人白细胞介素12表达质粒与Mtb8.4基因疫苗 联合免疫增强对小鼠结核杆菌感染的免疫保护效果

本课题旨在研究结核分枝杆菌Mtb8.4基因疫苗与人白细胞介素12（hIL-12）联合免疫小鼠所诱导的细胞免疫应答及对小鼠结核杆菌感染的免疫保护效果。40只C57BL/6N小鼠随机分为Mtb8.4基因疫苗＋hIL-12质粒组（联合免疫组）、Mtb8.4基因疫苗组、卡介苗（BCG）组、空载体组和PBS组,基因疫苗、空载体和PBS,经肌内注射法免疫各组小鼠,每隔3周免疫1次,共免疫3次,BCG组经尾部皮下注射1×106 CFU BCG免疫1次。免疫4周后,每组处死3只小鼠,采用酶联免疫吸附法（ELISA）检测脾细胞培养上清中细胞因子水平;乳酸脱氢酶（LDH）释放法检测细胞毒性T细胞（CTL）杀伤活性。每组其余5只小鼠用结核杆菌H37Rv强毒株经尾静脉攻击,4周后,计数肺和脾组织中的结核杆菌菌落数,对小鼠部分肺和脾组织作病理切片,HE染色观察组织病变程度,Z-N染色查抗酸杆菌,观察该疫苗对小鼠结核杆菌感染的免疫保护效果。结果显示,联合免疫组能诱导较强的抗原特异性Th1型细胞免疫应答,免疫小鼠脾细胞培养上清液IFN-γ和IL-2水平（分别为1493.34±8.128pg/mL、747.489±48.676pg/mL）,显著高于Mtb8.4基因疫苗组,与BCG组相当,IL-4分泌减少,特异性CTL杀伤活性增强,对小鼠结核杆菌感染有较好的免疫保护效果,使小鼠肺和脾组织中的结核杆菌菌落数显著减少,组织病变明显减轻,其效果与卡介苗（BCG）组相当,优于Mtb8.4基因疫苗组。表明hIL-12表达质粒与Mtb8.4基因疫苗联合免疫后,能够增强Mtb8.4基因疫苗所诱导的细胞免疫应答,使Mtb8.4基因疫苗的免疫效力得到很大提高。     

结核杆菌Ag85B基因疫苗的免疫保护效果研究

为研究结核杆菌Ag85B基因疫苗的免疫原性和免疫保护效果,将雌性C57BL/6N小鼠32只,随机分为4组,即结核杆菌Ag85B基因疫苗组、BCG组、pcDNA3.1( )组和PBS组.取各免疫组小鼠脾细胞培养上清检测细胞因子水平;同时进行CTL杀伤活性检测;进一步用结核杆菌H37Rv国际标准强毒株静脉注射攻击小鼠,计数肺和脾组织中的结核杆菌菌落数,对小鼠部分肺和脾组织作病理切片,HE染色观察组织病变程度,Z-N染色检查抗酸杆菌,观察该疫苗对小鼠结核杆菌感染的免疫保护效果.结果表明,结核杆菌Ag85B基因疫苗对小鼠结核杆菌感染有一定的免疫保护效果,能够诱导较强的抗原特异性Th1型细胞免疫应答,细胞因子IFN-γ和IL-1分泌增加,IL-4分泌减少,CTL特异性活性增加;使小鼠肺和脾组织中的结核杆菌菌落数较空载体组显著减少,组织病变明显减轻.     

DNA疫苗初免-BCG加强免疫法提高小鼠抗结核分枝杆菌感染效率的研究

对结核分枝杆菌DNA四价疫苗(编码Ag85B,MPT64,MPT70和TB10.4抗原)初发免疫、卡介苗(BCG)加强免疫后小鼠产生免疫应答的能力和抗结核杆菌感染效率进行了分析.攻毒后细菌计数结果显示,DNA初免、BCG加强组肺脏和脾脏载菌数的对数值比阴性对照组下降1.0～1.3(P<0.01),且显著低于DNA四价苗和BCG组(P<0.05).3次免疫后,BCG加强组外周血中CD4 和CD8 T淋巴细胞显著增多(P<0.05);经4种抗原分别刺激,BCG加强组脾细胞产生的抗原特异性IFN-γ和IL-2水平显著高于其他免疫组,其中Ag85B抗原诱导产生的IFN-γ浓度为1250ng/L,IL-2浓度为230ng/L,分别是DNA四价苗组的1.6,1.7倍(P<0.05),是BCG组PPD诱导产生相应细胞因子浓度的2.6倍和2.2倍(P<0.05);此外,BCG加强组肺脏中分泌穿孔素的淋巴细胞数量也显著增加(P<0.05).结果表明,DNA初发免疫、BCG加强免疫法能显著提高小鼠CD4 ,CD8 T细胞介导的免疫应答,增强小鼠抗结核杆菌感染能力,是提高结核病疫苗免疫效果的新途径.     

汉坦病毒核蛋白基因疫苗的初步研究

探讨了汉坦病毒核蛋白(NP)S基因疫苗的免疫效果。构建重组真核表达质粒pcDNA3.1 S,直接肌注免疫BALB/c小鼠,分别用ELISA法检测血清特异性抗体的变化,MTT法检测T细胞增殖反应,以及用ELISAkit检测免疫鼠脾细胞上清液中细胞因子IL-4和IFN-γ的动态变化,从而了解免疫鼠的体液免疫反应和细胞免疫反应。pcDNA3.1 S接种组的小鼠血清抗体水平、T细胞增殖反应以及细胞因子IL-4和IFN-γ的产生水平均较对照组pcDNA3.1 空载体接种组的要高。编码核蛋白的S基因的核酸免疫可同时启动机体的细胞免疫和体液免疫反应,S基因是汉坦病毒核酸疫苗的一个比较理想的侯选抗原基因。     

Arrb1基因敲除对小鼠T淋巴细胞发育的影响

该文旨在研究Arrb1(β-arrestin1)基因敲除对小鼠T细胞发育的影响,进一步探讨急性T淋巴细胞白血病(T-cell acute lymphocytic leukemia,T-ALL)发病机制。该文使用q-PCR、Western blot分别检测Arrb1基因敲除的C57BL/6J小鼠中Arrb1的m RNA和蛋白质水平;流式细胞术检测Arrb1基因敲除小鼠及野生型小鼠的胸腺、外周血、淋巴结的T细胞比例。结果显示,与野生型相比,Arrb1基因敲除小鼠的胸腺CD4CD8双阴(double negative,DN)细胞比例明显增加,DN1期细胞比例增加最为显著(P0.05),而DN4期细胞比例减少(P0.05);CD4CD8双阳(double positive,DP)细胞比例显著减少(P0.05)。外周血CD4阳性T细胞比例减少(P0.05),淋巴结CD4阳性T细胞比例以及CD4/CD8阳性T细胞比值减少(P0.05)。研究结果证明,Arrb1基因敲除显著影响小鼠T细胞发育,使T细胞发育阻滞在DN期,从而可能成为影响T-ALL发病的重要因素。     

Ipr1/PPE68重组BCG诱导BALB/C小鼠免疫应答的探讨

目的构建Ipr1/PPE68重组卡介苗(Recombinant BCG,rBCG),探讨其诱导BALB/C小鼠免疫应答的效果。方法将Ipr1和PPE68基因及结核分枝杆菌(mycobacterium tuberculosis,MTB)复制子OriM分别插入pBudCE4.1的多克隆位点,构建共表达穿梭质粒pBIPO,将其电转入BCG,构建Ipr1/PPE68-rBCG并将rBCG免疫BALB/C小鼠,检测小鼠血清中IgG2a、IL-12、IFN-γ及IL-4的水平、特异性脾淋巴细胞增殖和CD4+和CD8+T细胞数量,同时观察脾、肺荷菌量及脾、肺组织病理学变化。结果酶切测序及菌落PCR鉴定Ipr1和PPE68以及OriM基因序列与理论值相符,Western-blotting结果显示Ipr1和PPE68蛋白成功表达。Ipr1/PPE68-rBCG免疫小鼠后,血清中的IgG2a和IL-12水平及脾淋巴细胞增殖情况明显高于对照组,但与BCG组相比没有显著意义;IFN-γ水平显著低于BCG组,与对照组相比无显著性差异;各组别IL-4的水平差异均不明显。脾、肺荷菌实验未见菌落生长,肺、脾组织未见病理学改变。结论成功构建Ipr1/PPE68-rBCG,该重组BCG能诱导BALB/C小鼠的细胞免疫应答。     

受体相互作用蛋白激酶-3参与甲型H1N1流感病毒感染小鼠记忆性CD8＋ T细胞的应答

受体相互作用蛋白激酶-3(receptor-interacting protein kinase 3, RIPK3)是坏死复合体的关键成分之一,介导细胞程序性死亡(programmed cell death,PCD)的发生。前期研究发现流感抗原特异性CD8^＋T细胞的初次应答部分依赖于RIPK3分子,为探讨其在记忆性CD8^＋T细胞应答中的作用,对初次感染后的C57BL/6小鼠在免疫记忆阶段进行了再次感染,并用流式细胞仪检测了流感病毒特异性的记忆性CD8^＋T细胞的表型和功能。结果发现小鼠初次感染甲型 H1N1流感病毒株A/Puerto Rico/8/34后37 d, RIPK3敲除小鼠的CD8^＋T细胞比例及分泌细胞因子γ-干扰素(IFN-γ)和肿瘤坏死因子-α(TNF-α)的能力均显著低于野生型小鼠;在再次感染相同病毒时,RIPK3敲除小鼠流感病毒特异性CD8^＋T细胞比例及分泌细胞因子IFN-γ的能力依旧显著低于野生型小鼠;而CD8^＋中枢型记忆性T细胞(TCM)比例显著高于野生型小鼠,效应型记忆性T细胞(TEM)或效应性T细胞(TEff)比例却显著低于野生型小鼠。提示RIPK3分子参与调节流感病毒特异的记忆性CD8^＋T细胞诱生数量和分泌细胞因子功能,并影响其TCM与TEM/TEff的比例,为深入探索病毒特异的记忆性CD8^＋T细胞应答的分子机制提供了新线索。     

共表达结核杆菌Ag85A-ESAT-6融合抗原与IL-21核酸疫苗的构建及免疫效果研究

目的：构建结核杆菌Ag85A-ESAT-6融合抗原与细胞因子IL-21共表达核酸疫苗pIRES-IL-21-Ag85A-ESAT-6,研究其对小鼠免疫功能的影响。方法：用PCR方法分别扩增出Ag85A和IL-21编码基因,并先后插入质粒pIRES-ESAT-6中,构成共表达核酸疫苗pIRES-IL-21-Ag85A-ESAT-6;免疫小鼠后,通过CTL和NK细胞杀伤活性和脾细胞增殖试验,以及小鼠血清抗体、IFN-γ和IL-4的检测,评价该核酸疫苗的免疫效果。结果：pIRES-IL-21-Ag85A-ESAT-6核酸疫苗免疫鼠的CTL活性、脾细胞增殖反应、IFN-γ水平及血清抗体产生明显高于对照组,差异有显著性意义。结论：pIRES-IL-21-Ag85A-ESAT-6核酸疫苗能够诱导小鼠产生有效的免疫反应,可作为新型结核疫苗的候选组分。     

人工合成胸腺肽α1对正常小鼠和免疫抑制荷瘤小鼠的免疫调节作用

目的:本研究通过对正常小鼠和免疫抑制荷瘤小鼠皮下注射人工合成胸腺肽α1 (sTα1).方法:检测各组小鼠淋巴细胞亚群比率、T淋巴细胞增殖数量和脾细胞细胞因子的表达水平三个指标,来判定sTα1对小鼠免疫功能的影响.结果:sTα1可提高小鼠外周血CD4+T细胞比率、降低CD8+T细胞比率,使CD4+/CD8+的T细胞比率增加.sTα1能明显加强正常小鼠、环丙酰胺(CTX)免疫抑制小鼠和荷瘤+CTX免疫抑制小鼠的脾淋巴细胞的增殖(P＜0.5),明显促进正常小鼠及各免疫抑制组小鼠脾细胞细胞因子mIL-2和mIFNγ释放(P＜0.5).结论:sTα1可促进T细胞的快速成熟,活化T细胞,纠正了荷瘤和化疗药物产生的免疫抑制作用,有效刺激免疫系统,促进Th1型细胞免疫反应.     

IL－7可降低小鼠纤维肉瘤转化生长因子β1的表达

ＩＬ－７可降低小鼠纤维肉瘤转化生长因子β１的表达细胞因子基因所编码的蛋白质可调节免疫反应。导入细胞因子基因修饰肿瘤细胞可增强宿主免疫反应。ＩＬ－７基因导入可增加机体对肿瘤细胞的免疫反应,使肿瘤消退。转化生长因子臼（ＴＧＦ－β１）是许多细胞产生的一种免...     

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.     

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     

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.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

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.     

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).     

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.