Immune Responses in Wild-type Mice Against Prion Proteins Induced Using a DNA Prime-Protein Boost Strategy

Objective To break immune tolerance to prion （PrP） proteins using DNA vaccines.Methods Four different human prion DNA vaccine candidates were constructed based on the pcDNA3.1 vector：PrP‐WT expressing wild‐type PrP,Ubiq‐PrP expressing PrP fused to ubiquitin,PrP‐LII expressing PrP fused to the lysosomal integral membrane protein type II lysosome‐targeting signal,and PrP‐ER expressing PrP locating the ER.Using a prime‐boost strategy,three‐doses of DNA vaccine were injected intramuscularly into Balb/c mice,followed by two doses of PrP protein.Two weeks after the last immunization,sera and spleens were collected and PrP‐specific humoral and cellular immune responses evaluated by ELISA and ELISPOT tests.Results Higher levels of serum PrP antibodies were detected in mice vaccinated using the strategy of DNA priming followed by protein boosting.Of these,WT‐PrP,Ubiq‐PrP,and PrP‐LII induced significantly higher humoral responses.ELISPOT tests showed markedly increased numbers of IFN‐γ‐secreting T cells in mice vaccinated using the strategy of DNA priming followed by protein boosting after stimulation with recombinant PrP23‐90 and PrP23‐231.PrP‐ER inducedthe strongest T‐cell response.Conclusion Prion vaccines can break tolerance to PrP proteins and induce PrP‐specific humoral and cellular immune responses.

Study on the molecular mechanism of Osmanthus fragrans Lour.on boosting immunity based on network pharmacology and molecular docking

Objective:To explore the molecular mechanism of Osmanthus Fragrans Lour.(OFL)in enhancing immunity.Methods:The compounds and action targets of OFL were collected from the Traditional Chinese Medicine Systematic Pharmacology Database and Analysis Platform.Protein targets of compounds were obtained from the UniProt database and relevant targets of boosting immunity were retrieved from the Genecards database.The Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and Gene Ontology function enrichment analysis were performed through the DAVID analysis website,Visualization and Integrated Discovery.Finally,the results of the network analysis were validated by performing molecular docking using AutoDock vina.Results:A total of 7 active compounds and 167 potential active targets were identified in OFL.A total of 1549 genes with a correlation score of≥1 were retrieved from the Genecards website with the keyword“boost immunity”,and 107 genes were obtained by crossing the 167 genes of OFL with the 1549 genes of boosting immunity.A total of 4802 entries were obtained from Gene Ontology functional enrichment(P<0.05).A total of 234 signaling pathways were obtained through a Kyoto Encyclopedia of Genes and Genomes pathway analysis(P<0.05).Tumor necrosis factor(TNF)and interleukin 17(IL-17)signaling pathways were closely related to body immunity.The molecular docking results showed that all the core compounds in OFL the characteristics including low energy,a stable structure and high binding activity when bound to IL-17 and TNF-αprotein.Kaempferol showed the highest affinity with IL-17,and fucosterol showed the highest affinity with TNF-α.Conclusions:Through studies on network pharmacology and molecular docking,we have further demonstrated that OFL could enhance the immunity of the body through multi-component,multi-target and multi-pathway actions,and that IL-17/TNF-αsignalling pathway is the key molecular mechanism.

Flt3L及CCL5对prime/boost免疫策略中抗原特异性免疫应答的增强及抗肿瘤作用

目的:研究Flt3L与CCL5作为联合佐剂在prime/boost免疫策略中对HBc抗原特异性免疫应答的增强及抗肿瘤作用。方法:将两种细胞因子质粒与携带HBc抗原的DNA疫苗经肌内注射法共免疫小鼠,免疫3次后再用原核表达的HBc颗粒蛋白或HBcDNA疫苗加强,观察对稳定表达HBcAg的小鼠黑色素瘤细胞(B16-HBc)的生长抑制作用;并分别采用MTT法检测荷瘤小鼠脾淋巴细胞增殖、流式细胞术检测脾CD8+T淋巴细胞中IFN-γ表达、ELISA法检测脾淋巴细胞培养上清IL-2、IL-4含量及乳酸脱氢酶(LDH)释放法检测特异性CTL杀伤活性。结果:与对照组相比,佐剂联合DNA疫苗免疫经蛋白加强组(DDP/Adj)显著抑制肿瘤生长;佐剂联合DNA疫苗免疫组(DDD/Adj)及DDP/Adj组均可促进特异性淋巴细胞增殖反应(P<0.05),且DDP/Adj高于DDD/Adj组(P<0.05);DDD/Adj及DDP/Adj组小鼠脾脏CD8+T淋巴细胞中IFN-γ表达、IL-2表达水平及CTL杀靶活性均高于对照组(P<0.01或P<0.05),IL-4表达水平在各组无显著区别(P>0.05)。结论:在prime/boost免疫策略中,采用Flt3L与CCL5两种细胞因子联合应用可显著促进荷瘤小鼠产生抗原特异性免疫应答及抗肿瘤作用。

DNA vaccine prime and replicating vaccinia vaccine boost induce robust humoral and cellular immune responses against MERS-CoV in mice

As of December 2022,2603 laboratory-identified Middle East respiratory syndrome coronavirus(MERS-CoV)infections and 935 associated deaths,with a mortality rate of 36%,had been reported to the World Health Organization(WHO).However,there are still no vaccines for MERS-CoV,which makes the prevention and control of MERS-CoV difficult.In this study,we generated two DNA vaccine candidates by integrating MERS-CoV Spike(S)gene into a replicating Vaccinia Tian Tan(VTT)vector.Compared to homologous immunization with either vaccine,mice immunized with DNA vaccine prime and VTT vaccine boost exhibited much stronger and durable humoral and cellular immune responses.The immunized mice produced robust binding antibodies and broad neutralizing antibodies against the EMC2012,England1 and KNIH strains of MERS-CoV.Prime-Boost immunization also induced strong MERS-S specific T cells responses,with high memory and poly-functional(CD107a-IFN-γ-TNF-α)effector CD8t T cells.In conclusion,the research demonstrated that DNA-Prime/VTT-Boost strategy could elicit robust and balanced humoral and cellular immune responses against MERS-CoV-S.This study not only provides a promising set of MERS-CoV vaccine candidates,but also proposes a heterologous sequential immunization strategy worthy of further development.

基于Prime-Boost免疫策略的猪附红细胞体eno基因免疫效果评价

为了评估猪附红细胞体eno基因核酸疫苗与重组腺病毒疫苗采用Prime-Boost免疫策略对小鼠的免疫效果,本研究应用pVAX1-eno核酸疫苗和Ad5-M/eno重组腺病毒疫苗免疫接种小鼠,将20只BALB/c小鼠随机分为4组:Prime-Boost策略组、Ad5-M/eno重组腺病毒疫苗组、pVAX1-eno核酸疫苗组及PBS对照组。通过ELISA检测方法分别测定血清中抗猪附红细胞体特异性抗体、IgG_(1)、IgG_(2a)抗体水平及IFN-γ、IL-4细胞因子水平,三免后测定小鼠脾脏细胞中CD4^(+)、CD8^(+)的含量,对试验数据进行统计分析。结果显示,Prime-Boost策略组接种的小鼠血清中抗猪附红细胞体特异性抗体、IgG_(1)、IgG_(2a)抗体水平均显著高于Ad5-M/eno重组腺病毒疫苗组(P<0.05),极显著高于pVAX1-eno核酸疫苗组(P<0.01);Prime-Boost策略组的IL-4与IFN-γ细胞因子水平、CD4^(+)与CD8^(+)水平显著高于Ad5-M/eno疫苗组和pVAX1-eno核酸疫苗组(P<0.05)。试验结果表明,与猪附红细胞体Ad5-M/eno,PVAX1-eno单疫苗相比,采用Prime-Boost免疫策略更能显著提高小鼠体液免疫水平与细胞免疫水平。

PEI增强G250 DNA疫苗和重组肽疫苗的prime-boost免疫策略研究

目的 :探讨PEI作为免疫佐剂对G250抗原肽基因PVAX1/C-G250肽-C免疫保护效果的增强作用及联合应用CAIX蛋白疫苗进行PRIME—BOOST免疫程序免疫增强效果。方法:用Eco R I、Xho I和Eco R I、Sal I分别双酶切PVAX1及既往构建的p ET28a(+)/C-G250肽-C质粒。利用DNA重组技术构建重组质粒PVAX1/C-G250肽-C,酶切分析鉴定。大量提取质粒并分光光度计测质粒含量。将32只雌性昆明小鼠随机分为(A)裸DNA组,(B)DNA-PEI复合物组,(C)DNA-PEI+蛋白疫苗组,(D)空白对照组。按0,10,20,30天程序经股四头肌注射免疫。C组在第20天及第30天进行蛋白冲击。初次免疫前和第40天鼠尾取血,ELISA法检测抗体滴度。流式细胞术测淋巴细胞亚群CD4+和CD8+。结果:酶切及基因测序鉴定证实G250抗原肽c DNA正确插入PVAX1/C-G250肽-C真核表达的重组质粒中。昆明小鼠经4次免疫后,3个实验组都产生了特异性的体液和细胞免疫反应,B组的抗体滴度1:1.28×104及CD4+、CD8+达26.12%和12.60%,明显高于A组的1:3.2×103和CD4+,CD8+占到19.32%和10.74%。而蛋白冲击组的1:5.12×104和CD4+,CD8+占到41.96%和15.14%,明显高于B组(P>0.05)。结论:成功构建重组质粒PVAX1/C-G250肽-C。该DNA疫苗与PEI和G250蛋白疫苗联合使用后产生极强的免疫原性,诱导产生了高滴度、高特异性抗体及细胞免疫反应。证实G250DNA疫苗联合PEI使用并进行蛋白疫苗冲击的免疫策略可产生强大的免疫保护作用。为恶性肿瘤的术后辅助治疗提供新的思路和方法。

Anthraquinone Derivatives as an Immune Booster and their Therapeutic Option Against COVID-19

Anthraquinone derivatives are identified for their immune-boosting,anti-inflammatory,and anti-viral efficacy.Hence,the pre-sent study aimed to investigate the reported anthraquinone derivatives as immune booster molecules in COVID-19 infection and evaluate their binding affinity with three reported targets of novel coronavirus i.e.3C-like protease,papain-like protease,and spike protein.The reported anthraquinone derivatives were retrieved from an open-source database and filtered based on a positive druglikeness score.Compounds with positive druglikeness scores were predicted for their targets using DIGEP-Pred and the interaction among modulated proteins was evaluated using STRING.Further,the associated pathways were recorded concerning the Kyoto Encyclopedia of Genes and Genomes pathway database.Finally,the docking was performed using autodock4 to identify the binding efficacy of anthraquinone derivatives with 3C-like protease,papain-like protease,and spike protein.After docking the pose of ligand scoring minimum binding energy was chosen to visualize the ligand-protein interaction.Among 101 bioactives,36 scored positive druglikeness score and regulated multiple pathways concerned with immune modulation and(non-)infectious diseases.Similarly,docking study revealed torososide B to possess the highest binding affinity with papain-like protease and 3C-like protease and 1,3,6-trihydroxy-2-methyl-9,10-anthraquinone-3-O-(6′-O-acetyl)-β-d-xylopyranosyl-(1→2)-β-d-glucopyranoside with spike protein.

棘皮动物弧菌诱导中间球海胆免疫致敏现象分析

为探究中间球海胆(Strongylocentrotus intermedius)是否存在免疫致敏现象,使用棘皮动物弧菌(Vibrio echinoideorum)对中间球海胆进行重复感染(首次、二次菌浓度分别为10^(3)、10^(4) CFU/mL),检测并比较了两次注射感染后不同时间点中间球海胆体腔细胞密度、吞噬能力、酸性磷酸酶(ACP)活力、活性氧(ROS)含量、总抗氧化能力(T-AOC)等相关免疫指标的变化,以及二次感染后免疫致敏组和对照组间成活率的差异。结果表明:与首次感染相比,二次感染时诱导致敏组的体腔细胞总密度、吞噬细胞密度、ACP、ROS和T-AOC等均出现显著上升(P<0.05),且响应时间明显缩短,达到峰值的时间分别提前了36、36、84、12、36 h,且各指标的峰值均显著高于首次感染(P<0.05);二次感染后,诱导致敏组在6 h时的吞噬率(45.41%±6.39%)显著高于对照组(33.17%±1.94%);经过棘皮动物弧菌低浓度诱导后,诱导致敏组存活率(43.33%±10.00%)显著高于未经诱导的阳性对照组(7.78%±10.71%)(P<0.05)。研究表明,低浓度棘皮动物弧菌能诱导中间球海胆产生免疫致敏现象,此结果可为中间球海胆的疾病防控提供新思路。

全程局部同步推量调强放疗对局部晚期食管癌患者的影响

目的:探讨全程局部同步推量调强放疗(SIB-IMRT)对局部晚期食管癌患者的影响。方法:选取2021年4月—2023年4月蚌埠医学院第一附属医院收治的100例局部晚期食管癌患者。随机将其分为观察组和对照组,各50例。两组均给予紫杉醇联合顺铂化疗,对照组采用常规调强放疗(C-IMRT),观察组采用SIB-IMRT。比较两组临床疗效,治疗前后肿瘤指标、免疫功能及不良反应。结果:观察组总有效率为88.00%,明显高于对照组的70.00%,差异有统计学意义(P<0.05)。治疗后,两组细胞角蛋白19片段(CYFRA21-1)、鳞状细胞癌抗原(SCC)、癌胚抗原(CEA)水平均降低,观察组CYFRA21-1、SCC、CEA水平均低于对照组,差异有统计学意义(P<0.05)。治疗后,两组CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)均降低,CD8^(+)均升高,但观察组CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)均高于对照组,CD8^(+)低于对照组,差异有统计学意义(P<0.05)。观察组放射性食管炎、放射性气管炎、骨髓抑制、胃肠道反应发生率均低于对照组,差异有统计学意义(P<0.05)。结论:SIBIMRT治疗局部晚期食管癌患者的效果更好,不仅能够降低血清肿瘤指标的表达,减轻放化疗对免疫功能带来的影响,还能减少不良反应的发生。

中药多糖的提取及其在畜禽养殖应用研究进展

中药多糖在中药材中普遍存在,是从中药材中提取出的高分子化合物。中药多糖对畜禽具有促生长、提高免疫力和抗氧化的功能,在禽类、生猪和反刍类动物养殖中应用广泛。本文对中药多糖的提取方式和在畜禽养殖中的应用进行综述,对其应用前景进行展望,为其应用研究提供依据。

Immune Priming Induced by Heat-inactivated White Spot Syndrome Virus (WSSV) in Fenneropenaeus chinensis Cultured at Different Temperature

[ Objective] This study was designed to explore whether heat-inactivated white spot syndrome virus （ WSSV ） could induce immune priming in Fenneropenaeus chinensis. [Method] Shrimps cultured at 15 （group E15℃ ）, 23 （group E23℃ ）, 28 （group E28℃ ） and 32 （group E32℃ ）℃ were fed for six successive days with the meat of WSSV-infected shrimps, which had been treated at 60℃ for 1 h. Meanwhile, the shrimps of positive control were fed with a diet containing active WSSV at 23℃ （ group C23℃ ）, and the shrimps of negative control were fed with commercial compound feed only at 23℃ （ group CF23℃ ）. On Day 13 of the experiment, the survivors were re-challenged with active WSSV, and then the survival time, survival rate, mortality rate and viral load in each group were measured. The results showed that no death occurred among the shrimps fed with a diet containing heat-inactivated WSSV before the secondary challenge, while all the shrimps fed with a diet containing active WSSV （ group CF23℃ ） died, suggesting that WSSV was completely inactivated by treatment at 60℃ for 1 h. On day 19 of the experiment, the survival rate in groups E15℃ , E23℃, E28℃, E32℃ and CF23℃ was 80.41% , 33.29%, 8.47% , 16.43% and 8.89%, respectively. There was an extremely significant difference in survival rate between group E15℃ and other groups （ P 〈 0.01 ）, a significant difference in survival rate between group E23℃ and CF23℃ , E28℃, E32℃ （P 〈 0. 05）, and no significant difference in survival rate between groups E28℃ and E32℃ （ P 〉 0. 05 ）. RT-qPCR revealed WSSV replicated most rapidly at 28℃ after the secondary challenge, while high （32℃） and low （ 15℃ ） temperature inhibited the multiplication of WSSV. In summary, heat-inactivated WSSV can induce immune priming response and provide some protection to shrimps against WSSV infection. The multiplication rate of WSSV is closely related to water temperature.

猪支原体肺炎活疫苗与灭活疫苗联合免疫效果评价

为探寻一种更加合理高效的猪支原体肺炎(MPS)免疫方式,本研究使用MPS弱毒疫苗进行基础免疫后14 d再使用灭活疫苗进行加强免疫,通过人工感染猪肺炎支原体来评价其免疫效果。同时将这种免疫程序在规模化猪场进行应用,通过计算一定时期内的日增重来评价其免疫效果。结果显示:联合免疫在保证黏膜免疫效果的同时并未降低体液免疫水平;更为重要的是,联合免疫不但具备较高攻毒保护率,而且在攻毒后剖杀时其肺泡灌洗液中抗原含量远低于其他免疫方式。以上结果表明,联合免疫可以产生较好的免疫协同作用,从而提高了机体的综合免疫保护能力。田间试验结果发现:联合免疫组猪群从21日龄至80日龄平均增重27.31 kg,比活疫苗免疫组猪群多增重3.02 kg,比灭活疫苗免疫组猪群多增重3.73 kg;其平均日增重可达0.46 kg/d。本研究为防治猪支原体肺炎提供了新的思路。

全程局部同步推量调强放疗治疗局部晚期食管癌的效果及对3年生存率的影响

目的探讨全程局部同步推量调强放疗(SIB-IMRT)治疗局部晚期食管癌的效果及对3年生存率的影响。方法回顾性分析2018年8月—2019年6月收治的局部晚期食管癌108例的临床资料,根据治疗方法分为研究组和对照组各54例,研究组采用SIB-IMRT治疗,对照组采用序贯加量调强放疗(IMRT)治疗,比较2组临床疗效、糖类抗原125(CA125)、癌胚抗原(CEA)、细胞角化素蛋白片段19(CYFRA21-1)、免疫功能[CD3+、CD4+、CD8+和CD4+/CD8+]、3年生存率。结果2组近期客观缓解率比较差异无统计学意义(P>0.05)。治疗后研究组CA125、CEA、CYFRA21-1和CD8+水平低于对照组、CD3+、CD4+、CD4+/CD8+高于对照组(P<0.05,P<0.01)。研究组3年生存率高于对照组,放射性食管炎和放射性肺炎发生率低于对照组(P<0.05)。结论SIB-IMRT治疗局部晚期食管癌可显著降低血清肿瘤标志物水平和放射性肺炎发生率,减少对免疫功能的影响,提高远期生存率。

Integer Factorization of Semi-Primes Based on Analysis of a Sequence of Modular Elliptic Equations

In this paper is demonstrated a method for reduction of integer factorization problem to an analysis of a sequence of modular elliptic equations. As a result, the paper provides a non-deterministic algorithm that computes a factor of a semi-prime integer n=pq, where prime factors p and q are unknown. The proposed algorithm is based on counting points on a sequence of at least four elliptic curves y2=x(x2+b2)(modn) , where b is a control parameter. Although in the worst case, for some n the number of required values of parameter b that must be considered (the number of basic steps of the algorithm) substantially exceeds four, hundreds of computer experiments indicate that the average number of the basic steps does not exceed six. These experiments also confirm all important facts discussed in this paper.

非洲猪瘟病毒重组载体疫苗激发/加强免疫策略的初步研究

为了选择合理的非洲猪瘟病毒(ASFV)重组载体的激发/加强免疫策略,构建表达ASFV CD2v-p30-p54融合抗原的重组伪狂犬病毒rPRV-F1,将其与表达相同融合抗原的重组腺病毒rAd-F1分为rAd-F1/rAd-F1、rAd-F1/rPRV-F1、rPRV-F1/rPRV-F1、rPRV-F1/rAd-F14个组合进行猪免疫试验,分别于免疫后不同时间采血并分离血清进行ELISA抗体检测,分离的外周血单个核细胞(PBMC)经ASFV抗原刺激后进行IFN-γ检测。免疫荧光与免疫转印试验结果显示,构建的rPRV-F1能在感染细胞中正确表达F1融合蛋白。所有免疫猪均能检测到抗原特异性抗体,加强免疫后的抗体水平显著升高。在测试的4个免疫方案中,尽管rAd-F1/rAd-F1组合初次免疫后的抗原特异性抗体水平和IFN-γ表达水平最高,但加强免疫后的抗体水平和IFN-γ表达水平最低。与此相反,尽管rPRV-F1/rAd-F1组合初次免疫后的抗体水平和IFN-γ表达水平最低,但加强免疫后的抗体水平和IFN-γ表达水平最高。这些研究结果表明rPRV/rAd是较好的ASFV重组载体疫苗的激发/加强免疫策略。

Tumor-repopulating cell-derived microparticles elicit cascade amplification of chemotherapy-induced antitumor immunity to boost anti-PD-1 therapy

Immune checkpoint blockade(ICB)therapy,particularly antibodies targeting the programmed death receptor 1(PD-1)and its ligand(PD-L1),has revolutionized cancer treatment.However,its efficacy as a standalone therapy remains limited.Although ICB therapy in combination with chemotherapy shows promising therapeutic responses,the challenge lies in amplifying chemotherapy-induced antitumor immunity effectively.This relies on efficient drug delivery to tumor cells and robust antigen presentation by dendritic cells(DCs).Here,we developed tumor-repopulating cell(TRC)-derived microparticles with exceptional tumor targeting to deliver doxorubicin(DOX@3D-MPs)for improve anti-PD-1 therapy.DOX@3D-MPs effectively elicit immunogenic tumor cell death to release sufficient tumor antigens.Heat shock protein 70(HSP70)overexpressed in DOX@3D-MPs contributes to capturing tumor antigens,promoting their phagocytosis by DCs,and facilitating DCs maturation,leading to the activation of CD8+T cells.DOX@3D-MPs significantly enhance the curative response of anti-PD-1 treatment in large subcutaneous H22 hepatoma,orthotopic 4T1 breast tumor and Panc02 pancreatic tumor models.These results demonstrate that DOX@3D-MPs hold promise as agents to improve the response rate to ICB therapy and generate long-lasting immune memory to prevent tumor relapse.

4~6岁幼儿口语产生中句法结构和动词重复的作用:来自句法启动的证据

4~6岁是幼儿句法习得的关键期,此阶段的句法表征是否受到词汇信息的影响尚存理论争议。采用句法启动范式中的句子重复-图片描述任务,以句法选择比率为指标,借助汉语及物结构(主动句、把字句和被动句),分析了幼儿在句子产生时句法结构和动词重复的作用。结果显示三种句法结构都诱发了抽象启动效应,证实幼儿在习得汉语句法知识时不依赖词汇信息。同时,动词重复只有在大龄幼儿(5~6岁)主动句的启动中才能提升启动量,表明动词增强效应与幼儿年龄以及句法结构偏好有关。此外,因句法结构偏好差异,三种结构间产生了逆偏好效应。以上结果可以从内隐学习理论的角度进行解释。

肿瘤坏死因子α预处理人脐带间充质干细胞的生物学特征分析

背景:在部分临床前及临床研究中,人脐带间充质干细胞表现出有希望的治疗结果但仍然存在效果有限的问题。因此,通过预处理的方式增强人脐带间充质干细胞的功能为干细胞培养工艺的开发提供新思路。目的:探索炎性因子肿瘤坏死因子α预处理人脐带间充质干细胞的生物学特性变化及作用机制。方法:分离获得的人脐带间充质干细胞培养至第6代,进行炎性因子肿瘤坏死因子α预处理,对比未预处理人脐带间充质干细胞和炎性因子预处理后人脐带间充质干细胞的免疫调节能力、抗炎功能、表面标志物、倍增时间、成脂成骨分化能力的变化,此外对比两组的转录组数据,分析具体机制。结果与结论:(1)与未预处理对照组相比,不同质量浓度肿瘤坏死因子α预处理的人脐带间充质干细胞均显著抑制T细胞增殖,促进Treg细胞增殖,其中1 ng/mL肿瘤坏死因子α作用效果最显著;(2)与未预处理对照组相比,不同质量浓度肿瘤坏死因子α预处理的人脐带间充质干细胞在体外炎症模型中释放更低水平的肿瘤坏死因子α和更高水平的白细胞介素10,其抗炎能力显著增强;(3)两组人脐带间充质干细胞的倍增时间、表面标志物表达无显著差异,均具有成骨成脂分化能力;(4)两组人脐带间充质干细胞的转录组变化主要体现在核因子κB信号通路和肿瘤坏死因子α信号通路的活化;(5)上述实验结果表明,肿瘤坏死因子α预处理后人脐带间充质干细胞的免疫调节及抗炎功能显著增强。

Immunogenicities of Env glycoproteins from circulating HIV-1 isolates in China focusing on the strategy of ＂DNA prime plus protein boost＂

Background The adenovirus-based HIV-1 vaccine developed by Merck Company suffered from an unexpected failure in September 2007. This generated a big shift in the strategy of HIV vaccine development with renewed focus on the induction of neutralizing antibodies. A major challenge in developing an HIV-1 vaccine is to identify immunogens and adopt delivery methods that can elicit broadly neutralizing antibodies against primary isolates of different genetic subtypes. Methods Most circulating HIV-1 isolates in China are composed of clades Thai-B, CRF_BC and CRF01_AE. In order to construct DNA vaccines against these 3 HIV-1 subtypes, DNA vaccines carrying the gp120 regions from HIV-1 isolates of GX48（AE）, GX79（AE）, NX22（BC）, GS22（BC）, HN24（Thai-B） were constructed. Expression of gp120 from these DNA vaccines was detected by Western blotting in transiently transfected 293T cells. Pilot immunizations of New Zealand white rabbits were performed using the strategy of ＂DNA prime plus protein boost＂ and the neutralizing antibody response was detected in a Tzm-bl cell based assay against different HIV-1 strains. Results Response of gp120-specific antibody was relatively low after DNA primes （mean titer=10^4.72）; however, the titer of gp120-specific antibody went up with 2 protein boosts （mean titer=10^6.81）. Above all, neutralizing antibody （Nab） titers induced by this combined approach were much better than those elicited by DNA or protein used alone （P 〈0.01）. Neutralizing activities of immunized rabbit sera against several pseudoviruses and laboratorial strains were evaluated, most rabbit sera primed with monovalent vaccine were capable of neutralizing only 1 of 5 viruses, however, sera primed with the polyvalent DNA vaccines were able to neutralize at least 2 of 5 viruses. Conclusion Polyvalent DNA prime plus protein boost is an effective immunization strategy to broaden the neutralization breadth and further research should be performed on the basis of this pilot study.