Human IgG anti-F(ab'')2 antibodies possess rheumatoid factor activity.

Individual preparations of affinity purified anti-F(ab')2 antibodies and anti-Fc antibodies isolated from the sera of patients with rheumatoid arthritis (RA), were examined for reactivity with the Fab and Fc fragments of human IgG. Western blot assays demonstrated specific interaction of affinity-purified anti-Fab antibodies with both Fab and Fc molecules. Approximately one-half of the anti-Fab antibody preparations studied contained IgG antibodies reactive with Fab and Fc fragments in ELISA, suggesting the existence of naturally occurring epibody-like autoantibodies in these patients. Thirteen of 14 affinity-purified anti-Fc antibody preparations contained IgG cross-reactive with Fab molecules in ELISA. Double-adsorption assays on affinity columns demonstrated that a minimum of 14%, and possibly as much as 50%, of the IgG anti-Fab antibodies reacted with the Fc of IgG. Conversely, a minimum of 12%, and possibly as much as 70%, of the IgG anti-Fc antibodies reacted with IgG Fab molecules. Anti-Fab antibodies isolated from non-RA individuals also exhibited anti-Fc reactivity in ELISA, demonstrating the presence of these dual-reactive antibodies in other autoimmune and normal individuals. These studies establish the presence of naturally occurring IgG autoantibodies reactive with both the Fab and Fc fragments of human IgG. Their existence emphasizes the potential of anti-immunoglobulin antibodies to recognize a multiplicity of antigens, possibly including other members of the immunoglobulin supergene family.     

三磷酸肌醇在IL—2诱导的T细胞增殖分化中的信息传递作用

用不同浓度的IL-2刺激静息T淋巴细胞,其细胞内IP_3无明显改变,但ConA刺激则使IP_3增加45%。在IL-2依赖性T细胞,IL-2R表达率达83%,IL-2刺激时IP_3的变化依浓度不同而异,10u—50u/ml的IL-2使IP_3增高,以50u/ml最为显著,增加60%,但100u/ml IL-2及ConA不改变胞内IP_3的浓度。IL-2R封闭后的T淋巴细胞在IL-2刺激时IP_3的增加明显减弱。这些结果提示:IP_3作为细胞内的第二信使介导了IL-2诱导的T细胞的增殖反应,这种作用与IL-2的剂量及IL-2R表达有密切的关系。     

Biochemical characterization of I-Ak proteins from mutant antigen-presenting B-cell--B-lymphoma hybridomas

Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure.     

慢性乙肝患者血清趋化因子RANTES水平与肝功能生化指标等的相关性研究

Objective To investigate the level of the serum chemokine RANTES and its correlation with serum biochemical indices of liver function test, HBeAg and HBV DNA load in patients with chronic hepatitis B.Methods 144 patients with chronic hepatitis B (observed group) and 18 normal cases (control group) were enrolled in this study. The serum level of chemokine RANTES was detected with an ABC-ELISA assay. Statistical analysis was performed on the software of SPSS13.0. Results The serum chemokine RANTES level in the observed group (3930.12 ng/ml±2856.96) ng/ml was significantly higher than that in the control group (329.46 ng/ml±152.23) ng/ml. The results from the observed group indicated the positive correlation of serum RANTES level with indices of liver function test, including ALT (r=0. 197, P=0.018), AST(r=0.239, P=0.004) and TBil (r=0.316, P=0.001), but did not with PTA (r=-0.078, P=0.357). Neither difference of serum chemokine RANTES level between HBeAg-positive group and HBeAg-negative group nor that between high HBV DNA load group (≥105 copies/ml) and low HBV DNA load group (< 105 copies/ml) were statistically significant (P=0.407 and 0.185, respectively). Conclusions Serum chemokine RANTES level in patients with chronic hepatitis B elevates significantly and is not affected by HBeAg or HBV DNA load. Its positive correlation with indices of liver function test indicates that RANTES might play an important rule in the pathogenesis of chronic hepatitis B.     

树突状细胞负载肝癌抗原肽疫苗体外诱导特异性免疫学反应的研究

目的：研究树突状细胞(dendritic cell，DC)负载肝癌抗原肽EPVTKAEML体外诱导特异性CTL的能力及其抑癌效果。方法：用顺序特异引物聚合酶链反应技术(PCR—SSP)选择HLA—B7表型供者，从脾组织中分离、培养DC-EPVTKAEML特异性CTL。用^51Cr释放法检测CTL的杀伤活性，并用抗HLA-1分子单抗(mAb)进行杀伤抑制实验。结果：找到4例HLA-B7杂合子供者，用DC负载HLA-B7限制的抗原肽EPVTKAEML可诱导特异性CTL反应，对肝癌细胞HHCC有较强的杀伤作用。结论：DC负载抗原肽EPVTKAEML在体外可诱发较强的特异性免疫反应。     

Human serum IgE-mediated mast cell degranulation shows poor correlation to allergen-specific IgE content

BACKGROUND: Although allergen-specific IgE content in serum can be determined immunochemically, little is known about the relationship between this parameter and the strength of the degranulation response upon allergen triggering. OBJECTIVES: Analyse the degranulation capacity of immunochemically defined purified and serum IgE after challenge with anti-IgE or allergen using a rat mast cell line (RBL) transfected with the alpha-chain of the human high-affinity IgE receptor (FcepsilonRI). METHODS: Purified IgE specific for 4-hydroxy-3nitrophenylacetyl, purified IgE of unknown specificity, and sera from allergic patients sensitive to Dermatophagoides pteronyssinus and Dactylis glomerata were assessed. Degranulation was measured by a beta-hexosaminidase release assay after anti-IgE or allergen-specific challenge. RESULTS: For purified monoclonal IgE a significant correlation (r = 0.97) was found between the proportion of bound allergen-specific IgE and the strength of the degranulation response. In contrast, no correlation (r = 0.27) was detected after sensitization with serum IgE. CONCLUSION: Our studies demonstrate that mast cell activation mediated through IgE from allergic patients is a result of complex relationships that are not only dependent on allergen-specific IgE content but also relate to the capacity to efficiently sensitize and trigger the signalling responses that lead to degranulation.     

Galectin-3与CDC25B在胃癌中的表达及意义

目的 探讨半乳糖凝集素3 mRNA(Galectin-3)和细胞分裂周期蛋白25B mRNA(cell division cycle 25B,CDC25B)在胃癌中的表达及其与临床病理参数及预后的关系.方法 应用组织微阵列技术和原位杂交法检测220例胃癌组织和31份正常胃黏膜组织中Galectin-3 mRNA和CDC25B mRNA 的表达情况.结果 220例胃癌中Galectin-3 mRNA和CDC25B mRNA的阳性表达率分别为58.6%、54.1%;Galectin-3 mRNA表达与肿瘤大小、TNM(tumor,lymph node,metastasis)分期、浸润深度、脉管侵犯、淋巴结转移及远处转移呈正相关;CDC25B mRNA表达也与肿瘤大小、TNM分期、脉管侵犯、淋巴结转移及远处转移呈正相关;Galectin-3 mRNA表达与CDC25B mRNA表达呈正相关;Galectim3 mRNA和CDC25B mRNA阳性表达病例的平均生存时间和5年生存率均明显低于阴性表达的病例.结论 Galectin-3 和CDC25B基因的表达促进了胃癌的发生和发展,是指导临床治疗及评估预后的有效指标.     

ST2作为Th2细胞亚群标志以及其与支气管哮喘的关系的研究

各自主要分泌IFN γ和IL 4的Th1和Th2亚群 ,与临床疾病的关系十分密切。如何从表面标志上加以区分是一项迫切需要解决的问题。ST2是近年来提出的Th2细胞的稳定标志物。本工作在体外成功地诱导人脐带血T细胞向Th1或Th2分化的基础上 ,应用逆转录PCR分析了ST2mRNA的表达特点。证实ST2在人Th2细胞上的选择性表达。为了探索ST2、Th2与支气管哮喘的关系 ,本工作进一步检测了正常人和支气管哮喘患者外周血单个核细胞中 β actin、ST2以及IFN γ和IL 4的mRNA水平。结果显示 :支气管哮喘患者ST2mRNA水平升高 ,IL 4水平也明显升高 ,但IFN γ无变化。这提示ST2作为Th2细胞的标志物 ,有可能成为Th2极化性疾病如哮喘发病机制研究的一个参考性标志 ,至于ST2是否有可能作为治疗的靶分子 ,有待进一步探讨     

Correlations of Soluble Interleukin-2 and Tumor Necrosis Factor Type II Receptors with Immunologic and Virologic Responses Under HAART

We assessed the correlations between some plasma markers of immune activation (soluble receptors of interleukin 2 (sIL2-R) and TNFp75 (sTNFII-R) and usual markers of HIV infection in patients treated with protease-inhibitors (PI). Forty-six PI-naive HIV-1-infected adults were included in a 1-year prospective cohort from the initiation of a PI-containing regimen (M0). Measurements of CD4+cell count, plasma HIV-RNA, sIL2-R and sTNFII-R were performed at M0, M6, and M12. The evolution of sIL2-R from baseline to M12 was significantly different between immunological responders (IR) (CD4+count above 200/mm³ for subject having less than 200 CD4 +/mm³ at inclusion, or increase of at least 50 CD4+/mm³ for others) (58 UI/ml) and non-IR (+28 UI/ml) (P =0.01). The evolution of sTNFII-R between M0 and M12 was significantly different between virological responders (VR) (plasma HIV-1 RNA less than 500 copies/ml at M12) (–2.5 ng/ml) and non-VR (+0.2 ng/ml) (P =0.02). Our study shows significative correlations between the evolutions of soluble interleukin-2 and TNFR-II receptors and those of CD4+T-lymphocytes or HIV-RNA responses in patients under HAART.