IL-23与IL-12诱导NK细胞功能的异同及机制初探

目的探讨细胞因子IL-23与IL-12对NK细胞功能的影响及可能的机制。方法密度梯度离心法分离人外周血单个核细胞(PBMCs)或磁珠纯化NK细胞,不刺激或用IL-23或IL-12刺激,用流式细胞术和ELISA法检测NK细胞产生IFN-γ的情况;以K562或Jurkat细胞作为靶细胞,用流式细胞术检测NK细胞的杀伤功能并分析NK细胞在不同的刺激条件下杀伤相关分子的表达情况及pSTAT的表达情况。结果与未刺激组相比,IL-23和IL-12均可以诱导NK细胞呈剂量和时间依赖方式产生IFN-γ;但IL-12而非IL-23可以增强NK细胞对靶细胞K562或Jurkat细胞的杀伤功能。进一步研究表明,IL-12而非IL-23可以诱导杀伤相关分子TRAIL及CD107a/b的表达。此外,IL-12诱导NK细胞表达更高水平的pSTAT4,而IL-23诱导NK细胞表达更高水平的pSTAT3。结论与IL-12相比,IL-23亦可以诱导NK细胞产生细胞因子但不能增强NK细胞的杀伤功能,IL-23不能诱导杀伤相关分子TRAIL及CD107a/b的表达,IL-23可以诱导低水平的pSTAT4但高水平的pSTAT3的表达。     

热灭活白念珠菌通过Dectin-1诱导外周血单个核细胞表达IL-12和IFN-γ

为研究Dectin-1在热灭活白念珠菌刺激外周血单个核细胞(PBMC)免疫应答中的作用。我们用不同浓度昆布多糖(Dectin-1封闭剂)与PBMC共培养1 h后,再用热灭活白念珠菌刺激PBMC 4 d;同时用不同剂量的Dectin-1激活剂酵母聚糖(zymosan)刺激PBMC 4 d,收集培养液上清,经ELISA检测IL-12和IFN-γ水平。结果发现,昆布多糖可以部分抑制热灭活白念珠菌刺激PBMC合成IL-12和IFN-γ的能力,酵母聚糖可以诱导PBMC合成IL-12和IFN-γ。因此,Dectin-1是介导热灭活白念珠菌诱导PBMC产生IL-12和IFN-γ的受体之一。     

类风湿关节炎患者单个核细胞IL-23的表达及意义

目的:通过分析比较类风湿关节炎(Rheumatoid Arthritis,RA)患者血清和外周血单个核细胞(Peripheral bloodmononuclear cell,PBMC)IL-23的表达,探讨其在RA发病过程中的作用,以期为治疗开辟新途径。方法:应用ELISA方法检测RA、骨性关节炎(Osteoarthritis,OA)及正常对照组血清中IL-23和TNFα-蛋白水平,采用RT-PCR法测定各组PBMC中IL-23p19mRNA的表达,并作血清IL-23含量、PBMC IL-23p19mRNA的表达与血清TNFα-水平的相关分析。结果:RA组血清IL-23水平高于正常对照组(P=0.001),其他组间无统计学差异(分别为P=0.122,P=0.127);而各组血清TNFα-的水平均具有统计学差异,RA和OA组均高于对照组(P=0.000,P=0.042),RA组也高于OA组(P=0.013);RA组IL-23p19mRNA的表达高于OA和正常对照组(P=0.000,P=0.000),而OA组与正常对照组差异无统计学意义(P=0.628);血清中IL-23和TNFα-的相关性无统计学差异(r=0.212,P=0.262),而PBMC中IL-23p19mRNA的表达与血清TNFα-呈正相关关系(r=0.392,P=0.032)。结论:IL-23在RA患者PBMC中高表达,在RA的炎性发展过程起到了重要作用。     

IL-4、IL-10和抗IL-12受体β1 mAb抑制IL-23诱导正常人记忆T细胞 IFN-γ产生

目的 探讨重组人白介素23（IL-23）是否能够诱导正常人T细胞IFN-γ的产生,作用的靶细胞亚群和调节因素。方法 正常人PBMC在抗CD3（anti-CD3）单克隆抗体或anti-CD3和抗CD28（anti-CD28）单克隆抗体刺激的条件下与IL-23进行培养,采用酶联免疫吸附试验（ELISA）检测细胞培养液中IFN-γ的水平;同时采用流式细胞仪,在单个细胞水平上分析IL-23诱导PBMC IFN-γ表达的T细胞亚群。结果 在未经任何刺激的情况下,PBMC产生很低或不产生IFN-γ。IL-23呈剂量依赖方式促进由anti-CD3活化的PBMC IFN-γ产生。细胞亚群分析的结果表明,IL-23诱导记忆CD4^＋和CD8^＋T细胞表达IFN-γ,对活化的CD4^＋T细胞作用较为明显。Th2细胞因子（IL-4、IL-10）和抗IL-12受体β1 mAb（IL-12Rβ1）抑制IL-23诱导T细胞IFN-γ产生。结论 IL-23促进活化的记忆CD4^＋和CD8^＋T细胞IFN-γ的产生。Th2细胞因子和抗IL-12Rβ1 mAb抑制由IL-23诱导IFN-γ产生,提示这些细胞因子和抗体对IL-23引起的自身免疫病具有拮抗作用。     

脐血单个核细胞表达IL-12、IFN-γ及其mRNA的观察

白细胞介素１２（ＩＬ－１２）的主要作用是促进ＴＨ１细胞和自然杀伤细胞（ＮＫ）产生γ－干扰素（ＩＦＮ－γ）,介导细胞免疫。脐血单个核细胞（ＣＢＭＣ）产生ＩＬ－１２的能力鲜见报道。重组ＩＬ－１２（ｒＩＬ－１２）在体外能促进新生儿ＣＤ４＋Ｔ细胞产生ＩＦＮ－...     

绿脓杆菌制剂与IL-12在诱导人NK细胞IFN-γ产生中的协同作用

探讨绿脓杆菌制剂(piliated Pseudomonas Aeruginosa,PPA)与IL-12协同诱导人PBMC和NK细胞IFN-γ的产生。分离健康人PBMC和纯化NK细胞分别与培养液、PPA、IL-12或PPA+IL-12共同培养,利用酶联免疫吸附法(ELISA)检测无细胞培养上清中IFN-γ的水平。同时采用流式细胞仪在单个细胞水平上分析PPA和IL-12诱导IFN-γ产生的淋巴细胞亚群。结果显示,单独应用亚适剂量的IL-12或PPA刺激人PBMC或纯化NK细胞,不能诱导或只能诱导低水平IFN-γ的产生。当PPA和IL-12共同与人PBMC或纯化NK细胞孵育后,PPA呈时间和剂量依赖性与IL-12协同诱导PBMC和纯化NK细胞产生大量IFN-γ。细胞亚群分析的结果表明,PPA和IL-12协同诱导CD56+NK细胞产生IFN-γ,但对CD4+T和CD8+T细胞无明显作用。PPA与IL-12协同促进NK细胞IFN-γ的产生,提示PPA和IL-12能直接刺激NK细胞发生免疫应答。     

IL-23的研究进展

IL 2 3是新近发现的一种细胞因子 ,主要来源于活化的单核巨噬细胞和B细胞。它具有多种生物学功能 ,能促进T细胞尤其是CD4 T细胞增殖 ,促进T细胞、抗原提呈细胞产生IFN γ与IL 12 ,对树突状细胞的共刺激功能起调节作用 ,具有抗肿瘤和抗转移活性 ,而且与自身免疫和炎症反应疾病密切相关。     

IL-12基因不同亚基真核表达载体的构建及表达

目的:克隆并构建含人白介素12(hIL-12)基因p35、p40不同亚基的真核表达载体,瞬时转染真核细胞并诱导IL-12的表达。方法:人单核细胞白血病细胞株(THP-1)和人白血病细胞株(HL-60),经DMSO、IFN-γ和LPS诱导后,用RT-PCR及SOEPCR扩增IL-12p40、p35及p40-p35融合基因;并构建pcDNA-p35、pcDNA-p40及pcDNA-IL-12真核表达载体。以3种重组质粒分别瞬时转染COS-7细胞后,通过RT-PCR及ELISA法检测目的基因的表达。结果:经诱导后,从HL-60细胞中扩增到IL-12p40和p35基因片段;但从THP-1细胞中只扩增到p35基因片段,未能扩增到p40基因片段;经酶切鉴定、PCR扩增及序列测定表明pcDNA-p35、pcDNA-p40及pcDNA-IL-12真核表达质粒构建成功;并在COS-7细胞中可检测到IL-12的表达。结论:含hIL-12基因不同亚基的真核表达质粒的成功构建,对进一步研究IL-12在免疫应答中的调节作用以及作为免疫佐剂改善BCG免疫保护效果的研究奠定了基础。     

Profiles of IFN-gamma and its regulatory cytokines (IL-12, IL-18 and IL-10) in peripheral blood mononuclear cells from patients with multidrug-resistant tuberculosis

This study investigated the profiles of IFN-gamma and its regulatory cytokines (IL-12, IL-18 and IL-10) in response to a purified protein derivative (PPD) antigen in peripheral blood mononuclear cells (PBMC) from 18 HIV-negative patients with multidrug-resistant tuberculosis (MDRTB), and compared them with those from 19 healthy tuberculin reactors (HTR). ELISA results showed that following stimulation with PPD, IFN-gamma production was significantly reduced, whereas production of both IL-18 and IL-10 was significantly elevated in MDRTB patients compared with HTR. Three out of 18 patients with MDRTB of greater than 4 years duration showed significantly elevated IL-12 p70 production, induced by in vitro PPD stimulation of their PBMC, when compared with data from HTR. However, when taken as a group, MDRTB patients were similar to HTR in their IL-12 p70-producing capacity. IL-12 p70 protein paralleled IL-12 p40 protein expression. In addition, the production of IL-12 p40 was significantly correlated with IL-10 in all patients, but was not correlated with IFN-gamma. Neutralization of IL-10 increased IL-12 p40 about twofold, but did not significantly alter IFN-gamma induction in MDRTB. IFN-gamma in MDRTB was highly correlated with lymphoproliferation and CD4 counts, but was not correlated with IL-12, IL-18 or IL-10 production. Our findings suggest that patients with MDRTB have dysregulated IL-12, IL-18 and IL-10 production during Mycobacterium tuberculosis infection, and the cytokine profiles are similar to those in patients with drug-sensitive advanced TB previously reported in the literature. In addition, IL-10 may not have a dominant role in defective IFN-gamma production in patients with MDRTB.     

脂多糖和金黄色葡萄球菌对IL-23、IL-12表达的调控

目的：检测脂多糖（LPS）和金黄色葡萄球菌（SAC）对人外周血单个核细胞（PBMC）IL-23和IL-12各亚基表达的调节作用并探索其作用机制。方法：用LPS和SAC直接刺激人PBMC，或用CD14抗体或p38丝裂原活化蛋白激酶（MAPK）抑制剂Mastoparan预处理PBMC后再予LPS和SAC刺激，半定量RT-PCR方法检测IL-23p19、IL-12p35和IL-12p40亚基的基因表达变化。结果：人PBMC组成性表达p19和p35，不表达p40。LPS和SAC可上调各亚基的表达。LPS诱导的IL-23和IL-12各亚基表达均需通过CDl4；CDl4仅部分参与SAC诱导的IL-12p40和p35表达上调，而与p19上调无关。LPS和SAC诱导的IL-23和IL-12各亚基表达均需要p38MAPK通路。结论：LPS和SAC刺激下IL-23和IL-12亚基表达及信号传导通路既有相似之处又有不同点，为单独或同时调控这两种因子的表达提供线索。     

白介素-12及白介素-23对胃癌组织中CD4^＋记忆T细胞的影响

目的:探讨胃癌组织中IL-12、IL-23对CD4+记忆T细胞(CD4+Tm)的影响.方法:ELISA检测TNM不同期胃癌组织匀浆中IL-12、IL-23含量;不连续密度梯度离心法分离胃癌组织中的肿瘤浸润淋巴细胞(TIL),流式细胞仪检测TIL中CD4+ Tm及其亚群TEM和TCM在不同期胃癌组织中的分布状况.结果:TNM-Ⅰ、Ⅱ期胃癌组织中IL-12含量差别不明显,但均显著高于TNM-Ⅲ、TNM-Ⅳ期;TNM-Ⅰ期胃癌组织中IL-23的含量高于TNM-Ⅱ、TNM-Ⅲ、TNM-Ⅳ期.胃癌TIL中CD4+ Tm及TEM比例随TNM分期增加逐渐降低,而TCM比例逐渐升高.结论:胃癌组织中IL-12、IL-23含量的变化与胃癌TNM分期有关,且影响胃癌TIL中CD4+记忆T细胞及其亚群TCM和TEM的分布.     

Monocytes are primed to produce the Th1 type cytokine IL-12 in normal human pregnancy: an intracellular flow cytometric analysis of peripheral blood mononuclear cells

This paper considers both monocytes and peripheral blood lymphocytes as potential targets for maternal immunological modulation in pregnancy. Peripheral blood mononuclear cells (PBMCs) from non-pregnant and normal pregnant donors were stimulated in vitro, and cytokine production detected intracellularly by flow cytometry. It was found that monocyte production of TNF-alpha was unaltered in pregnancy, while production of IL-12 was significantly enhanced. In contrast, production of the Th1 type cytokine IFN-gamma was suppressed in the lymphocyte subsets: CD4+ T helper cells and CD56+ NK cells. Production of the Th2 type cytokine IL-4 in CD4+ cells was not significantly altered in pregnancy. These data suggest that the concept that pregnancy is a 'Th2 phenomenon' cannot be generalized to the function of all aspects of maternal cellular immunity as, paradoxically, circulating monocytes are 'primed' to produce the Th1 cytokine IL-12. Furthermore, these data support the hypothesis that components of maternal innate immunity are activated in normal pregnancy.     

IL-12 inhibits in vitro immunoglobulin production by human lupus peripheral blood mononuclear cells (PBMC)

Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease characterized by polyclonal B cell activation and by the production of anti-double-stranded (ds) DNA antibodies. Given the inhibitory effects of IL-12 on humoral immune responses, we investigated whether IL-12 displayed such an activity on in vitro immunoglobulin production by SLE PBMC. Spontaneous IgG, IgG1, IgG2, IgG3 and IgM antibody production was dramatically reduced by addition of IL-12. These results were confirmed by Elispot assays detecting IgG- and anti-dsDNA-secreting cells. While IL-6 and TNF titres measured in PBMC supernatants were not modified by addition of IL-12, interferon-gamma (IFN-γ) titres were up-regulated and IL-10 production down-regulated. Since addition of IFN-γ did not down-regulate immunoglobulin production and since the inhibitory activity of IL-12 on immunoglobulin synthesis was not suppressed by anti-IFN-γ antibody, we concluded that the effect of IL-12 on immunoglobulin production was not mediated through IFN-γ. Our data also argue against the possibility that down-regulation of endogenous IL-10 production was responsible for the effect of IL-12. Thus, inhibition of IL-10 production by IFN-γ was not accompanied by inhibition of immunoglobulin production, and conversely, restoration of IL-10 production by anti-IFN-γ antibody did not suppress the inhibitory activity exerted by IL-12 on immunoglobulin production. Taken together, our data indicate that reduction of excessive immunoglobulin and anti-dsDNA antibody production by lupus PBMC can be achieved in vitro by IL-12, independently of IFN-γ and IL-10 modulation.     

Selective type IV phosphodiesterase inhibitors prevent IL-4-induced IgE production by human peripheral blood mononuclear cells

Background Selective type IV phosphodiesterase (PDE) inhibitors elicit anti-inflammatory and bronchodilatory activities in vitro and in vivo which suggest that these drugs could provide a new therapeutic approach for asthma treatment. Objective Regarding the role of IgE production in allergic and inflammatory reactions of the airways, we investigated the effect of selective PDE inhibitors on IL-4-driven IgE production by peripheral blood mononuclear cells (PBMC) or by purified B lymphocytes. Methods PBMC or purified B lymphocytes from non-allergic donors were stimulated for 13 days with IL-4 (100U/mL) in the presence or in the absence of selective PDE inhibitors. IgE production is evaluated by an ELISA technique. Results The selective PDE IV inhibitors, rolipram and Ro 20–1724 (10μM), inhibit lL-4-induced IgE production by PBMC. but not by purified B lymphocytes. No modification of the IgE production was noted with the selective PDE III inhibitors, milrinone and SK&F94-836, or the selective PDE V inhibitor, SK&F 96–231 (10 μM). Flow cytometry experiments showed that the effect of Rolipram could not be explained by the inhibition of the cell surface expression of the IL-4 receptor. Similarly, no significant effect of PDE IV inhibitors was observed on PHA-induced cell proliferation. The incubation of monocytes only with rolipram was sufficient to achieve a significant reduction of IgE production induced by IL-4. Conclusion Taken together, these results indicate that PDE IV inhibitors reduce lL-4-induced IgE production by PBMC and suggest that the inhibition of IgE production could be explained by a failure of monocytes to provide the necessary costimulatory signals.     

IFN-γ production in response to IL-18 or IL-12 stimulation by peripheral blood mononuclear cells of atopic patients

BACKGROUND: Several studies have shown that interleukin (IL)-4 and interferon-gamma (IFN-gamma) are important for the regulation of immunoglobulin E (IgE) production and that IL-18 and IL-12 induce IFN-gamma. OBJECTIVE: IFN-gamma production in response to IL-18 or IL-12 stimulation was investigated in peripheral blood mononuclear cells (PBMCs) of atopic patients with various levels of serum IgE. METHODS: Cytokine production from PBMCs was measured following stimulation with a non-specific stimulator (phytohemagglutinin: PHA), IL-18 or IL-12 in 12 healthy controls and 26 atopic patients with various serum IgE levels. RESULTS: IFN-gamma production by IL-18-stimulated PBMCs was positively correlated with IFN-gamma production by IL-12-stimulated PBMCs (P < 0.05). However some atopic patients showed discrepancy between the levels of IFN-gamma production stimulated by IL-12 and by IL-18. CONCLUSIONS: The results shown here suggest the presence of abnormalities in the IL-12 and/or IL-18 signalling pathways, such as genetic defects in the atopic patients.     

IL-12 and IL-23 modulate plasticity of FoxP3+ regulatory T cells in human Leprosy

Leprosy is a bacterial disease caused by M. leprae. Its clinical spectrum reflects the host’s immune response to the M. leprae and provide an ideal model to investigate the host pathogen interaction and immunological dysregulation. Tregs are high in leprosy patients and responsible for immune suppression of the host by producing IL-10 and TGF-β cytokines. In leprosy, plasticity of Tregs remain unstudied. This is the first study describing the conversion of Tregs into Th1-like and Th17-like cells using in vitro cytokine therapy in leprosy patients. Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA), rIL-12 and rIL-23 for 48 h. Expression of FoxP3 in CD4⁺CD25⁺ Tregs, intracellular cytokines IFN-γ, TGF-β, IL-10 and IL-17 in Tregs cells were evaluated by flow cytometry (FACS) after stimulation. rIL-12 treatment increases the levels of pStat4 in Tregs and IFN-γ production. In the presence of rIL-23, pStat3⁺ and IL-17A⁺ cells increase. rIL-12 and r—IL-23 treatment downregulated the FoxP3 expression, IL-10 and TGF-β production by Tregs and enhances the expression of co-stimulatory molecules (CD80, CD86). In conclusion rIL-12 converts Tregs into IFN-γ producing cells through STAT-4 signaling while rIL-23 converts Tregs into IL-17 producing cells through STAT-3 signaling in leprosy patients. This study may helpful to provide a new avenue to overcome the immunosuprression in leprosy patients using in vitro cytokine.     

Interleukin‐12 (IL‐12), but not IL‐23, induces the expression of IL‐7 in microglia and macrophages: implications for multiple sclerosis

Interleukin-12 (IL-12) p70 and IL-23 are bioactive cytokines and their biological functions are becoming clear. Increased expression of IL-7 in the central nervous system as well as in peripheral immune cells is associated with multiple sclerosis and experimental allergic encephalomyelitis. Here, we describe the induction of IL-7 in primary mouse and human microglia, BV-2 microglial cells, mouse peritoneal macrophages and astrocytes by IL-12p70. Interestingly, IL-12 strongly induced the expression of IL-7 whereas IL-23 and other p40 family members remained weak inducers of IL-7 in these cell types. Consistently, IL-12, but not IL-23 and other p40 family members, induced IL-7 promoter-driven luciferase activity in microglial cells. Among various stimuli tested, IL-12 emerged as the most potent stimulus followed by bacterial lipopolysaccharide and HIV-1 gp120 in inducing the activation of IL-7 promoter in microglial cells. Furthermore, increase in IL-7 mRNA expression by over-expression of IL-12p35 subunit, but not p40 and IL-23 p19 subunit, confirm that p35, but not p40 and p19, is responsible for the induction of IL-7. Finally, by using primary microglia from IL-12 receptor β1-deficient (IL-12Rβ1^−/−) and IL-12Rβ2^−/− mice, we demonstrate that IL-12 induces the expression of IL-7 in microglia and macrophages via both IL-12Rβ2 and IL-12Rβ1. These studies delineate a novel biological function of IL-12 that is absent in IL-23 and other p40 family members.