重组幽门螺杆菌疫苗口服免疫BALB/c小鼠的研究

目的研究重组幽门螺杆菌疫苗口服免疫BALB/c小鼠后免疫保护效果和维持时间，并初步探讨其免疫机制。方法ELISA检测特异性抗体水平；同时ELISPOT检测派伊尔结特异性抗体分泌细胞；RT-PCR显示T淋巴细胞IFN-γ、IL-4 mRNA表达差异；以培养、组织切片、尿素酶试验结果判断攻毒保护率。结果(1)疫苗组在胃、肠、气管冲洗液和血清产生高水平抗体；(2)疫苗组小鼠派伊尔结特异性抗体分泌细胞显著升高(P=0)；(3)抗原刺激后，免疫组T淋巴细胞的IFN-γ、IL-4 mRNA表达量升高；(4)免疫组攻毒保护率为86．7％-92．8％，且至少维持30周。结论重组幽门螺杆菌疫苗口服免疫小鼠后有良好的预防Hp感染作用；疫苗诱导的可能是TH1／TH2型免疫应答。     

滤泡调节性T细胞在病毒感染与疫苗免疫中的作用及机制研究进展

滤泡调节性T细胞(T follicular regulatory cell, Tfr)是近年来发现的一类CD4 ＋ T细胞亚群,其来源于调节性T细胞(T regulatory cell, Treg),兼具Treg细胞及滤泡辅助性T细胞(T follicular helper cell, Tfh)相似的生物学特...     

Immunological memory after somatic transgene immunization is positively affected by priming with GM-CSF and does not require bone marrow- derived dendritic cells

Inoculation of plasmid DNA is a promising vaccination approach but optimal regimes and ways to enhance immunogenicity remain to be established. Among natural immunological adjuvants, granulocyte-macrophage colony-stimulating factor (GM-CSF) was shown to increase the potency of immunization against tumor cells and protein antigens. Here we studied the effect of GM-CSF on memory responses against a 12-mer B cell epitope in mice primed with a single DNA inoculation. The results show that GM-CSF given at priming as a DNA/GM-CSF chimeric vaccine enhances the magnitude of the anamnestic response irrespective of the form of antigen used subsequently in the booster immunization. Using mice lacking bone marrow-derived dendritic cells we also determined that the enhancing effect is not strictly dependent on these cells. These results expand our understanding of the activity of GM-CSF in vivo as a modulator of the immune response including immunological memory.     

肺结核患者治疗前后血清GM-CSF和hs-CRP水平检测的临床意义

探讨了肺结核患者治疗前后血清粒细胞巨噬细胞集落刺激因子(GM-CSF)和hs-CRP水平的变化及其意义.应用放免法和免疫比浊法对40例肺结核患者进行了血清GM-CSF和hs-CRP水平测定,并与35名正常人作对照.在治疗前肺结核患者血清GM-CSF和hs-CRP水平均显著高于正常人组(P<0.01),经3个月治疗后血清GM-CSF和hs-CRP水平与正常人比较无显著性差异(P>0.05).患者治疗前后的血清GM-CSF和hs-CRP水平具有显著性差异(P<0.01).检测肺结核患者血清中GM-CSF和hs-CRP水平的变化与患者的病情和预后密切相关,有重要的临床价值.     

全反式维甲酸对基因免疫应答的调节作用

目的　研究全反式维甲酸 (ATRA)对TR4 2 1 hCGβ质粒基因免疫诱生的特异性细胞免疫与体液免疫应答的调节作用。方法　肌肉注射重组质粒TR4 2 1 hCGβDNA(每只鼠 5 0 μg 10 0 μl)初次免疫小鼠 ,以灌胃的方式给予ATRA ,并以灌溶剂和TR4 2 1质粒免疫为对照 ;3周与 6周后经同样的方式加强免疫各组小鼠 ,采用ELISA方法对基因免疫小鼠血清中IgG抗体水平进行动态观察 ,分析小鼠血清中IgG抗体亚类 ;3H TdR掺入法测定特异性细胞增殖和细胞杀伤功能。结果　ELISA结果表明 ,TR4 2 1 hCGβ质粒基因免疫诱生较高的抗hCGβ抗体水平 ,ATRA增强TR4 2 1 hCGβ质粒基因免疫诱生的抗hCGβ特异性IgG抗体水平并且伴随IgG2a IgG1显著性降低 ;TR4 2 1 hCGβ质粒基因免疫诱生较强的淋巴细胞增殖活性和CTL活性 ,ATRA抑制TR4 2 1 hCGβ质粒基因免疫诱生的特异性细胞增殖和细胞杀伤功能。结论　ATRA促进基因免疫诱生的TH2免疫应答 ,抑制TH1型免疫应答 ,为改变基因免疫诱生的特异性免疫应答类型提供了一条新的途径。     

Early T helper cell programming of gene expression in human

Molecular mechanisms guiding naïve T helper cell differentiation into functionally specified effector cells are intensively studied. The rapidly growing knowledge is mainly achieved by using mouse cells or disease models. Comparatively exiguous data is gathered from human primary cells although they provide the “ultimate model” for immunology in man, have been exploited in many original studies paving the way for the field, and can be analyzed more easily than ever with the help of modern technology and methods. As usage of mouse models is unavoidable in translational research, parallel human and mouse studies should be performed to assure the relevancy of the hypothesis created during the basic research. In this review, we give an overview on the status of the studies conducted with human primary cells aiming at elucidating the mechanisms instructing the priming of T helper cell subtypes. The special emphasis is given to the recent high-throughput studies. In addition, by comparing the human and mouse studies we intend to point out the regulatory mechanisms and questions which are lacking examination with human primary cells.     

Antigen-specific T cell response in infants after recombinant hepatitis B virus vaccination at birth: evaluation of T helper lymphocyte diversity

Recombinant hepatitis B virus antigen (rHBsAg)-specific CD4+ T cell clones (TCC) were isolated and expanded from the peripheral blood of nine children vaccinated at birth against the hepatitis B (HB) virus. Four of them responded with protective antibody production (responders), three subjects were unable to produce detectable antibody levels even after revaccination (nonresponders), and two infants produced antibodies only after revaccination (slow responders). TCC were then characterized for their ability to produce cytokines known to be important for T cell expansion (interleukin-2, IL-2) and/or effector functions (IL-4, IFN-gamma, IL-10). Results demonstrated that the frequency of rHBsAg-specific TCC in the samples of nonresponders was comparable to or higher than that in the samples of responders. Nevertheless, the majority of TCC obtained from responders or from slow responders before revaccination displayed the T helper 1 (T(H1))-dominant phenotype, while the majority of TCC obtained from nonresponders were nonpolarized T lymphocytes. After revaccination, the distribution of the different T(H) subsets in slow responders was heterogeneous. Overall, our present data suggest that an absence or delay in developing an rHBsAg-specific antibody response to vaccination is not associated with the capacity to generate an Ag-specific T cell response. However, compared to responders, nonresponding infants react to the rHBsAg vaccination with a reduced capacity to expand and differentiate toward polarized T(H) cells.     

急性期川崎病患儿滤泡辅助性T细胞改变观察

目的 探讨滤泡辅助性T细胞(Tfh细胞)在儿童川崎病(Kawasaki disease,KD)中的数量变化及其可能机制.方法 急性期川崎病患儿20例,采用流式细胞术检测外周血CD4+CXCR5+ICOS+T细胞(Tfh)的比例,采用real-time PCR检测转录调节因子Bcl-6、Blimp-1 mRNA表达,酶联免疫吸附试验检测血浆中IL-4和IL-21浓度;20例同龄健康儿童作为对照组.结果 (1)急性期KD患儿Tfh细胞比例明显高于正常对照组[(2.6±0.6)％vs(1.8±0.7)％,P＜0.05];(2)Tfh细胞转录因子Bcl-6 mRNA表达较正常对照组明显增高(P＜0.05),其拮抗因子Blimp-1 mRNA表达降低(P＜0.05);(3)血浆IL-21和IL-4蛋白浓度明显高于正常对照组(P＜0.05).结论 Tfh细胞过度活化可能参与了KD免疫发病机制,Bcl-6/Blimp-1表达失衡,IL-4和IL-21细胞因子微环境改变可能与Tfh细胞异常活化有关.     

Peptide immunization in humans: a combined CD8+/CD4+ T cell-targeted vaccine restimulates the memory CD4 T cell response but fails to induce cytotoxic T lymphocytes (CTL)

Immunization with short antigenic peptides represents a potential strategy to induce peptide-specific CTL in vivo. In this study, a synthetic vaccine consisting of an HIV-derived, HLA-A2.1-binding CTL epitope and a tetanus toxin-derived T helper epitope was evaluated for its capacity to induce peptide-specific CTL in humans. Thirteen volunteers were immunized and boosted twice with 100 μg of the CTL epitope plus 300 μg of the T helper peptide (p30). Peripheral blood mononuclear cells (PBMC) were regularly analysed for cytotoxic and proliferative responses before, between and after the immunizations, and the serum was tested for anti-peptide antibodies. No unequivocal induction of HIV peptide-specific CTL in any of the volunteers was observed. However, a wide pattern of mild and transient side reactions was observed, ranging from local redness at the injection site to generalized exanthema, myalgias, arthralgias and fever. The side-effects were related to the T helper epitope, as they were similar to the side-effects experienced after tetanus immunization, correlated to the magnitude of the p30-specific in vitro proliferative response, and occurred only if p30 was co-injected. No antibodies against the HIV-derived peptides nor against p30 were detectable in the serum after repeated immunizations. The data suggest that the CTL peptide, at the concentration used in this study, failed to induce a cytotoxic immune response in vivo, although the T helper peptide seems to be capable of restimulating the specific memory T cells.     

CD25含量与T辅助细胞对IL-2的促增殖反应性

目的 研究不同激活状态下T辅助细胞(Th)中IL-2R各亚基的表达变化及对IL-2反应的相关性.方法 以包被的抗CD3抗体激活Th1细胞,同时设立未激活对照.3H掺入法测定其对IL-2的促增殖反应;real-time PCR检测IL-2R各亚基编码基因的表达;流式细胞术检测CD25及CD122的含量;以I125标记的IL-2检测不同状态的Th1细胞对IL-2的亲和力.脂质体法转染IL-2Rα siRNA至激活的Th1细胞,比较不同CD25含量时Th1细胞对IL-2的反应性.自小鼠体内分离CD4细胞,以抗CD3抗体激活后在不同时间点收集细胞,比较它们的CD25含量及对1L-2的反应性.结果 较未激活对照相比,激活的Th1细胞中IL-2Rα亚基,即CD25的表达显著增加,而其他两个亚基则无变化;同时伴有对IL-2亲和力的升高,但对IL-2的促增殖反应性却显著降低.以siRNA适当下调IL-2Rα基因的表达则可显著提高激活的Th1细胞对IL-2的反应性.虽然激活后的na(i)ve CD4细胞对IL-2的反应性明显增加,但却不与CD25的含量及激活度正相关.最高的IL-2反应性出现在低度激活的CD4细胞中.结论 CD25在激活后的Th细胞中显著增多,并可通过自身数量的变化来调节所在细胞对IL-2的促增殖反应性.适度高表达的CD25可使靶细胞具有最高的IL-2反应性,过度表达的CD25则可导致对IL-2反应性的降低.