颗粒溶素的研究进展

颗粒溶素具有溶细胞作用和杀菌活性,其作用对象包括肿瘤细胞、细菌、真菌和寄生虫。颗粒溶素是T淋巴细胞、单核细胞和其他炎性细胞的化学刺激物,可以激活许多细胞因子的表达,包括调节激活T细胞表达和分泌(RANTES)、单核细胞化学引诱物蛋白(MCP)1、MCP3、巨噬细胞炎性蛋白1(MIP)、白介素(IL)-10、IL-1、IL-6和干扰素(IFN)-α。颗粒溶素与感染、癌症、移植、自身免疫、皮肤和生殖疾病等多种疾病相关。基于颗粒溶素的多功能性,本文针对其作用机制和与临床常见疾病关系做一综述。     

趋化因子与哺乳动物生殖

趋化因子(chemokine)通过其G蛋白偶联的受体介导白细胞在各种组织内迁移。最近发现,白细胞介素—8(IL-8)、单核细胞趋化蛋白—1(MCP—1)、调节激活的正常T细胞表达和分泌的蛋白(RANTES)、调节生长的原癌基因α(GRO-α)、粒细胞趋化蛋白—2(GCP—2)等趋化因子在卵泡发育、闭锁、排卵、类固醇激素生成、黄体功能、月经周期、着床、子宫颈成熟、早产和子宫内膜异位症等生殖过程中具有重要的调节作用。     

白细胞介素22的研究进展

白细胞介素-22（IL-22）起初系在鼠T淋巴细胞中经IL-9诱生而获得的,并因此被命名为IL-TIF（IL-10-related -derived inducible factor);鉴于其与IL-10的结构相似性,其受体是一个巳建立的细胞因子受体家族的新成员,以及其在白细胞内的产物和作用的确认,2000年由Xie等提出将其命名为一个新的人类细胞因子白细胞介素-22（IL-22）。实验证明IL-22上调肝细胞急性期产物,参与炎症反应。借助IL-9或CD3抗体和刀豆蛋白A的激活,T细胞、肥大细胞、胸腺和脑均可表达IL-22,表明这个因子在免疫系统内外可能显示多效的活性,在抗体免疫应答中,其对来自TH2T细胞的IL-4产物有适当的抑制作用,对于哮喘有潜在的治疗作用。在信号转导途径中,IL-22能介导STAT1、STAT3和STAT5的激活。     

颗粒溶素和穿孔素真核共表达及其对A549细胞的影响

目的：克隆人颗粒溶素和穿孔素基因并构建真核表达载体pGNLY-2A-PFP,观察其在人肺癌A549细胞中的表达情况。方法：体外分离培养外周血单个核细胞并抽提总RNA,RT-PCR扩增人颗粒溶素和穿孔素的基因片段,并将其分别插入pMD18-T进行测序,鉴定正确后构建pIRES-GNLY、pIRES-PFP及pGNLY-2A-PFP并转染人肺癌A549细胞,RT-PCR和间接免疫荧光检测目的蛋白表达,流式细胞Annexin V/PI检测转染后细胞凋亡情况。结果：成功获取了人颗粒溶素和穿孔素cDNA,构建了真核表达载体pIRES-GNLY、pIRES-PFP、pGNLY-2A-PFP,转染A549细胞后检测出了目的蛋白的表达,pGNLY-2A-PFP转染组细胞死亡率高于其他对照组（P<0.05）,死亡细胞以凋亡为主。结论：人颗粒溶素和穿孔素基因可以在人肺癌A549细胞中表达,二者共表达能够促进细胞凋亡,这将有助于颗粒溶素和穿孔素在肿瘤治疗中应用的后续研究。     

白介素-17在牙龈上皮细胞中调控趋化因子的机制研究

目的：有研究发现白介素-17（IL-17）作为炎症反应的重要标志物在炎症反应中具有重要作用,并且其表达水平的高低与牙周疾病的严重程度有着正相关性,但是目前为止白介素-17对于牙龈上皮细胞的趋化因子生成的影响尚没有研究,所以本课题主要探索在牙龈上皮细胞（human gingival epithelial cells,HGECs）中白介素-17如何通过趋化因子调控炎症反应,并进一步探究其作用机制。方法：酶联免疫吸附剂测定法（enzyme linked immunosorbent assay,ELISA）观察细胞中相关趋化因子分泌,同时蛋白印迹法（western blot）观察细胞中核转录因子κB的变化。结果：无IL-17刺激组与IL-17刺激组比较,IL-17刺激组的趋化因子白介素8（CXCL8）分泌量显著性增加而另一趋化因子单核细胞趋化蛋白-1（CCL2）却没有显著变化,并且通过磷酸化IκB的表达量显著性增加提示NF-κB被激活（P〈0.05）;同时IL-17刺激组与IL-17＋NF-κB抑制剂组比较,IL-17＋NF-κB抑制剂组的CXCL8分泌量显著降低,而通过磷酸化IκB的表达量显著减少提示NF-κB的活性被抑制（P〈0.05）。结论：NF-κB对IL-17刺激下的牙龈上皮细胞趋化因子的表达调控具有关键性作用,同时可能也为将来治疗IL-17诱导的牙周炎症性疾病提供了新的靶点。     

白介素-17 在牙龈上皮细胞中调控趋化因子的机制研究

目的：有研究发现白介素-17（IL-17）作为炎症反应的重要标志物在炎症反应中具有重要作用,并且其表达水平的高低与牙 周疾病的严重程度有着正相关性,但是目前为止白介素-17 对于牙龈上皮细胞的趋化因子生成的影响尚没有研究,所以本课题主 要探索在牙龈上皮细胞（human gingival epithelial cells,HGECs）中白介素-17 如何通过趋化因子调控炎症反应,并进一步探究其 作用机制。方法：酶联免疫吸附剂测定法（enzyme linked immunosorbent assay,ELISA）观察细胞中相关趋化因子分泌,同时蛋白印 迹法（western blot）观察细胞中核转录因子κB的变化。结果：无IL-17 刺激组与IL-17 刺激组比较,IL-17 刺激组的趋化因子白介 素8（CXCL8）分泌量显著性增加而另一趋化因子单核细胞趋化蛋白-1（CCL2）却没有显著变化,并且通过磷酸化I资B 的表达量显 著性增加提示NF-κB 被激活(P<0.05);同时IL-17 刺激组与IL-17+NF-κB抑制剂组比较,IL-17 +NF-κB抑制剂组的CXCL8 分泌 量显著降低,而通过磷酸化I资B的表达量显著减少提示NF-κB 的活性被抑制(P<0.05)。结论：NF-κB 对IL-17 刺激下的牙龈上皮 细胞趋化因子的表达调控具有关键性作用,同时可能也为将来治疗IL-17 诱导的牙周炎症性疾病提供了新的靶点。     

白细胞介素13及其研究进展

白细胞介素13(IL-13)是最近被发现的一种新型细胞因子,由激活的辅助T细胞产生,其分泌产物主要是一种分子量约为10000的非糖基化的单链蛋白.人和鼠IL-13成熟蛋白分别由112和111个氨基酸残基组成,IL-13不仅对单核细胞的体外生长、表面抗原表达以及多种细胞因子的产生具有明显的调控作用,而且对B细胞的增殖、分化以及免疫球蛋白合成同样具有调控作用.更引人注目的是,在造血祖细胞的增植分化调控中,IL-13与其他造血生长因子有协同作用.     

CUL1基因对MPP+诱导的SH-SY5Y细胞存活和NLRP3炎症体通路的影响

摘要 目的：探究Cullin1（CUL1）基因对1-甲基-4-苯基吡啶离子（MPP+）诱导的SH-SY5Y细胞存活和核苷酸结合寡聚化结构域样受体3（NLRP3）炎症体通路的影响。方法：（1）将SH-SY5Y细胞分为NC组、NC-sh组、CUL1-sh组、NC-OE组和CUL1-OE组。使用Lipofectamine 2000试剂对细胞转染相应的慢病毒。（2）将SH-SY5Y细胞分为Control组、MPP+组和MPP++CUL1-OE组。MPP+组和MPP++CUL1-OE组细胞使用1 mmol/L的MPP+处理48 h,Control组细胞正常培养。通过MTT法检测细胞增殖,通过Annexin V-FITC/PI双染色法和TUNEL染色法检测细胞凋亡,通过qRT-PCR检测CUL1的mRNA水平,通过Western blot检测CUL1、NLRP3、凋亡相关斑点样蛋白（ASC）、cleaved caspase-1、白细胞介素（IL）-1β和IL-18蛋白水平。通过ELISA法检测细胞培养上清液中IL-1β和IL-18水平。结果：（1）与NC组和NC-sh组比较,CUL1-sh组CUL1的mRNA和蛋白相对表达量降低,相对细胞活力降低,Annexin V-FITC/PI阳性率和TUNEL阳性率升高,NLRP3、ASC、cleaved caspase-1、IL-1β和IL-18蛋白相对表达量以及细胞培养上清液中IL-1β和IL-18水平升高（P<0.05）。与NC组和NC-OE组比较,CUL1-OE组CUL1的mRNA和蛋白相对表达量升高,相对细胞活力升高,Annexin V-FITC/PI阳性率和TUNEL阳性率降低,NLRP3、ASC、cleaved caspase-1、IL-1β和IL-18蛋白相对表达量以及细胞培养上清液中IL-1β和IL-18水平降低（P<0.05）。（2）与Control组比较,MPP+组CUL1的mRNA和蛋白相对表达量降低,相对细胞活力降低,Annexin V-FITC/PI阳性率和TUNEL阳性率升高,NLRP3、ASC、cleaved caspase-1、IL-1β和IL-18蛋白相对表达量以及细胞培养上清液中IL-1β和IL-18水平升高（P<0.05）。与MPP+组比较,MPP++CUL1-OE组CUL1的mRNA和蛋白相对表达量升高,相对细胞活力升高,Annexin V-FITC/PI阳性率和TUNEL阳性率降低,NLRP3、ASC、cleaved caspase-1、IL-1β和IL-18蛋白相对表达量以及细胞培养上清液中IL-1β和IL-18水平降低（P<0.05）。结论：CUL1可能通过抑制NLRP3炎症体激活促进MPP+诱导的SH-SY5Y细胞存活。     

TAK1基因沉默对TNF-a诱导的滑膜细胞IL-6、IL-8表达的影响

目的：观察转化生长因子β激活激酶1（TAK1）基因沉默对肿瘤坏死因子a （TNF-a）诱导的滑膜细胞中促炎介质白介素-6（IL-6）和白介素-8（IL-8）表达的影响,以探讨TAK1在类风湿关节炎（RA）发病中的作用。方法：采取脂质体转染方法将TAK1特异性的小干扰RNA （siRNA）和阴性对照RNA （scRNA）导入类风湿关节炎的滑膜成纤维细胞株MH7A细胞,然后分别用20 ng/ml TNF-a刺激后,检测细胞内IL-6、IL-8 mRNA的表达和培养上清中IL-6和IL-8分泌情况以及p38、ERK、JNK、p65磷酸化的水平和抑制性蛋白IκBα的变化情况。结果：siRNA-TAK1转染72 h后滑膜细胞中TAK mRNA和蛋白表达的平均抑制率分别为75%和55%。siRNA-TAK1转染下调TNF-a诱导状态下IL-6和IL-8的表达,并能抑制p38、JNK、p65磷酸化和增加IκBα水平。结论：TAK1基因沉默能抑制TNF-a诱导的滑膜细胞IL-6、IL-8表达,可能与其抑制JNK和p38MAPK的活化及NF-κB的活化有关。     

聚合度7-15的壳寡糖抑制脂多糖刺激的单核细胞产生TNF-α和IL-8的作用研究

本文通过建立脂多糖刺激的单核细胞炎症损伤模型,观察聚合度7-15的壳寡糖对炎性单核细胞白细胞介素-8(IL-8)和肿瘤坏死因子-α(TNF-α)表达的影响,及对p38丝裂原激活的蛋白激酶(p38 mitogen-activated protein kinases,p38MAPK)信号通路磷酸化的影响。采用p38信号通路抑制剂(SB203580)验证抑制p38信号通路对脂多糖诱导的单核细胞表达IL-8和TNF-α的作用,从而探索壳寡糖抑制单核细胞炎性损伤的分子机制。结果表明壳寡糖可抑制脂多糖诱导的单核细胞表达IL-8和TNF-α,并且抑制p38信号蛋白的磷酸化水平。因此,初步认为壳寡糖可能通过抑制炎性U937细胞中p38MAPK信号通路抑制IL-8和TNF-α的表达。     

Granulysin, a cytolytic molecule, is also a chemoattractant and proinflammatory activator

Granulysin, a cationic protein produced by activated human CTL and NK cells, is cytolytic against microbial and tumor targets. In this study we show that granulysin also functions as a chemoattractant and activates monocytes to produce cytokines/chemokines. Although granulysin-mediated cytotoxicity occurs at micromolar concentrations, chemoattraction occurs in the nanomolar range, and immune activation occurs over a wide range of concentrations (nanomolar to micromolar). Granulysin causes a 2- to 7-fold increase in chemotaxis of monocytes, CD4(+), and CD8(+) memory (CD45RO) but not naive (CD45RA) T cells, NK cells, and mature, but not immature, monocyte-derived dendritic cells. Pertussis toxin treatment abrogates chemoattraction by granulysin, indicating involvement of G-protein-coupled receptor(s). At low concentrations (10 nM), granulysin promotes a 3- to 10-fold increase in MCP-1 and RANTES produced by monocytes and U937 cells, while a 2-fold increase in TNF-alpha production by LPS-stimulated monocytes requires higher concentrations of granulysin (micromolar). Taken together, these data indicate that the local concentration of granulysin is critical for the biologic activity, with high concentrations resulting in cytotoxicity while lower concentrations, presumably further from the site of granulysin release, actively recruit immune cells to sites of inflammation.     

Thiazolidinedione inhibits the production of monocyte chemoattractant protein-1 in cytokine-treated human vascular endothelial cells.

The chemokine monocyte chemoattractant protein-1 is a potent chemoattractant for monocytes. Monocyte chemoattractant protein-1 is produced by vascular endothelial cells during inflammatory diseases such as atherosclerosis. In this study, we examined the effects of a thiazolidinedione on monocyte chemoattractant protein-1 expression in human vascular endothelial cells. In human vascular endothelial cells, interleukin-1beta and tumor necrosis factor-alpha induced endogenous monocyte chemoattractant protein-1 protein secretion, mRNA expression and promoter activity. The thiazolidinedione inhibited these effects. In summary, our results indicated that the suppression of the expression of monocyte chemoattractant protein-1 can be accomplished by thiazolidinedione treatment, raising the possibility that thiazolidinedione may be of therapeutic value in the treatment of diseases such as atherosclerosis.     

IFN-gamma-inducible protein 10 (IP-10; CXCL10)-deficient mice reveal a role for IP-10 in effector T cell generation and trafficking

IFN-gamma-inducible protein 10 (IP-10, CXCL10), a chemokine secreted from cells stimulated with type I and II IFNs and LPS, is a chemoattractant for activated T cells. Expression of IP-10 is seen in many Th1-type inflammatory diseases, where it is thought to play an important role in recruiting activated T cells into sites of tissue inflammation. To determine the in vivo function of IP-10, we constructed an IP-10-deficient mouse (IP-10(-/-)) by targeted gene disruption. Immunological analysis revealed that IP-10(-/-) mice had impaired T cell responses. T cell proliferation to allogeneic and antigenic stimulation and IFN-gamma secretion in response to antigenic challenge were impaired in IP-10(-/-) mice. In addition, IP-10(-/-) mice exhibited an impaired contact hypersensitivity response, characterized by decreased ear swelling and reduced inflammatory cell infiltrates. T cells recovered from draining lymph nodes also had a decreased proliferative response to Ag restimulation. Furthermore, IP-10(-/-) mice infected with a neurotropic mouse hepatitis virus had an impaired ability to control viral replication in the brain. This was associated with decreased recruitment of CD4(+) and CD8(+) lymphocytes into the brain, reduced levels of IFN-gamma and the IFN-gamma-induced chemokines monokine induced by IFN-gamma (Mig, CXCL9) and IFN-inducible T cell alpha chemoattractant (I-TAC, CXCL11) in the brain, decreased numbers of virus-specific IFN-gamma-secreting CD8(+) cells in the spleen, and reduced levels of demyelination in the CNS. Taken together, our data suggest a role for IP-10 in both effector T cell generation and trafficking in vivo.     

Multiple chemokine receptors, including CCR6 and CXCR3, regulate antigen-induced T cell homing to the human asthmatic airway

Human allergic asthma is a chronic inflammatory disease of the airways thought to be driven by allergen-specific Th2 cells, which are recruited into the lung in response to inhaled allergen. To identify chemoattractant receptors that control this homing pattern, we used endobronchial segmental allergen challenge in human atopic asthmatics to define the pattern of chemoattractant receptor expression on recruited T cells as well as the numbers of recruited CD1d-restricted NKT cells and levels of chemokines in the bronchoalveolar (BAL) fluid. CD1d-restricted NKT cells comprised only a small minority of BAL T cells before or after Ag challenge. BAL T cells were enriched in their expression of specific chemoattractant receptors compared with peripheral blood T cells prechallenge, including CCR5, CCR6, CXCR3, CXCR4, and BLT1. Surprisingly, following segmental allergen challenge, no chemoattractant receptor was specifically increased. However, CCR6 and CXCR3, which were expressed on virtually all CD4(+) BAL T cells prechallenge, were markedly decreased on all recruited BAL T cells following Ag challenge, suggesting that these receptors were internalized following encounter with ligand in the airway. Our data therefore suggests a role for CCR6 and CXCR3, in conjunction with other chemoattractant receptors, in the recruitment of inflammatory T cells into the BAL during the allergic asthmatic response.     

Role of chemokines and formyl peptides in pneumococcal pneumonia-induced monocyte/macrophage recruitment

Host-derived chemoattractant factors are suggested to play crucial roles in leukocyte recruitment elicited by inflammatory stimuli in vitro and in vivo. However, in the case of acute bacterial infections, pathogen-derived chemoattractant factors are also present, and it has not yet been clarified how cross-talk between chemoattractant receptors orchestrates diapedesis of leukocytes in this context of complex chemoattractant arrays. To investigate the role of chemokine (host-derived) and formyl peptide (pathogen-derived) chemoattractants in leukocyte extravasation in life-threatening infectious diseases, we used a mouse model of pneumococcal pneumonia. We found an increase in mRNA expression of eight chemokines (RANTES, macrophage-inflammatory protein (MIP)-1alpha, MIP-1beta, MIP-2, IP-10, monocyte chemoattractant protein (MCP)-1, T cell activation 3, and KC) within the lungs during the course of infection. KC and MIP-2 protein expression closely preceded pulmonary neutrophil recruitment, whereas MCP-1 protein production coincided more closely than MIP-1alpha with the kinetics of macrophage infiltration. In situ hybridization of MCP-1 mRNA suggested that MCP-1 expression started at peribronchovascular regions and expanded to alveoli-facing epithelial cells and infiltrated macrophages. Interestingly, administration of a neutralizing Ab against MCP-1, RANTES, or MIP-1alpha alone did not prevent macrophage infiltration into infected alveoli, whereas combination of the three Abs significantly reduced macrophage infiltration without affecting neutrophil recruitment. The use of an antagonist to N-formyl peptides, N-t-Boc-Phe-D-Leu-Phe-D-Leu-Phe, reduced both macrophages and neutrophils significantly. These data demonstrate that a complex chemokine network is activated in response to pulmonary pneumococcal infection, and also suggest an important role for fMLP receptor in monocyte/macrophage recruitment in that model.     

TNF receptor signaling contributes to chemokine secretion, inflammation, and respiratory deficits during Pneumocystis pneumonia

CD8(+) T cells contribute to the pathophysiology of Pneumocystis pneumonia (PcP) in a murine model of AIDS-related disease. The present studies were undertaken to more precisely define the mechanisms by which these immune cells mediate the inflammatory response that leads to lung injury. Experimental mice were depleted of either CD4(+) T cells or both CD4(+) and CD8(+) T cells and then infected with Pneumocystis: The CD4(+)-depleted mice had significantly greater pulmonary TNF-alpha levels than mice depleted of both CD4(+) and CD8(+) T cells. Elevated TNF-alpha levels were associated with increased lung concentrations of the chemokines RANTES, monocyte chemoattractant protein 1, macrophage-inflammatory protein 2, and cytokine-induced neutrophil chemoattractant. To determine whether TNFR signaling was involved in the CD8(+) T cell-dependent chemokine response, TNFRI- and II-deficient mice were CD4(+) depleted and infected with Pneumocystis: TNFR-deficient mice had significantly reduced pulmonary RANTES, monocyte chemoattractant protein 1, macrophage-inflammatory protein 2, and cytokine-induced neutrophil chemoattractant responses, reduced inflammatory cell recruitment to the alveoli, and reduced histological evidence of PcP-related alveolitis as compared with infected wild-type mice. Diminished pulmonary inflammation correlated with improved surfactant activity and improved pulmonary function in the TNFR-deficient mice. These data indicate that TNFR signaling is required for maximal CD8(+) T cell-dependent pulmonary inflammation and lung injury during PcP and also demonstrate that CD8(+) T cells can use TNFR signaling pathways to respond to an extracellular fungal pathogen.     

Shrimp anti-lipopolysaccharide factor (SALF), an antimicrobial peptide,inhibits proinflammatory cytokine expressions through the MAPK and NF-κB pathways in LPS-induced HeLa cells

Recently, an antimicrobial peptide (AMP), the shrimp anti-lipopolysaccharide factor (SALF), was shown to act against vaginal pathogens as demonstrated by a minimum inhibitory concentration (MIC) assay and suggested that the SALF might play a protective role in orchestrating various defensive responses. The demonstration of a protective role of the SALF in cervical cancer epithelial cells (HeLa cells) led us to investigate the anti-inflammatory effects of the SALF by determining its inhibitory effects on proinflammatory markers in LPS-stimulated cervical cancer HeLa cells. The SALF was shown to inhibit the production of inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-1α, and monocyte chemoattractant protein (MCP)-1 according to an ELISA analysis. The SALF also suppressed mRNA levels of il-6, il-8, il-1α, and mcp-1 according to an RT-PCR. We also found that the SALF might regulate vaginal epithelial cell immune responses through the MAPK and NF-κB pathways. These findings suggest that the SALF is a potential drug candidate for treating chronic inflammatory diseases, such as urethritis, vaginitis, cervicitis, and pelvic inflammatory diseases.     

高速泳动族蛋白1的致炎症作用机制

高速泳动族蛋白1(high-mobility group box 1,HMGB1)是一种高度保守的DNA结合蛋白,具有维持核小体结构和调节基因转录的功能,近来发现它是炎性反应强有力的促炎因子。在大多炎性疾病,特别是脓毒症病例中,HMGB1的血清和组织水平均显著升高,而且它与其受体如糖基化终末产物受体(receptor for advanced glycation end products,RAGE)、Toll样受体4(toll-like receptor,TLR4)、Toll样受体2(TLR2)等相互作用促进炎性疾病的发展。为了进一步了解HMGB1,本文就HMGB1的结构、生物学活性、与免疫细胞相互作用、细胞表面受体、以及拮抗HMGB1的药物等进行综述。