IL-2增强肺炎支原体P1C核酸疫苗的肌注免疫效果

目的:研究IL-2对肺炎支原体(Mycoplasma pneumoniae,Mp)P1C核酸疫苗经肌注免疫BALB/c小鼠后的免疫应答水平和免疫保护作用.方法:将P1C-IL-2核酸疫苗肌注免疫BALB/c鼠,ELISA检测疫苗免疫后56天小鼠血清IgG和IgG亚类、支气管灌洗液中SIgA、IFN-γ和IL-4的水平;用2×107 Mp菌落形成单位鼻饲感染BALB/c鼠,建立感染小鼠模型,病理切片检测Mp感染后小鼠肺部炎症病理改变;将系列10倍稀释的支气管灌洗液接种于SP4固体平板,并进行菌落计数.结果:P1C-IL-2核酸疫苗免疫组小鼠血清中的总IgG、IgG1、IgG2a、IFN-γ和IL-4水平均较P1C单基因疫苗组显著增高(P＜0.05),但两组支气管灌洗液中SIgA差异无显著性(P＞0.05).Mp感染后第1、3、6天P1C-IL-2双基因疫苗组小鼠肺组织病理评分(HPS)较P1C单基因疫苗免疫组显著增高,但支气管灌洗液中的Mp菌落数明显减少;第9天后两组HPS和Mp菌落数差异无显著性.结论:IL-2能显著增强P1C疫苗肌注的免疫保护作用和免疫应答水平,但同时在Mp感染早期激发了较重的肺组织炎症.     

IL-12、IL-18基因对HIV-1外膜蛋白基因疫苗诱导的免疫应答的影响

目的 研究IL-12、IL-18基因对HIV-1外膜蛋白基因疫苗诱导免疫应答的影响，以探求HIV-1核酸疫苗的新策略。方法 pVAX1GP120联合IL-12、IL-18基因或者pVAX1GP120单独免疫BALB／c小鼠，采用ELISA检测免疫小鼠的特异性抗体和IFN-γ水平，以NIT比色法检测免疫小鼠脾淋巴细脯增殖，用乳酸脱氢酶（LDH）试验检测小鼠特异性细胞毒性T淋巴细胞（CIL）的应答。结果 与pVAX1GP120免疫组比较，pVAX1GP120联合IL-12、IL-18基因免疫组小鼠血清的抗HIV-1 gp120抗体滴度升高，IFN-γ升高，小鼠的脾淋巴细胞增殖实验刺激指数（SI）以及特异性CTL活性均高，差异均有统计学意义（P〈0．01）。结论 IL-12、IL-18基因联合HIV-1核酸疫苗免疫小鼠，有可能增强特异性TH1细胞和CTL反应，IL-12、IL-18基因对体液免疫可能有抑制作用。因此，IL-12、IL-18基因对于治疗性HIV-1核酸疫苗可能是具有较好应用前景的免疫佐剂。     

肺炎支原体P1蛋白片段免疫学活性及黏附功能的研究

目的 了解肺炎支原体(Mycoplasma pneumoniae,Mp)P1蛋白第1125 ～1395氨基酸片段(P1C蛋白)的免疫学活性及其细胞黏附作用.方法 构建用于表达重组P1C片段(rP1C)的原核表达载体pGEX6p-2/p1c,采用SDS-PAGE和Western blot鉴定rP1C.采用基于GST的亲和层析法提纯rP1C,提纯的rP1C免疫BALB/c小鼠,ELISA检测小鼠抗rP1C血清的效价.采用Western blot检测rP1C对Mp感染患者血清的免疫反应性.采用间接免疫荧光法检测rP1C黏附HeLa细胞及其免疫血清黏附抑制作用.结果 所构建的原核表达系统能有效表达相对分子质量约为66×103的可溶性rP1C.rP1C免疫小鼠后,其抗血清ELISA效价高达1∶64000.rP1C能被Mp感染者血清及小鼠抗rP1C血清识别并与之结合.rP1C能黏附HeLa细胞,其抗血清可阻断Mp对HeLa细胞的黏附,该黏附阻断作用随抗血清浓度增高而增强.结论 rP1C具有良好的免疫原性和免疫反应性及黏附细胞功能,可作为Mp疫苗及血清学检测的候选抗原.     

白三烯受体拮抗剂介导NLRP3/Caspase-1/IL-1β信号通路改善支原体肺炎小鼠Th1/Th2免疫失衡

目的 探究白三烯受体拮抗剂对支原体肺炎小鼠Th1/Th2免疫的影响及可能机制。方法 30只BALB/c小鼠随机分为对照组（Control组）、肺炎支原体感染组（MP组）和白三烯受体拮抗剂孟鲁斯特（MK组）,通过滴鼻接种菌液建立支原体肺炎小鼠模型。取材后对各组小鼠计算肺湿重指数;HE染色观察肺组织病理变化;ELISA法检测肺泡灌洗液中IL-1β、IL-12、IFN-γ、TNF-α含量;TUNEL法检测肺组织细胞凋亡情况;流式技术检测外周血CD4+/CD8+水平;Western blot法检测肺组织NLRP3、pro-caspase1、pro-IL1β的表达水平。结果 白三烯受体拮抗剂改善支原体肺炎小鼠肺脏损伤,抑制IL-1β、IL-12、IFN-γ、TNF-α的分泌,抑制细胞凋亡,改善Th1/Th2免疫失衡,下调NLRP3、pro-caspase1、pro-IL1β的表达。结论 白三烯受体拮抗剂通过介导NLRP3/Caspase-1/IL-1β信号通路改善Th1/Th2免疫失衡,降低肺脏损伤。     

IL-18和HIV-1 gag-gp120嵌合基因DNA疫苗联合免疫小鼠的免疫应答

目的 :探讨IL 18和HIV 1gag gp12 0嵌合基因的DNA疫苗联合免疫小鼠的免疫应答。方法 :构建含IL 18的真核表达质粒pVAXIL18,将他与表达HIV 1gag gp12 0嵌合基因的核酸疫苗质粒pVAXGE共同肌注免疫BALB/c小鼠 ,检测免疫小鼠脾特异性CTL杀伤活性和血清抗体滴度。结果 :联合免疫组小鼠脾特异性CTL杀伤活性和血清抗体水平均显著高于单独免疫组 (P <0 .0 5 ) ,空白质粒对照组 (P <0 .0 1)和PBS对照组 (P <0 .0 1)。结论 :IL 18和HIV 1gag gp12 0嵌合基因的DNA疫苗联合免疫可诱导小鼠产生特异性细胞和体液免疫 ,且IL 18发挥了免疫佐剂的作用。     

肺炎支原体肺炎和哮喘患儿肺炎支原体特异性IgE检测的分析

通过免疫手段 (SDS PAGE及Westernblot)分析MP引起变态反应的抗原成分 ,比较有哮喘史及无特应症的MP感染者特异性IgE阳性率 ,并探讨与MP特异性IgE产生的有关因素。MP IgM阳性的支气管肺炎患儿 35例 (平均年龄 6 0± 3 4岁 )及支气管哮喘患儿 32例 (平均年龄 6 7± 3 3岁 ) ,MP IgM、IgA均为阴性的正常健康者 2 7例 (平均年龄 7 0± 3 6岁 )作为对照组 ;采用免疫印迹技术观察上述各组待测血清针对所分离MPFH株菌体粉碎后蛋白成分的杂交条带 ,并对其出现频度进行统计分析 ;同时应用ELISA方法检测血清总IgE。结果SDS PAGE显示MP蛋白成分有十几条。与IgE反应的抗原多肽的相对分子质量为 2 16 0 0 0、 2 0 5 0 0 0、 170 0 0 0、 6 80 0 0、 5 6 0 0 0 ,其中前三者抗原性最强 ,不同组别、病程及年龄出现率明显高于后两者 (P <0 0 5 )。MP IgE阳性率 :MP感染组 71 4 %、哮喘组 78 13%、对照组 19 2 3% ,前两组间无明显差异 ,均显著高于对照组 (P <0 0 0 5 )。MP IgE阳性率在感染 8d后上升 ,2 8d后逐渐下降。与MP IgM滴度、血清T IgE无明显直接关系。结论 :(1)MP菌体粉碎后蛋白成分复杂 ,与IgE反应的抗原相对分子质量为 2 16 0 0 0、 2 0 5 0 0 0、 170 0 0 0、 6 80 0 0、 5 6 0 0 0 ,高分子成分抗原性强     

粘膜佐剂LTB优化的抗淋病ltB-nspA融合基因疫苗鼻饲免疫效果研究

目的:用真核重组质粒pcDNA3.1(-)/ltB-nspA鼻饲免疫小鼠,探索粘膜佐剂LTB辅佐NspA所诱发的特异性体液免疫应答和细胞免疫应答水平。方法:对真核重组质粒行PCR及双酶切鉴定后大量制备,经鼻饲途径免疫雌性BALB/c小鼠,间接ELISA法检测血清中NspA特异性IgG抗体水平及小鼠生殖道灌洗液中NspA特异性sIgA抗体水平;MTT法检测脾淋巴细胞增殖水平,ELISA双抗体夹心法检测脾淋巴细胞培养上清IFN-γ含量。结果:融合基因pcDNA3.1(-)/ltB-nspA组小鼠生殖道灌洗液中sIgA(A450:0.316±0.045)明显高于pcDNA3.1(-)/nspA单基因组(P0.05)和其它对照组(P0.01);小鼠血清中IgG(A450:0.643±0.156)水平、脾淋巴细胞刺激指数(SI:1.65±0.32)和脾淋巴细胞诱生的IFN-γ(160.56±25.67pg/ml)水平均明显高于pcDNA3.1(-)/ltB、空质粒pcDNA3.1(-)和PBS对照组(P0.01)。结论:pcDNA3.1(-)/ltB-nspA融合基因疫苗经鼻饲免疫,能够诱导小鼠产生较强的特异性体液免疫应答和细胞免疫应答;粘膜佐剂LTB可辅佐NspA诱导小鼠产生更高水平的生殖道粘膜免疫。     

支原体肺炎患儿MCP-1、IL-6、TNF-α检测的临床分析

在临床实践中,肺炎支原体肺炎（MPP）与非肺炎支原体肺炎（非MP肺炎）的临床过程差异很大,本文旨在通过对肺炎儿童单核细胞趋化蛋白-1（MCP—1）、白细胞介素-6（IL-6）、肿瘤坏死因子（TNF-α）的测定,探讨两者发病机制的差异及肺炎患儿MCP-1、IL-6、TNF-α检测的临床意义,现报道如下。     

IL-12对小鼠肥大细胞瘤基因疫苗的免疫学作用

目的 研究小鼠肥大细胞瘤P815基因疫苗和鼠IL-12对该疫苗的免疫学作用。方法 将小鼠肥大细胞瘤P815特异抗原基因P1A克隆到真核表达质粒pCI-neo中；用P815细胞对DBA/2小鼠右腹侧皮下注射，构建P815小鼠肿瘤模型；以重组基因疫苗单独或与鼠IL-12真核表达质粒一起肌肉注射，观察肿瘤的消长，特异细胞毒T淋巴细胞激活和抗全的生成情况。结果 重组基因疫苗在体外有很好的表达，注射后CTL的杀伤效率为40%，IL-12共注射的CTI，杀伤效率达到60%，免疫后，30%小鼠的肿瘤出现消退；同IL-12共注射则有50%的小鼠的肿瘤出现消退，2种情况下都不能检测到任何特异抗体的产生。结论 重组P1A肿瘤疫苗能有效激活机体的肿瘤特异免疫应答；基因疫苗对小鼠P815肿瘤的治疗作用主要归因于细胞免疫；IL-12有增强这种免疫应答的作用。     

A single subcutaneous or intranasal immunization with adenovirus-based SARS-CoV-2 vaccine induces robust humoral and cellular immune responses in mice

Optimal vaccines are needed for sustained suppression of SARS-CoV-2 and other novel coronaviruses. Here, we developed a recombinant type 5 adenovirus vector encoding the gene for the SARS-CoV-2 S1 subunit antigen (Ad5.SARS-CoV-2-S1) for COVID-19 immunization and evaluated its immunogenicity in mice. A single immunization with Ad5.SARS-CoV-2-S1 via S.C. injection or I.N delivery induced robust antibody and cellular immune responses. Vaccination elicited significant S1-specific IgG, IgG1, and IgG2a endpoint titers as early as 2 weeks, and the induced antibodies were long lasting. I.N. and S.C. administration of Ad5.SARS-CoV-2-S1 produced S1-specific GC B cells in cervical and axillary LNs, respectively. Moreover, I.N. and S.C. immunization evoked significantly greater antigen-specific T-cell responses compared to unimmunized control groups with indications that S.C. injection was more effective than I.N. delivery in eliciting cellular immune responses. Mice vaccinated by either route demonstrated significantly increased virus-specific neutralization antibodies on weeks 8 and 12 compared to control groups, as well as BM antibody forming cells (AFC), indicative of long-term immunity. Thus, this Ad5-vectored SARS-CoV-2 vaccine candidate showed promising immunogenicity following delivery to mice by S.C. and I.N. routes of administration, supporting the further development of Ad-based vaccines against COVID-19 and other infectious diseases for sustainable global immunization programs.     

HSV-2gD模拟抗原表位、HBsAg与IL-18融合蛋白DNA疫苗的免疫效果观察

目的:研究串联重组核酸疫苗pc(pcDNA3.1)-S(HBsAg)-P6-IL18和pc(pcDNA3.1)-S(HBsAg)-NP6-IL18对机体的免疫效果,P6是我们前期采用噬菌体展示技术筛选出的HSV-2gD的模拟抗原表位,NP6为与HSV-2gD模拟抗原表位P6最相似的天然抗原表位序列。方法:分别将空质粒pcDNA3.1(阴性对照组)和构建的真核表达质粒pc-S-P6-IL18和pc-S-NP6-IL18肌内注射免疫接种BALB/c小鼠3次,每次间隔2周。末次免疫后2周眼眶静脉采血,ELISA法检测小鼠血清特异性抗体滴度、IFN-γ及IL-18含量;末次免疫后一月,处死小鼠,无菌分离脾脏,用刀豆蛋白A刺激淋巴细胞,采用MTT法测定脾淋巴细胞增殖率。结果:重组核酸疫苗pc-S-P6-IL18和pc-S-NP6-IL18免疫小鼠后可刺激血清特异性抗体(抗HBsAg抗体和抗HSV-2gD模拟表位抗体)的产生,与阴性对照组相比可诱导分泌较高水平的IFN-γ和IL-18,可促进小鼠脾淋巴细胞的增殖。结论:重组核酸疫苗pc-S-P6-IL18和pc-S-NP6-IL18能诱导较强的细胞免疫和体液免疫,可用于今后预防HBV和HSV-2感染的研究。     

治疗性HBV DNA疫苗诱导健康Balb/c小鼠细胞免疫应答的实验研究

目的探讨治疗性HBVDNA疫苗对健康Balb/c小鼠表达Th1类细胞免疫应答的影响。方法治疗性HBVDNA疫苗(pS2·S+pFP)以剂量(50μg+50μg)/只对Balb/c小鼠进行接种,以酶联免疫斑点法(ELISPOT)、流式细胞术(FACS)分析特异性分泌IFN-γ阳性T细胞的免疫效果。结果免疫6周时,实验组用HBsAg刺激后其诱生的IFN-γ细胞频数(34±15.3)较不用HBsAg组(4±4.4)高(P<0.05,t=5.65),也较同期空载体免疫对照组(3±3.6)高(P<0.05,t=5.21);治疗性HBVDNA疫苗诱导小鼠CD4+T细胞表达IFN-γ的百分比实验组[(0.28±0.17)%]与对照组[(0.20±0.03)%]比较,无显著性差异(P>0.05,t=0.21);而诱导CD8+T细胞表达IFN-γ的百分比实验组[(0.69±0.08)%]与对照组[(0.24±0.12)%]比较,具显著性差异(P<0.05,t=4.167)。结论治疗性HBVDNA疫苗能有效诱导T细胞分泌HBsAg特异性IFN-γ因子,并以CD8+T细胞分泌占优而发挥细胞免疫应答的优势。     

pEGFP-C3-B7.2-MAGE-1融合蛋白诱导特应性抗肿瘤免疫应答的研究

目的:构建重组表达载体pEGFP-C3-B7.2-MAGE-1,研究人B7.2/MAGE-1基因修饰的食管癌细胞作为瘤苗的抗肿瘤作用.方法:通过RT-PCR扩增B7.2和MAGE-1的cDNA,以pEGFP-C3为载体,构建pEGFP-C3-B7.2-MAGE-1重组载体,通过脂质体转染技术转染人食管癌细胞株EC9706,外周血来源的树突状细胞(DC)负载肿瘤抗原后,与自体T淋巴细胞共培养3天,获得细胞毒性T淋巴细胞(CTL),用四甲基偶氮唑蓝(MTT)法检测CTL对转染和未转染pEGFP-C3-B7.2-MAGE-1的食管癌细胞EC9706的杀伤活性.结果:CTL对转染pEGFP-C3-B7.2-MAGE-1的肿瘤细胞的杀伤活性大于转染pEGFP-C3和未转染细胞的杀伤活性(P＜0.05).结论:成功构建了真核共表达载体pEGFP-C3-B7.2-MAGE-1,人B7.2/MAGE-1基因修饰的EC9706肿瘤细胞瘤苗,可诱导出明显的抗EC9706细胞的免疫效应.     

Augmented humoral and cellular immune responses induced by canine adenovirus type 1 DNA vaccine in BALB/c mice

Infectious canine hepatitis (ICH) is caused by canine adenovirus type 1 (CAV-1), which severely harms infected animals. Vaccination provides an effective approach to preventing canine infectious diseases. With the objective of exploring a new vaccination strategy that may prevent or cure ICH, we constructed a DNA vaccine, pVAX1-CpG-Loop, and evaluated its immune efficacy. We found that vaccination of BALB/c mice with the DNA vaccine alone, or priming with DNA vaccine and boosting with the Loop protein, resulted in the following: (1) High-level specific antibody (IgG) against CAV-1 was induced; (2) T cell activation was elicited; and (3) neutralizing antibodies were detectable in immunized mice. Collectively, these data indicate that the availability of a DNA vaccine could prevent hepatitis contagiosa canis.     

应用小肽融合蛋白免疫诱导抗HER-2体液免疫反应

目的应用HER-2 B细胞表位模拟小肽Mut与Hsc70的融合蛋白诱导抗小肽和抗HER-2的体液免疫反应。方法将Hsc70和Mut小肽序列定向插入pQE40载体中,构建pQE40-Hsc70-Mut原核表达质粒,并诱导表达、纯化融合蛋白Hsc70-Mut。常规免疫Balb/c小鼠,应用ELISA、Western blot检测小鼠血清中抗小肽Mut和抗HER-2的体液免疫反应。结果成功构建了pQE40-Hsc70-Mut原核表达质粒,Hsc70-Mut融合蛋白在大肠杆菌SG13009能够实现可溶性表达,应用Ni-NTA纯化可得到纯度>90%的融合蛋白;Hsc70-Mut免疫小鼠可产生抗Mut小肽的免疫反应,部分小鼠同时可产生抗HER-2的体液免疫反应。结论 Hsc70-Mut融合蛋白免疫小鼠可产生抗小肽和抗HER-2的体液免疫反应,为HER-2疫苗的研制奠定了一定基础,同时应用小肽融合蛋白免疫也为小肽免疫提供了一种新的免疫策略。     

Comparison of host responses after intranasal infection of guinea-pigs with Mycoplasma genitalium or with Mycoplasma pneumoniae

Guinea-pigs were infected intranasally with Mycoplasma genitalium or Mycoplasma pneumoniae. The lung lesions produced by the two mycoplasmas were comparable in extent and histological pattern. Sera of both animal groups taken 2 weeks after infection reacted strongly in the complement fixation test with the M. pneumoniae glycolipid extract. In an ELISA using the respective adherence proteins (P1-protein of M. pneumoniae and MgPa of M. genitalium), strong specific activity, but also considerable cross-reactions were found. Epitope analysis by using overlapping octapeptides of a P1-region immunologically active in human M. pneumoniae infections and of the corresponding MgPa-region revealed six common epitopes but also one M. genitalium and two M. pneumoniae specific determinants. For analysis of a possible pathogenicity of M. genitalium in the human respiratory tract species-specific tests have to be developed.     

Modulation of immune responses to bovine herpesvirus-1 in cattle by immunization with a DNA vaccine encoding glycoprotein D as a fusion protein with bovine CD154

The objective of this study was to determine whether a DNA vaccine encoding bovine CD154 linked to a truncated version of bovine herpesvirus-1 (BHV-1) glycoprotein D (tgD-CD154) induces enhanced tgD-specific immune responses in cattle. In vitro characterization demonstrated that tgD and tgD-CD154 both bind to cultured bovine B cells, whereas only tgD-CD154 induces interleukin-4-dependent proliferation, suggesting that tgD-CD154 specifically binds the CD40 receptor and induces receptor signalling. Calves were immunized with plasmid encoding either tgD or tgD-CD154 by intradermal injection with a needle-free device. After two immunizations, tgD-specific immune responses were observed in both vaccinated groups and after challenge with BHV-1 these responses further increased. Animals immunized with plasmid encoding tgD-CD154 had significantly higher tgD-specific serum titres of immunoglobulins G and A but significantly lower numbers of tgD-specific interferon-gamma-secreting cells than animals immunized with plasmid encoding tgD after BHV-1 challenge. This suggests that the expression of an antigen as a chimeric protein with CD154 can qualitatively alter immune responses in cattle. Since we previously showed that plasmid encoding tgD-CD154 induces significantly enhanced secondary tgD-specific antibody responses in sheep, there appear to be interspecies differences in the immune responses induced by tgD-CD154, which suggests that both proteins in the chimeric molecule may influence protein targeting and the induction of an immune response.     

IgG responses to intranasal immunization with cholera-toxin-immobilized polymeric nanospheres in mice

IgG responses to antigen-nanosphere hybrids were studied in mice. Cholera toxin (CT) was covalently immobilized onto the surface of polymeric nanospheres (NS) with a nanophase-separated structure consisting of a polystyrene core and a poly(methacrylic acid) graft corona. Reaction conditions favoring the dehydroxide condensation reaction of the amino group of the CT with the carboxyl group of NS effectively immobilized CT onto their surface. When CT-immobilized nanospheres (CT-NS) were suspended in aqueous solution and administrated to mice either intranasally or intramuscularly, serum IgG titers elevated with increasing time and reached a maximum level at 8 weeks after immunization. On the other hand, intranasal administration of CT alone induced an even higher serum IgG titer than that of CT-NS at 4 weeks. However, the titer gradually decreased thereafter. Thus, polymeric NS may be an effective substrate to covalently immobilize antigen on their surface, steadily inducing a high level of IgG production in response to the intranasal administration.