胞壁表达Der p2的重组BCG对BALB/c小鼠Th细胞免疫应答的影响

目的：观察接种以膜蛋白形式表达屋尘螨抗原Der p2基因的重组BCG(rBCG)，对BALB／c小鼠Th细胞免疫应答的影响。方法：以生理盐水为对照，分别将rBCG和BCG经腹腔注射接种于6～8wk龄和新生BALB／c小鼠，用ELISA法测定小鼠血清、脾脏T细胞培养上清(STLCS)中IL-4、IFN-γ水平，用双色荧光标记-流式细胞仪法测定脾脏细胞Th细胞亚群。结果：接种rBCG和BCG后，成年和新生小鼠血清和STLCS中IL-4水平较对照组显著降低、IFN-γ水平显著升高；无论成年鼠还是新生鼠，在CD4^ 的脾脏细胞中，IFN-γ^ 细胞的比例明显升高，而IL-4^ 细胞比例明显降低；此外，在两个年龄组小鼠，接种rBCG者脾细胞均产生了较BCG组更高水平的IFN-γ；同时，用rBCG免疫的两组小鼠脾脏CD4^ IFN-γ^ 的细胞比例也明显高于BCG免疫各组。结论：无论rBCG还是BCG通过腹腔注射免疫，均可诱导不同年龄BALB／c小鼠产生Th1免疫应答；表达在rBCG细胞壁上的Der p2被当成BCG的成分，为机体免疫系统所识别，抗原再次接触进一步刺激了Der p2特异性的Th1应答。这些结果表明，胞壁型抗原重组BCG可作为有效的疫苗，特异性地调节Th1／Th2平衡。     

旋毛虫感染经PD-1途径对BCG免疫小鼠细胞因子产生的影响?

探讨PD-1信号通路在旋毛虫感染影响卡介苗(Mycobacterium bovis bacille Calmette-Gu'erin,BCG)免疫小鼠细胞因子产生中的作用。首先,以旋毛虫肌幼虫(400条/只)分别感染C57BL/6遗传背景野生(WT)小鼠和PD-1基因缺失(PD-1~(-/-))小鼠,于感染后42 d处死小鼠,分离脾淋巴细胞以刀豆蛋白A(Concanavalin A,ConA)刺激培养48 h,ELISA检测培养上清中Th1型IFN-γ、IL-2、TNF-α,Th2型IL-4,和调节性TGF-β、IL-10细胞因子水平;进而,在上述相同感染条件下,于感染后28 d接种BCG,分别于免疫后7和28 d分离WT小鼠和PD-1~(-/-)小鼠的脾淋巴细胞,用卡介菌纯蛋白衍生物(purified protein derivative,PPD)体外刺激培养48 h,ELISA检测细胞培养上清中上述细胞因子分泌水平。结果显示,在单纯旋毛虫感染及感染后BCG免疫条件下,各细胞因子变化趋势趋于一致。WT小鼠感染组Th1型IFN-γ、IL-2水平明显低于未感染组,Th2型IL-4及调节性TGF-β、IL-10水平明显高于未感染组(P0.05),TNF-α水平无显著差异。而PD-1~(-/-)小鼠中,与未感染组相比,感染组Th1型IFN-γ、IL-2和TNF-α的下降水平,以及Th2型IL-4和调节性TGF-β、IL-10的上升水平较WT小鼠明显减小。上述结果表明,旋毛虫感染可经PD-1信号通路抑制BCG免疫诱导的Th1型细胞因子的产生,而促进Th2型细胞因子IL-4及调节性细胞因子的IL-10和TGF-β的生成。本研究为蠕虫感染抑制抗结核疫苗保护性效果的潜在机制提供了实验依据。     

结核菌H37Ra在小鼠体内诱导的免疫应答及其保护力

目的:研究结核菌H37Ra免疫小鼠后产生的特异性免疫应答以及保护效果.方法:BALB/c小鼠随机分为H37Ra组、BCG组和生理盐水(NS)组,免疫8周后处死部分小鼠,取脾淋巴细胞经体外培养、PPD刺激后,MTT法检测淋巴细胞的刺激指数,ELISA法检测培养上清液中IFN-γ和IL-4水平.另一部分免疫小鼠经腹腔感染结核分枝杆菌(Mycobacterium tuberculosis,MTB)毒株H37Rv,4周后处死,测定小鼠脏器重量指数.取稀释的小鼠脾脏和肺脏匀浆接种于改良罗氏培养基,培养21天后计数脏器荷菌量.结果:H37Ra和BCG免疫小鼠脾淋巴细胞刺激指数、IFN-γ和IL-4水平均显著高于NS对照组.感染4周后H37Ra和BCG组小鼠脏器重量指数较NS对照组均显著降低.H37Ra组小鼠脾脏和肺脏荷菌量与NS对照组比较分别下降了1.228log10CFU和0.954log10CFU,差异有显著性(P<0.05),与BCG组之间差异均无显著性.结论:H37Ra免疫小鼠后可以诱导产生Th1型免疫应答,能够抵抗毒株H37Rv的攻击,且免疫效果与BCG相当.     

CpG ODN对rHBsAg免疫小鼠Th1/Th2型免疫应答的影响

目的：初步探讨CpC寡脱氧核苷酸(CpG ODN)与重组乙型肝炎表面抗原(rHBsAg)联合免疫小鼠的Th1／Th2型免疫应答效应。方法：BALB／c小鼠经后腿胫骨前肌免疫2次，ELISA法检测血清乙型肝炎表面抗体(抗-HBs)IgG亚类IgG2a/IgG1的比值；生物活性法检测脾细胞诱生上清中的IFN-γ和IL-2含量；ABC-ELISA法检测小鼠血清中IL-4、IL-10及IL-12含量。结果：加CpG ODN组与单独注射rHBsAg组相比：抗-HBs IgG亚类IgG2a／IgG1比值明显高；Th1型细胞因子IFN-γ和IL-2的表达增强，抑制Th2型细胞因子IL-4和IL-10的产生。结论：CpCODN能够明显增强rHBsAg免疫小鼠Th1型抗体亚类IgG2a的产生，并且诱导Th1型细胞因子的表达，抑制Th2型细胞因子的表达。     

胰腺β细胞K_(Ca)3.1在2型糖尿病发病中的作用与调节机制

目的:观察胰腺β细胞中电导钙激活钾离子通道(intermediate-conductance Ca~(2+) -activated K+channel,K_(Ca)3.1)在2型糖尿病发病中的作用及调节机制。方法:应用2型糖尿病小鼠(db/db)模型,测评阻断K_(Ca)3.1对2型糖尿病表型指标的影响。分离小鼠胰腺β细胞,观察分别阻断K_(Ca)3.1和NF-κB信号通路对高糖或软脂酸诱导的NF-κB下游炎性细胞因子释放的影响。结果:K_(Ca)3.1阻断剂TRAM-34可降低db/db小鼠随时血糖水平。连续用药8周后,TRAM-34可降低db/db小鼠空腹血糖,改善葡萄糖耐量,增加餐后胰岛素水平,减轻db/db小鼠胰腺炎症并延缓β细胞的消亡。但TRAM-34不影响正常饮食C57BL/6小鼠空腹血糖和餐后血糖水平,无低血糖副作用。在分离的小鼠胰腺β细胞,分别阻断K_(Ca)3.1和NF-κB可降低高糖或软脂酸所引起的炎性趋化因子(CCL2和CCL20)的释放。结论:NF-κB活化介导胰腺β细胞K_(Ca)3.1上调,协同调节炎性细胞因子和胰岛素分泌,促发胰岛炎症和β细胞功能障碍,导致2型糖尿病。     

2型糖尿病免疫炎症的初步探讨

目的:检测2型糖尿病患者外周血Th1/Th2淋巴细胞及血清高敏c-反应蛋白(hs-CRP)的水平,以探讨免疫炎症与2型糖尿病的关系.方法:运用三色荧光标记法流式细胞术检测外周血中Th1/Th2淋巴细胞,用ELISA法测定hs-crp.结果:①2型糖尿病患者Th1数,Th1/Th2比值与正常对照组相比明显降低(P＜0.01),Th2数与正常对照组无明显差异.2型糖尿病患者外周血Th1淋巴细胞和HbA1c呈负相关关系(r=-0.688,P＜0.01).②2型糖尿病患者血清hs-CRP与正常对照组相比明显升高(P＜0.05).糖尿病患者血清hs-CRP浓度与胰岛素敏感性指数呈显著负相关(r=-0.38,P＜0.01),与甘油三酯(r=0.33,P＜0.05)、体重指数(r=0.42,P＜0.05)和空腹血糖(r=0.46,P＜0.05)有正相关关系.结论:2型糖尿病患者存在Th1/Th2淋巴细胞的失衡,血清hs-CRP水平与胰岛素抵抗程度有显著正相关,免疫炎症可能参与了2型糖尿病的发病.     

胞壁型rBCG经口服免疫可以诱导BALB/c小鼠产生抗原特异性TH1应答

目的观察胞壁型重组BCG(rBCG)经口服接种后对BALB/c小鼠TH细胞免疫应答的影响。方法以100 ml/L甘油为对照,分别将BCG和以膜蛋白形式表达屋尘螨抗原Der D2的rBCG经口服接种于8周龄BALB/c小鼠,109 CFU/d,连续5 d,用夹心ELISA测定小鼠血清、脾脏T淋巴细胞培养上清(SCS)和肠道相关淋巴细胞培养上清(Gcs)中IL-4、IFN-Υ水平,用双色荧光标记-流式细胞术测定脾脏淋巴细胞(SLC)和肠道相关淋巴细胞(GLC)中TH细胞亚群。结果免疫4周后,ELISA结果表明:BCG和。rBCG两组血清和SCS的IFN-Υ水平较对照组升高,IL-4水平降低;但两组小鼠GCS仅见IFN-Υ水平升高。流式细胞测定结果表明:在CD4 的SLC中,BCG和rBCG免疫小鼠的IL-12Rβ2 细胞比例升高,而CD30 细胞比例降低;在CD4 的GLC中,BCG和rBCG免疫小鼠的IFN-Υ 细胞比例升高;至免疫后8周,上述改变进一步明显,但BCG和rBCG两组之间差异无统计学意义。体外给予抗原刺激后,rBCG组小鼠变化更加显著,而BCG组则无明显改变。但GCS的IL-4水平始终无法测得;同时GLC中IL-5 细胞比例仍持续较低。结论无论rBCG还是BCG通过口服免疫,均可诱导BALB/c小鼠产生TH1优势免疫应答;而胞壁型Der p2-rBCG诱导产生的TH1优势应答具有Der p2抗原特异(记忆)性。     

HSPs对呼吸道合胞病毒重组蛋白抗原免疫应答的调节作用

目的考察热休克蛋白HSP70对呼吸道合胞病毒(RSV)重组蛋白抗原G1F/M2免疫应答的调节作用。方法构建并表达了Javelin-G1F/M2重组蛋白,在G1F/M2的N端引入Javelin序列,通过该序列可以实现重组蛋白与HSP70蛋白高亲和力结合。以HSP70:Javelin-G1F/M2复合物等免疫Balb/c小鼠,用乳酸脱氢酶释放法测定CTL活性,ELISA法测定IgG及其亚型IgG1和IgG2a抗体滴度,空斑抑制实验测定血清中和抗体。结果经表达和纯化获得了纯度达90%以上的融合蛋白;皮下免疫HSP70:Javelin-G1F/M2复合物可诱导高滴度的IgG抗体和强的CTL应答,其抗体滴度和CTL应答强度均优于Javelin-G1F/M2加铝佐剂腹腔免疫和单独Javelin-G1F/M2皮下免疫。HSP70:Javelin-G1F/M2复合物在诱导中和抗体方面与Javelin-G1F/M2加铝佐剂腹腔免疫基本相当。HSP70:Javelin-G1F/M2复合物可以诱导更强的IgG2a应答,IgG的亚型IgG1/IgG2a的比值明显低于Javelin-G1F/M2加铝佐剂腹腔免疫组和单独Javelin-G1F/M2皮下免疫组。结论 HSP70可能通过增强CTL应答进一步纠正Th2型优势应答,使得Th1/Th2应答更加平衡。     

八肽胆囊收缩素对经钥孔戚血蓝蛋白免疫小鼠T淋巴细胞亚群的影响

目的：探讨八肽胆囊收缩素（CCK-8）对经钥孔戚血蓝蛋白（KLH）免疫小鼠T淋巴细胞亚群的影响。方法：雌性BALB/c小鼠KLH免疫同时分别给予不同剂量CCK-8。流式细胞法检测小鼠外周血及脾细胞中CD4+、CD8+T细胞阳性百分率；RT-PCR法检测脾细胞中Th1型细胞因子IFN-γ、Th2型细胞因子IL-4 mRNA表达；ELISA法检测其培养上清中IFN-γ、IL-4水平；HE染色观察小鼠肺组织病理变化。结果：CCK-8下调KLH免疫小鼠外周血及脾细胞中上升的CD4+、CD8+T细胞阳性百分率，降低CD4+/CD8+比值；进一步提高其IFN-γ mRNA表达和培养上清中IFN-γ分泌量，同时下调上升的IL-4 mRNA表达和培养上清中IL-4分泌量；减轻KLH免疫所致小鼠肺部炎症。结论：CCK-8可调节适应性免疫应答，抑制T细胞尤其是CD4+T细胞活性；抑制Th2功能，提高Th1功能，因此可能在变态反应性疾病的发病和防治中具有一定作用。     

人IL-12表达质粒联合含信号肽Mtb8.4基因疫苗对小鼠结核杆菌感染的免疫保护效果

目的研究结核分枝杆菌含信号肽Mtb8.4(MS)基因疫苗与人白细胞介素12(hIL-12)联合免疫小鼠后,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。方法将40只C57BL/6N小鼠随机分为联合免疫组(MS基因疫苗 hIL-12组)、MS基因疫苗组、卡介苗(BCG)组、空载体组和PBS组。将基因疫苗、空载体和PBS,经肌内注射免疫各组小鼠,每隔3周免疫1次,共免疫3次;BCG组经尾部皮下注射1×106CFU BCG免疫1次。采用ELISA法检测小鼠脾细胞培养上清中细胞因子的水平;用乳酸脱氢酶(LDH)释放法检测免疫小鼠细胞毒性T细胞的杀伤活性。用结核杆菌强毒株H37Rv静脉攻击小鼠后,计数肺和脾组织中结核杆菌的菌落数。对小鼠的部分肺和脾组织作病理切片,经HE染色观察组织病变的程度,经ZN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中IFN-γ和IL-2的水平,与BCG组相当,显著高于MS基因疫苗组,IL-4分泌减少,特异性CTL的杀伤活性增强,对小鼠结核杆菌感染有较好的免疫保护效果。表现为小鼠肺和脾组织中结核杆菌的菌落数显著减少,组织病变明显减轻,其效果与卡介苗(BCG)组相当,但优于MS基因疫苗组。结论以hIL-12表达质粒与MS基因疫苗联合免疫后,能显著增强MS基因疫苗对小鼠结核杆菌感染的免疫保护效果。     

Endogenous Immune Response to Glutamic Acid Decarboxylase (GAD67) in NOD Mice is Modulated by Adjuvant Immunotherapy

We have shown that immunization of non-obese diabetic (NOD) mice with adjuvants (CFA or BCG) prevents the onset of diabetes by induction of regulatory cells. Since autoimmune responses to glutamic acid decarboxylase (GAD) are up-regulated in insulin-dependent diabetes mellitus (IDDM), in this study GAD67-specific antibody, T cell proliferation and lymphokine production patterns were analysed in the adjuvant-treated mice to characterize the regulatory mechanisms underlying the protection. We used both spontaneous diabetes and syngeneic islet transplantation models in NOD mice. Protection against spontaneous diabetes and prevention of syngeneic islet graft rejection by CFA or BCG treatment was found to be accompanied by the production of long lasting and high titre anti-GAD67 antibody of IgG1 isotype in the sera. Uponin vitrostimulation with GAD67, draining lymph node and spleen cells from CFA-immunized NOD mice or syngeneic islet-grafted and BCG-protected NOD mice produced much more IL-4, whereas there was no significant change in IFN-γ production. The strong early T cell proliferative response to GAD67 in CFA or BCG-immunized NOD mice was followed by a low or unresponsiveness state. Taken together, these results suggest a shift in Th1/Th2 balance in the GAD67-specific endogenous immune response to a change in Th2 levels after adjuvant treatment. We postulate that the protective effect of CFA or BCG is due to the diversion of GAD-specific endogenous cellular immune response to a non-pathogenic humoral response.     

In vivo apoptosis of diabetogenic T cells in NOD mice by IFN-gamma/TNF-alpha

Immunization with mycobacterial preparation such as Bacille Calmette-Guerin (BCG) or complete Freund's adjuvant (CFA) prevents the onset and recurrence of type 1 diabetes in non-obese diabetic (NOD) mice. In this study, we explored the mechanism underlying the down-regulation of diabetogenic T cells by BCG treatment. We found that the potential of splenocytes from BCG-immunized diabetic NOD mice to adoptively transfer diabetes was significantly impaired. BCG immunization sequentially induced the production of TNF-alpha, IFN-gamma and IL-4 by splenocytes, increased the expression of Fas(high) (Apo-1/CD95), Fas ligand (FasL, CD95L) and TNF receptor (TNFR) on T cells leading to T cell apoptosis. The primary role of IFN-gamma and TNF-alpha in BCG-immunotherapy was demonstrated by (i) reversing the immune regulatory effect of BCG by in vivo treatment with neutralizing anti-cytokine antibodies, (ii) inducing effect similar to BCG by treatment with these cytokines. We show that Fas and TNF are two pathways in BCG-induced apoptosis of diabetogenic T cells, since in vitro blocking FasL or TNFR1 with antibody reduced T cell apoptosis and increased T cell proliferative response. In addition, TNF-alpha and agonistic anti-Fas antibody had a synergistic effect on the in vitro apoptosis of diabetogenic T cells. Our results suggest that BCG down-regulates destructive autoimmunity by TNF-alpha/IFN-gamma-induced apoptosis of diabetogenic T cells through both Fas and TNF pathways. These studies provide a novel mechanism for blocking disease recurrence and immune modulating effect of BCG immunization in type 1 diabetes.     

Immunological and cytotoxicological characterization of tuberculin purified protein derivative (PPD) conjugated to single-walled carbon nanotubes

Tuberculosis (TB) represents one of the leading killers among all infectious disease. Protection against TB depends on the activation of T-helper type I (Th1) immune response. Carbon nanotubes (CNTs) have attracted considerable attention because of their potential applications as new nanovehicle. In the current study, tuberculin purified protein derivative (PPD) was conjugated to carboxylated single-walled carbon nanotubes (SWCNTs). Cytotoxicity of the carboxylated SWCNT and SWCNT-PPD conjugate was analyzed with MTT assay and by reactive oxygen species (ROS) and nitric oxide (NO) generation. Male BALB/c mice were immunized with BCG, PPD, SWCNT-PPD conjugate and PPD in complete Freund's adjuvant (CFA). Induction of cellular immune response was analyzed by measuring the levels of Th1 cytokines (IFN-γ and IL-12) and Th2 cytokines (IL-10 and IL-5). Immunization with non-conjugated PPD or PPD in Freund's adjuvant induced a Th2 cytokine response while immunization with BCG resulted to a mixed Th1/Th2 cytokine response. In contrast, PPD in conjugation with SWCNT generated preferentially a Th1-type cytokine response in the absence of potential cytotoxic effects.     

Recombinant BCG coexpressing Ag85B,ESAT-6 and Rv3620c elicits specific Th1 immune responses in C57BL/6 mice

Tuberculosis (TB) remains to be an enormous global health problem. The inconsistent protection efficacy of Bacille Calmette-Guérin (BCG) calls for new vaccines for TB. One choice to improve the efficacy of BCG vaccine is recombinant BCG (rBCG). Experimental evidences have revealed that Ag85B, ESAT-6 and Rv3620c are important immunodominant antigens of Mycobacterium tuberculosis. In this study, we have constructed a novel rBCG expressing fusion protein Ag85B-ESAT6-Rv3620c and evaluated the immunogenicity of this rBCG in C57BL/6 mice. Results show that there is a strong TB-specific CD4⁺ and CD8⁺ T lymphocytes proliferation in mice immunized with this rBCG vaccine. A single dose immunization of rBCG could induce a significantly strong Th1 immune response characterized by an increasing ratio of antigen-specific IgG2b/IgG1 as well as a high expression level of Th1 cytokines such as IFN-γ, TNF-α and IL-2. This conclusion was confirmed by a decreased secretion of Th2 cytokine IL-10. Moreover, this rBCG induced a strong humoral response in mice with an increasing antigen-specific IgG titer. Therefore, we concluded that this rBCG could significantly increase both Th1 type cellular immune response and antigen-specific humoral response compared with BCG. The above observations demonstrated that rBCG::Ag85B-ESAT6-Rv3620c is a potential candidate vaccine against M. tuberculosis for further study.     

Novel Recombinant BCG Coexpressing Ag85B, ESAT-6 and Rv2608 Elicits Significantly Enhanced Cellular Immune and Antibody Responses in C57BL/6 Mice

Tuberculosis (TB) remains an enormous global health problem, and a new vaccine against TB more potent than the current inadequate vaccine, the Bacille Calmette‐Guérin (BCG), is urgently needed. BCG has proven to be an effective recombinant delivery vehicle for foreign antigens because of its ability to induce long‐lived specific humoral and cellular immunity. Experimental evidences have revealed that Ag85B, ESAT‐6 and Rv2608 are important immunodominant antigens of Mycobacterium tuberculosis and are all promising vaccine candidate molecules. In this study, we have constructed a novel recombinant BCG (rBCG) expressing fusion protein Ag85B‐ESAT6‐Rv2608 and evaluated the immunogenicity of rBCG in C57BL/6 mice. Results show there is strong TB‐specific CD4⁺ and CD8⁺ T lymphocytes proliferative response in mice immunized with rBCG vaccine, especially the cytotoxic CD8⁺ T cells playing an important role in protection against TB. And rBCG immunization has induced a significantly strong Th1 immune response, characterized by the increased ratio of IgG2b/IgG1. Results also show that rBCG immunization could increase the secretion of Th1 cytokines such as TNF‐α and IL‐2 and could decrease the secretion of Th2 cytokine IL‐10. Moreover, it was shown that rBCG immunization induced a strong humoral response in mice, characterized by the elevated IgG titre. Therefore, we conclude that this rBCG immunization could increase both cellular immune response and antigen‐specific humoral response significantly as compared to BCG immunization in mice. The above results illustrated that rBCG::Ag85B‐ESAT6‐Rv2608 is a potential candidate against M. tuberculosis for further study.     

Development of mixed Th1/Th2 type immune response and protection against Mycobacterium tuberculosis after rectal or subcutaneous immunization of newborn and adult mice with Mycobacterium bovis BCG

Cell-mediated immunity plays a key role in containing the growth of Mycobacterium tuberculosis in the host. The induction of an antibody response or a mixed cell-mediated and humoral response is frequently associated with tuberculosis disease or a decrease in the ability to control M. tuberculosis load. We recently reported the induction of similar immune responses and protection by rectal, subcutaneous (SC) or intradermal administration of Mycobacterium bovis BCG in adult mice, guinea pigs and macaques. The rectal immunization, which did not induce the side-effects associated with parenteral routes (axillary adenitis) and which could be used to reduce the risks of viral transmission associated with unsafe injections in the developing world, was analysed and compared in newborn and adult BALB/c mice. The rectal and SC immunization induced, in mice immunized as newborns or as adults, a mixed T helper 1/T helper 2 (Th1/Th2) immune response; however, particularly in adult mice, after SC administration of BCG, the level of Th2 immune response is significantly higher than it is by the rectal route. Six months after immunization with BCG, rectal and SC delivery induced similar levels of protective immunity against a virulent challenge with M. tuberculosis strain (H37Rv) in mice immunized as adults, but the rectal BCG delivery triggered stronger protection than the SC delivery if mice were immunized as newborns.     

Standardized bovine colostrum derivative impedes development of type 1 diabetes in rodents

Bovine colostrum is a rich source of nutrients and immunologically active components that play a role in conveying passive immunity to the offspring, protection and maturation of new-born’s gastrointestinal tract. Colostrum has exerted positive effects in diseases affecting gastrointestinal tract, as well as type 2 diabetes (T2D). However, health-promoting effects in type 1 diabetes have not been reported. The aim of this study was to investigate therapeutic value of oral administration of standardized bovine colostrum derivative (SBCD) in three models of type 1 diabetes (T1D): spontaneously developed T1D in NOD mice and BB-DP rats, and in chemically induced T1D in C57BL/6 mice with multiple low doses of streptozotocin (MLDS). SBCD was administered per os and the disease development was evaluated by weekly measurement of blood glucose and by histological analyses of the pancreas. SBCD administration prevented diabetes development in all three models, as indicated by euglicaemia. Ex vivo analysis of cytokine expression and production in the spleen and mesenteric lymph nodes (MLN) in MLDS challenged mice revealed a strong modulation of the immune response. In the MLN cells SBCD disrupted harmful Th17 response induced by MLDS. Expression of Th1 signature cytokine IFN-γ was down-regulated in MLN cells of SBCD-treated mice, while IL-4 secretion (Th2 cytokine) was up-regulated in comparison to diabetic group. Modulation of the immune response seen in the MLN protruded to the spleen, giving overall less infiltration of immune cells to the pancreas. SBCD acted on immune cells and halted (auto) aggression towards pancreatic beta cells. Moreover, SBCD induced beta cell proliferation. Hence, this derivative could be tested in diabetes and other similar diseases with aberrant immune response.     

结核分枝杆菌Rv1626的原核表达及其免疫功能研究

结核分枝杆菌;Rv1626;原核表达;免疫原性;结核病