Transcriptional regulation of Th1/Th2 polarization

Listeria arpJ gene modifies T helper type 2 subset differentiation

BACKGROUND

Although the T-cell subset differentiation pathway has been characterized extensively from the view of host gene regulation, the effects of genes of the pathogen on T-cell subset differentiation during infection have yet to be elucidated. Especially, the bacterial genes that are responsible for this shift have not yet been determined.

METHODS

Utilizing a single-gene-mutation Listeria panel, we investigated genes involved in the host-pathogen interaction that are required for the initiation of T-cell subset differentiation in the early phase of pathogen infection.

RESULTS

We demonstrate that the induction of T helper types 1 and 2 (Th1 and Th2) subsets are separate phenomena and are mediated by distinct Listeria genes. We identified several candidate Listeria genes that appear to be involved in the host-Listeria interaction. Among them, arpJ is the strongest candidate gene for inhibiting Th2 subset induction. Furthermore, the analysis utilizing arpJ-deficient Listeria monocytogenes (Lm) revealed that the tumor necrosis factor (TNF) superfamily (Tnfsf) 9-TNF receptor superfamily (Tnfrsf) 9 interaction inhibits the Th2 response during Lm infection.

CONCLUSIONS

arpJ is the candidate gene for inhibiting Th2 T-cell subset induction. The arpJ gene product influences the expression of Tnfsf/Tnfrsf on antigen-presenting cells and inhibits the Th2 T-cell subset differentiation during Listeria infection.

Dendritic Cell-Based Vaccines that Utilize Myeloid Rather than Plasmacytoid Cells Offer a Superior Survival Advantage in Malignant Glioma

Dendritic cells (DCs) are professional APCs that are traditionally divided into two distinct subsets, myeloid DC (mDCs) and plasmacytoid DC (pDCs). pDCs are known for their ability to secrete large amounts of IFN-α. Apart from IFN-α production, pDCs can also process Ag and induce T cell immunity or tolerance. In several solid tumors, pDCs have been shown to play a critical role in promoting tumor immunosuppression. We investigated the role of pDCs in the process of glioma progression in the syngeneic murine model of glioma. We show that glioma-infiltrating pDCs are the major APC in glioma and are deficient in IFN-α secretion (p < 0.05). pDC depletion leads to increased survival of the mice bearing intracranial tumor by decreasing the number of regulatory T cells (Tregs) and by decreasing the suppressive capabilities of Tregs. We subsequently compared the ability of mDCs and pDCs to generate effective antiglioma immunity in a GL261-OVA mouse model of glioma. Our data suggest that mature pDCs and mDCs isolated from naive mice can be effectively activated and loaded with SIINFEKL Ag in vitro. Upon intradermal injection in the hindleg, a fraction of both types of DCs migrate to the brain and lymph nodes. Compared to mice vaccinated with pDC or control mice, mice vaccinated with mDCs generate a robust Th1 type immune response, characterized by high frequency of CD4(+)T-bet(+) T cells and CD8(+)SIINFEKEL(+) T cells. This robust antitumor T cell response results in tumor eradication and long-term survival in 60% of the animals (p < 0.001).

Transcription factor regulatory network for early lung immune response to tuberculosis in mice

Numerous transcription factors (TFs) have been suggested to have a role in Mycobacterium tuberculosis infection; however, the TFs involved in the early immune response of lung cells remains to be fully elucidated. The present study aimed to identify TFs which may have a role in the early immune response to tuberculosis and the gene regulatory networks in which they are involved. Gene expression data obtained from microarray analysis of the early lung immune response to tuberculosis (Gene Expression Omnibus; accession no. GSE23014) was integrated with data for TF binding sites and protein-protein interactions in order to construct a TF regulatory network. The role of TFs in protein complexes, active modules, topology of the network and regulation of immune processes were investigated. The results demonstrated that the constructed gene regulatory network harbored 1,270 differentially expressed (DE) genes with 4,070 regulatory and protein-protein interactions. In addition, it was revealed that 17 DE TFs were involved in the positive regulation of numerous immunological and biological processes, including T cell activation, T cell proliferation and tuberculosis-associated gene expression, in the constructed regulatory network. Signal transducer and activator of transcription 4, interferon regulatory factor 8, spleen focus-forming virus proviral integration 1, enhancer of zeste homolog 2 and kruppel-like factor 4 were predicted to be the primary TFs regulating the DE genes during early lung infection by M. tuberculosis, as determined through various analyses of the gene regulatory network. In conclusion, the present study identified novel TFs involved in the early response to M. tuberculosis infection, which may enhance current understanding of the molecular mechanism underlying tuberculosis infection and introduced potential targets for novel tuberculosis therapies.

Variants Fok1 and Bsm1 on VDR are associated with the melanoma risk: evidence from the published epidemiological studies

Background

The vitamin D receptor (VDR) mediates the major cellular activities of vitamin D and regulates various signaling pathways implicated in cancer development and progression. VDR variants have been found associated with the risk of developing melanoma; however, previous epidemiological studies are inconsistent. We have systematically reviewed the published epidemiological literature and conducted a meta-analysis to assess associations between common VDR variants and melanoma risk.

Results

We identified 10 eligible studies that evaluated six VDR variants (Apa1, Bsm1, Cdx2, EcoRV, Fok1, and Taq1) in a total of 4,961 melanoma patients and 4,605 controls. The pooled estimates identified two variants—Fok1 and Bsm1—as significantly associated with melanoma risk, but not for the other four variants Apa1, Cdx2, EcorV and Taq1. For Fok1, the pooled OR was 1.18 (95% CI = 1.06-1.30; I² = 22%) for Ff vs. FF and 1.19 (95% CI = 1.01-1.41; I² = 0%) for ff vs. FF. The dominant genetic model suggested the allele f carriers showed an 18% (pooled OR = 1.18, 95% CI = 1.07-1.29; I² = 0%) increased risk for melanoma compared to homozygote FF. In contrast, the Bsm1 was found to be associated with a decreased risk for melanoma with the pooled OR was 0.85 (95% CI = 0.76-0.95; I² = 0%) for Bb vs. bb and 0.83 (95% CI = 0.68-1.00; I² = 28%) for BB vs. bb. Under the dominant genetic model, a 15% (pooled OR = 0.85, 95% CI = 0.76-0.94; I² = 0%) decrease of melanoma risk was found for those with BB or Bb genotype compared to those of bb genotype.

Conclusions

The VDR variants Fok1 and Bsm1 may influence the susceptibility to developing melanoma, though further studies are needed to verify these conclusions.

Human Th1 dichotomy: origin, phenotype and biologic activities

The great variety of pathogens present in the environment has obliged the immune system to evolve different mechanisms for tailored and maximally protective responses. Initially, two major types of CD4+ T helper (Th) effector cells were identified, and named as type 1 (Th1) and type (Th2) cells because of the different cytokines they produce. More recently, a third type of CD4+ Th effectors has been identified and named as Th17 cells. Th17 cells, however, have been found to exhibit high plasticity because they rapidly shift into the Th1 phenotype in the inflammatory sites. Therefore, in these sites usually there is a dichotomic mixture of classic and non classic (Th17-derived) Th1 cells. In humans, non classic Th1 cells express CD161, as well as the retinoic acid orphan receptor C, IL-17 receptor E, IL-1RI, CCR6, and IL-4-induced gene 1 and Tob-1, which are all virtually absent from classic Th1 cells. The possibility to distinguish these two cell subsets may allow the opportunity to better establish their respective pathogenic role in different chronic inflammatory disorders. In this review, we discuss the different origin, the distinctive phenotypic features and the major biologic activities of classic and non classic Th1 cells. This article is protected by copyright. All rights reserved.

Suppression of vascular endothelial growth factor abrogates the immunosuppressive capability of murine gastric cancer cells and elicits antitumor immunity

The mechanisms underlying immune evasion by gastric cancer have not been well described due to a lack of gastric tumor models in immunocompetent mice. In the current study, we found that supernatants from MFC cells, a murine gastric cancer line, inhibited the lipopolysaccharide (LPS) induced maturation and cross-presentation of bone-marrow-derived dendritic cells (BMDCs). Moreover, MFC tumor-derived factors markedly altered the cytokine profiles of BMDCs, leading to a trend of increased levels of interleukin 4 (IL4), IL6, IL23 and transforming growth factor β, as well as decreased levels of tumor necrosis factor α. qPCR and ELISA revealed that MFC cells expressed a high level of vascular endothelial growth factor (VEGF). Downregulating VEGF expression abrogated the inhibitory effect of MFC-derived factors on the maturation and cross-presentation of BMDCs. In addition, VEGF knockdown greatly impaired the tumorigenicity of MFC cells in immunocompetent mice. Compared with parental MFC tumors, VEGF-low MFC tumors grew much more slowly and the survival of tumor-inoculated mice was significantly improved. More importantly, mice rejecting inoculated VEGF-low MFC tumor cells gained resistance to re-challenged parental tumors, which was attributed to an antitumor immunity response against parental MFC tumors. These results reveal an immunosuppressive role for VEGF in murine gastric cancer.

Profile of maternal CD4 T-cell effector function during normal pregnancy and in women with a history of recurrent miscarriage

The traditional paradigm suggests that during normal pregnancy maternal immunological tolerance of the allogenic fetus is association with a maternal T-lymphocyte shift from a Th1 to a Th2 phenotype, with the opposite effect reported in patients with recurrent miscarriage. However, studies on maternal peripheral blood are conflicting. In the present study, we characterized the maternal CD4 T-cell effector subsets, including the recently described Th17 subset, during normal pregnancy (cross-sectional cohort, n=71; longitudinal cohort, n=17) and contrasted this with women with recurrent miscarriage (n=24). Longitudinal analysis of peripheral blood from normal pregnancy demonstrated a fall in the percentage of Th17 cells between the first and second trimester (P≤0.05), but no significant changes were observed across gestation or the post-natal period in Th1 or Th2 subsets. In contrast, in women with a history of recurrent miscarriage, an elevated proportion of Th17 (0.314% compared with 0.097%; P=0.0009) and Th1 (12.4% compared with 5.3%; P=0.0002) cells was detected. The suggestion that Th17 cells may have a role in the normal events of implantation and early pregnancy requires further evaluation and mechanistic studies. The results of the present study, by conducting a careful longitudinal analysis, demonstrate that a peripheral Th1/Th2 shift is not a requirement for normal pregnancy. By contrast, the profound increase in Th1 and Th17 cells in women with recurrent miscarriage indicates that peripheral immunological dysfunction may be important in this group specifically, and these assays may be important in guiding therapeutic interventions in this group and warrant further investigation to determine whether they are predictive of outcome or responses to immunomodulatory therapy.

Plasticity of migrating CD1b+ and CD1b- lymph dendritic cells in the promotion of Th1, Th2 and Th17 in response to Salmonella and helminth secretions

Dendritic cells (DCs) are pivotal in the development of specific T-cell responses to control pathogens, as they govern both the initiation and the polarization of adaptive immunity. To investigate the capacities of migrating DCs to respond to pathogens, we used physiologically generated lymph DCs (L-DCs). The flexible polarization of L-DCs was analysed in response to Salmonella or helminth secretions known to induce different T cell responses. Mature conventional CD1b⁺ L-DCs showed a predisposition to promote pro-inflammatory (IL-6), pro-Th1 (IL-12p40) and anti-inflammatory (IL-10) responses which were amplified by Salmonella, and limited to only IL-6 induction by helminth secretions. The other major population of L-DCs did not express the CD1b molecule and displayed phenotypic features of immaturity compared to CD1b⁺ L-DCs. Salmonella infection reduced the constitutive expression of TNF-α and IL-4 mRNA in CD1b^- L-DCs, whereas this expression was not affected by helminth secretions. The cytokine response of T cells promoted by L-DCs was analysed in T cell subsets after co-culture with Salmonella or helminth secretion-driven CD1b⁺ or CD1b^- L-DCs. T cells preferentially expressed the IL-17 gene, and to a lesser extent the IFN-γ and IL-10 genes, in response to Salmonella-driven CD1b⁺ L-DCs, whereas a preferential IL-10, IFN-γ and IL-17 gene expression was observed in response to Salmonella-driven CD1b^- L-DCs. In contrast, a predominant IL-4 and IL-13 gene expression by CD4⁺ and CD8⁺ T cells was observed after stimulation of CD1b⁺ and CD1b^- L-DCs with helminth secretions. These results show that mature conventional CD1b⁺ L-DCs maintain a flexible capacity to respond differently to pathogens, that the predisposition of CD1b^- L-DCs to promote a Th2 response can be oriented towards other Th responses, and finally that the modulation of migrating L-DCs responses is controlled more by the pathogen encountered than the L-DC subsets.

Interferon-γ and interleukin-4 detected in serum and saliva from patients with oral lichen planus

Our previous salivary study had demonstrated an apparent T helper 2 (Th2)-predominance in saliva of oral lichen planus (OLP) patients and suggested a potential of salivary interleukin-4 (IL-4) as a biomarker for monitoring disease severity. To further determine the consistency of Th1/Th2 bias of OLP, this study investigated the expression profile of interferon-γ (IFN-γ) and IL-4 in serum and the relationship of the serum levels of these cytokines with their saliva partners. Sixty ethnic Chinese patients with OLP (40 of the erythematous/ulcerative form and 20 of the reticular form) were recruited for this study, with 40 age–sex-matched healthy volunteers as control group. IFN-γ and IL-4 levels in serum and paired saliva samples were screened by enzyme-linked immunosorbent assay. OLP patient showed a low-level IFN-γ but high-level IL-4 expression profile in both serum and saliva, with a lower IFN-γ/IL-4 ratio. Serum IL-4 level in the erythematous/ulcerative group was significantly higher than that in the reticular group. Serum levels of IFN-γ and IL-4 were significantly and positively correlated with their saliva partners. These results provided more evidence for Th2 cytokine-predominant immune imbalance in OLP, as well as the potential of IL-4 as the biomarker for monitoring severity of OLP.

JAK-STAT and intestinal mucosal immunology

The intestinal mucosal immune system is challenged with bacteria, viruses, and parasites, in addition to food and environmental antigens, that require dynamic immune responsiveness for homeostasis. One central signaling pathway is JAK-STAT, which regulates the adaptive and innate immune arms of mucosal immunity as well as epithelial repair and regeneration. Adaptive immunity includes lymphocyte mediated secretion of specific antibodies, while innate immune respones include secretion of non-antigen specific compounds. This review examines effects of specialized nutrition support on JAK-STAT in innate immune function and in lymphocyte modulation and epithelial antibody transport in gut-associated lymphoid tissue.

High-Yield Production in Escherichia coli of Fungal Immunomodulatory Protein Isolated from Flammulina velutipes and Its Bioactivity Assay in Vivo

A fungal immunomodulatory protein isolated from Flammulina velutipes (FIP-fve) has structural similarity to the variable region of the immunoglobulin heavy chain. In the present study, the recombinant bioactive FIP-fve protein with a His-tag in N-terminal of recombinant protein was expressed in transetta (DE3) at a high level under the optimized culturing conditions of 0.2 mM IPTG and 28 °C. The efficiency of the purification was improved with additional ultrasonication to the process of lysozyme lysis. The yield of the bioactive FIP-fve protein with 97.1% purity reached 29.1 mg/L with a large quantity for industrial applications. Enzyme-linked immunosorbent assay showed a maximum increase in interleukin-2 (IL-2) and gamma interferon (IFN-γ) for the mice serum group of 5 mg/kg body mass (p < 0.01) with three doses of His-FIP-fve. However, the production of IL-4 had no apparent difference compared to the control.

Aberrant histone modifications in peripheral blood mononuclear cells from patients with Henoch-Schönlein purpura

Henoch-Schönlein purpura (HSP), the most common type of leukocytoclastic vasculitis, is caused by T cell-mediated autoimmune reactions. In this study, we analyze histone modification patterns in peripheral blood mononuclear cells (PBMCs) of HSP patients, and investigate the expression levels of inflammatory cytokines (IFN-γ, IL-2, IL-4, IL-6 and IL-13), transcription factors (T-bet, GATA-3 and TIM-1) and chemokines (CXCL4 and CXCL10) in HSP patients. Our results show that histone H3 acetylation and methylation are significantly enhanced in PBMCs from HSP patients. We also demonstrate specifically that marked increases in histone H3 acetylation and H3 lysine 4 trimethylation occur at the IL-4 loci in these patients. In addition, the expression levels of IL-4, IL-6, IL-13, GATA-3, TIM-1 and CXCL4 are also increased. These findings suggest that abnormal histone modifications are present in the PBMCs of patients with HSP, possibly contributing to the activation of pathological immune responses associated with HSP.

ROCKs as immunomodulators of stroke

INTRODUCTION

Stroke is the third leading cause of death and a major cause of long-term disability in the adult population. Growing evidence suggests that inflammation may play an important role in the evolution of stroke. Because Rho-associated coiled-coil containing kinases (ROCKs) are important mediators of inflammation, they may contribute to stroke and stroke recovery.

AREAS COVERED

The pathophysiological role of ROCKs in mediating inflammation at different phases of stroke, and the therapeutic opportunities for stroke prevention and stroke treatment with ROCK inhibitors will be discussed.

EXPERT OPINION

Inflammation is a double-edged sword during the evolution of stroke. Immunomodulation might provide a novel therapeutic approach for stroke prevention and stroke treatment. ROCK plays an important role in mediating the inflammatory response following vascular injury as well as platelet activation and thrombus formation. ROCK inhibitors have been shown to be beneficial in stroke prevention, acute neuroprotection and chronic stroke recovery by affecting inflammatory-mediated platelet and endothelial function, smooth muscle contraction and neuronal regeneration. Thus, ROCK-mediated inflammation could be a potential therapeutic target for stroke prevention and stroke treatment. However, the mechanism by which ROCKs regulate the inflammatory response is unclear, and the role of the two ROCK isoforms in stroke and stroke recovery remains to be determined.

Defining the human T helper 17 cell phenotype

T helper (Th) 17 cells represent a third effector arm of CD4 T cells and complement the function of the Th1 and Th2 cell lineages. Here, we provide an overview of the transcription factors, cytokines, chemokines, and cytokine and chemokine receptors that characterize the Th17 cell phenotype. Data relevant for human Th17 cells are emphasized, with a focus on the function of two markers that have recently been associated with human Th17 cells, CD161 and interleukin-4-induced gene 1 (IL4I1). Also considered is the basis of Th17 cell plasticity towards the Th1 lineage, and we suggest that this plasticity together with the limited expansion of Th17 cells in response to T cell receptor (TCR) triggering accounts for the rarity of human Th17 cells in inflamed tissues.

In vitro rapid evolution of fungal immunomodulatory proteins by DNA family shuffling

Fungal immunomodulatory proteins (FIPs) found in a wide variety of mushrooms hold significant therapeutic potential. Despite much research, the structural determinants for their immunomodulatory functions remain unknown. In this study, a DNA shuffling technique was used to create two shuffled FIP protein libraries: an intrageneric group containing products of shuffling between FIP-glu (FIP gene isolated from Ganoderma lucidum) and FIP-gsi (FIP gene isolated from Ganoderma sinense) genes and an intergeneric group containing the products of shuffling between FIP-glu, FIP-fve (FIP gene isolated from Flammulina velutipes), and FIP-vvo (FIP gene isolated from Volvariella volvacea) genes. The gene shuffling generated 426 and 412 recombinant clones, respectively. Using colony blot analysis, we selected clones that expressed relatively high levels of shuffled gene products recognized by specific polyclonal antibodies. We analyzed the DNA sequences of the selected shuffled genes, and testing of their protein products revealed that they maintained functional abilities to agglutinate blood cells and induce cytokine production by splenocytes from Kunming mice in vitro. Meanwhile, the relationships between protein structure and the hemagglutination activity and between the changed nucleotide sites and expression levels were explored by bioinformatic analysis. These combined analyses identified the nucleotide changes involved in regulating the expression levels and hemagglutination activities of the FIPs. Therefore, we were able to generate recombinant FIPs with improved biological activities and expression levels by using DNA shuffling, a powerful tool for the generation of novel therapeutic proteins and for their structural and functional studies.

The immunological contribution of NF-κB within the tumor microenvironment: a potential protective role of zinc as an anti-tumor agent

Over decades, cancer treatment has been mainly focused on targeting cancer cells and not much attention to host tumor microenvironment. Recent advances suggest that the tumor microenvironment requires in-depth investigation for understanding the interactions between tumor cell biology and immunobiology in order to optimize therapeutic approaches. Tumor microenvironment consists of cancer cells and tumor associated reactive fibroblasts, infiltrating non-cancer cells, secreted soluble factors or molecules, and non-cellular support materials. Tumor associated host immune cells such as Th(1), Th(2), Th17, regulatory cells, dendritic cells, macrophages, and myeloid-derived suppressor cells are major components of the tumor microenvironment. Accumulating evidence suggests that these tumor associated immune cells may play important roles in cancer development and progression. However, the exact functions of these cells in the tumor microenvironment are poorly understood. In the tumor microenvironment, NF-κB plays an important role in cancer development and progression because this is a major transcription factor which regulates immune functions within the tumor microenvironment. In this review, we will focus our discussion on the immunological contribution of NF-κB in tumor associated host immune cells within the tumor microenvironment. We will also discuss the potential protective role of zinc, a well-known immune response mediator, in the regulation of these immune cells and cancer cells in the tumor microenvironment especially because zinc could be useful for conditioning the tumor microenvironment toward innovative cancer therapy.

Immunological modulation by 1α,25-dihydroxyvitamin D3 in patients with squamous cell carcinoma of the head and neck

Prior studies showing that treatment of head and neck squamous cell carcinoma (HNSCC) patients with 1α,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] stimulated intratumoral immune infiltration were extended to analysis of cytokine profiles in the periphery and in oral tissues. Most prominent was the disparity between cytokine levels in plasma and in either pathologically normal oral tissue or HNSCC tissue from patients that were untreated or treated with 1,25(OH)(2)D(3). Levels of IL-6 and IL-10, but not IL-2, IFN-γ or TNF-α, tended to be increased in the plasma of HNSCC patients and 1,25(OH)(2)D(3) further increased plasma levels of all of these cytokines. While these cytokines tended to be increased in HNSCC tissue, 1,25(OH)(2)D(3) resulted in variable cytokine responses that showed a general tendency toward further increased levels. Levels of IL-8 and VEGF were increased in plasma and tissue of untreated HNSCC patients, and were further increased in plasma, but not in tissues, of patients treated with 1,25(OH)(2)D(3). Levels of IL-1α and IL-1β were similar in plasma of controls and HNSCC patients, but were increased in HNSCC tissues. In contrast to that seen in plasma where 1,25(OH)(2)D(3) increased levels of IL-1α and IL-1β, this was not seen in tissue following 1,25(OH)(2)D(3) treatment. These results show a discordant relationship between systemic and intratumoral cytokine profiles and suggest a tendency of 1,25(OH)(2)D(3)to increase a multitude of cytokines within tumor tissue.

Alteration of helper T-cell related cytokine production in splenocytes during Trichinella spiralis infection

Infection by Trichinella spiralis takes place in two distinct phases: one is the intestinal phase and the other is the muscle phase. To evaluate alterations in cytokine production during a T. spiralis infection, we periodically assessed the cytokine production of splenocytes in mice after infection (AI). The levels of Th2-related cytokines immediately increased after the initiation of T. spiralis larval intestinal invasion (1 week AI). These early elevations in the Th2 response might be associated with the innate immune responses of intestine epithelial cells against T. spiralis larval invasion. IL-4 and IL-13 levels reached a peak prior to the initiation of nurse cell formation (2 weeks AI). Additionally, all Th17-related cytokines, except for IL-17, increased slightly until 2 weeks AI. However, expression levels for all of the Th2 and Th17-related cytokines began to decrease after the initiation of nurse cell formation and reached basal levels at 4 weeks AI, except for IL-5. At the same time, the CD4(+)CD25(+)Foxp3(+) T (regulatory T, T(reg)) cell population increased significantly in the spleen. Additionally, the number of cells in the peripheral lymph nodes increased. In conclusion, T. spiralis larva intestinal invasion induced the production of Th2 and Th17 cell-related cytokines, and the cytokines decreased with T(reg) cell-related cytokine.

Vitamin D receptor (VDR) polymorphisms and skin cancer: A systematic review

Skin cancer is the most common cancer in humans. There are several types of skin cancer that include basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and malignant melanoma (MM). The associations of vDr polymorphisms with skin cancer risk are not well characterized so far. Only a few epidemiologic studies have directly addressed the relationship between VDR polymorphisms and the incidence and prognosis of MM. To make the most of the available information on VDR polymorphisms and skin cancer (MM, BCC and SCC), we undertook a systematic review of published studies. In conclusion, data summarized in this review support the concept that the vitamin D endocrine system (VDES) is of importance for pathogenesis and progression of MM and other types of skin cancer.

Imbalance of Th1 and Th2 cells in cardiac injury induced by ambient fine particles

The study was to explore the potential immunoregulatory mechanisms linking fine particles and cardiac injury. Wistar kyoto (WKY) rats were exposed by intratracheal instillation to fine particles with the doses of 0.0, 1.6, 8.0 and 40.0mg/kg b.w., respectively. The exposure was conducted once a day, for three consecutive days. Twenty-four hours after the last exposure, the rats were sacrificed. Th1- and Th2-related transcription factors and cytokines were assessed in left ventricle of rats. The mRNA expressions of Th1- and Th2-related transcription factors signal transducer and activator of transcriptionl 1 (STAT1), signal transducer and activator of transcriptional 6 (STAT6), GATA-3 and T-bet were assessed in left ventricle of rats using real-time PCR. Meanwhile, the levels of Th1- and Th2-related cytokines IL-4, IL-13 and interferon gamma (IFN-γ) were determined by ELISA kits in cardiac homogenate supernatant of rats. Furthermore, the protein expression of IL-4 and IFN-γ were detected in myocardium by Western blot. The results of cardiac histology demonstrated exacerbated cardiac lesions and histological characterization of inflammation and degeneration in rats after exposure to fine particles. Moreover, fine particles induced significant increase of IL-4 and IL-13 and decrease of IFN-γ in myocardium of rats. The mRNA expression of STAT1, STAT6 and GATA-3 were up-regulated in left ventricle of rats in a dose-dependent manner, whereas T-bet was significantly down-regulated. The variations of these cytokines demonstrated the imbalance of Th1 and Th2 cytokines existed in cardiac injuries induced by fine particle. The imbalance of Th1/Th2 cytokines might be one of the mechanisms of immunotoxicity of cardiovascular system induced by ambient fine particles.

Characterization of Th1- and Th2-type immune response in human multidrug-resistant tuberculosis

Multidrug-resistant tuberculosis (MDR-TB) has become a lethal global threat. Insights into the immune regulation of MDR-TB are urgently needed for the development of new treatments; however, the T cell response to an MDR-TB infection in human remains unclear. In the present study, the proportion of Th1 and Th2 cell subsets and the level of related T cell subset cytokines in peripheral blood were investigated. We detected that an MDR-TB infection resulted in suppressed Th1 and Th2 cell activation, which was more remarkable in patients with MDR-TB than that in drug-sensitive tuberculosis (DS-TB) sufferers when compared to healthy controls (HCs). In addition, MDR-TB infection down-regulated the expression of IFN-γ, IL-2, and IL-10, and up-regulated IL-4, IL-6, and TNF-α expression. Our data suggest that the disturbance between protective and pathogenic effects induced by the immunosuppression of Th1- and Th2-type responses is a substantial characteristic of MDR-TB infections.

Tipifarnib-mediated suppression of T-bet-dependent signaling pathways

Large granular lymphocyte (LGL) leukemia is a chronic lymphoproliferative disease in which T-bet [T-box transcription factor 21 gene (tbx21)] overexpression may play a pathogenic role. T-bet orchestrates the differentiation of mature peripheral T-cells into interferon-γ (IFN-γ) and tumor necrosis factor-α producing CD4+ T-helper type I (Th1) and CD8+ T cytotoxic cells that are necessary for antiviral responses. When IL-12 is produced by antigen-presenting cells, T-bet expression is induced, causing direct stimulation of ifng gene transcription while simultaneously acting as a transcriptional repressor of the IL4 gene, which then leads to Th1 dominance and T-helper type 2 differentiation blockade. Additionally, T-bet has been shown to regulate histone acetylation of the ifng promoter and enhancer to loosen condensed DNA, creating greater accessibility for other transcription factor binding, which further amplifies IFNγ production. We found that treatment with a farnesyltransferase inhibitor tipifarnib reduced Th1 cytokines in LGL leukemia patient T-cells and blocked T-bet protein expression and IL-12 responsiveness in T-cells from healthy donors. The mechanism of suppression was based on modulation of histone acetylation of the ifng gene, which culminated in Th1 blockade.

The protective effect of the recombinant 53-kDa protein of Trichinella spiralis on experimental colitis in mice

BACKGROUND

Helminth infection has been proven to reduce the severity of experimental inflammatory bowel disease (IBD). The excretory-secretory proteins of helminths play an important role in the process of immunomodulation.

AIMS

In the present study, we aimed to investigate the protective potential of recombinant Trichinella spiralis (TS) 53-kDa protein (rTsP53), a component of excretory-secretory proteins, on experimental colitis in mice.

METHODS

BALB/c mice were treated subcutaneously with 50 μg rTsP53 three times at an interval of 5 days. Colitis was induced by intrarectal administration of 5 mg trinitrobenzene sulfonic acid (TNBS). Disease activities and macroscopic and microscopic scores were evaluated. To determine immune response provoked by rTsP53, we measured specific IgG1 and IgG2a values against rTsP53 in sera of mice. We also detected cytokine profiles as well as the markers of alternatively activated macrophages (M2) in mice.

RESULTS

RTsP53 ameliorated significantly the disease activity index (DAI) as well as the macroscopic and microscopic scores. IgG1 but not IgG2a was the predominant specific antibody detected in the sera of immunized mice, indicating the potential of stimulating T-helper (Th) 2 bias response by rTsP3. Pre-treatment with rTsP53 decreased serum Th1 cytokines (TNF-a, IFN-γ) and elevated serum levels of serum Th2 cytokines (IL-4, IL-13); it also decreased colonic Th1 cytokines (TNF-α, IL-6) and colonic regulatory cytokines (IL-10, TGF-β1). RTsP53 increased colonic M2 markers, arginase-1 (Arg-1), and found in inflammatory zone 1 (FIZZ1), compared to mice without rTsP53 pretreatment.

CONCLUSIONS

RTsP53 is a potential protective agent for IBD.

Role of IL-13 in systemic sclerosis

Systemic sclerosis (SSc) has the highest fatality rate among connective tissue diseases and is characterized by vascular damage, inflammation and fibrosis. Currently, no therapy has proven effective in modifying the course of SSc, a reflection of its complex pathogenesis. T cell-derived cytokines have been implicated in the induction of fibrosis. The role of the pro-fibrotic type 2 cytokine IL-13 and its regulation appear to be important in the pathogenesis of SSc and other fibrotic disorders. Recent work has shown that dysregulated production of IL-13 by effector CD8+ T cells is critical for predisposing patients to more severe forms of cutaneous disease and that this dysregulation is associated with defects in the molecular control of IL-13 production, such as increased expression of the transcription factor GATA-3. Silencing of GATA-3 with siRNA significantly reduces IL-13 production by CD8+ T cells from patients. We review these new insights into SSc pathogenesis that will enable establishment of highly relevant biomarkers of immune dysfunction in patients predisposed to develop SSc and open new possibilities for development of more specific diagnosis and treatment.

Chlamydia pneumoniae heat shock protein 60 is associated with apoptotic signaling pathway in human atheromatous plaques of coronary artery disease patients

BACKGROUND

Chlamydia pneumoniae heat shock protein (HSP) 60 is known to contribute to the activation of inflammation. In addition, there are contradictory reports on C. pneumoniae and their role in activation of pathways (apoptotic/antiapoptotic/necrosis) in coronary artery disease (CAD). Hence, more studies are required to know the actual role of C. pneumoniae in activation of apoptotic/antiapoptotic/necrosis pathways.

METHODS AND RESULTS

In this study, two sets of patient groups (cHSP60 positive and cHSP60 negative) were included and gene expression was studied by cDNA micro array and real time polymerase chain reaction arrays. Expression of Caspase-3, 8, 9, c-FLIP, PPAR-γ, PGC-1α, and Gsk-3b were also evaluated at protein level by immunoblotting. In cHSP60 positive CAD patients significantly higher (p<0.001) mRNA expression was found for CCL4, CXCL4, CXCL9, IL-8, CD40LG, CD8, TGFβ1, TGFβ2, APOE, EGR1, CTGF, APOB, LDLR, LPA, and LPL, whereas significantly lower (p<0.001) mRNA expression was detected for CD4, IL1F10, IFNA2, and IL-10 as compared to cHSP60 negative CAD patients. Additionally, at protein level expression of Caspase-3 (p=0.027), 8 (p=0.028), and 9 (p=0.037) were higher and c-FLIP (p=0.028) and PPAR-γ (p=0.95) expression were comparable in cHSP60 positive CAD patients compared to cHSP60 negative CAD patients.

CONCLUSION

Genes/proteins of pre-apoptotic caspase dependent/independent pathways, chemokines, and inflammatory cytokines receptors were significantly up-regulated in human atheromatous plaques of cHSP60 positive CAD patients suggesting an association of cHSP60 with CAD.

GATA-3 up-regulation in CD8+ T cells as a biomarker of immune dysfunction in systemic sclerosis, resulting in excessive interleukin-13 production

OBJECTIVE

Despite the importance of interleukin-13 (IL-13) in systemic sclerosis (SSc) and other fibrotic diseases, its mechanisms of action are not understood. We have reported that excessive amounts of IL-13 are produced by peripheral blood effector CD8+ T cells from patients with diffuse cutaneous SSc (dcSSc). The aim of the present study was to establish the molecular basis of IL-13 dysregulation in the pathogenesis of SSc.

METHODS

Quantitative polymerase chain reaction analysis and intracellular staining were used to study the transcription factors that control naive peripheral blood CD8+ T cell differentiation into type 1 and type 2 cytokine-secreting cells. Intracellular staining revealed that GATA-3 levels in freshly isolated naive CD8+ T cells correlated with specific clinical manifestations. We therefore assessed the effects of GATA-3 inhibition on IL-13 production in CD8+ T cells from the SSc patients.

RESULTS

Freshly isolated naive peripheral blood CD8+ T cells expressed high levels of GATA-3 and failed to down-regulate IL-13 production when cultured under type 1-skewing conditions, but maintained adequate levels of interferon-γ production. Cellular GATA-3 levels were significantly higher in patients with dcSSc and early inflammatory disease. Silencing of GATA-3 with small interfering RNA significantly reduced IL-13 production by CD8+ T cells, demonstrating a causal relationship between GATA-3 and IL-13.

CONCLUSION

These results provide important new insights into SSc pathogenesis and suggest that increased GATA-3 expression in CD8+ T cells could be a highly relevant biomarker of immune dysfunction in patients with dcSSc. GATA-3 could be a novel therapeutic target for this currently incurable disease.

Expression of a recombinant chimeric protein of hepatitis A virus VP1-Fc using a replicating vector based on Beet curly top virus in tobacco leaves and its immunogenicity in mice

We describe the expression and immunogenicity of a recombinant chimeric protein (HAV VP1-Fc) consisting of human hepatitis A virus VP1 and an Fc antibody fragment using a replicating vector based on Beet curly top virus (BCTV) in Agrobacterium-infiltrated Nicotiana benthamiana leaves. Recombinant HAV VP1-Fc was expressed with a molecular mass of approximately 68 kDa. Recombinant HAV VP1-Fc, purified using Protein A Sepharose affinity chromatography, elicited production of specific IgG antibodies in the serum after intraperitoneal immunization. Following vaccination with recombinant HAV VP1-Fc protein, expressions of IFN-γ and IL-4 were increased in splenocytes at the time of sacrifice. Recombinant VP1-Fc from infiltrated tobacco plants can be used as an effective experimental immunogen for research into vaccine development.

Vitamin D receptor (VDR) polymorphisms and skin cancer: A systematic review

Skin cancer is the most common cancer in humans. There are several types of skin cancer that include basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and malignant melanoma (MM). The associations of vDr polymorphisms with skin cancer risk are not well characterized so far. Only a few epidemiologic studies have directly addressed the relationship between VDR polymorphisms and the incidence and prognosis of MM. To make the most of the available information on VDR polymorphisms and skin cancer (MM, BCC and SCC), we undertook a systematic review of published studies. In conclusion, data summarized in this review support the concept that the vitamin D endocrine system (VDES) is of importance for pathogenesis and progression of MM and other types of skin cancer.

Recent status and prospects of the fungal immunomodulatory protein family

With the exception of polysaccharides and triterpenes/triterpenoids compounds, fungal immunomodulatory protein (FIP), a small molecule protein, is also an important bioactive component with immune regulating activity. It plays a significant role in immunomodulating. The objective of this paper was to review the latest advances in various aspects of research on FIPs, including their basic components and structural character, characters of diversity, gene cloning and expression, and their biological function, etc. In addition, prospects of utilization value and the exploitation foreground of FIPs were also discussed. The review will provide a useful reference for further research, development, and utilizations of FIPs.

Vitamin D receptor polymorphisms in patients with cutaneous melanoma

The vitamin D receptor (VDR) gene has been associated with cancer risk, but only a few polymorphisms have been studied in relation to melanoma risk and the results have been inconsistent. We examined 38 VDR gene single nucleotide polymorphisms (SNPs) in a large international multicenter population-based case-control study of melanoma. Buccal DNAs were obtained from 1,207 people with incident multiple primary melanoma and 2,469 with incident single primary melanoma. SNPs with known or suspected impact on VDR activity, haplotype tagging SNPs with ≥ 10% minor allele frequency in Caucasians, and SNPs reported as significant in other association studies were examined. Logistic regression was used to calculate the relative risks conferred by the individual SNP. Eight of 38 SNPs in the promoter, coding, and 3' gene regions were individually significantly associated with multiple primary melanoma after adjusting for covariates. The estimated increase in risk for individuals who were homozygous for the minor allele ranged from 25 to 33% for six polymorphisms: rs10875712 (odds ratios [OR] 1.28; 95% confidence interval (CI), 1.01-1.62), rs4760674 (OR 1.33; 95% CI, 1.06-1.67), rs7139166 (OR 1.26; 95%CI, 1.02-1.56), rs4516035 (OR 1.25; 95%CI, 1.01-1.55), rs11168287 (OR 1.27; 95%CI, 1.03-1.57) and rs1544410 (OR 1.30; 95%CI, 1.04-1.63); for two polymorphisms, homozygous carriers had a decreased risk: rs7305032 (OR 0.81; 95%CI 0.65-1.02) and rs7965281 (OR, 0.78; 95%CI, 0.62-0.99). We recognize the potential false positive findings because of multiple comparisons; however, the eight significant SNPs in our study outnumbered the two significant tests expected to occur by chance. The VDR may play a role in melanomagenesis.

Coriolus versicolor suppresses inflammatory bowel disease by Inhibiting the expression of STAT1 and STAT6 associated with IFN-γ and IL-4 expression

To investigate the effects of Coriolus versicolor extract (CVE) on infl ammatory bowel disease (IBD), ulcerative colitis was induced in male BALb/c mice by administering drinking water containing dextran-sulfate sodium (DSS). The mice were divided into the following four experimental groups: control, DSS-induced colitis, CVE treatment and CVE treatment + DSS-induced colitis. Mice receiving DSS treatment developed clinical and macroscopic signs of ulcerative colitis. However, treatment with CVE relieved the symptoms of IBD, including the decrease in body and organ weight. The levels of serum, spleen and mesenteric lymph node IgE in the CVE-treated groups was lower compared with the untreated groups. The antiinfl ammatory response upon CVE treatment correlated with the reduced expression of TNF-α, IL-1β and IL-6. Also, there was a significant reduction in the expression of STAT1 and STAT6 molecules, thereby leading to lower IFN-γ and IL-4 expression. Therefore, the antiinfl ammatory effects of Coriolus versicolor can be explained by its ability to inhibit certain proinflammatory cytokines.

PTB-associated splicing factor (PSF) functions as a repressor of STAT6-mediated Ig epsilon gene transcription by recruitment of HDAC1

Regulation of transcription requires cooperation between sequence-specific transcription factors and numerous coregulatory proteins. In IL-4/IL-13 signaling several coactivators for STAT6 have been identified, but the molecular mechanisms of STAT6-mediated gene transcription are still not fully understood. Here we identified by proteomic approach that the PTB-associated splicing factor (PSF) interacts with STAT6. In intact cells the interaction was observed only after IL-4 stimulation. The IL-4-induced tyrosine phosphorylation of both STAT6 and PSF is a prerequisite for the efficient association of the two proteins. Functional analysis demonstrated that ectopic expression of PSF resulted in inhibition of STAT6-mediated transcriptional activation and mRNA expression of the Igε germline heavy chain gene, whereas knockdown of PSF increased the STAT6-mediated responses. PSF recruited histone deacetylase 1 (HDAC1) to the STAT6 transcription complex, which resulted in reduction of H3 acetylation at the promoter regions of Ig heavy chain germline Igε and inhibition of STAT6-mediated transcription. In addition, the HDACs inhibitor trichostatin A (TSA) enhanced H3 acetylation, and reverted the PSF-mediated transcriptional repression of Igε gene transcription. In summary, these results identify PSF as a repressor of STAT6-mediated transcription that functions through recruitment of HDAC to the STAT6 transcription complex, and delineates a novel regulatory mechanism of IL-4 signaling that may have implications in the pathogenesis of allergic diseases and pharmacological HDAC inhibition in lymphomas.

C-MAF Oncogene Dysregulation in Multiple Myeloma: Frequency and Biological Relevance

To investigate the frequency and possible biological consequences of c-maf dysregulation, we designed c-maf and IL-4 real-time RT-PCR assays for determination of c-maf and IL-4 mRNA levels. Using the c-maf real-time RT-PCR assay, we tested a panel of 14 B-cell lines, 135 diagnostic bone marrow (BM) samples from patients with multiple myeloma and 10 BM samples from normal donors. In B cell lines and flowsorted CD38++/CD19-/CD56++ myeloma plasma cells (N = 14) the c-maf/GAPDH and IL-4/GAPDH ratios were determined simultaneously using real time RT-PCR. All B cell lines used in the study were characterized by flow cytometry and tested for the presence of Ebstein-Barr virus (EBV). B-cell lines, that were PCR negative for EBV and had a phenotype typical for primary myeloma cells, expressed medium to high levels of c-maf mRNA. However, all EBV PCR positive cell lines, showed a more immature phenotype, lacked expression of aberrant surface markers and contained very low levels of c-maf mRNA. In 4.4% (6/135) of MM patients tested, a c-maf mRNA level comparable to the cell line RPMI 8226 containing at (16:22), translocation was found. In addition, all c-maf positive myeloma cell lines and CD38++/CD19-/CD56++ myeloma plasma cells tested were IL-4 negative. In conclusion, high levels of c-maf mRNA were observed in "true MM cell lines" and 4.4% of MM patients. Further, c-maf dysregulation in myeloma plasma cells did not cause induction of IL-4 transcription.

Th17 cells: positive or negative role in tumor?

Th17 cells have been recently identified as a distinct Th cell lineage and found in an experimental animal model of cancer and in human cancers, but whether these cells promote tumor growth or regulate antitumor responses remains controversial. This review provides a summary of the current literature regarding interleukin (IL)-17/IL-23 and Th17 cells in cancer and discusses their potential roles in cancer development. Finally, we note several issues in this research area that must be resolved before the design of novel therapeutic approaches specifically targeting Th17 cells in cancer become feasible.

The cytokine milieu in the interplay of pathogenic Th1/Th17 cells and regulatory T cells in autoimmune disease

The propagation and regulation of an immune response is driven by a network of effector and regulatory T (Treg) cells. The interplay of effector T and Treg cells determines the direction of the immune response towards inflammation or its resolution in an autoimmune disease setting. In autoimmune diseases, this interplay shifts the balance in favor of the development of autoreactive effector T cells, resulting in inflammatory pathology. The objective of an effective therapeutic approach for autoimmune disease is to restore this balance. In this review, we describe the characteristics and development of pathogenic T helper 1 (Th1) and Th17 cells and the beneficial Treg cells in autoimmune diseases and the crucial roles of the cytokine milieu in influencing the balance of these T-cell subsets. Given the importance of cytokines, we discuss current immunotherapeutic strategies using cytokine or cytokine receptor antibodies for the treatment of autoimmune diseases.

Paclitaxel acts as an adjuvant to promote both Th1 and Th2 immune responses induced by ovalbumin in mice

Paclitaxel, a diterpenoid isolated from the bark of the Taxus cuspidate cv. Nana, was evaluated for its adjuvant effect on the immune responses in a mouse model. Fifty-six mice were randomly distributed into seven groups with 8 mice in each. Animals were subcutaneously immunized on days 1 and 21 with 100microg of paclitaxel, 10microg of ovalbumin (OVA), OVA with paclitaxel (50, 100 or 200microg) or with aluminum hydroxide (alum). Two weeks after the primary and boost immunizations, blood samples were collected for measurement of serum antibodies. Splenocytes were separated for detection of lymphocyte proliferation in responses to concanavalin A (Con A), lipopolysaccharide (LPS) and OVA, and mRNA expression of Th1 cytokines (IFN-gamma and IL-12), Th2 cytokines (IL-10 and IL-5) and transcription factors T-bet/GATA-3 (Th1/Th2 switcher). Results showed that coadministration of OVA with paclitaxel induced significantly higher IgG, IgG1, IgG2a, IgG2b, IgG3 and IgM responses than when OVA was used alone. In addition, up-regulated T-bet/GATA-3 together with significantly increased mRNA expression of IL-4, IL-10, IFN-gamma and IL-12 by splenocytes, as well as the proliferative responses of splenocytes to Con A, LPS and OVA were observed in paclitaxel-adjuvanted groups. Incubation of a murine macrophage-like cell line with paclitaxel significantly increased TNF-alpha and -10 released from the cells and expression of microRNAs such as miR-155, miR-147, miR-146a and miR-132. Therefore, paclitaxel activated both Th1 and Th2 responses. Considering its unique adjuvant effect demonstrated in this study and a safe record clinically used as an antineoplastic agent, paclitaxel could be an ideal adjuvant candidate when mixed Th1/Th2 immune responses are needed.