Human TSLP promotes CD40 ligand-induced IL-12 production by myeloid dendritic cells but maintains their Th2 priming potential

Interleukin-4 (IL-4), a major T-helper type 2 (Th2) cytokine, primes dendritic cells (DCs) for IL-12 production, suggesting a negative feedback loop to prevent dysregulated Th2 inflammation, such as allergy. We previously showed that human thymic stromal lymphopoietin (TSLP), highly expressed by keratinocytes of atopic dermatitis, activates CD11c(+) DCs to induce the differentiation of naive CD4(+) and CD8(+) T cells into proallergic effectors. Here we show that TSLP primes DCs to produce large amounts of IL-12 after CD40 ligand stimulation, similar to IL-4 priming of DCs. In contrast to IL-4 priming, DCs activated with TSLP and CD40 ligand induce the differentiation of naive CD4(+) T cells into effectors producing both Th1 and Th2 cytokines, a unique profile that is reminiscent of the late phase of allergy. Thus, TSLP is a major regulatory cytokine for IL-12 production by DCs, and TSLP-activated DCs could promote the persistence of Th2 inflammation even in the presence of IL-12-inducing signals.     

IL-1 family members and STAT activators induce cytokine production by Th2, Th17, and Th1 cells

Expression of T1ST2, the IL-33R, by Th2 cells requires GATA3. Resting Th2 cells express little GATA3, which is increased by IL-33 and a STAT5 activator, in turn increasing T1ST2 from its low-level expression on resting Th2 cells. Th2 cells that have upregulated T1ST2 produce IL-13, but not IL-4, in response to IL-33 plus a STAT5 activator in an antigen-independent, NF-κB-dependent, cyclosporin A (CsA)-resistant manner. Similarly, Th17 cells produce IL-17A in response to IL-1β and a STAT3 activator and Th1 cells produce IFNγ in response to IL-18 and a STAT4 inducer. Thus, each effector Th cell produces cytokines without antigenic stimulation in response to an IL-1 family member and a specific STAT activator, implying an innate mechanism through which memory CD4 T cells are recruited by an induced cytokine environment.     

初发系统性红斑狼疮患者Th1/Th2及其调控因子IL-10 IL-12基因研究

目的：探讨初发系统性红斑狼疮（SLE）病人Th1/Th2分布及其调控细胞因子、细胞因子受体基因表达的差异。方法：运用三色荧光标记法流工细胞术检测42例未红药物治疗初发狼疮病人，T细胞亚群分布，并以10名正常人作对照；同时运用ABI－7700实时监测定量PCR法检测其中38例病人和28名正常人IL－10／IL－12 mRNA及其受体表达的差异。结果：①初发SLE病人Th1较正常人明显减低（P＜0．05）；但Th1/Th2无显著性改变。②与正常组相比，SLE组病人IL－10mRNA表达差异无显著性，但IL－10R表达明显升高（P＜0．05）；SLE组病人IL－12mRNA及其受体表达较正常人明显降低（P均＜0．05）。③红斑组病人Th1/Th2、IL－12p35较正常组降低（P均＜0．05）；IL－10R较正常组显著增高IP＜0．05）。④RNP阳性组病人IL－10、IL－12p40较正常组升高，IL－2p35较正常组降低（P均＜0．05）。结论：SLE是一种以Th1细胞下降，Th2细胞相对占优势的免疫介导的自身免疫性疾病，源于诱导向Th1细胞分化的IL－12及其受体养活和细胞因子间失衡所致。     

HIV-1 exposed dendritic cells show increased pro-inflammatory cytokine production but reduced IL-1ra following lipopolysaccharide stimulation.

OBJECTIVES: Dendritic cells (DC) are potential first target cells in sexually transmitted HIV-1 infection. They are also considered to be central in the activation of naive T cells, which thereupon can become permissive for HIV-1. In addition, activated DC express effector molecules, which likely contribute to the direction of T helper (Th1/Th2)-specific immune responses. METHODS: The capacity of cytokine and chemokine production in in vitro DC infected and uninfected with HIV-1 was assessed by enzyme-linked immunosorbent assay (ELISA) and by in situ immunocytochemical detection at the single cell level. Fluorescent in situ 5'-nuclease assay (FISNA) was used for quantitative evaluation of HIV-1 gag-positive cells. RESULTS: Macrophage-tropic HIV-1 effectively infected 20-40% of in vitro cultured DC. However, this activity alone did not induce detectable cytokine or chemokine protein expression in DC. In contrast, lipopolysaccharide (LPS) stimulation of these HIV-1-infected DC resulted in a significantly increased level of cells producing tumour necrosis factor alpha (TNF-alpha) and interleukin (IL) 1beta but reduced frequencies of cells producing IL-1 receptor antagonist (IL-1ra) compared with the LPS-stimulated but uninfected DC cultures (P < 0.05). Furthermore, an extensive production of the beta-chemokines [RANTES, macrophage inflammatory proteins (MIP) 1alpha and 1beta] was detected in DC in response to both LPS and HIV-1 plus LPS. CONCLUSIONS: These findings indicate that HIV-1 infected DC may have an increased proinflammatory activity. Elevated production of cytokines such as TNF-alpha and IL-1beta and reduced IL-1ra may contribute to enhanced replication of HIV-1 in bystander T cells. Gram-negative bacterial infection and gut-associated bacterial translocation in HIV-1-infected individuals may also result in endotoxin-mediated reactivation of HIV-1 in bystander CD4 CD45RO T cells caused by the increased production of proinflammatory cytokines in DC.     

HIV-1-infected monocyte-derived dendritic cells do not undergo maturation but can elicit IL-10 production and T cell regulation

Dendritic cells (DCs) undergo maturation during virus infection and thereby become potent stimulators of cell-mediated immunity. HIV-1 replicates in immature DCs, but we now find that infection is not accompanied by many components of maturation in either infected cells or uninfected bystanders. The infected cultures do not develop potent stimulating activity for the mixed leukocyte reaction (MLR), and the DCs producing HIV-1 gag p24 do not express CD83 and DC-lysosome-associated membrane protein maturation markers. If different maturation stimuli are applied to DCs infected with HIV-1, the infected cells selectively fail to mature. When DCs from HIV-1-infected patients are infected and cultured with autologous T cells, IL-10 was produced in 6 of 10 patients. These DC-T cell cocultures could suppress another immune response, the MLR. The regulation was partially IL-10-dependent and correlated in extent with the level of IL-10 produced. Suppressor cells only developed from infected patients, rather than healthy controls, and the DCs had to be exposed to live virus rather than HIV-1 gag peptides or protein. These results indicate that HIV-1-infected DCs have two previously unrecognized means to evade immune responses: maturation can be blocked reducing the efficacy of antigen presentation from infected cells, and T cell-dependent suppression can be induced.     

Th2 polarization by Der p 1--pulsed monocyte-derived dendritic cells is due to the allergic status of the donors

The polarization of the immune response toward a Th2 or a Th1 profile can be mediated by dendritic cells (DCs) following antigen presentation and interaction with T cells. Costimulatory molecules such as CD80 and CD86 expressed by DCs, the polarizing cytokine environment during DC--T-cell interaction, and also the nature of the antigen are critical in the orientation of the immune response. In this study, the effect of the cysteine protease Der p 1, one of the major allergens of the house dust mite Dermatophagoides pteronyssinus, on these different parameters was evaluated comparatively on monocyte-derived DCs obtained from healthy donors, from pollen-sensitive patients, or from patients sensitive to Dermatophagoides pteronyssinus. Results showed that Der p 1 induced an increase in CD86 expression only on DCs from house dust mite--sensitive patients. This was also associated with a higher capacity to induce T-cell proliferation, a rapid increase in the production of proinflammatory cytokines, tumor necrosis factor--alpha and interleukin (IL)-1 beta, and the type 2 cytokine IL-10. No changes in the release of IL-12 p70 were induced by Der p 1. Finally, purified T cells from house dust mite-sensitive patients stimulated by autologous Der p 1--pulsed DCs preferentially produced IL-4 rather than interferon-gamma. These effects were abolished in the presence of the inactive precursor of Der p 1 (ProDer p 1). Taken together, these data suggest that DCs from house dust mite--sensitive patients, in contrast to DCs from healthy donors and from pollen-sensitive patients, exposed to Der p 1 play a pivotal role in the enhancement of the Th2 response associated with the allergic reaction developed in response to house dust mite exposure. (Blood. 2001;98:1135-1141)     

17beta-estradiol (E2) modulates cytokine and chemokine expression in human monocyte-derived dendritic cells

The effects of estrogen on the immune system are still largely unknown. We have investigated the effect of 17beta-estradiol (E(2)) on human monocyte-derived immature dendritic cells (iDCs). Short-term culture in E(2) had no effect on iDC survival or the expression of cell surface markers. However, E(2) treatment significantly increased the secretion of interleukin 6 (IL-6) in iDCs and also increased secretion of osteoprotegerin (OPG) by DCs. Furthermore, E(2) significantly increased secretion of the inflammatory chemokines IL-8 and monocyte chemoattractant protein 1 (MCP-1) by iDCs, but not the production of the constitutive chemokines thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC). However, after E(2) pretreatment the lipopolysaccharide (LPS)-induced production of MCP-1, TARC, and MDC by DCs was clearly enhanced. Moreover, mature DCs pretreated with E(2) stimulated T cells better than control cells. Finally, we found that E(2) provides an essential signal for migration of mature DCs toward CCL19/macrophage inflammatory protein 3beta (MIP3beta). In summary, E(2) may affect DC regulation of T-cell and B-cell responses, as well as help to sustain inflammatory responses. This may explain, in part, the reason serum levels of estrogen correlate with the severity of certain autoimmune diseases.     

哮喘患者树突状细胞分泌细胞因子的变化及其对Th1/Th2细胞因子的影响

目的观察过敏性哮喘(哮喘)患者外周血单个核细胞(PBMC)来源树突状细胞(DC)分泌IL-12和IL-10的情况,及其对Th1/Th2型细胞因子平衡的影响.方法分别取9例哮喘患者和14例正常人外周血PBMC来源的DC经LPS刺激使其发育为成熟DC(mDC).另取脐血初始T淋巴细胞(Th0).Th0和两组mDC共培养,通过ELISA法检测mDC分泌的IL-12和IL-10及辅助性T淋巴细胞(Th)分泌的IFN-γ和IL-4的含量.结果①哮喘组DC产生IL-12及其亚单位IL-12p40和IL-10较对照组显著降低(P＜0.01、P＜0.05).②哮喘组Th释放Th1型细胞因子IFN-γ较对照组减少(P＜0.05);Th2型细胞因子IL-4较对照组显著增多(P＜0.01).③两组IL-12和IFN-γ均呈正相关(r＝0.7581、P＜0.01,r＝0.6028、P＜0.05),IL-12和IL-4均呈负相关(r＝-0.7498、P＜0.01,r＝-0.7481、P＜0.01).④哮喘组IL-10与IFN-γ呈正相关(r＝0.6437,P＜0.05).⑤两组IL-12和IL-10均呈正相关(P均＜0.01).结论哮喘患者DC分泌IL-12和IL-10减少,导致Th0向Th2优势分化,细胞因子平衡向Th2型倾斜,合成IL-4增多和IFN-γ减少,后者是哮喘发生的重要机制之一.     

Increased serum IgE in alcoholics: relationship with Th1/Th2 cytokine production by stimulated blood mononuclear cells

BACKGROUND: Increased serum immunoglobulin (Ig) E values are frequently found in alcoholics. Cytokines produced by T-helper-2 (Th2) lymphocytes are required for IgE synthesis. Chronic alcoholism is associated with altered cytokine balance. This study analyzed the relationship between Th1 and Th2 cytokine production by stimulated peripheral blood mononuclear cells (PBMCs) and serum IgE levels, both in atopic and nonatopic alcoholics. METHODS: Twenty-five patients admitted to the hospital with alcohol withdrawal syndrome were included in the study. Five were classified as atopic and 20 as nonatopic by means of skin-prick tests. Interleukin-4 (IL-4), IL-10, IL-12, IL-13, and interferon gamma were measured in the supernatants of 48-hr cultures of PBMCs stimulated with phytohemagglutinin. Total serum IgE was measured by chemiluminescent enzyme immunoassay. Results were compared with those of 15 healthy controls (seven atopics and eight nonatopics). RESULTS: Total serum IgE concentrations were higher in alcoholics than in controls, in both atopic and nonatopic subjects. The ratio of IL-4 to interferon gamma production by phytohemagglutinin-stimulated PBMCs (as an approach to Th2/Th1 balance) was significantly lower in alcoholics than in healthy controls, both in the atopic and in the nonatopic group. No difference was observed regarding IL-10, IL-12, and IL-13 production between alcoholics and controls. No correlation was demonstrated between cytokine production and total serum IgE levels in any group. CONCLUSIONS: Increased total serum IgE is observed in alcoholics together with a paradoxically low ratio of Th2 to Th1 cytokine production by phytohemagglutinin-stimulated PBMCs. These findings are independent of the atopic status of patients.     

Accumulation of DC-SIGN+CD40+ dendritic cells with reduced CD80 and CD86 expression in lymphoid tissue during acute HIV-1 infection

BACKGROUND: Dendritic cells (DC) are target cells for HIV-1 and play a key role in antigen presentation and activation of T cells. OBJECTIVE: To characterize interdigitating DC in lymphoid tissue (LT) with regard to maturation, expression of cytokines and co-stimulatory molecules in HIV-1-positive patients. METHODS: DC were characterized by immunohistochemistry and in situ imaging in LT from patients with acute HIV-1 infection (aHI), antiretroviral treated patients, long-term non-progressors/slow progressors with HIV-1 infection (LTNP/SLP), patients with AIDS, HIV-1-negative controls and patients with acute Epstein-Barr virus (EBV) infection. RESULTS: A significant increase of interdigitating DC expressing CD1a, S-100b, CD83 and DC-SIGN was found in LT from patients with aHI (P < 0.02). The co-stimulatory molecules CD80 and CD86 were, however, only partially upregulated and the complete parafollicular network found in acute EBV infection was not generated, despite increased expression of interleukins 1alpha, 1beta, 12; interleukin 1alpha receptor antagonist; interferon alpha; and CD40 expression. LTNP/SLP and treated aviremic subjects had increased frequency of interdigitating DC, albeit lower than in aHI, and low expression of CD80 and CD86. In contrast, patients with AIDS had fewer DC and reduced cytokine expression in LT. CONCLUSIONS: In the early phase of HIV-1 infection, there was a migration of DC to LT comparable to that found in acute EBV infection. The infiltration of DC in LT in acute EBV infection was accompanied by upregulation of CD80 and CD86 expression, which did not occur in aHI. This co-stimulatory defect in aHI may have an impact on the development of HIV-1-specific T cell immunity.     

Calcium signaling inhibits interleukin-12 production and activates CD83(+) dendritic cells that induce Th2 cell development

Mature dendritic cells (DCs), in addition to providing costimulation, can define the Th1, in contrast to the Th2, nature of a T-cell response through the production of cytokines and chemokines. Because calcium signaling alone causes rapid DC maturation of both normal and transformed myeloid cells, it was evaluated whether calcium-mobilized DCs polarize T cells toward a Th1 or a Th2 phenotype. After human monocytes were cultured for 24 hours in serum-free medium and granulocyte-macrophage colony-stimulating factor to produce immature DCs, additional overnight culture with either calcium ionophore (CI) or interferon gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and soluble CD40L resulted in phenotypically mature DCs that produced interleukin-8 (IL-8) and displayed marked expression of CD80, CD86, CD40, CD54, CD83, DC-LAMP, and RelB. DCs matured by IFN-gamma, TNF-alpha, and soluble CD40L were additionally distinguished by undetectable CD4 expression, marked secretion of IL-12, IL-6, and MIP-1beta, and preferential ability to promote Th1/Tc1 characteristics during T-cell sensitization. In contrast, DCs matured by CI treatment were distinguished by CD4 expression, modest or absent levels of IL-12, IL-6, and MIP-1beta, and preferential ability to promote Th2/Tc2 characteristics. Calcium signaling selectively antagonized IL-12 production by mature DCs activated with IFN-gamma, TNF-alpha, and soluble CD40L. Although the activation of DCs by calcium signals is largely mediated through calcineurin phosphatase, the inhibition of IL-12 production by calcium signaling was independent of this enzyme. Naturally occurring calcium fluxes in immature DCs, therefore, negatively regulate Dc1 differentiation while promoting Dc2 characteristics and Th2/Tc2 polarization. Calcium-mobilized DCs may have clinical usefulness in treating disease states with excessive Th1/Tc1 activity, such as graft-versus-host disease or autoimmunity.     

Expression of Tyk2 in dendritic cells is required for IL-12, IL-23, and IFN-gamma production and the induction of Th1 cell differentiation

It is well documented that dendritic cells (DCs), representative antigen-presenting cells, are important sources of Th1-promoting cytokines and are actively involved in the regulation of T-helper-cell differentiation. However, the intracellular event that regulates this process is still largely unknown. In this study, we examined the role of Tyk2, a JAK kinase that is involved in the signaling pathway under IL-12 and IL-23, in DC functions. While the differentiation and maturation of DCs was normal in Tyk2-deficient (Tyk2(-/-)) mice, IL-12-induced Stat4 phosphorylation was diminished in Tyk2(-/-) DCs. IL-12-induced IFN-gamma production was also significantly diminished in Tyk2(-/-) DCs to levels similar to those in Stat4(-/-) DCs. Interestingly, Tyk2(-/-) DCs were defective in IL-12 and IL-23 production upon stimulation with CpG ODN. Furthermore, Tyk2(-/-) DCs were impaired in their ability to induce Th1-cell differentiation but not Th2-cell differentiation. Taken together, these results indicate that the expression of Tyk2 in DCs is crucial for the production of Th1-promoting cytokines such as IL-12 and IFN-gamma from DCs and thereby for the induction of antigen-specific Th1-cell differentiation.     

Endogenous NGF regulates CGRP expression in human monocytes, and affects HLA-DR and CD86 expression and IL-10 production

Our recent results on autocrine nerve growth factor (NGF) synthesis in B lymphocytes, which directly regulates the expression and release of calcitonin gene-related peptide (CGRP), a neuropeptide known to down-regulate immune response, led us to propose an anti-inflammatory action of NGF. In the present work, we investigated whether the endogenous synthesis of NGF can regulate the expression of CGRP in other antigen-presenting cells, such as monocytes, and whether this may have a functional effect. Our data indicate that human monocytes synthesize basal levels of NGF and CGRP and that, following lipopolysaccharide (LPS) stimulation, NGF and CGRP expression are both up-regulated. When endogenous NGF is neutralized, the up-regulation of CGRP expression induced by LPS is inhibited. The expression of membrane molecules involved in T-cell activation such as human leukocyte antigen-DR (HLA-DR) and CD86 is affected by endogenous NGF, and similar effects were obtained using a CGRP(1) receptor antagonist. In addition, NGF deprivation in LPS-treated monocytes significantly decreases interleukin 10 (IL-10) synthesis. Our findings indicate that endogenous NGF synthesis has a functional role and may represent a physiologic mechanism to down-regulate major histocompatibility complex (MHC) class II and CD86 expression and alter the development of immune responses.     

白细胞介素12调节小鼠Th1/Th2的抗结核分支杆菌感染研究

目的 观察、评价白细胞介素１２（ＩＬ－１２）对结核分支杆菌感染小鼠细胞因子的影响和疗效。方法 将ＢＡＬＢ／ｃ小鼠４２只,制成小鼠结核分支杆菌感染模型,随机分为对照组（ＰＢＳ）和ＩＬ－１２共两组（２１只）。给予ＰＢＳ或ＩＬ－１２治疗,检测血清γ干扰素（ＩＮＦ－γ）、ＩＬ－４、ＩＬ－１０水平（ＥＬＩＳＡ法）和器官菌数计数,观察治疗后生存率。结果 ＩＬ－１２组小鼠无一死亡、肺、肝、脾菌落数分别为（２２７     

Effects of Th1 and Th2 cytokines on cytokine production and ICAM-1 expression on synovial fibroblasts.

OBJECTIVES--To investigate the influence of the Th1 and Th2 lymphokines interleukins (IL)-4 and IL-13, interferon gamma (IFN gamma), and several monokines on the adhesion of mononuclear cells to synovial fibroblasts and intercellular adhesion molecule-1 (ICAM-1) expression and cytokine production of synovial fibroblasts in patients with osteoarthritis. METHODS--Synovial fibroblasts were isolated from patients with osteoarthritis and stimulated with IL-1 beta, IL-4, IL-6, IL-10, IL-12, IL-13, tumour necrosis factor alpha (TNF alpha), and IFN gamma. Subsequently, we determined the production of IL-1 alpha, IL-1 beta, IL-6, IL-10, IL-12, IFN alpha and TNF alpha, and the expression of ICAM-1 lymphocyte function associated antigen 3 (LFA-3), BB7, and major histocompatibility complex class II molecules on these cells. Furthermore, the adhesion of freshly isolated mononuclear cells from the peripheral blood was tested using a colourimetric cell-cell adhesion assay. RESULTS--Only production of IL-6 and the expression of ICAM-1 were observed. IL-1 beta and TNF alpha were the most potent stimulatory mediators of both cytokine production and ICAM-1 expression. IL-4 and IL-13 had differential effects as they upregulated cytokine production but downregulated IFN gamma induced ICAM-1 expression. In functional adhesion assays, TNF alpha, IL-1 alpha and, to a lesser extent, IFN gamma led to increased adhesion of mononuclear cells, whereas IL-4 and IL-13 had no effect. CONCLUSIONS--Our data indicate that Th1 and Th2 lymphokines can modulate the function (cytokine production and expression of adhesion molecules) of synovial fibroblasts.     

不同条件下尼古丁对致敏大鼠树突状细胞分泌白介素10及白介素12的影响

目的研究不同实验条件尼古丁对致敏大鼠树突状细胞（DC）及白介素10（IL-10）、白介素12（IL-12）表达的影响,从细胞水平探讨尼古丁加重哮喘的免疫学机制。方法制备致敏大鼠模型,培养骨髓来源的DC,接种于6孔培养板中,随机分为对照组及实验组,进行以下研究。①尼古丁作用的浓度依赖性研究：分别用50、100、200、400mg/L的尼古丁孵育细胞,72h后收集各组细胞的上清液;②尼古丁作用的时间依赖性研究：用400mg/L的尼古丁与细胞分别孵育0、4、8、12、24、72h,收集各组细胞的上清液。采用酶联免疫吸附双抗体夹心分析法测定各组细胞上清IL-10和IL-12的浓度。结果①DC与不同浓度尼古丁孵育72h后,200、400mg/L尼古丁组IL-10的表达较对照组均明显减少,差异有统计学意义（P〈0.01）;400mg/L尼古丁组IL-12较对照组均明显减少,差异有统计学意义（P〈0.01）;②DC与400mg/L的尼古丁分别孵育4、8、12、24、72h,其中12、24、72h组IL-10蛋白均较对照组明显减少,差异有统计学意义（P〈0.01）,12h组IL-12与对照组比较明显升高,72h组IL-12与对照组比较明显降低,差异有统计学意义（P〈0.01）。结论一定浓度的尼古丁可以抑制致敏大鼠DCIL-10及IL-12的表达,并且呈时间依赖性,这可能是吸烟加重和改变哮喘的气道炎症反应的免疫学机制之一。     

不同条件下尼古丁对致敏大鼠树突状细胞分泌白介素10及白介素12的影响

目的 研究不同实验条件尼古丁对致敏大鼠树突状细胞(DC)及白介素10(IL-10)、白介素12(IL-12)表达的影响,从细胞水平探讨尼古丁加重哮喘的免疫学机制.方法 制备致敏大鼠模型,培养骨髓来源的DC,接种于6孔培养板中,随机分为对照组及实验组,进行以下研究.①尼古丁作用的浓度依赖性研究:分别用50、100、200...