Cytokine production profile of splenocytes derived from zymosan A-treated SKG mice developing arthritis

Objective SKG mice have a point mutation of the zeta-associated protein of 70 kD (ZAP-70) and spontaneously develop a severe polyarthritis in the conventional condition, whereas they are healthy under the specific pathogen free (SPF) condition. The purpose of this study was to investigate the cytokine production from splenocytes in SKG mice developing arthritis under the SPF condition. Material SKG and BALB/c mice were intraperitoneally injected with zymosan A under the SPF condition. Spleen was isolated 1, 2 or 8 weeks after the intraperitoneal injection of saline or zymosan A. Splenocytes were cultured with concanavalin A. Cytokine production and proliferation were measured 48 and 72 h after the culture. Results An intraperitoneal injection of zymosan A induced severe polyarthritis with increased levels of rheumatoid factor and interleukin 6 (IL-6) only in SKG mice. Splenocytes from SKG mice did not proliferate well maybe because of less productivity of IL-2. The IL-4 production from splenocytes of SKG mice was higher, while interferon-γ production was lower than those of BALB/c mice. An injection of zymosan A reduced the IL-4 production only in SKG mice. Conclusions SKG mice do not develop arthritis under the SPF condition possibly because of a low proliferative activity of T cells and Th2-predominance. Received 27 December 2005; returned for revision 7 February 2006; accepted by A. Falus 10 March 2006     

ELISPOT,MHC肽五聚体和ICCD三种检测特异性细胞免疫应答方法的比较研究

目的 比较三种特异性细胞免疫应答的检测方法，寻求一种简便、重复性好、易于质控的评价疫苗细胞免疫的检测方法。方法采用HIV DNA疫苗肌内注射BALB／c小鼠，第6周用艾滋病重组MVA痘苗病毒腹腔注射加强免疫，于第10天制备脾脏细胞悬液，并用酶联免疫斑点法（Enzymeunked Immune Spot，EusPOT）、MHC肽五聚体法和胞内细胞因子染色分析法（Intra—cellular cytokinede tection，ICCD）分别检测细胞免疫应答。结果 ELISPOT、MHC肽五聚体染色以及胞内细胞因子染色分析法检测疫苗组细胞免疫应答的阳性率分别为5／5、4／5和3／5；而且ELISPOT和MHC肽五聚体染色法之间有一定相关性（r=0、647），而ELISPOT和胞内因子染色法之间以及MHC肽五聚体染色和胞内因子染色之间无相关性。结论ELISPOT试验操作相对简单，灵敏度高、重复性好，是评价疫苗细胞免疫的有效方法。     

抗纤维化细胞因子对TGF-β1基因启动转录活性的影响

转化生长因子β1(transforming growth factor-β1)是一类现已明确的致纤维化细胞因子,具有广泛的生物学效应,对细胞外基质(ECM)基因表达、降解、细胞增殖分化、凋亡及免疫功能都具有重要调节作用。前期我们研究发现,TGF-β1启动调控序列中单核苷酸多态性(single nucleotide polymorphism,SNP)位点-509C>T与肝纤维化进展及血浆中TGF-β1浓度有明显的相关性。本研究旨在探讨抗纤维化细胞因子(IL-10、HGF、IFN-γ)对含TGF-β1基因-509C>T启动调控序列活性的影响。我们以特定-509C>T基因型患者DNA为模板,用PCR方法扩增得到一对长度为2.14kb(-1328~+812)含有-509C>T变异的TGF-β1上游基因片段,并将其与不含启动子的pCAT3-enhancer报告基因载体重组,构建重组体phT-GF2.14C和phTGF2.14T。用脂质体转染法将两种重组体分别转染至正常人肝脏细胞中,分别用IL-10(4ng/ml)、HGF(10ng/ml)、IFN-γ(20ng/ml)干预转染后细胞。ELISA法测定转染细胞的报告基因CAT活性。结果表明:肝细胞转染重组体phTGF2.14C细胞的CAT活性明显高于转染重组体phTGF2.14T(t=12.5882,P=0.0002)。IFN-γ对TGF-β1基因启动子phTGF2.14C、phTGF2.14T均具有显著抑制作用。细胞因子IL-10和HGF对其调控作用不显著。TGF-β1基因-509C>T中C等位基因可明显增强TGF-β1基因上游启动调控序列的转录活性,IFN-γ作为一种抗纤维化细胞因子在基因转录水平对含有两种等位基因-509C>T的TGF-β1基因上游启动调控序列均具有抑制作用。而作为抗纤维化细胞因子的IL-10与HGF在2.14Kb(-1328~+812)区域内对TGF-β1基因上游启动调控序列的作用不显著。     

Nasal tolerance in experimental autoimmune myasthenia gravis (EAMG): induction of protective tolerance in primed animals

Nasal administration of μg doses of acetylcholine receptor (AChR) is effective in preventing the development of B cell-mediated EAMG in the Lewis rat, a model for human MG. In order to investigate whether nasal administration of AChR modulates ongoing EAMG, Lewis rats were treated nasally with AChR 2 weeks after immunization with AChR and Freund's complete adjuvant. Ten-fold higher amounts of AChR given nasally (600 μg/rat) were required to ameliorate the manifestations of EAMG compared with the amounts necessary for prevention of EAMG. In lymph node cells from rats receiving 600 μg/rat of AChR, AChR-induced proliferation and interferon-gamma (IFN-γ) secretion were reduced compared with control EAMG rats receiving PBS only. The anti-AChR antibodies in rats treated nasally with 600 μg/rat of AChR had lower affinity, reduced proportion of IgG2b and reduced capacity to induce AChR degradation. Numbers of AChR-reactive IFN-γ and tumour necrosis factor-alpha (TNF-α) mRNA-expressing lymph node cells from rats treated nasally with 600 μg/rat of AChR were suppressed, while IL-4, IL-10 and transforming growth factor-beta (TGF-β) mRNA-expressing cells were not affected. Collectively, these data indicate that nasal administration of AChR in ongoing EAMG induced selective suppression of Th1 functions, i.e. IFN-γ and IgG2b production, but no influence on Th2 cell functions. The impaired Th1 functions may result in the production of less myasthenic anti-AChR antibodies and contribute to the amelioration of EAMG severity in rats treated with AChR 600 μg/rat by the nasal route.     

脐血来源的树突状细胞增强CIK细胞的杀伤作用

为确认体外诱导出的成熟脐血来源树突状细胞 (CBDC )可以引发强大抗肿瘤免疫反应 ,CBDC培养 12d后用电镜分析形态 ,用流式细胞仪检测其表型。在不同培养时间 ,用3 H TdR掺入法检测CBDC和细胞因子诱导杀伤细胞 (CIK )的扩增功能 ;用MTT法检测被CBDC激活的CIK抗肿瘤活性。结果表明 ,体外诱导出形态典型的DC ,高表达主要组织相容性抗原I、II类分子、CD5 4 ,也表达CD80、CD83、CD1a,不表达CD6 8。体外培养 12d成熟的CBDC ,能使CIK以最高的比率扩增 ,2种细胞最佳混合比为 1∶10时被激活的CIK杀伤BEL 74 0 2肝癌细胞的功能最强 ,最佳效靶比为 80∶1     

Enhanced clearance of Candida albicans from the oral cavities of mice following oral administration of Lactobacillus acidophilus

Orally administered live Lactobacillus acidophilus was assessed for its capacity to enhance clearance from the oral cavity of DBA/2 mice shown previously to be 'infection prone'. L. acidophilus fed to DBA/2 mice significantly shortened the duration of colonization of the oral cavity compared to controls. Enhanced clearance of Candida albicans correlated with both early mRNA gene expression for interleukin (IL)-4 and interferon (IFN)-gamma and expression of their secreted products in cultures of cervical lymph nodes stimulated with Candida antigen. In addition rapid clearance correlated with higher levels of IFN-gamma and nitric oxide in saliva. Delayed clearance, less pronounced levels of the cytokine response, saliva IFN-gamma and nitric oxide, and later mRNA expression for IL-4 and IFN-gamma relative to feeding with the L. acidophilus isolate were noted in mice fed a different Lactobacillus isolate (L. fermentum). These observations indicate significant variations in individual isolates to activate the common mucosal system.     

In vitro immunomodulatory properties of tucaresol in HIV infection

The immunomodulatory properties of tucaresol (compound 589C80) were tested on in vitro antigen- and mitogen-stimulated proliferation and cytokine production by peripheral blood mononuclear cells (PBMC) of HIV-infected individuals and healthy controls (HC). Results showed that tucaresol: (1) increases influenza A virus-, gp 160 peptide-, and HLA alloantigen-stimulated proliferation as well as interleukin (IL)-2 and interferon gamma (IFN gamma) production by PBMC of HIV-infected individuals with higher CD4 counts (>500/microl) but had only a marginal immunomodulatory effect on PBMC of patients with lower CD4 counts (<500/microl); (2) did not modify IL-10 production; (3) augmented CD25 expression on mitogen-stimulated T cells of HC but not of HIV-infected individuals; and (4) marginally increased CTL activity. The immunomodulatory properties of tucaresol were confirmed by PCR analyses; additional data showed that tucaresol costimulated CD3-dependent triggering of T cells and that this stimulation was independent of CD28 costimulation. The immunomodulatory effects of tucaresol on T cell functions are characterized by a bell-shaped dose response curve; the action of the compound is optimal in the 100 to 300 microM range. Analyses of mitogen-stimulated apoptosis demonstrated that the lack of effect of tucaresol at higher doses is not the result of increased cell death, suggesting a role of functional impairment. These data confirm that tucaresol can stimulate T helper cell function and enhance the production of type 1 cytokines, thus eliciting cell-mediated immunity, and warrant its potential utility in the therapy of HIV infection.     

细胞因子对肾小球系膜细胞合成PAF的影响

本文首先建立了血小板活化因子（ＰＡＦ）的生物活性检测法，并通过体外细胞培养技术，测定了肾小球系膜细胞在经ＬＰＳ、ＩＬ-１β、ＩＬ-６和ＴＮＦα的短暂刺激后，其培养上清中ＰＡＦ的活性。结果发现，它们均能诱导系膜细胞合成和分泌ＰＡＦ，ＩＬ-１β、ＩＬ-６和ＴＮＦα的诱生作用并呈一定的剂量依赖关系。实验提示上述因子在肾小球免疫病理损伤中，除直接作用外，也可通过诱生ＰＡＦ而间接发挥作用。应用ＰＡＦ拮抗剂来阻断这一途径，可能具有一定的临床应用价值。     

Stability of Th1 and Th2 populations

Using an in vitro model for the development of IFN-y-producIng(Th1) and IL-4-produclng (Th1) cells from CD4 T lymphocytesexpressing a transgenlc TCR, we show that IL-12 and IL-4 arethe most potent stimuli for the differentiation of naive T cellsto effector populations. When combinations of cytokines arepresent during T cell priming, the effect of IL-4 Is dominant.Furthermore, differentiated Th1 cells can be converted intoIL-4 producers by exposure to IL-4, but the Th2 phenotype Isnot reversible. The stability of Th2 populations may limit theability to regulate Th2-domlnant responses In pathologic situations.