The effect of atorvastatin and its role on systemic cytokine network in treatment of acute experimental colitis

Inflammatory bowel diseases are characterized by disabilities in gastrointestinal system and defects in mucosal immune system. Statins are 3-hydroxy-3-methyl glutaryl coenzyme A reductase inhibitor and are used to treat hypercholesterolemia in patients with coronary artery and atherosclerotic diseases. Recent studies have demonstrated that statins have immunomodulatory role by effecting different pathways in immune system. In this study, we investigated the effect of atorvastatin and its mechanism on systemic immune response in treatment of trinitrobenzene sulfonic acid (TNBS)-induced colitis mice. We observed that atorvastatin significantly suppressed the severity of TNBS-induced colitis in BALB/c mice. This was manifested in reduced rectal bleeding, decrease in colon length, reduction of histological damage, and improved survival. Concurrently, we investigated the immunomodulatory role of atorvastatin on systemic immune system. We investigated the proinflammatory (IL-1α, IL-6, TNF-α), Th1 (IFN-γ, IL-2), Th2 (IL-4, IL-5, IL-10), and Th17 (IL-17, IL-23) cytokine levels in serum samples of colitis and atorvastatin-administered mice. We discovered that administration of atorvastatin significantly down-regulates systemic TNF-α level and Th17 cytokine levels. Furthermore, atorvastatin treatment switches Th1 type T-cell response toward/to Th2 (IL-4, IL-10) type response.     

Modulation of systemic antigen-specific immune responses by oral antigen in humans

Oral antigen uptake can induce systemic immune responses ranging from tolerance to immunity. However, the underlying mechanisms are poorly understood, especially in humans. Here, keyhole limpet hemocyanin (KLH), a neoantigen which has been used in earlier studies of oral tolerance, was fed in a repeated low-dose and a single high-dose protocol to healthy volunteers. KLH-specific CD4(+) T-cell proliferation and cytokine production, as well as KLH-specific serum Ab and the effects of oral KLH on a subsequent parenterally induced systemic immune response, were analyzed. Repeated low-dose oral KLH alone induced antigen-specific CD4(+) T cells positive predominantly for the gut-homing receptor integrin β7 and the cytokines IL-2 and TNF-α; some CD4(+) T cells also produced IL-4. Oral feeding of KLH accelerated a subsequent parenterally induced systemic CD4(+) T-cell response. The cytokine pattern of KLH-specific CD4(+) T cells shifted toward more IL-4- and IL-10- and less IFN-γ-, IL-2- and TNF-α-producing cells. The parenterally induced systemic KLH-specific B-cell response was accelerated and amplified by oral KLH. The impact of single high-dose oral KLH on antigen-specific immune responses was less pronounced compared with repeated low-dose oral KLH. These findings suggest that oral antigen can effectively modulate subsequently induced systemic antigen-specific immune responses. Immunomodulation by oral antigen may offer new therapeutic strategies for Th type1-mediated inflammatory diseases and for the development of vaccination strategies.     

Serum Th1 and Th2 cytokine balance in patients of superficial transitional cell carcinoma of bladder pre- and post-intravesical combination immunotherapy

Combination therapy with intravesical bacillus Calmette-Guerin (BCG) plus interferon-α2b (IFN-α2b) for superficial transitional cell carcinoma (TCC) seems to be immune-dependent and activation of Th1 immune response is required for clinical efficacy. The present study evaluates circulating serum cytokine profiles (Th1/Th2 cytokines IFN-γ, IL-2 TNF-α, IL-4, IL-6 and IL-10) in 41 bladder cancer patients prior to transurethral resection of tumor (TURBT) (pre-therapy), and following intravesical combination immunotherapy (post-therapy) and their association with recurrence. Mean levels of IL-2 and TNF-α were significantly reduced while IL-4, IL-6 and IL-10 were significantly enhanced in pre-therapy samples as compared to controls. Mean levels of IFN-γ, IL-2 and TNF-α were significantly increased while IL-4 and IL-10 were significantly reduced in patients after instillation of combination immunotherapy. These findings suggest that bladder cancer patients develop Th2 dominant status with deficient type 1 immune response that shows tendency to reversal following therapy.     

IL-33 attenuates EAE by suppressing IL-17 and IFN-γ production and inducing alternatively activated macrophages

Interleukin (IL)-33, a member of the IL-1 cytokine family, is an important modulator of the immune system associated with several immune-mediated disorders. High levels of IL-33 are expressed by the central nervous system (CNS) suggesting a potential role of IL-33 in autoimmune CNS diseases. We have investigated the expression and function of IL-33 in the development of experimental autoimmune encephalomyelitis (EAE) in mice. We report here that IL-33 and its receptor ST2 (IL-33Rα) are highly expressed in spinal cord tissue, and ST2 expression is markedly increased in the spinal cords of mice with EAE. Furthermore, ST2-deficient (ST2(-/-) ) mice developed exacerbated EAE compared with wild-type (WT) mice while WT, but not ST2(-/-) EAE mice treated with IL-33 developed significantly attenuated disease. IL-33-treated mice had reduced levels of IL-17 and IFN-γ but produced increased amounts of IL-5 and IL-13. Lymph node and splenic macrophages of IL-33-treated mice showed polarization toward an alternatively activated macrophage (M2) phenotype with significantly increased frequency of MR(+) PD-L2(+) cells. Importantly, adoptive transfer of these IL-33-treated macrophages attenuated EAE development. Our data therefore demonstrate that IL-33 plays a therapeutic role in autoimmune CNS disease by switching a predominantly pathogenic Th17/Th1 response to Th2 activity, and by polarization of anti-inflammatory M2 macrophages.     

补肾益气方对不明原因反复自然流产患者外周血Foxp3~+ Treg/Th1/Th17细胞的影响

为探讨补肾益气方对反复自然流产患者外周血Treg/Th1/Th17的影响,选取我院自然流产专科门诊30例反复自然流产(recurrent spontaneous abortion,RSA)患者,诊断为正常妊娠后开始服用补肾益气方中药,采用流式细胞仪检测服药前后Treg/Th1/Th17细胞数量,ELISA方法检测外周血TNF-α、IFN-γ、IL-4、IL-10及IL-17水平变化。结果显示中药治疗后RSA患者外周Treg细胞数量上升(5.85±2.76),明显高于服药前(3.26±1.19),P<0.05。Th1和Th17细胞数量下降(8.38±4.38和0.95±0.15),明显低于治疗前(23.59±8.14和1.58±0.71),P<0.05。IL-10和IL-4水平显著上升(P<0.05),TNF-α、IFN-γ和IL-17水平明显下降(P<0.05)。实验表明,补肾益气方中药能够调控Treg/Th1/Th17细胞水平,改变母体细胞因子分泌格局,保护胎儿不被排斥。     

小鼠皮下感染着色芽生菌病皮损中局部细胞免疫功能研究

目的 利用小鼠皮下着色芽生菌病模型,研究在不同的病程发展阶段其T细胞免疫功能的变化.方法 足垫局部皮下注射法建立小鼠的裴氏着色霉感染的着色芽生菌病模型,通过免疫组织化学技术,检测正常小鼠足垫皮肤皮损局部细胞因子IFN-γ、IL-4、IL-10、TNF-α的表达并作为对照组,观察免疫正常组和环磷酰胺免疫抑制处理的免疫抑制组小鼠分别在感染上述真菌后7 d、30 d时,皮损局部细胞因子水平变化,并与对照组比较.结果 在着色芽生菌病小鼠模型中,第7天时,免疫正常组IL-4、TNF-α和IL-10较正常对照组均出现了显著的升高(P＜0.01),表现为Th1和Th2型细胞免疫均增强的模式,并以Th2型为主;30 d时IL-10表达显著下降(P＜0.01),与同期正常对照组比较差异无统计学意义(P=0.52),IFN-γ、TNF-α水平比7 d时显著升高(P＜0.01),表现为Th2型细胞免疫减弱Th1型占主导的模式.免疫功能受损组第7天时IL-10、IL-4的水平升高与其他两组相比差异均有统计学意义(P＜0.01),IFN-γ表达水平则明显下降(P＜0.01),TNF-α的表达与正常对照组相比差异无统计学意义(P=0.39),表现为Th2型细胞免疫增强Th1功能受抑模式;30 d时,IL-10表达水平较7 d时显著减少,但仍然高于同期的免疫正常组和正常对照组,IFN-γ、TNF-α水平显著升高(P＜0.01),但却低于免疫正常组,表现为Th2型免疫模式渐弱Th1功能逐渐增强模式.结论 在不同免疫状态下小鼠着色芽生菌病感染的过程中,随着病情好转存在由Th2型细胞免疫为主导转化为Th1型细胞免疫功能占主导的过程,免疫抑制下主要表现为Th1反应受抑制,Th1型细胞因子在控制着色芽生菌病的发展过程中具有关键性的保护作用,Th2型细胞因子则可能与感染的发展进程相关.     

Th22细胞在炎症免疫性疾病中作用的研究进展

Th22细胞是最近发现的CD4+T细胞功能亚群,表达CCR6、CCR4和CCR10,且分泌IL-22和TNF-α,不分泌IFN-γ、IL-4、IL-17,是独立于Th1、Th2和Th17的细胞亚群。Th22细胞主要参与皮肤的自稳调节和病理状态,可以调控皮肤的固有免疫反应、防御功能及表皮损伤后的修复功能,在炎症性皮肤病的病理生理机制中发挥重要作用。此外,Th22细胞也参与了炎症性肠病、类风湿关节炎、肝炎、试验性自身免疫性心肌炎等炎症免疫性疾病的病理过程。本文对Th22细胞其细胞因子IL-22在炎症免疫性疾病中作用的研究进展做一综述。     

Modulation of amplitude and direction of in vivo immune responses by co-administration of cytokine gene expression cassettes with DNA immunogens

Immunization with nucleic acids has been shown to induce both antigen-specific cellular and humoral immune responses in vivo. We hypothesize that immunization with DNA could be enhanced by directing specific immune responses induced by the vaccine based on the differential correlates of protection known for a particular pathogen. Recently we and others reported that specific immune responses generated by DNA vaccine could be modulated by co-delivery of gene expression cassettes encoding for IL-12, granulocyte-macrophage colony-stimulating factor and the co-stimulatory molecule CD86. To further engineer the immune response in vivo, we investigated the induction and regulation of immune responses following the co-delivery of pro-inflammatory cytokine (IL-1α, TNF-α, and TNF-β), Th1 cytokine (IL-2, IL-12, IL-15, and IL-18), and Th2 cytokine (IL-4, IL-5 and IL-10) genes. We observed enhancement of antigen-specific humoral response with the co-delivery of Th2 cytokine genes IL-4, IL-5, and IL-10 as well as those of IL-2 and IL-18. A dramatic increase in antigen-specific T helper cell proliferation was seen with IL-2 and TNF-α gene co-injections. In addition, we observed a significant enhancement of the cytotoxic response with the co-administration of TNF-α and IL-15 genes with HIV-1 DNA immunogens. These increases in CTL response were both MHC class I restricted and CD8⁺ T cell dependent. Together with earlier reports on the utility of co-immunizing using immunologically important molecules together with DNA immunogens, we demonstrate the potential of this strategy as an important tool for the development of more rationally designed vaccines.     

The effect of Gd@C82(OH)22 nanoparticles on the release of Th1/Th2 cytokines and induction of TNF-α mediated cellular immunity

It is known that down-regulation of the immune response may be associated with the progenesis, development and prognosis of cancer or infectious diseases. Up-regulating the immune response in vivo is therefore a desirable strategy for clinical treatment. Here we report that poly-hydroxylated metallofullerenol (Gd@C₈₂(OH)₂₂) has biomedical functions useful in anticancer therapy arising from immunomodulatory effects observed both in vivo and in vitro. We found that metallofullerenol can inhibit the growth of tumors, and shows specific immunomodulatory effects on T cells and macrophages. These effects include polarizing the cytokine balance towards Th1 (T-helper cell type 1) cytokines, decreasing the production of Th2 cytokines (IL-4, IL-5 and IL-6), and increasing the production of Th1 cytokines (IL-2, IFN-γ and TNF-α) in the serum samples. Immune-system regulation by this nanomaterial showed dose-dependent behavior: at a low concentration, Gd@C₈₂(OH)₂₂ nanoparticles slightly affected the activity of immune cells in vitro, while at a high concentration, they markedly enhanced immune responses and stimulated immune cells to release more cytokines, helping eliminate abnormal cells. Gd@C₈₂(OH)₂₂ nanoparticles stimulated T cells and macrophages to release significantly greater quantities of TNF-α, which plays a key role in cellular immune processes. Gd@C₈₂(OH)₂₂ nanoparticles are more effective in inhibiting tumor growth in mice than some clinical anticancer drugs but have negligible side effects. The underlying mechanism for high anticancer activity may be attributed to the fact that this water-soluble nanomaterial effectively triggers the host immune system to scavenge tumor cells.     

Apple polyphenols require T cells to ameliorate dextran sulfate sodium-induced colitis and dampen proinflammatory cytokine expression

Human IBD, including UC and Crohn's disease, is characterized by a chronic, relapsing, and remitting condition that exhibits various features of immunological inflammation and affects at least one/1000 people in Western countries. Polyphenol extracts from a variety of plants have been shown to have immunomodulatory and anti-inflammatory effects. In this study, treatment with APP was investigated to ameliorate chemically induced colitis. Oral but not peritoneal administration of APP during colitis induction significantly protected C57BL/6 mice against disease, as evidenced by the lack of weight loss, colonic inflammation, and shortening of the colon. APP administration dampened the mRNA expression of IL-1β, TNF-α, IL-6, IL-17, IL-22, CXCL9, CXCL10, CXCL11, and IFN-γ in the colons of mice with colitis. APP-mediated protection requires T cells, as protection was abated in Rag-1(-/-) or TCRα(-/-) mice but not in IL-10(-/-), IRF-1(-/-), μMT, or TCRδ(-/-) mice. Administration of APP during colitis to TCRα(-/-) mice actually enhanced proinflammatory cytokine expression, further demonstrating a requirement for TCRαβ cells in APP-mediated protection. APP treatment also inhibited CXCR3 expression by TCRαβ cells, but not B or NK cells, in the colons of mice with colitis; however, depletion of CD4(+) or CD8(+) T cells alone did not abolish APP-mediated protection. Collectively, these results show that oral administration of APP protects against experimental colitis and diminishes proinflammatory cytokine expression via T cells.     

Roles of interleukin-17 in an experimental Legionella pneumophila pneumonia model

Interleukin-17 (IL-17) is a key factor in T helper type 17 (Th17) lineage host responses and plays critical roles in immunological control of a variety of infectious diseases. Although Legionella pneumophila, an intracellular bacterium found widely in the environment, often causes a serious and life-threatening pneumonia in humans, the contribution of IL-17 to immune function during Legionella pneumonia is unknown. In the present study, we used an experimental Legionella pneumonia infection to clarify the role of IL-17 in the resulting immune response. We observed robust production of pulmonary IL-17A and IL-17F (IL-17A/F), peaking on day 1 and declining thereafter. Upregulated production of tumor necrosis factor alpha (TNF-α), IL-6, and IL-1β, but not monocyte chemotactic protein 1 (MCP-1), was observed in Legionella-infected bone marrow-derived macrophages from BALB/c mice that had been stimulated with IL-17A or IL-17F. A significant decrease in the production of proinflammatory cytokines IL-6 and TNF-α was observed in IL-17A/F-deficient mice (BALB/c background) infected with L. pneumophila. Moreover, we found impaired neutrophil migration and lower numbers of chemokines (KC, LIX, and MIP-2) in IL-17A/F-deficient mice. IL-17A/F-deficient mice also eliminated L. pneumophila more slowly and were less likely to survive a lethal challenge. These results demonstrate that IL-17A/F plays a critical role in L. pneumophila pneumonia, probably through induction of proinflammatory cytokines and accumulation of neutrophils at the infection site.     

Interleukin-17A differentially modulates BCG induction of cytokine production in human blood macrophages

The pathogenesis of Mtb depends in part on cytokine cross-regulation between macrophages and T cells in host immunity. Th17 cells produce IL-17A to induce granuloma formation and to restrict mycobacterial dissemination. IL-17A also mediates cytokine responses induced by proinflammatory cytokines such as TNF-α. Our previous results showed that BCG induces IL-6, IL-10, and TNF-α via activity of protein kinases, including dsRNA-activated serine/threonine protein kinase and glycogen synthase kinase-3 in primary human monocytes. Therefore, we investigated whether IL-17A, upon its induction by BCG, plays an additional role to aid the production of downstream proinflammatory cytokines in macrophages. Here, we showed that IL-17A enhanced IL-6 mRNA and protein levels inducible by BCG in a time- and dose-dependent manner, whereas it had no effect on IL-10 and TNF-α production. We also demonstrated that IL-17A activated the phosphorylation of ERK1/2 triggered by BCG. With the use of a specific chemical inhibitor of a MAPK/ERK-activating kinase (MEK1/2), we confirmed the correlation between the enhanced ERK1/2 activation and augmented IL-6 production. Additionally, we revealed that IL-17A acts in concert with BCG-induced TNF-α to enhance the level of IL-6 synthesis. Taken together, our results suggest a significant role of IL-17A to serve as a modulator of cytokine expression in innate immune response during mycobacterial infection.     

Systemic administration of interferon-gamma-expressing plasmid reduces late allergic bronchitis in a mouse model of asthma

Asthma might be caused by a helper T(Th)2 immune response. We hypothesized that the systemic administration of the Th1 cytokines may reduce the Th2 type late asthmatic response (LAR). We examined the effect of the intraperitoneal injection of interferon(IFN)-gamma-expressing plasmid, a Th1 cytokine, or interleukin(IL)-4-expressing plasmid, a Th2 cytokine, at the time of sensitization on a mouse model of asthma induced by ovalbumin in BALB/c mice. We demonstrated that the IFN-gamma-expressing plasmid reduced the LAR, whereas the IL-4-expressing plasmid enhanced the LAR as compared with the saline or plasmid-only treated group. The present study suggests that the systemic administration of IFN-gamma-expressing plasmid may have a modulating ability of Th1/Th2 balance to down-regulate Th2 response by a mutual inhibitory mechanism between Th1 and Th2 cells, leading to the reduction of the LAR.