IL-17A对慢性阻塞性肺疾病的干预作用及其机制*

目的:探讨白细胞介素-17A(IL-17A)对慢性阻塞性肺疾病(COPD)的干预作用及其机制。方法:C57BL/6小鼠随机分为野生型空白对照组、野生型COPD组和IL-7A敲除COPD组,每组20只。野生型空白对照组小鼠不做任何处理,其余两组小鼠暴露于香烟烟雾(1支/次,4次/日,每次45 min,每次间隔时间为1 h,总干预时间为90 d)制作COPD模型。干预结束24 h后,利用动物肺功能检测系统测定小鼠肺功能。收集小鼠支气管肺泡灌洗液(BALF),测定BALF细胞计数和分类。收集小鼠肺组织,采用流式细胞法测定气道上皮IL-17A表达水平,采用酶联免疫吸附法测定肺组织炎症因子水平。采用蛋白免疫印迹法测定小鼠肺组织JNK/AP1信号通路蛋白表达水平。结果:与野生型空白对照组小鼠比较,野生型COPD组小鼠气道上皮IL-17A表达水平明显升高,吸气峰流速(PIF)和呼气峰流速(PEF)明显降低,BALF中性粒细胞、嗜酸性粒细胞、淋巴细胞和巨噬细胞数明显升高,肺组织CXC类趋化因子1(CXCL1)、CXC类趋化因子2(CXCL2)、白细胞介素-1β(IL-1β)和白细胞介素-6(IL-6)表达水平明显升高,JNK、cJun和cFos磷酸化水平及AP1表达水平明显升高(P＜0.05);与野生型COPD组小鼠比较,IL-7A敲除COPD组小鼠气道上皮IL-17A表达水平明显降低,PIF和PEF明显升高,BALF中性粒细胞、嗜酸性粒细胞、淋巴细胞和巨噬细胞数明显降低,肺组织CXCL1、CXCL2、IL-1β和IL-6表达水平明显降低,JNK、cJun和cFos磷酸化水平及AP1表达水平明显降低(P＜0.05)。结论:香烟烟雾可诱导小鼠气道上皮产生IL-17A,降低(或抑制)IL-17A的产生(或表达或分泌),通过抑制JNK/AP1信号通路,减轻COPD气道炎症反应,改善COPD小鼠肺功能。     

粉尘螨1类变应原Der f1 T细胞表位疫苗对哮喘小鼠特异性免疫治疗的实验研究

目的探讨粉尘螨1类变应原Der f1T细胞表位疫苗对哮喘小鼠特异性免疫治疗的效果。方法30只小鼠按每组10只随机分为三组,PBS组、哮喘组和免疫治疗组。哮喘组和免疫治疗组分别在第0、7、14天经小鼠腹腔注射100μL含100μg/mL Der f1的致敏液[含2%Al(OH)3的PBS液],PBS组以PBS液[含2%Al(OH)3]代替。哮喘组和免疫治疗组自第21天起,雾化吸入上述致敏液,PBS组雾化吸入上述PBS液,每天雾化30min,连续雾化7d。免疫治疗组在第25~27天雾化前30min,经腹腔注射100μg/mL的Der f1T细胞表位蛋白200μL,进行特异性免疫治疗,PBS组以PBS液代替。最后一次雾化吸入24h后处死小鼠,收集每组小鼠的支气管肺泡灌洗液(BALF)和血清并计数BALF中嗜酸性粒细胞,取肺组织制作肺组织病理切片,取脾脏分离脾细胞加入Der f1共培养制成脾细胞培养上清。ELISA检测BALF和脾细胞培养上清中IL-13和IFN-γ含量及血清中特异性IgE(sIgE)和IgG2a水平。结果肺组织病理切片镜检说明,免疫治疗组比哮喘组炎症明显好转,炎症细胞浸润减少。小鼠BALF中嗜酸性粒细胞数结果为免疫治疗组嗜酸性粒细胞数明显低于哮喘组(P0.01)。BALF中IL-13含量免疫治疗组明显低于哮喘组(P0.01),而IFN-γ含量与IL-13含量变化相反,免疫治疗组明显高于哮喘组(P0.01)。各组脾细胞培养上清中IL-13,免疫治疗组明显低于哮喘组(P0.01),而IFN-γ含量与IL-13含量变化相反,免疫治疗组明显高于哮喘组(P0.01)。血清中特异性IgE含量结果为免疫治疗组明显低于哮喘组(P0.01),IgG2a变化水平与IgE变化正好相反,免疫治疗组明显高于哮喘组(P0.01)。结论 Der f1T细胞表位疫苗能有效缓解哮喘小鼠的炎症反应并纠正Th1/Th2失衡。     

颗粒蛋白前体通过抑制IL-6表达减轻哮喘气道炎症

目的: 探究颗粒蛋白前体(PGRN)在过敏性哮喘中的作用及机制。方法: 分别在野生鼠和IL-6 缺陷鼠中设置对照组和哮喘模型组,每组8只。模型组中,在第0日和第7日致敏小鼠(腹腔注射OVA 100 μg),从第14日起连续激发8 d(5％OVA雾化吸入,30 min/d,每日1次),末次激发24 h后取标本;对照组用PBS代替OVA做相同处理。采集支气管肺泡灌洗液(BALF)进行白细胞计数和分类计数;HE染色观察肺组织病理情况;Q-PCR及ELISA检测小鼠肺匀浆、血清和BALF中细胞因子水平。用IL-13刺激A549或BEAS-2B细胞建立体外哮喘炎症模型,每组3个复孔,共4组:PBS处理组、IL-13处理组、IL-13与重组人PGRN蛋白(rhPGRN)共同处理组及p38磷酸化抑制剂(SB203508)处理组。0 min~48 h后收集细胞及上清,用Q-PCR及ELISA检测PGRN和IL-6的表达;Western blot检测p38的磷酸化。结果: 与对照组相比,哮喘组小鼠肺匀浆和BALF中PGRN均显著降低(P＜ 0.01),血清PGRN有降低的趋势,然而哮喘小鼠BALF中IL-6显著升高(P＜0.05)。与野生鼠哮喘组相比,IL-6缺陷鼠哮喘组BALF中白细胞总数降低(P＜0.05),中性粒细胞数降低(P＜0.05),PGRN显著升高(P＜0.05),肺部病理损伤也减轻。体外实验中,IL-13处理组与PBS处理组相比,PGRN显著降低(P＜0.05),IL-6显著增高(P＜ 0.05),p38的磷酸化增加;p38抑制剂处理组比未处理组中IL-6水平降低(P＜0.05)。IL-13与rhPGRN共同处理组的IL-6显著低于IL-13处理组(P＜0.05),p38的磷酸化降低(P＜0.05)。结论: PGRN通过抑制p38磷酸化降低IL-6水平从而减轻哮喘小鼠气道炎症。     

不同免疫抑制剂对小鼠罹患侵袭性肺曲霉病的影响

目的比较两种免疫抑制状态造成侵袭性曲霉感染(IPA)后天然免疫反应的异同。方法清洁级雄性BALB/c小鼠,分别使用地塞米松(A组)及环磷酰胺(B组)预处理后气道接种烟曲霉孢子建立IPA模型。观察小鼠存活率,肺病理检查,评估肺部及肺外脏器真菌负荷;支气管肺泡灌洗液(BALF)检测促炎、抗炎细胞因子浓度。结果 A组小鼠平均生存期与B组比较有显著差异。病理提示A组小鼠肺组织有大量炎症细胞聚集;B组可见到典型的曲霉菌丝浸润性生长。B组小鼠肺部烟曲霉CFU、烟曲霉18srRNA较A组升高;B组肺外各脏器与A组比较均具有统计学差异。检测BALF中炎症因子:A组TNF-α未检测到,IL-10峰值在72h出现,IL-1α自第一天起即升高,第3天达峰值;B组TNF-α及IL-10在24h后均明显升高,于48h达峰值;IL-1α一直在低水平维持;B组与各组间比较,TNF-α、IL-1α及IL-10均有显著差异。A、B两组IL-1β表达在接种烟曲霉后均迅速升高,并一直在高水平维持,两组间无差异。结论不同预处理造成小鼠免疫抑制后建立IPA模型,激素组肺部出现明显的炎症反应;环磷酰胺组可出现显著的全身真菌播散。     

PRMT6过表达在NF-κB/p65介导小鼠肺气肿炎症反应中的作用

[目的]观察蛋白精氨酸甲基转移酶6(PRMT6)过表达在NF-κB/p65介导小鼠肺气肿模型炎症反应中的作用及机制。[方法]80只Balb/c小鼠暴露于香烟烟雾建立肺气肿模型,随机分为阴性对照组、模型组、阳性对照组(空白慢病毒载体气管内滴注)和PRMT6过表达组(PRMT6慢病毒载体气管内滴注)各20只。HE法观察肺组织形态学,Western Blot测定肺组织PRMT6表达。ELISA测定肺泡灌洗液(BALF)和肺组织匀浆中肿瘤坏死因子-α(TNF-α)和白细胞介素-8(IL-8)水平。[结果]与阴性对照组比较,模型组和阳性对照组小鼠气道阻力、BALF和肺组织匀浆TNF-α及IL-8水平、肺组织NF-κB/p65表达均升高,动态肺顺应性、肺组织PRMT6相对表达量降低(P<0.05);与模型组和阳性对照组比较,PRMT6过表达组小鼠气道阻力、BALF和肺组织匀浆TNF-α及IL-8水平、肺组织NF-κB/p65表达降低,动态肺顺应性、肺组织PRMT6相对表达水平升高(P<0.05)。[结论]PRMT6过表达可能通过抑制肺气肿小鼠肺组织NF-κB/p65核转位,发挥抗炎作用,改善肺功能。     

RELMα可通过抑制PTEN信号通路来促进气道重塑并增加炎症反应

本研究旨在考察抵抗素样分子-α(resistin-like molecule-α,RELMα)在哮喘小鼠模型和小鼠肺上皮细胞中的表达及对气道重塑和炎症反应的影响。本研究通过卵清蛋白(ovalbumin,OVA)诱导小鼠哮喘模型,并评估了小鼠肺组织中RELMα、collagen I和fibronectin-1的表达。为了研究RELMα对PTEN信号通路的调控作用,本研究利用shRNA-RELMα、pcDNA3.0-RELMα和pcDNA3.0-PTEN转染小鼠肺上皮细胞系TC-1来上调或下调RELMα及PTEN的表达。通过Western blotting检测了TC-1细胞中RELMα、collagenⅠ、fibronectin-1、PTEN、TNF-α、IL-1β和IL-6的表达。研究发现,与对照小鼠相比,OVA致敏的哮喘小鼠的肺组织中RELMα、collagen I和fibronectin-1的表达显著升高。上调RELMα可显著升高collagenⅠ、fibronectin-1、TNF-α、IL-1β和IL-6的表达并抑制PTEN信号通路的活化。上调PTEN则可抑制collagenⅠ、fibronectin-1、TNF-α、IL-1β和IL-6的表达。本研究表明,RELMα在哮喘发病过程中高表达,上调RELMα可抑制PTEN信号通路来促进气道重塑并增加炎症反应。     

H9N2亚型猪流感病毒诱导小鼠急性肺损伤中TNF-α、IL-1β、IL-6和IL-10的变化和作用

目的探讨H9N2亚型猪流感病毒诱导小鼠急性肺损伤过程中炎症因子的变化和作用。方法通过滴鼻的方法将H9N2亚型猪流感病毒感染BALB/c小鼠,于感染后2、4、6、10、14 d取小鼠肺组织匀浆,分别测定肺组织匀浆中TNF-α、IL-1β、IL-6和IL-10的浓度。结果实验组肺组织匀浆中TNF-α、IL-1β、IL-6和IL-10在不同时间点浓度均显著高于正常对照组(P<0.05),TNF-α和IL-1β于14 d后趋于正常,而IL-6和IL-10增高持续至14d后。结论 H9N2猪流感病毒诱导小鼠急性肺损伤过程中炎症因子发挥重大作用,TNF-α和IL-1β起致炎作用,IL-6可能和IL-10一样,发挥抗炎作用。     

莲心碱对LPS诱导小鼠急性肺损伤的保护作用

目的探讨莲心碱对脂多糖(lipopolysaccharide,LPS)诱导的小鼠急性肺损伤(ALI)的作用。方法BALB/c小鼠随机分为对照组、LPS组、LPS+莲心碱(2、4、8 mg/kg)组、地塞米松(5 mg/kg)组,鼻腔滴入法建立LPS诱导的急性肺损伤模型。12 h后,组织学观察肺组织的病理学变化;ELISA检测肺泡灌洗液(BALF)中TNF-α、IL-6和IL-1β的含量;Wright-Giemsa染色检测BALF中中性粒细胞数;BCA法检测总蛋白含量;Evans blue检测肺毛细血管通透性;分光光度法检测肺匀浆上清中MPO的活性、MDA的含量、SOD的活性、GSH的含量;流式细胞术检测肺组织中ROS的含量。结果 LPS组可见肺组织具有炎性细胞浸润、支气管肺泡壁增厚和肺充血现象,而莲心碱组可以改善肺损伤情况;LPS组BALF中TNF-α、IL-6、IL-1β的含量明显增加、中性粒细胞数和总蛋白量显著增多,肺毛细血管通透性、MPO活性和MDA含量增加,SOD活性和GSH含量降低,ROS含量增加,而莲心碱组能够降低BALF中TNF-α、IL-6、IL-1β的含量,减少中性粒细胞数和总蛋白量,降低肺毛细血管通透性,降低MPO活性和MDA含量,增加SOD活性和GSH含量,降低ROS的含量。结论莲心碱可通过抗炎抗氧化作用保护LPS诱导的小鼠急性肺损伤。     

抗生素诱导的呼吸道菌群缺失对小鼠RSV感染的影响

目的探究抗生素雾化暴露引起的呼吸道菌群缺失对小鼠呼吸道合胞病毒(RSV)感染的影响,为临床合理使用抗生素提供指导意见。方法32只BALB/c小鼠分为2组:雾化ddH₂O对照组和雾化ABX组合抗生素组,处理6 d后,进行细菌16S rRNA基因PCR检测,构建呼吸道菌群缺失小鼠模型。上述2组组内再随机分为2小组,即PBS对照组(ddH₂O+PBS,ABX+PBS)和RSV感染组(ddH₂O+RSV,ABX+RSV),饲养至第14天。检测和分析各组小鼠支气管肺泡灌洗液(BALF)中的炎症细胞和相关细胞因子(TNF-α、IL-8、IL-10及MCP-1)的数量和水平,观察肺组织病理学状况及检测病毒载量。结果BALF中细菌DNA提取和16S rRNA基因PCR检测显示,雾化ABX组合抗生素处理能够有效地剔除呼吸道菌群。BALF中炎症细胞和相关细胞因子检测显示,ABX+RSV组炎症细胞总数明显增多(P<0.05),分类以巨噬细胞和淋巴细胞为主;且细胞因子TNF-α、IL-8、MCP-1及IL-10水平显著升高(均P<0.05)。肺部HE染色显示,感染RSV后ddH₂O+RSV组和ABX+RSV组小鼠肺部损伤明显加重(均P≤0.01),与ddH₂O+RSV组相比较,ABX+RSV组的病毒载量明显升高(t=2.7160,P=0.0217)。结论雾化ABX组合抗生素不仅能够有效地剔除呼吸道菌群,而且明显增加了小鼠感染RSV的风险,导致呼吸道炎症加重,以及病毒载量升高。     

布地奈德混悬液对哮喘模型小鼠肺组织TLR4/MyD88/NF-κB通路的影响

摘要 目的：探究布地奈德混悬液对哮喘模型小鼠肺组织TOLL样受体4（toll-like receptor 4,TLR4）/髓样分化因子88（myeloid differentiation factor 88,MyD88）/核因子κB（nuclear factor-κB,NF-κB）通路的影响。方法：使用4 %鸡蛋清白蛋白与2 %的Al（OH3）共同致敏小鼠,建立咳嗽变异性哮喘小鼠模型40只,将模型大鼠分别使用低、中、高剂量（0.2、1.0、2.0 g/kg）布地奈德混悬液和孟鲁司特钠进行干预,1次/日连续干预14 d,于干预14 d时采集小鼠的支气管肺泡灌注液（bronchoalveolar lavage fluid,BALF）、气管及肺组织,对各组BALF中的白细胞（white blood cell,WBC）、嗜酸性粒细胞、血清γ干扰素（interferon-γ,IFN-γ）、白细胞介素-1β（interleukin-1β,Il-1β）、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平差异开展比较,对各组小鼠肺组织黏膜上皮增生程度评分、炎症细胞浸润程度评分、病变总评分差异,以及TLR4、MyD88、p65蛋白表达差异进行分析。结果：分析显示,布地奈德混悬液能够显著降低哮喘模型小鼠BALF中白细胞及嗜酸性粒细胞数量,同时还能够改善小鼠气管和支气管黏膜上皮增生与肺组织炎症细胞浸润状态,且干预后小鼠肺组织中的TLR4、MyD88、p65蛋白表达水平出现了明显的降低。结论：布地奈德混悬液对改善小鼠哮喘效果较好,其作用机制可能与该药能够调节TLR4、MyD88、p65蛋白表达,进而影响炎症和免疫反应进程有关。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.