF-κB inhibitor BAY 11-7082 was pretreated at 10 mg/kg 1 h before paraquat exposure. Additionally, rat renal tubular epithelial cells (NRK-52E) were transfected with small interfering RNA (siRNA) against DAPK to evaluate its role in NLRP3 inflammasome activation. DAPK and NLRP3 inflammasome were evaluated by immunohistochemistry staining or Western blot; the pro-inflammatory cytokines including tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and interleukin-18 (IL-18) were measured via ELISA. The results showed that NF-κB, DAPK, and NLRP3 inflammasome were activated in paraquat (PQ)-treated rat kidney; the secretion of pro-inflammatory cytokines was significantly increased. These toxic effects were attenuated by NF-κB inhibitor. Besides, the activation of NLRP3 inflammasome and secretion of IL-1β and IL-18 in paraquat-treated rat renal tubular epithelial cells were inhibited by siRNA against DAPK. In conclusion, NLRP3 inflammasome activation regulated by NF-κB and DAPK played an important role in paraquat-induced acute kidney injury.     

Blockade of the Notch1/Jagged1 pathway in Kupffer cells aggravates ischemia-reperfusion injury of orthotopic liver transplantation in mice

Abstract

Liver ischemia-reperfusion injury (IRI) represents a risk factor for early graft dysfunction and an obstacle to expanding donor pool in orthotopic liver transplantation (OLT). Kupffer cells (KCs) are the largest antigen-presenting cell (APC) group and the primary modulators of inflammation in liver tissues. The vital role of Notch1/Jagged1 pathway in mouse OLT model has been reported, however, its potential therapeutic mechanism is unknown. Here, we made use of short hairpin RNA-Jagged1 and AAV-Jagged1 to explore the effects of Notch1/Jagged1 pathway in OLT. In vitro, blockade of Notch1/Jagged1 pathway downregulated the expression of Hairy and enhancer of split-1 (Hes1) gene, which in turn increased the proinflammatory effects of KCs. Moreover, the anti-inflammatory effects of Notch1/Jagged1 pathway were induced by inhibiting Hes1/gene of phosphate and tension/protein kinase B/Toll-like receptor 4/nuclear factor kappa B (Hes1/PTEN/AKT/TLR4/NF-κB) axis in KCs. In vivo, we used a well-established mouse model of OLT to mimic clinical transplantation. Mice were stochastically divided into 6 groups: Sham group (n?=?15); Normal saline (NS) group (n?=?15); Adeno-associated virus–green fluorescent protein (AAV-GFP) group (n?=?15); AAV-Jagged1 group (n?=?15); Clodronate liposome (CL) group (n = 15); CL+AAV-Jagged1 group (n = 15) . After OLT the liver damage in AAV-Jagged1 group were significantly accentuated compared to the AAV-GFP group. While blockade of Jagged1 aftet clearence of KCs by CL would not lead to further liver injuries. Taken together, our study demonstrated that blockade of Notch1/Jagged1 pathway aggravates inflammation induced by lipopolysaccharide (LPS) via Hes1/PTEN/AKT/TLR4/NF-κB in KCs, and the blockade of Notch1/Jagged1 pathway in donor liver increased neutrophil/macrophage infiltration and hepatocellular apoptosis, which suggested the function of Notch1/Jagged1 pathway in mouse OLT and highlighted the protective function of Notch1/Jagged1 pathway in liver transplantation.     

MD-2 regulates LPS-induced NLRP3 inflammasome activation and IL-1beta secretion by a MyD88/NF-κB-dependent pathway in alveolar macrophages cell line

Myeloid differentiation protein 2 (MD-2) is required in the recognition of lipopolysaccharide (LPS) by toll-like receptor 4 (TLR4), and participates in LPS-induced alveolar macrophage (AM) inflammation during acute lung injury (ALI). Activation of the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome aggravates inflammation in LPS-induced ALI. However, there is currently little known about the relationship between MD-2 signaling and the NLRP3 inflammasome. This study showed that NLRP3 expression, IL-1beta (IL-1β) secretion, and pyroptosis were up-regulated after LPS stimulation in the NR8383 AM cell-line. MD-2 gene knock-down reduced LPS-induced mRNA and protein expression of NLRP3 and IL-1β secretion in NR8383 cells, and inhibited the MyD88/NF-κB signaling pathway. Conversely, over-expression of MD-2 not only heightened NLRP3, MyD88, and NF-κB p65 protein expression, it also aggravated the LPS-induced inflammatory response. Furthermore, the NF-κB inhibitor SN50 had a beneficial role in decreasing NLRP3 and caspase-1 mRNA and protein expression. The observations suggest that MD-2 helps to regulate LPS-induced NLRP3 inflammasome activation and the inflammatory response in NR8383 cells, and likely does so by affecting MyD88/NF-κB signaling.     

DAPT阻断Notch通路对动脉粥样硬化型缺血性脑卒中大鼠的保护作用

目的:探讨DAPT阻断Notch通路对动脉粥样硬化(AS)基础上缺血性脑卒中模型大鼠的保护作用。方法:24只健康雄性SD大鼠随机分为对照(control,n=6)组和模型(n=18)组,后者建立AS模型,然后再随机分为AS假手术(AS-sham)组、AS缺血性脑卒中(AS-ischemia)组以及AS缺血性脑卒中DAPT处理(AS-ischemiaDAPT)组,每组各6只;HE染色观察大鼠颈动脉组织病理变化,全自动生化分析仪检测大鼠血液甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)水平;酶联免疫反应检测大鼠血清炎症因子白细胞介素6(IL-6)和肿瘤坏死因子α(TNF-α)的水平;Western blot检测大鼠颈动脉组织中Notch1和Hes1以及脑组织中核因子κB (NF-κB)和Toll样受体4 (TLR4)的蛋白表达水平。结果:Notch信号通路抑制剂DAPT能显著缓解AS大鼠动脉内膜层增厚以及血管狭窄,减少AS斑块形成。与AS-ischemia组大鼠相比,AS-ischemia-DAPT组大鼠血脂和炎症因子水平均显著降低(P 0. 05),且颈动脉组织中Notch1和Hes1以及脑组织中NF-κB和TLR4的蛋白表达也显著降低(P 0. 05)。结论:DAPT阻断Notch通路不仅可以改善AS缺血性脑卒中大鼠的血脂水平,还可以抑制血清炎症因子释放以及NF-κB/TLR4通路的激活,从而改善AS缺血性脑卒中的症状。     

Mild hypothermia inhibits the Notch 3 and Notch 4 activation and seizure after stroke in the rat model

Ischemic brain injury is an important cause for seizure. Mild hypothermia of the brain or the whole body is an effective way to remit the post-stroke seizure. Our previous study revealed an implication of Notch 1 and 2 in the post-stroke seizure. This study further investigated the involvement of Notch 3 and 4 in post-stroke seizure and the effect of mild hypothermia on these two factors. A global cerebral ischemia (GCI) model was conducted in Sprague Dawley rats. Seizure activity was evaluated by the frequency of seizure attacks, seizure severity scores, and seizure discharges. Seizures were frequently occurred in the first and the second 24?h after GCI, however active whole-body cooling (mild hypothermia) and DAPT (Notch inhibitor) injection into the hippocampus, alone or in combination, alleviated seizure activity after GCI. Immunohistochemistry and Western blot assays revealed the up-regulation of Notch intracellular domain (NICD) 3 and 4 in the cerebral cortex and hippocampus following GCI, but mild hypothermia and DAPT inhibited the up-regulation of NICD 3 and 4. NF-κB, PPARα, PPARγ, cyclin D1, Sox2 and Pax6 are associated with the pathogenesis of diverse type of seizures. GCI induced NF-κB, cyclin D1, and Pax6 activity, but suppressed PPARγ. These effects of GCI were abolished by both mild hypothermia and DAPT treatment. This indicated the implication of Notch signaling in the effects of GCI. Collectively, mild hypothermia inhibits Notch 3 and Notch 4 activation and seizure after stroke in the rat model. This study adds to the further understanding of the pathogenesis of post-stroke seizures and the protective mechanism of mild hypothermia.     

Lactobacillus casei Zhang 对扑热息痛诱导的小鼠急性肝损伤的保护作用

目的:研究益生菌Lactobacillus casei Zhang(Lcz)对扑热息痛(APAP)所致小鼠急性肝损伤的保护作用及其机制。方法:C57BL/6 小鼠被随机分为空白组(Ctrl)、APAP 诱导急性肝损伤模型组(Acetaminophen ,APAP)、阳性药物组(N-Acetylcysteine,NAC)、Lcz 预防组(Lcz/ APAP)和Lcz 对照组(Lcz)。Lcz(1伊109 CFU/ ml)连续灌胃30 d 后,NAC 组在APAP 处理前1 h 腹腔注NAC(150 mg/ kg)。APAP、NAC 以及Lcz/ APAP 组均腹腔注射APAP(300 mg/ kg)。APAP 作用18 h 后,采集血液和收集肝脏组织,检测血清中谷丙转氨酶(ALT)和谷草转氨酶(AST)的水平。通过Western blot 检测肝脏组织中血红素氧化酶(HO-1)、超氧化物歧化酶2(SOD2)、Bcl-2 以及TLR4 的表达水平。结果:Lcz 能抑制APAP 诱导的急性肝损伤血清中ALT 和AST 水平。Lcz 提高了HO-1、SOD2 和Bcl-2 的蛋白表达水平,而降低了APAP 诱导的TLR4 的表达。结论:益生菌Lcz对APAP 诱导的小鼠急性肝损伤有保护作用,其保肝作用机制可能与其抗氧化和抗炎活性有关。     

Fibrin(ogen)-independent role of plasminogen activators in acetaminophen-induced liver injury

Hepatic fibrin(ogen) has been noted to occur after acetaminophen (APAP)-induced liver injury in mice. Deficiency in plasminogen activator inhibitor-1 (PAI-1), an endogenous inhibitor of fibrinolysis, increases APAP-induced liver injury in mice. However, the roles of fibrinogen and fibrinolysis in APAP-induced liver injury are not known. We tested the hypothesis that hepatic fibrin(ogen) deposition reduces severity of APAP-induced liver injury. APAP-induced (300 mg/kg) liver injury in mice was accompanied by thrombin generation, consumption of plasma fibrinogen, and deposition of hepatic fibrin. Neither fibrinogen depletion with ancrod nor complete fibrinogen deficiency [via knockout of the fibrinogen alpha chain gene (Fbg(-/-))] affected APAP-induced liver injury. PAI-1 deficiency (PAI-1(-/-)) increased APAP-induced liver injury and hepatic fibrin deposition 6 hours after APAP administration, which was followed by marked hemorrhage at 24 hours. As in PAI-1(-/-) mice, administration of recombinant tissue plasminogen activator (tenecteplase, 5 mg/kg) worsened APAP-induced liver injury and hemorrhage in wild-type mice. In contrast, APAP-induced liver injury was reduced in both plasminogen-deficient mice and in wild-type mice treated with tranexamic acid, an inhibitor of plasminogen activation. Activation of matrix metalloproteinase 9 (MMP-9) paralleled injury, but MMP-9 deficiency did not affect APAP-induced liver injury. The results indicate that fibrin(ogen) does not contribute to development of APAP-induced liver injury and suggest rather that plasminogen activation contributes to APAP-induced liver injury.     

Inhibitions of NF-κB and TNF-α Result in Differential Effects in Rats with Acute on Chronic Liver Failure Induced by d-Gal and LPS

In this study, we induced an acute-on-chronic liver failure (ACLF) model by human serum albumin (HSA), d-galactosamine (d-Gal) and lipopolysaccharide (LPS) in rats. Anti-TNF-α polyclonal antibody (as TNF-α inhibitor) and pyrrolidine dithiocarbamate (PDTC, a NF-κB inhibitor) were used to treat the liver failure animals, respectively. The results showed that TNF-α inhibition was beneficial, but NF-κB inhibition failed to protect the rats in ACLF. However, HMGB1 levels, cytokine production and activation of TLR4-NF-κB signaling pathway were all suppressed by both TNF-α and NF-κB inhibition. In order to verify the effect of PDTC on inflammatory response, we further explored its effect in vitro. Anti-inflammatory activity of PDTC was proved in U937 cell line. To conclude, both inhibitions of TNF-α and NF-κB are able to suppress the activation of TLR4 and NF-κB signaling pathway. However, NF-κB inhibition with PDTC failed to protect the rats in ACLF induced by d-Gal and LPS.     

Glycyrrhizin and isoliquiritigenin suppress the LPS sensor toll-like receptor 4/MD-2 complex signaling in a different manner

Recent evidences suggest that the extracts of plant products are able to modulate innate immune responses. A saponin GL and a chalcone ILG are representative components of Glycyrrhiza uralensis, which attenuate inflammatory responses mediated by TLRs. Here, we show that GL and ILG suppress different steps of the LPS sensor TLR4/MD-2 complex signaling at the receptor level. Extract of G. uralensis suppressed IL-6 and TNF-α production induced by lipid A moiety of LPS in RAW264.7 cells. Among various G. uralensis-related components of saponins and flavanones/chalcones, GL and ILG could suppress IL-6 production induced by lipid A in dose-dependent manners in RAW264.7 cells. Furthermore, elevation of plasma TNF-α in LPS-injected mice was attenuated by passive administration of GL or ILG. GL and ILG inhibited lipid A-induced NF-κB activation in Ba/F3 cells expressing TLR4/MD-2 and CD14 and BMMs. These components also inhibited activation of MAPKs, including JNK, p38, and ERK in BMMs. In addition, GL and ILG inhibited NF-κB activation and IL-6 production induced by paclitaxel, a nonbacterial TLR4 ligand. Interestingly, GL attenuated the formation of the LPS-TLR4/MD-2 complexes, resulting in inhibition of homodimerization of TLR4. Although ILG did not affect LPS binding to TLR4/MD-2, it could inhibit LPS-induced TLR4 homodimerization. These results imply that GL and ILG modulate the TLR4/MD-2 complex at the receptor level, leading to suppress LPS-induced activation of signaling cascades and cytokine production, but their effects are exerted at different steps of TLR4/MD-2 signaling.     

Opposite roles of neutrophils and macrophages in the pathogenesis of acetaminophen-induced acute liver injury

Neutrophils and macrophages infiltrate after acetaminophen (APAP)-induced liver injury starts to develop. However, their precise roles still remain elusive. In untreated and control IgG-treated wild-type (WT) mice, intraperitoneal APAP administration (750 mg/kg) caused liver injury including centrilobular hepatic necrosis and infiltration of neutrophils and macrophages, with about 50% mortality within 48 h after the injection. APAP injection markedly augmented intrahepatic gene expression of inducible nitric oxide synthase (iNOS) and heme oxygenase (HO)-1. Moreover, neutrophils expressed iNOS, which is presumed to be an aggravating molecule for APAP-induced liver injury, while HO-1 was mainly expressed by macrophages. All anti-granulocyte antibody-treated neutropenic WT and most CXC chemokine receptor 2 (CXCR2)-deficient mice survived the same dose of APAP, with reduced neutrophil infiltration and iNOS expression, indicating the pathogenic roles of neutrophils in APAP-induced liver injury. However, APAP caused more exaggerated liver injury in CXCR2-deficient mice with reduced macrophage infiltration and HO-1 gene expression, compared with neutropenic WT mice. An HO-1 inhibitor, tin-protoporphyrin-IX, significantly increased APAP-induced mortality, implicating HO-1 as a protective molecule for APAP-induced liver injury. Thus, CXCR2 may regulate the infiltration of both iNOS-expressing neutrophils and HO-1-expressing macrophages, and the balance between these two molecules may determine the outcome of APAP-induced liver injury.     

Atorvastatin protects rat brains against permanent focal ischemia and downregulates HMGB1, HMGB1 receptors (RAGE and TLR4), NF-κB expression

Inflammatory processes play a key, mainly detrimental role in the pathophysiology of ischemic stroke. Currently, HMGB1-induced NF-κB activation pathway has been recognized as a key contributor to the proinflammatory response. It has been proved that chronic administration and pre-treatment with statins could protect brain tissue against ischemic injury. However, little is known about the effects of statins in the acute phase after cerebral ischemia. Thus, this study investigated the atorvastatin's protective role and the underlying mechanisms in cerebral ischemia. After middle cerebral artery occlusion (MCAO), atorvastatin was administered immediately. We found that atorvastatin dramatically improved neurological deficits, reduced brain water contents and infarct sizes at 24 h after stroke. Moreover, the over-expression of HMGB1, RAGE, TLR4 and NF-κB induced by ischemia was significantly attenuated by atorvastatin.     

Influence of timing of administration of liposome-encapsulated superoxide dismutase on its prevention of acetaminophen-induced liver cell necrosis in rats

The possible participation of acute oxidative stress in the in vivo mechanism by which acetaminophen (APAP) induces hepatocellular injury was examined. Male Sprague-Dawley rats were administered 3-methylcholanthrene, fasted for 18 h, then given APAP and sacrificed after a further 6 h of fasting. Extensive centrilobular liver cell necrosis along with markedly elevated serum activity of aminotransferases was observed. Liposome-encapsulated human recombinant Cu-Zn superoxide dismutase (LSOD) administered 1 or 0.5 h prior to APAP or simultaneously with the toxin completely prevented APAP-induced hepatocellular injury. In contrast, LSOD administered 5 or 2.5 h before or 1, 2.5 or 5 h after the toxin treatment did not prevent APAP toxicity. Incomplete protection against APAP-induced injury was obtained when LSOD was administered 0.5 h after the toxin. These results support the proposal of an oxidative mechanism for APAP hepatotoxicity.     

Influence of Timing of Administration of Liposome-encapsulated Superoxide Dismutase on Its Prevention of Acetaminophen-induced Liver Cell Necrosis in Rats

The possible participation of acute oxidative stress in the in vlvo mechanism by which acetaminophen (APAP) induces hepatocellular injury was examined. Male Sprague-Daw-ley rats were administered 3-methylcholanthrene, fasted for 18 h, then given APAP and sacrificed after a further 6 h of fasting. Extensive centrilobular liver cell necrosis along with markedly elevated serum activity of aminotrans-ferases was observed. Liposome-encapsulated human recombinant Cu-Zn superoxide dismutase (LSOD) administered 1 or 0.5 h prior to APAP or simultaneously with the toxin completely prevented APAP-induced hepatocellular injury. In contrast, LSOD administered 5 or 2.5 h before or 1, 2.5 or 5 h after the toxin treatment did not prevent APAP toxicity. Incomplete protection against APAP-induced injury was obtained when LSOD was administered 0.5 h after the toxin. These results support the proposal of an oxidative mechanism for APAP hepatotoxicity.     

Propofol Protects Rats and Human Alveolar Epithelial Cells Against Lipopolysaccharide-Induced Acute Lung Injury via Inhibiting HMGB1 Expression

High-mobility group box 1 (HMGB1) plays a key role in the development of acute lung injury (ALI). Propofol, a general anesthetic with anti-inflammatory properties, has been suggested to be able to modulate lipopolysaccharide (LPS)-induced ALI. In this study, we investigated the effects of propofol on the expression of HMGB1 in a rat model of LPS-induced ALI. Rats underwent intraperitoneal injection of LPS to mimic sepsis-induced ALI. Propofol bolus (1, 5, or 10 mg/kg) was infused continuously 30 min after LPS administration, followed by infusion at 5 mg/(kg?·?h) through the left femoral vein cannula. LPS increased wet to dry weight ratio and myeloperoxidase activity in lung tissues and caused the elevation of total protein and cells, neutrophils, macrophages, and neutrophils in bronchoalveolar lavage fluid (BALF). Moreover, HMGB1 and other cytokine levels were increased in BALF and lung tissues and pathological changes of lung tissues were excessively aggravated in rats after LPS administration. Propofol inhibited all the above effects. It also inhibited LPS-induced toll-like receptor (TLR)2/4 protein upexpression and NF-κB activation in lung tissues and human alveolar epithelial cells. Propofol protects rats and human alveolar epithelial cells against HMGB1 expression in a rat model of LPS-induced ALI. These effects may partially result from reductions in TLR2/4 and NF-κB activation.     

Interleukin-4 deficiency protects mice from acetaminophen-induced liver injury and inflammation by prevention of glutathione depletion

Objective

Interleukin-4 (IL-4) is a multifunctional cytokine involved in many diseases such as autoimmune hepatitis and idiosyncratic drug reactions. However, its role in acetaminophen (APAP)-induced liver injury remains unclear. Our objective was to evaluate the contribution of IL-4 to the pathogenesis of APAP-induced liver injury.

Methods

Balb/C (WT) and IL-4 knockout (IL-4^?/?) mice were orally overdosed with APAP. After 24 h, survival percentage, biochemical and morphological markers of liver injury, and tissue inflammation were assessed.

Results

IL-4^?/? mice were protected from APAP toxicity. Intravital confocal microscopy, tissue histology and serum ALT levels showed significantly less liver injury and inflammation than in the WT group, which may explain the increased survival rate of IL-4^?/? mice. In addition, IL-4^?/? mice had decreased production of tumor necrosis factor α, CXCL1 and interleukin-1β in the liver, but not in a remote site such as the lungs. Hepatic macrophage activation was markedly reduced in IL-4-deficient mice. In addition, glutathione depletion—a primary cause of APAP-mediated injury—was significantly attenuated in IL-4^?/? mice.

Conclusions

Taken together, our data demonstrate that IL-4^?/? mice are protected from APAP-induced liver injury due to reduced depletion of glutathione, which prevented liver damage and tissue inflammation.     

Quercetin Protects Mice from ConA-Induced Hepatitis by Inhibiting HMGB1-TLR Expression and Down-Regulating the Nuclear Factor Kappa B Pathway

The dietary flavonoid quercetin has hepatoprotective effects. We analyzed the effects of quercetin on concanavalin A (ConA)-induced hepatitis in mice and its underlying molecular mechanisms of action. Mice were administered quercetin (50 mg/kg body weight, i.p.) or vehicle 30 min before intravenous administration of ConA. Quercetin pretreatment significantly reduced the ConA-induced elevations in plasma aminotransferase concentrations and liver necrosis, as well as reducing serum concentrations of the pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interferon-γ, and interleukin-4. Quercetin pretreatment also reduced expression of high-mobility group box 1 protein (HMGB1) and toll-like receptor (TLR)-2 and TLR-4 messenger RNA (mRNA) and protein in liver tissues. Quercetin pretreatment significantly inhibited degradation of inhibitory kappa B alpha and modulated ConA-induced nuclear translocation in the liver of nuclear factor kappa B (NF-κB) p65. These results demonstrate that quercetin protects against ConA-mediated hepatitis in mice by attenuating the HMGB1–TLRs–NF-κB signaling pathway.     

TLR4介导汉滩病毒感染的血管内皮细胞转录因子NF-κB和IRF-3的细胞核移位

目的 观察汉滩病毒(HTNV)感染的TLR4基因沉默的EVC304细胞(TLR4~-EVC304)转录因子NF-κB和IRF-3的细胞核移位情况,为抗HTNV固有免疫及其信号转导研究提供新资料.方法 用汉滩病毒76-118株分别感染TLR4~-和TLR4~+EVC304细胞,同时以LPS作为阳性对照组,无任何刺激作为阴性对照组,6 h后用间接免疫荧光方法检测NF-κB和IRF-3的细胞核移位现象.结果 汉滩病毒76-118株刺激6 b后,在TLR4~+EVC304细胞中,NF-κB和IRF-3发生细胞核移位,而在TLR4~- EVC304细胞中未出现细胞核移位现象.结论 TLR4可能介导了HTNV感染的EVC304细胞中NF-κB和IRF-3的细胞核移位.