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。     

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。     

人乳头瘤病毒16型E5与IL-12联合基因疫苗的免疫活性

为了研制人乳头瘤病毒16型(HPV16)防治性疫苗,分析了HPV16 E5与IL-12联合基因疫苗的免疫活性。将构建的pcDNA3.1(+)/E5与pcDNA3.1(+)/IL-12联合免疫BALB/c小鼠,以ELISA测定小鼠血清中抗HPV16 E5 IgG水平、小鼠脾细胞培养上清中IFN-γ和IL-4含量;MTT法检测脾淋巴细胞增殖反应。结果显示末次免疫后,联合基因疫苗组和单基因疫苗组血清IgG A450值分别明显高于pcDNA3.1(+)组、pcDNA3.1(+)/IL-12组和PBS组(P<0.01);且联合基因疫苗组显著高于单基因疫苗组(P<0.01)。联合基因疫苗组和单基因疫苗组的IFN-γ和IL-4含量分别均明显高于pcDNA3.1(+)组、pcDNA3.1(+)/IL-12组和PBS组IFN-γ和IL-4含量(P<0.01),且联合基因疫苗组含量显著高于单基因疫苗组(P<0.01)。联合基因疫苗组和单基因疫苗组脾淋巴细胞刺激指数(SI)分别显著高于pcDNA3.1(+)组、pcDNA3.1(+)/IL-12组和PBS组(P<0.01);联合基因疫苗组与单基因疫苗组比较,SI差异无统计学意义(P>0.05)。结果表明HPV16 E5单基因疫苗以及与IL-12联合基因疫苗均能刺激机体产生较强的免疫应答,且联合基因疫苗优于单基因疫苗。     

Poly I∶C联合BCG-CpG复合佐剂对结核亚单位疫苗免疫效果的影响

目的探讨聚肌胞苷酸(Poly I∶C)联合BCG-CpG复合佐剂(BCG-CpG-DNA+Al,简称BC02)对结核亚单位疫苗的免疫效果是否有增强作用。方法 BALB/c小鼠分成5组,3组分别免疫含有不同剂量poly I∶C(10、25、50μg/剂)的结核亚单位疫苗(Ag85b+ESAT6-CFP10)/(BC02+poly I∶C)3针,间隔10 d;2组分别免疫PBS或(Ag85b+ESAT6-CFP10)/BC02作为对照。末次免疫后第7 d,分离脾淋巴细胞,进行抗原特异性的IFN-γELISPOT检测、ELISA检测和淋巴细胞增殖检测以评价细胞免疫应答。豚鼠分成4组,1组免疫含有50μg poly I∶C/剂的新亚单位疫苗(Ag85b+ESAT6-CFP10)/(BC02+poly I∶C)3针,间隔10 d;3组分别免疫(Ag85b+ESAT6-CFP10)/BC02疫苗、生理盐水和BCG作为对照。末次免疫30 d后,每只豚鼠皮下攻击250 CFU结核分枝杆菌。41 d后,解剖豚鼠,进行肝、脾、肺脏器综合病变评分和脾菌计数以评价保护力。结果含不同剂量poly I∶C的(Ag85b+ESAT6-CFP10)/(BC02+poly I∶C)疫苗免疫组小鼠的脾淋巴细胞分别经Ag85b和ESAT6-CFP10多肽刺激后,分泌IFN-γ的抗原特异性T细胞频数、IFN-γ分泌量和细胞增殖指数均较(Ag85b+ESAT6-CFP10)/(BC02)组大幅度提高,且应答强度与poly I∶C呈现较为明显的量效关系。(Ag85b+ESAT6-CFP10)/(BC02+poly I∶C)组豚鼠脏器综合病变指数(27.5±20.4)和脾菌分离数[(4.22±0.59)log10CFU]均低于(Ag85b+ESAT6-CFP10)/BC02组[35.8±27.3,(5.19±0.66)log10CFU],其中脾菌分离数的差异有显著统计学意义(P=0.003 0)。结论 Poly I∶C佐剂对结核亚单位疫苗(Ag85b+ESAT6-CFP10)/BC02诱导的细胞免疫应答和抗结核保护力均有一定的增强效果。     

分枝杆菌制剂对小鼠的免疫调节作用的初步研究

探讨不同分枝杆菌制剂对小鼠的免疫调节作用。将C57BL/6小鼠,随机分成4组分别注射生理盐水、微黄分枝杆菌、草分枝杆菌和田鼠分枝杆菌制剂,每隔2周免疫一次。免疫2次后,小鼠取脾淋巴细胞体外培养,分别以PPD、PPDB刺激,用MTT法检测T淋巴细胞增殖情况;用酶联免疫斑点法(Enzyme-Linked ImmunoSpot assay,ELISpot)检测脾细胞分泌IFN-γ情况,分析各分枝杆菌制剂对小鼠免疫应答的影响。结果显示,与对照组相比,微黄分枝杆菌制剂和草分枝杆菌制剂免疫小鼠的T淋巴细胞增殖反应和脾细胞分泌IFN-γ均明显提高,其中微黄分枝杆菌组与对照组相比有显著性差异(p<0.01)。分枝杆菌制剂可促进小鼠免疫应答。     

结核分枝杆菌海藻糖磷酸磷酸酶诱导小鼠体液和细胞免疫应答

目的 研究结核分枝杆菌(M．tuberculosis)海藻糖磷酸磷酸酶(TPP)诱导小鼠体液和细胞免疫。方法 差速离心分离结核分枝杆菌H37Rv和卡介苗(BCG)的各细胞组分,通过Western杂交检测抗原TPP在结核分枝杆菌H37Rv和BCG中的亚细胞定位情况。分别用5×10~6CFU的BCG和50μg的TPP蛋白免疫C57BL/6小鼠,检测小鼠血清中抗TPP的IgG1和IgG2a抗体效价。取免疫小鼠的脾细胞,体外抗原刺激,用酶联免疫斑点试验(ELISPOT)检测γ干扰素(IFN-γ)分泌细胞。结果 TPP亚细胞定位于结核分枝杆菌H37Rv和BCG的胞壁和细胞膜组分。TPP蛋白免疫后小鼠产生的TPP特异性IgG1和IgG2a抗体效价明显高于BCG免疫小鼠,并且IgG2a的抗体效价高于IgG1。体外抗原刺激TPP蛋白和BCG免疫小鼠的脾细胞,都能诱导较高的IFN-γ分泌。结论 结核分枝杆菌细胞壁蛋白TPP能诱导小鼠Ⅰ型辅助性T细胞介导的免疫反应,可作为抗结核疫苗的候选抗原。     

大剂量HBsAg 对HBV 转基因小鼠T 细胞免疫调节的研究

目的:研究大剂量HBsAg对HBV转基因小鼠其T细胞免疫效果的影响。方法:用大剂量血源性HBsAg免疫HBV转基因小鼠,采用ELISA方法观察转基因小鼠所诱生的HBsAg特异性Th1类细胞因子的水平,ELISPOT方法检测不同免疫方案对小鼠HBsAg特异性分泌IFN-γT细胞数量的影响,同时检测对小鼠淋巴细胞增殖的影响。结果:HBsAg组免疫后脾细胞产生的Th1类细胞因子(IFN-γ、IL-2)、HBsAg特异性分泌IFN-γT细胞及T细胞增殖水平较对照组显著增加(P<0.05)。结论:大剂量的HBs-Ag可以诱导乙肝转基因小鼠产生高水平Th1类细胞因子并打破免疫耐受。     

金线莲多糖对免疫抑制小鼠脾淋巴细胞体外增殖、分泌NO及细胞因子的影响

本试验旨在研究金线莲多糖(ARP)对免疫抑制小鼠脾淋巴细胞体外增殖、NO及细胞因子IL-2、IL-6、IFN-γ分泌水平的影响。MTT法检测小鼠脾淋巴细胞体外增殖;Griess法检测NO分泌水平;ELISA法检测细胞因子IL-2、IL-6、IFN-γ的含量。结果显示,与对照组比较,ARP在50~400μg/m L可明显促进免疫抑制小鼠脾淋巴细胞体外增殖(P0.01),促进NO分泌(P0.01),促进细胞因子IL-2、IL-6和IFN-γ分泌(P0.05,P0.01)。以上结果提示ARP能提高免疫抑制小鼠脾淋巴细胞体外免疫活性,其作用机制可能与促进免疫抑制小鼠脾淋巴细胞增殖,促进NO产生以及提高IL-2、IL-6、IFN-γ的分泌水平有关。     

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.     

新型结核病疫苗AEH/Al/IC在小鼠中的免疫原性研究

目的检测重组结核分枝杆菌(Mycobacterium tuberculosis,Mtb)融合蛋白Ag85B-ESAT6(Antigen 85 B,6-kDa early secretory antigenic target,AE)和热休克蛋白X(heat shock protein X,Hsp X)与氢氧化铝和聚肌胞苷酸(Polyinosinic-polycytidylic acid,poly I∶C)构建的新型结核病亚单位疫苗AEH/Al/IC在小鼠中的免疫原性。方法用疫苗(AEH/Al/IC)和佐剂(Al/Poly I∶C)分别免疫雌性BALB/c小鼠3剂次,每剂次间隔10 d。末次免疫后第10天,经ELISA检测小鼠血清中抗原特异性Ig G、Ig G1和Ig G2a的抗体效价,经酶联免疫斑点试验(enzyme-linked immunospot,ELISPOT)检测小鼠脾细胞分泌抗原特异性IFN-γ和IL-2的细胞频数,经ELISA检测小鼠脾细胞抗原特异性IFN-γ、IL-2和TNF-α的分泌量。结果与佐剂组相比,疫苗组诱导小鼠产生了高水平的AE和Hsp X特异性抗体;疫苗组诱导小鼠产生的AE和Hsp X特异性IFN-γ和IL-2阳性脾淋巴细胞(斑点形成细胞spot forming cells,SFC)均高于佐剂组,差异有统计学意义(IFN-γ:P0.05; IL-2:P0.05);疫苗组小鼠脾细胞AE特异性IFN-γ、IL-2和TNF-α分泌量明显较佐剂组高,差异均有统计学意义(P0.05),Hsp X特异性IFN-γ和TNF-α分泌量比佐剂组稍高,但差异均无统计学意义(P0.05)。结论结核病亚单位疫苗AEH/Al/IC具有良好的免疫原性,有希望成为一种新型的结核病预防候选疫苗。     

Immunological properties of recombinant Mycobacterium bovis bacillus Calmette-Guérin strain expressing fusion protein IL-2-ESAT-6

The live vaccine Mycobacterium bovis bacillus Calmette-Guérin (BCG) provides variable efficacy against adult pulmonary tuberculosis (TB). Recombinant BCG, expressing either immunodominant antigens or Th1 cytokines, is a promising strategy for developing a new TB vaccine. However, not much is known about whether the introduction of cytokine and specific antigen genes concurrently into the BCG strain could improve the immunogenicity of BCG. In this study, a recombinant BCG strain (rBCG) expressing the fusion protein human interleukin (IL)-2 and ESAT-6 (early secreted antigenic target-6 kDa) antigen of Mycobacterium tuberculosis was constructed. Six weeks after BALB/c mice (H-2d) were immunized with 106 colony forming units (CFUs) BCG or rBCG, splenocyte proliferation was determined with MTT [3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide] assay, IL-4 and interferon (IFN)-gamma produced by splenocytes were tested by enzyme linked immunosorbent assay (ELISA,) and the cytotoxicity of splenocytes from immunized mice to P815 cells (H-2d) expressing ESAT-6 protein was measured using CytoTox 96 Non-Radioactive Cytotoxicity Assay. Compared with native BCG-vaccinated mice, rBCG induced stronger Th1 responses that were confirmed by high lymphoproliferative responses and IFN-gamma production to culture filtrate protein (CFP) or ESAT-6 protein. Moreover, rBCG induced significant enhanced CTL responses against P815-ESAT-6 cells. Results from rBCG-immunized mice demonstrated that introducing the il-2 and esat-6 genes into BCG could enhance Th1 type immune responses to ESAT-6. Further investigation is needed by introducing other Th1 cytokines and antigens into BCG to optimize the protective efficacy against TB.     

Evaluation of immunogenicity and protective efficacy against Mycobacterium tuberculosis infection elicited by recombinant Mycobacterium bovis BCG expressing human Interleukin-12p70 and Early Secretory Antigen Target-6 fusion protein

ESAT-6 protein of Mycobacterium tuberculosis is absent in Mycobacterium bovis BCG and Mycobacterium microti and has been demonstrated to stimulate strong cell-mediated immunity. IL-12 can play crucial roles in regulating IFN-γ production and Th1 effectors production. In this study, we constructed three rBCG vaccines that could express proteins of human IL-12p70 and/or ESAT-6 and evaluated their immunogenicity and protective efficacy in mice. Our experiments illustrated that the rBCG-IE (expressing a fusion protein of human IL-12p70 and ESAT-6) was capable of inducing stronger Th1 type cell-mediated immune responses than conventional BCG, or rBCG-I (expressing human IL-12p70), or rBCG-E (expressing ESAT-6). However, the results of protective experiments showed that rBCG-IE could only confer similar and even lower protective efficacy against M. tuberculosis H37Rv infection compared with BCG vaccine.     

The synthetic antimicrobial peptide KLKL5KLK enhances the protection and efficacy of the combined DNA vaccine against Mycobacterium tuberculosis

In this study, we evaluated the potential of the synthetic antimicrobial peptide KLKL(5)KLK to augment the immune response and protective efficacy of the combined DNA vaccine against Mycobacterium tuberculosis. We demonstrated that immunization of mice with a combined DNA vaccine/KLKL(5)KLK mixture resulted in significantly higher protection than that induced by the combined DNA vaccine alone or by the Bacillus Calmette-Guérin (BCG) vaccine after challenge with a virulent M. tuberculosis strain (p < 0.01). Detailed analysis of the immune response revealed that the combined DNA vaccine/KLKL(5)KLK mixture stimulated higher IL-12 secretion, resulted in significantly more CD4(+)/CD44(high) and CD8(+)/CD44(high) T-cell production (p < 0.01), elicited 1.5- to 1.8-fold higher interferon-gamma (IFN-gamma) production, and produced stronger antigen-specific cytotoxic T lymphocyte activity than the combined DNA vaccine alone. Further, 125 days after the final immunization, mice immunized with the combined DNA vaccine/KLKL(5)KLK mixture significantly outpaced their combined DNA vaccine-immunized counterparts regarding antigen-specific IFN-gamma-producing cell numbers (p < 0.05) and antigen-specific IgG titers, indicating that KLKL(5)KLK provides a stronger and longer Th1-associated immune response. Taken together, our results indicate that the synthetic peptide KLKL(5)KLK is a potent adjuvant that can enhance and prolong the immune response of the combined DNA vaccine against M. tuberculosis.     

小鼠对结核分枝杆菌Ag85B-Esat6-HspX融合基因的免疫反应

目的研究结核分枝杆菌Ag85B-Esat6-HspX融合基因的免疫原性。方法将40只BALB/c小鼠随机分成4组,NS组、BCG组、pcDNA-HspX组和pcDNA-Ag85B-Esat6-HspX组,每组10只。BCG组只在0周时皮内注射卡介苗1次。NS组、pcDNA-HspX组及融合基因组分别于0、2、4周肌肉注射生理盐水和重组质粒DNA,共免疫3次。在免疫的第2周,4周及最后一次免疫后2周检测体血清中的总IgG水平。同时,最后一次免疫后2周,取脾细胞检测细胞免疫反应。结果构建的融合基因重组质粒DNA免疫动物后能产生针对结核杆菌特定抗原的特异性细胞免疫和体液免疫应答,具有较强的免疫原性。结论结核分枝杆菌Ag85B-Esat6-HspX融合基因可作为DNA疫苗进行保护作用的研究。     

Improved cellular immune response elicited by a ubiquitin-fused ESAT-6 DNA vaccine against Mycobacterium tuberculosis

The present study evaluated the immune response elicited by a ubiquitin-fused ESAT-6 DNA vaccine against Mycobacterium tuberculosis. BALB/c mice were vaccinated with plasmid DNA encoding ESAT-6 protein, ubiquitin-fused ESAT-6 DNA vaccine (UbGR-ESAT-6), pcDNA3-ubiquitin and blank vector, respectively. ESAT-6 DNA vaccine immunization induced a Thl-polarized immune response. The production of Thl-type cytokine (IFN-γ) and proliferative T-cell responses was enhanced significantly in mice immunized with UbGR-ESAT-6 fusion DNA vaccine, compared to non-fusion DNA vaccine. This fusion DNA vaccine also resulted in an increased relative ratio of IgG_2a to IgG_l and the cytotoxicity of T cells. Thus, the present study demonstrated that the UbGR-ESAT-6 fusion DNA vaccine inoculation improved antigen-specific cellular immune responses, which is helpful for protection against tuberculosis infection.     

BCG expressing LCR1 of Leishmania chagasi induces protective immunity in susceptible mice

Cellular immune responses are required for protective immunity against Leishmania chagasi. Immunization strategies using live intracellular bacteria (e.g., bacille-Calmette Guerin strain of Mycobacterium bovis) expressing recombinant antigens can induce cellular immune responses to these antigens. Previous studies demonstrated that the L. chagasi antigen LCR1 stimulates IFN-gamma production from T cells of infected BALB/c mice, and immunization with recombinant LCR1 partially protects against L. chagasi infection. To determine whether live bacteria could enhance the immunization potential of LCR1, we engineered BCG expressing LCR1 (BCG-LCR1). Subcutaneous immunization with BCG-LCR1, but not with BCG containing plasmid only (BCG-pMV261), elicited better protective immunity against L. chagasi infection than LCR1 protein alone. BCG-LCR1 administered intraperitoneally did not protect. Splenocytes from mice immunized s.c. with either BCG-LCR1 or BCG-pMV261 and then infected with L. chagasi promastigotes had increased antigen-induced IFN-gamma and reduced IL-10 production compared to splenocytes of control mice. We propose that BCG-LCR1 promotes a Th1-type protective immune response, and it may be a useful component of a Leishmania vaccine.     

Immune responses and protective efficacy of the gene vaccine expressing Ag85B and ESAT6 fusion protein from Mycobacterium tuberculosis

Genetic immunity is a new promising approach for the development of novel tuberculosis vaccines. In this study, it is shown that DNA vaccines expressing the fusion protein of antigen 85B (Ag85B) and early secreted antigenic target 6-kDa antigen (ESAT6) can induce high levels of specific IgG2a antibody subtype in the mice. With the prolongation of postimmunization time, the levels of IgG2a antibody decrease gradually. Although a high-level specific IgG2a antibody subtype is also elicited by classical BCG, the ratio of antibody subtypes IgG2a to IgG1 changes 4 weeks after immunization, and IgG1 is gradually shifted to the main antibody subtype. DNA vaccines also elicit cellular immunity as shown by specific spleen lymphocytes proliferation to Ag85B or ESAT6 protein and the production of high levels of IFN-gamma and IL-2, which is similar to that elicited by BCG. Vaccination of mice with DNA vaccines expressing the fusion protein Ag85B-ESAT6 results in a significant level of protection against the subsequent high-dose challenge with virulent Mycobacterium tuberculosis (MTB) H37Rv. Dramatic reduction in the number of MTB colony-forming units in the spleens and lungs is observed. Pathological examination showed that recombinant plasmid and BCG groups have only minor damage and organizational structures that are kept relatively complete, while in the control group, spleens and lungs are damaged seriously. Therefore, although the reducing degree of mycobacterial loads in the organ of mice immunized with recombinant plasmid is not more than that of BCG, through the analysis of pathological changes, we may conclude that the protective effect provided by DNA vaccine expressing the Ag85B-ESAT6 fusion protein is equivalent to that afforded by the classical BCG.     

SV40 T antigen acts as a minor histocompatibility antigen of SV40 T antigen tolerant transgenic mice

The ability of normal mice to mount an SV40 T antigen-specific cytolytic T lymphocytes response when immunized in vivo with splenocytes from the SV40 T antigen transgenic 427-line mice and restimulated in vitro with SV40-transformed fibroblasts, or when immunized with SV40 and restimulated with 427-line splenocytes, was analyzed. Both immunization schemes resulted in an SV40 T antigen-specific immune response, indicating the presence of SV40 T antigen-positive cells in the spleens of these transgenic mice. Normal mice engrafted with skin from 427 donors showed no rejection of the graft. Thus, SV40 T antigen in transgenic 427-line mice is expressed on an undefined cell type in the spleen and acts as a tissue-specific minor histocompatibility antigen.     

Construction of an encapsulated ESAT-6-based anti-TB DNA vaccine and evaluation of its immunogenic properties

Experimental preparations based on a DNA vaccine encoding the ESAT-6 antigen of Mycobacterium tuberculosis have been obtained (KpONE6) and studied for immunogenic effects in the murine model. The core of the preparation contains DNA of the recombinant plasmid pONE6 encapsulated within a spermidine-polyglucin conjugate, thereby protecting the DNA vaccine from degradation. KpONE6 induces a proliferative T-cell immune response in mice upon intramuscular immunization.