The power of combinatorial immunology: IL-12 and IL-12-related dimeric cytokines in infectious diseases

The interactions of macrophages, lymphocytes, and mesenchymal stem cells during bone regeneration

Bone regeneration and repair are crucial to ambulation and quality of life. Factors such as poor general health, serious medical comorbidities, chronic inflammation, and ageing can lead to delayed healing and nonunion of fractures, and persistent bone defects. Bioengineering strategies to heal bone often involve grafting of autologous bone marrow aspirate concentrate (BMAC) or mesenchymal stem cells (MSCs) with biocompatible scaffolds. While BMAC shows promise, variability in its efficacy exists due to discrepancies in MSC concentration and robustness, and immune cell composition. Understanding the mechanisms by which macrophages and lymphocytes - the main cellular components in BMAC - interact with MSCs could suggest novel strategies to enhance bone healing. Macrophages are polarized into pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes, and influence cell metabolism and tissue regeneration via the secretion of cytokines and other factors. T cells, especially helper T1 (Th1) and Th17, promote inflammation and osteoclastogenesis, whereas Th2 and regulatory T (Treg) cells have anti-inflammatory pro-reconstructive effects, thereby supporting osteogenesis. Crosstalk among macrophages, T cells, and MSCs affects the bone microenvironment and regulates the local immune response. Manipulating the proportion and interactions of these cells presents an opportunity to alter the local regenerative capacity of bone, which potentially could enhance clinical outcomes.

Differentiation and regulation of CD4+ T cell subsets in Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disease, and its hallmark pathological features are the loss of dopaminergic (DA) neurons in the midbrain substantia nigra pars compacta (SNpc) and the accumulation of alpha-synuclein (α-syn). It has been shown that the integrity of the blood-brain barrier (BBB) is damaged in PD patients, and a large number of infiltrating T cells and inflammatory cytokines have been detected in the cerebrospinal fluid (CSF) and brain parenchyma of PD patients and PD animal models, including significant change in the number and proportion of different CD4+ T cell subsets. This suggests that the neuroinflammatory response caused by CD4+ T cells is an important risk factor for the development of PD. Here, we systematically review the differentiation of CD4+ T cell subsets, and focus on describing the functions and mechanisms of different CD4+ T cell subsets and their secreted cytokines in PD. We also summarize the current immunotherapy targeting CD4+ T cells with a view to providing assistance in the diagnosis and treatment of PD.

Variability of Vaccine Responsiveness in Young Children

BACKGROUND

Variability in vaccine responsiveness among young children is poorly understood.

METHODS

Nasopharyngeal secretions were collected in the first weeks of life for measurement of cytokines/chemokines seeking a biomarker, and blood samples were collected at age 1 year to identify vaccine responsiveness status, defined as low vaccine responder (LVR), normal vaccine responder (NVR), and high vaccine responder (HVR), to test for vaccine antigen-induced immune memory and for antigen-presenting cell (APC) function.

RESULTS

Significantly lower specific cytokine/chemokine levels as biosignatures, measurable in nasopharyngeal secretions at infant age 1-3 weeks, predicted LVR status compared to NVR and HVR children. Antibiotic exposures were correlated with increased occurrence of LVR. At age 1 year, LVRs had fewer CD4+ T-helper 1 and T-helper 2 memory cells responsive to specific vaccine antigens. APC responses observed among LVRs, both at rest and in response to Toll-like receptor 7/8 stimulation by R848, were suboptimal, suggesting that altered innate immunity may contribute to immune deficiency in LVRs.

CONCLUSIONS

Cytokine biosignatures in the first weeks of life may predict vaccine responsiveness in children during the first year of life. Antibiotic exposure is associated with LVR in children. CD4+ T-cell memory induction and APC deficiencies occur in LVR children.

Preeclampsia at term: evidence of disease heterogeneity based on the profile of circulating cytokines and angiogenic factors

BACKGROUND

Intravascular inflammation and an antiangiogenic state have been implicated in the pathophysiology of preeclampsia. On the basis of the profiles of their angiogenic/antiangiogenic factors, women with preeclampsia at term may be classified into 2 subgroups with different characteristics and prevalence of adverse outcomes. This study was undertaken to examine whether these 2 subgroups of preeclampsia at term also show differences in their profiles of intravascular inflammation.

OBJECTIVE

This study aimed to determine the plasma profiles of cytokines and chemokines in women with preeclampsia at term who had a normal or an abnormal angiogenic profile.

STUDY DESIGN

A nested case-control study was conducted to include women classified into 3 groups: women with an uncomplicated pregnancy (n=213) and women with preeclampsia at term with a normal (n=55) or an abnormal (n=41) angiogenic profile. An abnormal angiogenic profile was defined as a plasma ratio of placental growth factor and soluble fms-like tyrosine kinase-1 multiple of the median <10th percentile for gestational age. Concentrations of cytokines were measured by multiplex immunoassays.

RESULTS

Women with preeclampsia at term and an abnormal angiogenic profile showed evidence of the greatest intravascular inflammation among the study groups. These women had higher plasma concentrations of 5 cytokines (interleukin-6, interleukin-8, interleukin-12/interleukin-23p40, interleukin-15, and interleukin-16) and 7 chemokines (eotaxin, eotaxin-3, interferon-γ inducible protein-10, monocyte chemotactic protein-4, macrophage inflammatory protein-1β, macrophage-derived chemokine, and thymus and activation-regulated chemokine compared to women with an uncomplicated pregnancy. By contrast, women with preeclampsia at term and a normal angiogenic profile, compared to women with an uncomplicated pregnancy, had only a higher plasma concentration of monocyte chemotactic protein-4. A correlation between severity of the antiangiogenic state, blood pressure, and plasma concentrations of a subset of cytokines was observed.

CONCLUSION

Term preeclampsia can be classified into 2 clusters. One is characterized by an antiangiogenic state coupled with an excessive inflammatory process, whereas the other has neither of these features. These findings further support the heterogeneity of preeclampsia at term and may explain the distinct clinical outcomes.

The role of sialic acid-binding immunoglobulin-like-lectin-1 (siglec-1) in immunology and infectious disease

Siglec-1, also known as Sialoadhesin (Sn) and CD169 is highly conserved among vertebrates and with 17 immunoglobulin-like domains is Siglec-1 the largest member of the Siglec family. Expression of Siglec-1 is found primarily on dendritic cells (DCs), macrophages and interferon induced monocyte. The structure of Siglec-1 is unique among siglecs and its function as a receptor is also different compared to other receptors in this class as it contains the most extracellular domains out of all the siglecs. However, the ability of Siglec-1 to internalize antigens and to pass them on to lymphocytes by allowing dendritic cells and macrophages to act as antigen presenting cells, is the main reason that has granted Siglec-1's key role in multiple human disease states including atherosclerosis, coronary artery disease, autoimmune diseases, cell-cell signaling, immunology, and more importantly bacterial and viral infections. Enveloped viruses for example have been shown to manipulate Siglec-1 to increase their virulence by binding to sialic acids present on the virus glycoproteins allowing them to spread or evade immune response. Siglec-1 mediates dissemination of HIV-1 in activated tissues enhancing viral spread via infection of DC/T-cell synapses. Overall, the ability of Siglec-1 to bind a variety of target cells within the immune system such as erythrocytes, B-cells, CD8+ granulocytes and NK cells, highlights that Siglec-1 is a unique player in these essential processes.

The emerging role of Th1 cells in atherosclerosis and its implications for therapy

Atherosclerosis is a chronic progressive inflammatory disease of the large and medium-sized artery walls. The molecular mechanisms regulating the onset and progression of atherosclerosis remain unclear. T cells, one of the most common immune cell types in atherosclerotic plaques, are increasingly recognized as a key mediator in the pathogenesis of atherosclerosis. Th1 cells are a subset of CD4⁺ T helper cells of the adaptive immune system, characterized by the expression of the transcription factor T-bet and secretion of cytokines such as IFN-γ. Converging evidence shows that Th1 cells play a key role in the onset and progression of atherosclerosis. Besides, Th1 is the central mediator to orchestrate the adaptive immune system. In this review, we aim to summarize the complex role of Th1 cells in atherosclerosis and propose novel preventative and therapeutic approaches targeting Th1 cell-associated specific cytokines and receptors to prevent atherogenesis.

Effect of 1,3-Beta Glucans Dietary Addition on the Growth, Intestinal Histology, Blood Biochemical Parameters, Immune Response, and Immune Expression of CD3 and CD20 in Broiler Chickens

This experiment evaluated the impact of the dietary addition of 1,3-β-glucans (GLU) on broiler chickens’ growth, intestinal histology, blood biochemical parameters, and immunity. Two hundred three-day-old male broilers (Ross 308) (97.93 ± 0.19 g/chick) were randomly assigned into four treatments with five replicates, each containing ten birds, in a complete randomized design. The four treatments were formulated with 0, 50, 100, and 150 mg 1,3-β-glucans kg−1 in broiler chicken diets. During the study, no significant impacts (p > 0.05) were observed in weight gain and feed conversion ratio (FCR) between treatment groups. Based on the results of total body weight gain and FCR, the optimal level of 1,3-β-glucan is 120 mg Kg−1. The intestinal histomorphology was improved by GLU supplementation, as indicated by increased villi height and villi height to crypt depth ratio (p < 0.01). All levels of supplemental β-1,3 glucan decreased the serum total cholesterol (TC), triglyceride levels, and low-density lipoprotein cholesterol (LDL-C) (p < 0.05). The serum levels of growth hormones (GH), triiodothyronine (T3), and thyroxine (T4) were increased in GLU-supplemented groups (p < 0.05). The serum immune indices (lysozyme activity, interleukin 10 (IL10), complement 3 (C3), and total protein levels) were increased in the GLU-supplemented groups (p < 0.05). Dietary GLU up-regulated the immunoexpression of CD3 (T-cell marker) and CD20 (B-cell marker) in the spleen of birds (p < 0.01). It can be concluded that 1,3-β-glucan can be added to broiler chicken diets for improving the development and integrity of the intestine and enhancing the bird’s immune status. The optimal level for 1,3-β-glucan dietary supplementation was 120 mg Kg−1. Dietary 1,3-β-glucan has a hypolipidemic effect and improves the hormonal profile of birds without affecting their growth rate.

Pharmacological inhibition of the mTOR pathway alters phenotype and cytokine expression in bovine monocyte-derived dendritic cells

Epidemiological studies have long demonstrated the association of nutrient status and immune dysfunction in dairy cows. Postpartum dairy cows experiencing a nutrient deficit show a propensity for increased inflammatory response, decreased pathogen clearance, and increased incidence of infectious disease. Studies in cows and other species show that the nutrient sensing mechanistic target of rapamycin (mTOR) signaling pathway could be one potential causal pathway connecting the deficit in nutrient availability and the heightened inflammatory response. Our objective was to investigate the effects of pharmacological mTOR pathway inhibition on phenotype and cytokine expression of bovine monocyte derived dendritic cells (moDC). We differentiated CD14⁺ monocytes from dairy cows (n = 14) into moDC in the presence or absence of first- or second-generation mTOR inhibitor rapamycin and PP242 (both 100 nM), respectively. On day seven cells were matured with E. coli lipopolysaccharide (LPS, 100 ng/mL) or left unstimulated to represent naïve moDC. Surface expression of CD14, CD40, CD80, and MHCII was measured via flow cytometry. We measured mRNA expression of IL10, IL12A, IL12B, and TNFα by rt-qPCR, and protein concentrations of IL-10 and TFN-α in cell culture supernatants with a bead-based multiplex assay. Cultures from ten cows successfully developed the moDC phenotype in culture without inhibitors, defined as increased surface expression of CD40, CD80, and MHCII compared with naïve moDC. Only data from these cows were considered for the results on effects of mTOR inhibitors. In naïve and mature moDC mTOR inhibition increased MHCII expression compared to controls. In mature moDC, in addition to MHCII, CD80 expression was increased compared with untreated LPS-stimulated controls. Expression of IL12A mRNA was upregulated in mature, mTOR inhibited moDC compared with untreated controls. In cell culture supernatants mTOR inhibition reduced IL-10 and increased TNF-α concentrations in naïve and mature moDCs compared with untreated controls. Overall rapamycin had a more consistent effect on altering phenotype and cytokine expression of moDC than PP242. In summary we observed an increased expression of co-stimulatory molecules and antigen presentation potential in mature moDC differentiated under mTOR inhibition, and a cytokine pattern that would potentially favor a Th1 type response. This study provides novel data indicating a role for mTOR signaling in bovine moDC phenotype and mediator profile. This proof-of-concept study demonstrates the role of the mTOR pathway in shaping the bovine immune response and may help to provide mechanistic insight and opportunities for modulation of the immune response during the nutrient deficit of early lactation.

Nasopharyngeal microbiome analyses in otitis-prone and otitis-free children

OBJECTIVES

About 10-15% children develop frequent acute otitis media (AOM) confirmed by tympanocentesis. These children are designated sOP (stringently defined otitis-prone) because all AOM episodes have been microbiologically confirmed. The cause of otitis-proneness in sOP children is multi-factorial, including frequent otopathogen nasopharyngeal (NP) colonization and deficiency in innate and adaptive immune responses. A largely unexplored contributor to otitis proneness is NP microbiome composition. Since the microbiome modulates otopathogen NP colonization and immune responses, we hypothesized that the NP microbiome composition in sOP children might be dysregulated.

METHODS

We performed 16S rRNA sequencing to analyze microbiome composition in 157 NP samples from 28 sOP and 68 AOM-free children when they were 6 months or 12 months old and healthy. Bioinformatic approaches were employed to examine the composition difference between the two populations and its correlation with changes in levels of inflammatory cytokines.

RESULTS

A different global microbiome profile and reduced alpha diversity was observed in the NP microbiome of sOP children when 6 months old, compared with that from AOM-free children of the same age. This difference was resolved when groups were compared at 12 months old. We found 4 bacterial genera-Bacillus, Veillonella, Gemella, and Prevotella-correlated with higher levels of pro-inflammatory cytokines in the NP. Those 4 bacterial genera were in lower abundance in sOP compared to AOM-free children.

CONCLUSION

Dysbiosis occurs in the NP microbiome of sOP children at an early age even when they were healthy. This dysbiosis correlates with a lower inflammatory state in the NP of these children.

Recent advances in understanding the Th1/Th2 effector choice

For over 35 years since Mosmann and Coffman proposed the seminal “type 1 T helper (Th1)/type 2 T helper (Th2)” hypothesis in 1986, the immunological community has appreciated that naïve CD4 T cells need to make important decisions upon their activation, namely to differentiate towards a Th1, Th2, Th17 (interleukin-17-producing T helper), follicular T helper (Tfh), or regulatory T cell (Treg) fate to orchestrate a variety of adaptive immune responses. The major molecular underpinnings of the Th1/Th2 effector fate choice had been initially characterized using excellent reductionist in vitro culture systems, through which the transcription factors T-bet and GATA3 were identified as the master regulators for the differentiation of Th1 and Th2 cells, respectively. However, Th1/Th2 cell differentiation and their cellular heterogeneity are usually determined by a combinatorial expression of multiple transcription factors, particularly in vivo, where dendritic cell (DC) and innate lymphoid cell (ILC) subsets can also influence T helper lineage choices. In addition, inflammatory cytokines that are capable of inducing Th17 cell differentiation are also found to be induced during typical Th1- or Th2-related immune responses, resulting in an alternative differentiation pathway, transiting from a Th17 cell phenotype towards Th1 or Th2 cells. In this review, we will discuss the recent advances in the field, focusing on some new players in the transcriptional network, contributions of DCs and ILCs, and alternative differentiation pathways towards understanding the Th1/Th2 effector choice in vivo.

The Modulating Effect of Dietary Beta-Glucan Supplementation on Expression of Immune Response Genes of Broilers during a Coccidiosis Challenge

Simple Summary

Avian coccidiosis is the leading parasitic disease in the poultry industry and means to control its damages continue to be explored. This study evaluated the feeding effects of a yeast-derived β-glucan on expression of immune response genes in the spleen, thymus, and bursa of commercial broiler chickens during an Eimeria challenge. The study consisted of two dietary treatments (0% or 0.1% β-glucan) each with or without a coccidiosis challenge. There were significant effects from dietary β-glucan, Eimeria challenge, and their interaction for several gene targets in the spleen, thymus, and bursa on days 10 and 14 of age. Based on the current results, supplementation of dietary β-glucan in Eimeria-challenged birds enhanced and modulated the expression of immune response genes during coccidiosis.

Abstract

This study investigated the effects of a yeast-derived β-glucan (Auxoferm YGT) supplementation on mRNA expression of immune response genes in the spleen, thymus, and bursa of broiler chickens during a mixed Eimeria infection. Day (d)-old chicks (n = 1440) were fed diets containing 0% or 0.1% YGT. On d 8 post-hatch, half the replicate pens (n = 8) were challenged with a mixed inoculum of E. acervulina, E. maxima, and E. tenella. On d 10 and d 14 post-hatch, the spleen, thymus, and bursa were collected to evaluate mRNA abundance by quantitative real-time PCR. Data were analyzed using PROC GLIMMIX model (2-way interaction) and differences were established by LS-MEANS with significance reported at p ≤ 0.05. In spleen tissues at d 10, expression of interleukin (IL)-10 and inducible nitric oxide synthase (iNOS) were elevated in both 0.1% YGT-fed challenged and non-challenged birds. In thymus tissues at d 14, expression of IL-10, IL-17F, interferon (IFN)-γ, iNOS, and macrophage migration inhibitory factor (MIF) were elevated in challenged birds fed 0.1% YGT. In bursal tissues at d 10 and d 14, expression of IL-10, IFN-γ, iNOS (d 10 only), and MIF were elevated in 0.1% YGT-fed challenged and non-challenged birds. Dietary β-glucan supplementation to chicken diets modulated their immune response to the Eimeria challenge.

Interleukin-35: An emerging player in the progression of liver diseases

Interleukin-35(IL-35), a newly identified immunosuppressive cytokine, has recently been shown to play a significant role in the progression of various autoimmune diseases and malignant tumors. The liver is the largest organ in the body and is generally regarded as an important lymphoid organ by an increasing number of immunologists. A number of reports have demonstrated that IL-35 plays essential roles in maintaining the immune homeostasis of the liver microenvironment. This review summarizes the existing studies of IL-35 in liver diseases, including viral hepatitis, immune liver injury, liver cirrhosis and carcinoma. We aimed to provide a comprehensive overview of the vital roles of IL-35 in hepatic damage and explore new alternative therapeutic targets for these diseases.

Is individual genetic susceptibility a link between silica exposure and development or severity of silicosis? A systematic review

BACKGROUND

Silicosis is a lung disease of fibrotic nature resulting from the inhalation and deposition of dust containing crystalline silica. Subjects exposed to the same environmental factors may show distinct radiological manifestations, and since silicosis is known as a multifactorial disease, it is plausible that individual genetic susceptibility may play a role in the pathology. This review of the literature aims to provide an assessment of the present data on the genetic association studies in silicosis and describe the genes that potentially might influence silicosis susceptibility in silica-exposed individuals.

METHODS

We accessed the database of PubMed for articles published in English about interindividual genetic susceptibility to silicosis using terms related to the subject matter.

RESULTS

Following the evaluation process, 28 studies were included in this systematic review, including 23 original studies and 5 meta-analyses.

CONCLUSIONS

Regardless of the advances in the knowledge of the importance of gene variations in silicosis, more studies need to be performed, in particular, special polygenic and genome-wide investigations.

Peroxisome Proliferator-Activated Receptor-δ Acts within Peripheral Myeloid Cells to Limit Th Cell Priming during Experimental Autoimmune Encephalomyelitis

Peroxisome proliferator-activated receptor (PPAR)-δ is a fatty acid-activated transcription factor that regulates metabolic homeostasis, cell growth, and differentiation. Previously, we reported that mice with a global deficiency of PPAR-δ develop an exacerbated course of experimental autoimmune encephalomyelitis (EAE), highlighting a role for this nuclear receptor in limiting the development of CNS inflammation. However, the cell-specific contribution of PPAR-δ to the more severe CNS inflammatory response remained unclear. In this study, we studied the specific involvement of PPAR-δ in myeloid cells during EAE using mice that had Cre-mediated excision of floxed Ppard driven by the lysozyme M (LysM) promoter (LysM ^Cre :Ppard ^fl/fl). We observed that LysM ^Cre :Ppard ^fl/fl mice were more susceptible to EAE and developed a more severe course of this disease compared with Ppard ^fl/fl controls. The more severe EAE in LysM ^Cre :Ppard ^fl/fl mice was associated with an increased accumulation of pathogenic CD4⁺ T cells in the CNS and enhanced myelin-specific Th1 and Th17 responses in the periphery. Adoptive transfer EAE studies linked this EAE phenotype in LysM ^Cre :Ppard ^fl/fl mice to heightened Th responses. Furthermore, studies using an in vitro CD11b⁺ cell:Th cell coculture system revealed that CD11b⁺CD11c⁺ dendritic cells (DC) from LysM ^Cre :Ppard ^fl/fl mice had a heightened capacity to prime myelin oligodendrocyte glycoprotein (MOG)-specific Th cells compared with Ppard ^fl/fl counterparts; the effects of DC on Th1 cytokine production were mediated through production of the IL-12p40 homodimer. These studies revealed a role for PPAR-δ in DC in limiting Th cell priming during EAE.

Interleukin 27 is up-regulated in patients with active inflammatory bowel disease

The aim of the study was to characterize and quantify tissue gene and protein expression of IL-27 in ulcerative colitis (UC) and Crohn's disease (CD) patients. This is an observational and cross-sectional study. Fifty-four patients with IBD were studied: 27 active UC, 12 inactive UC, 10 active CD, and 5 inactive CD. All patients belonged to the Inflammatory Bowel Disease Clinic at the Instituto Nacional de Ciencias Médicas y Nutrición. We found that IL-27 gene expression was significantly higher in active UC versus inactive UC group (P = 0.015). The IL-27 mRNA expression was increased in patients with active CD compared with inactive CD disease (P = 0.035). The percentage of IL-27 immunoreactive cells was higher in active UC versus active CD patients and non-inflamed tissue controls. The IL-27 was significantly elevated in active UC and CD patients, and it was associated with disease severity.

Identification of a single p19 gene and three p40 paralogues in grass carp (Ctenopharyngodon idellus): Their potential for the formation of interleukin 23 and inducible expression in vitro and in vivo

Interleukin (IL-) 23, a member of IL-12 family, is a composite cytokine with the subunits of p19 and p40. Although IL-12 and IL-23 share the p40 subunit, they play vastly different roles in immune regulation. In teleost, much emphasis has been placed on the identification of IL-12, but evidence for the existence of IL-23 is still lacking. In the present study, a p19 gene and three p40 paralogues were isolated and identified from grass carp, suggesting multiple assembly of IL-23 molecules in fish species. To address this issue, the existence of different p19/p40 heterodimers were examined by Co-Immunoprecipitation (Co-IP) assay, showing that only co-expression of p19 and each p40 subunit could produce the soluble proteins corresponding to three IL-23 isoforms. Additionally, bacterial infection could up-regulate the mRNA expression of p19, p40a and p40b but not p40c in head kidney, indicating distinct expression patterns of three p40 paralogues. Moreover, in vitro experiments demonstrated that both B-cell stimulator, LPS and T-cell mitogen, PHA markedly increased the mRNA levels of p19 and three p40 paralogues in grass carp periphery blood lymphocytes (PBLs). The simultaneous up-regulation of mRNA expression of p19 and p40 paralogues in response to immune stimuli supports the idea that p19 may form heterodimeric molecules with three p40 subunits in grass carp under immune activation. These findings for the first time highlight the potential of p19 and p40 for dimerization in fish, particularly the existence of three IL-23 isoforms as soluble heterodimeric cytokines in grass carp, thereby providing the basis for further investigating the function of IL-23 in fish immunity.

Functional variant in the promoter region of IL-27 alters gene transcription and confers a risk for ulcerative colitis in northern Chinese Han

Ulcerative colitis (UC) is a chronic inflammatory disorder of unknown etiology and a polygenic disease. IL-27 encodes p28, a subunit of IL-12 family cytokines, and has been implicated in the pathogenesis of UC. The aims of the present study were to evaluate the genetic association of a variant of the IL-27 gene with UC and to further characterize the functional variant in the IL-27 gene that influences the risk for UC. Our data demonstrated that the genetic variant rs153109 in the 5' upstream region of IL-27 is significantly associated with UC in Chinese Han individuals. Analysis of IL-27 transcripts demonstrated that individuals carrying the risk allele of rs153109 display reduced transcription of IL-27 in PBMCs. Luciferase activity assays demonstrated that the risk allele rs153109 results in decreased promoter activity compared to a non-risk allele in a tissue specific manner. Mechanistic characterization of histone modifications in the promoter region revealed that the risk haplotype tagged by the risk allele of rs153109 reduces the levels of H3K3me3 and H3K27ac.

IL-12B and IL-10 gene polymorphisms in the development of Hashimoto's thyroiditis

Functional genetic polymorphisms that altered gene expression of cytokines are candidate genetic factors that could modulate the development and progression of Hashimoto's thyroiditis (HT). IL-12B gene encoded the IL-12p40 subunit, which is included in the pro-inflammatory heterodimeric cytokines IL-12p70 and IL-23. IL-10 is an important Treg cytokine suppressing inflammatory cytokine production and autoimmunity. This study was designed to compare -1082A/GIL-10 and +1188A/C3'UTRIL-12B genotype distribution in 130 patients with HT to a group of 157 healthy controls in attempts to determine an association with HT development. Genotyping for the 3'UTRA/C IL-12B polymorphism was performed using RFLP-PCR and genotyping for -1082A/G IL-10 by ARMS-PCR assay. Patients with HT were divided into euthyroid and hypothyroid stages. There were no significant differences in the genotype and allele frequencies of the IL-12B polymorphism between patients with HT and controls. We observed higher euthyroid HT risk for individuals with CC genotype, unlike to develop hypothyroidism with OR = 1.68. Regarding the polymorphism rs1800896, it was shown the significantly higher frequency of homozygous genotype GG in cases vs controls (OR = 2.19; P = 0.024). Moreover, the combination of genotype AA of 3'UTRIL-12B with GG of -1082IL-10 was associated with a threefold increasing risk (OR = 3.188; P = 0.022) of developing HT compared to individuals with the presence of 3'UTR allele C (AC+CC) simultaneously with AA genotype of -1082IL-10. Our data raise the possibility that the combined effect of polymorphisms from proinflammatory and anti-inflammatory cytokines may be more decisive to HT development.

Protective role of Interleukin 27 (IL-27) gene polymorphisms in patients with ulcerative colitis

Ulcerative colitis (UC) is a chronic condition of unknown etiology and a polygenic disease. The interleukin 27 (IL-27) have been implicated in the pathogenesis of several autoimmune diseases including inflammatory bowel disease. Several polymorphisms of IL-27 have been associated with several types of cancer and immune disorders. The aim of the present study was to evaluate the association between IL-27 gene polymorphisms and the development of UC. Four polymorphisms of IL-27p28 gene (rs181206, rs26528, rs17855750, and rs40837) and three of the Epstein-Barr virus-induced gene 3 (EBI3) (rs428253, rs4740, and rs4905) were genotyped by 5' exonuclease TaqMan genotyping assays on an ABI Prism 7900HT Fast Real-Time PCR System in 375 Mexican patients with UC and 1599 Mexican Mestizo healthy unrelated individuals. IL-27 levels were determined in 458 healthy controls. Under recessive model adjusted by age and gender, the IL-27p28 rs17855750 polymorphism was associated with decreased risk of developing UC (OR=0.27, 95% CI: 0.06-1.13, P=0.031). On the other hand, under recessive models adjusted by age and gender, the EBI3 rs428253 (OR=0.54, 95% CI: 0.29-0.99, P=0.035), rs4740 (OR=0.60, 95% CI: 0.36-1.01, P=0.046) and rs4905 (OR=0.59, 95% CI: 0.35-1.01, P=0.043) were associated with decreased risk of developing UC. Similar levels of IL-27 were observed among the genotypes of the studied polymorphisms. IL-27 polymorphisms might play a protective role for the development of UC in the Mexican population.

A soluble form of the interleukin-6 family signal transducer gp130 is dimerized via a C-terminal disulfide bridge resulting from alternative mRNA splicing

Interleukin-6 (IL-6) signaling can be divided into classic signaling (via the membrane-bound IL-6 receptor, IL-6R) and trans-signaling (via the soluble IL-6R, sIL-6R), and both modes of signaling activate cells via a homodimer of the ubiquitously expressed β-receptor glycoprotein 130 (gp130). IL-6 trans-signaling is responsible for most of the pro-inflammatory activities of IL-6 and plays a role in many inflammatory diseases including inflammation-driven cancers. IL-6 trans-signaling can be selectively inhibited by soluble forms of gp130. To date, three forms of sgp130 (full-length sgp130, sgp130-RAPS and sgp130-E10) with different molecular weight have been described, which originate from alternative splicing or alternative polyadenylation of the gp130 mRNA. All these proteins are capable of blocking signaling of the IL-6/sIL-6R complex, albeit with different efficacy. The full length form of sgp130 comprises the domains D1 to D6 and a short unique C-terminus which arises from alternative splicing. In the present study, we analyze the role of a unique cysteine residue (Cys-628) within this C-terminus, which is contained neither in the membrane-bound gp130 nor in the two other sgp130 forms. Full-length sgp130 can form a disulfide-linked dimer via this cysteine residue. These natural sgp130 dimers are absent under reducing conditions or in a sgp130 C628A mutant. Although the disulfide-dimerized sgp130 represents only a small fraction of the total amount of sgp130 and, thus, may appear to be dispensable for the global inhibitory activities of sgp130 in the circulation, it may represent a further possibility to modulate gradients of sgp130 with different properties depending on the local redox potential in a cell- or tissue-dependent manner.

Intracellular Networks of the PI3K/AKT and MAPK Pathways for Regulating Toxoplasma gondii-Induced IL-23 and IL-12 Production in Human THP-1 Cells

Interleukin (IL)-23 and IL-12 are closely related in structure, and these cytokines regulate both innate and adaptive immunity. However, the precise signaling networks that regulate the production of each in Toxoplasma gondii-infected THP-1 monocytic cells, particularly the PI3K/AKT and MAPK signaling pathways, remain unknown. In the present study, T. gondii infection upregulated the expression of IL-23 and IL-12 in THP-1 cells, and both cytokines increased with parasite dose. IL-23 secretion was strongly inhibited by TLR2 monoclonal antibody (mAb) treatment in a dose-dependent manner and by TLR2 siRNA transfection, whereas IL-12 secretion was strongly inhibited by TLR4 mAb treatment dose-dependently and by TLR4 siRNA transfection. IL-23 production was dose-dependently inhibited by the PI3K inhibitors LY294002 and wortmannin, whereas IL-12 production increased dose-dependently. THP-1 cells exposed to live T. gondii tachyzoites underwent rapid p38 MAPK, ERK1/2 and JNK activation. IL-23 production was significantly upregulated by the p38 MAPK inhibitor SB203580 dose-dependently, whereas pretreatment with 10 μM SB203580 significantly downregulated IL-12 production. ERK1/2 inhibition by PD98059 was significantly downregulated IL-23 production but upregulated IL-12 production. JNK inhibition by SP600125 upregulated IL-23 production, but IL-12 production was significantly downregulated dose-dependently. T. gondii infection resulted in AKT activation, and AKT phosphorylation was inhibited dose-dependently after pretreatment with PI3K inhibitors. In T. gondii-infected THP-1 cells, ERK1/2 activation was regulated by PI3K; however, the phosphorylation of p38 MAPK and JNK was negatively modulated by the PI3K signaling pathway. Collectively, these results indicate that IL-23 production in T. gondii-infected THP-1 cells was regulated mainly by TLR2 and then by PI3K and ERK1/2; however, IL-12 production was mainly regulated by TLR4 and then by p38 MAPK and JNK. Our findings provide new insight concerning the intracellular networks of the PI3K/AKT and MAPK signaling cascades for regulating T. gondii-induced IL-23 and IL-12 secretion in human monocytic cells.

Elevated levels of serum IL-12 and IL-18 are associated with lower frequencies of CD4(+)CD25 (high)FOXP3 (+) regulatory t cells in young patients with type 1 diabetes

Type 1 diabetes is thought to involve chronic inflammation, which is manifested by the activation and expression of different inflammatory mediators. IL-12 and IL-18 are two cytokines that have been shown to exert strong proinflammatory activity and have been implicated in the pathogenesis of type 1 diabetes in mice and humans. The overproduction of proinflammatory mediators is controlled by specialized T cell subset, namely regulatory T cells that express FOXP3 transcription factor. Since IL-12 and IL-18 mediate inflammatory response and Tregs exhibit anti-inflammatory potential, we aimed to examine their reciprocal relationship in patients with type 1 diabetes. The study group consisted of 47 children diagnosed with type 1 diabetes and 28 healthy individuals. Serum levels of IL-12 and IL-18 were measured by ELISA, and the peripheral blood CD4⁺CD25^high FOXP3⁺ regulatory T cell frequencies were analyzed by flow cytometry. Patients with type 1 diabetes had a decreased percentage of circulating CD4⁺CD25^highFOXP3⁺ Tregs in comparison to their healthy counterparts. In addition, they produced more IL-12 and IL-18 than children from the control group. Concentrations of these cytokines positively correlated with one another, as well as with CRP and HbA1c. Moreover, the negative association between IL-12, IL-18, CRP serum levels, and the frequency of regulatory CD4⁺CD25^highFOXP3⁺ Tregs was observed. IL-12 and IL-18 may have direct or indirect impact on regulatory T cell subset, which may contribute to their reduced frequency in peripheral blood of patients with type 1 diabetes mellitus.

Identification and expression analysis of two interleukin-23α (p19) isoforms, in rainbow trout Oncorhynchus mykiss and Atlantic salmon Salmo salar

Interleukin (IL)-23 is a heterodimeric IL-12 family cytokine composed of a p19 α-chain, linked to a p40 β-chain that is shared with IL-12. IL-23 is distinguished functionally from IL-12 by its ability to induce the production of IL-17, and differentiation of Th17 cells in mammals. Three isoforms of p40 (p40a, p40b and p40c) have been found in some 3R teleosts. Salmonids also possess three p40 isoforms (p40b1, p40b2 and p40c) although p40a is missing, and two copies (paralogues) of p40b are present that have presumably been retained following the 4R duplication in this fish lineage. Teleost p19 has been discovered recently in zebrafish, but to date there is limited information on expression and modulation of this molecule. In this report we have cloned two p19 paralogues (p19a and p19b) in salmonids, suggesting that a salmonid can possess six potential IL-23 isoforms. Whilst Atlantic salmon has two active p19 genes, the rainbow trout p19b gene may have been pseudogenized. The salmonid p19 translations share moderate identities (22.8-29.9%) to zebrafish and mammalian p19 molecules, but their identity was supported by structural features, a conserved 4 exon/3 intron gene organisation, and phylogenetic tree analysis. The active salmonid p19 genes are highly expressed in blood and gonad. Bacterial (Yersinia ruckeri) and viral infection in rainbow trout induces the expression of p19a, suggesting pathogen-specific induction of IL-23 isoforms. Trout p19a expression was also induced by PAMPs (poly IC and peptidoglycan) and the proinflammatory cytokine IL-1β in primary head kidney macrophages. These data may indicate diverse functional roles of trout IL-23 isoforms in regulating the immune response in fish.

Heterogeneity of Tregs and the complexity in the IL-12 cytokine family signaling in driving T-cell immune responses in atherosclerotic vessels

The importance of immune inflammation in the development and progression of atherosclerotic lesions is well recognized. Accumulated evidence shows striking features of heterogeneity of regulatory T cells (Tregs) and the importance of the IL-12 cytokine family in regulation of Tregs in atherogenesis. The present review briefly summarized the current knowledge about the impact of the IL-12 cytokine family in regulation of immune processes in atherogenesis.

The expanding repertoire of the IL-12 cytokine family in teleost fish: Identification of three paralogues each of the p35 and p40 genes in salmonids, and comparative analysis of their expression and modulation in Atlantic salmon Salmo salar

Interleukin (IL)-12 family cytokines are heterodimers of an α-chain (p19, p28 and p35) and a β-chain (p40 and Ebi3), present as IL-12 (p35/p40), IL-23 (p19/p40), IL-27 (p28/Ebi3) and IL-35 (p35/Ebi3), and play key roles in immune responses in mammals. One p35 and up to three p40 genes have been cloned in some fish species. The identification of three active p35 genes, along with three p40 paralogues in salmonids in the current study further expands the repertoire of IL-12, IL-23 and IL-35 molecules in these species. The multiple p35 genes in teleost fish appear to have arisen via whole genome duplications. The different paralogues of the subunits are divergent, and differentially expressed and modulated by PAMPs and proinflammatory cytokines, hinting that distinct isoforms could be produced in response to infection. Therefore, the expanded IL-12 cytokine family may provide an unprecedented level of regulation to fine tune the immune response in fish.

Recombinant p35 from bacteria can form Interleukin (IL-)12, but Not IL-35

The Interleukin (IL)-12 family contains several heterodimeric composite cytokines which share subunits among each other. IL-12 consists of the subunits p40 (shared with IL-23) and p35. p35 is shared with the composite cytokine IL-35 which comprises of the p35/EBI3 heterodimer (EBI3 shared with IL-27). IL-35 signals via homo- or heterodimers of IL-12Rβ2, gp130 and WSX-1, which are shared with IL-12 and IL-27 receptor complexes, respectively. p35 was efficiently secreted in complex with p40 as IL-12 but not with EBI3 as IL-35 in several transfected cell lines tested which complicates the analysis of IL-35 signal transduction. p35 and p40 but not p35 and EBI3 form an inter-chain disulfide bridge. Mutation of the responsible cysteine residue (p40_C197A) reduced IL-12 formation and activity only slightly. Importantly, the p40_C197A mutation prevented the formation of antagonistic p40 homodimers which enabled the in vitro reconstitution of biologically active IL-12 with p35 produced in bacteria (p35_bac). Reconstitution of IL-35 with p35_bac and EBI3 did, however, fail to induce signal transduction in Ba/F3 cells expressing IL-12Rβ2 and gp130. In summary, we describe the in vitro reconstitution of IL-12, but fail to produce recombinant IL-35 by this novel approach.

Cholecystokinin octapeptide regulates the differentiation and effector cytokine production of CD4(+) T cells in vitro

Cholecystokinin octapeptide (CCK-8), an immunomodulatory peptide, can promote or suppress the development or function of specific CD4(+) T cell subsets by regulating antigen-presenting cell functions. In the current study, we investigated whether CCK-8 exerts a direct effect on T cells through influencing differentiation and cytokine production of distinct CD4(+) T cell subsets in vitro. Our results showed that CCK-8 differentially affects the development and function of CD4(+) T cell populations, with a negative influence on Th1 and Th17 cells and positive regulatory effect on inducible T regulatory cells (iTreg). Notably, CCK-8 suppressed Th1 while slightly enhancing Th2 development and cytokine production. Similarly, CCK-8 inhibited the differentiation of Th17 cells and promoted Foxp3 expression. L-364,718 and LY-288,513, selective antagonists of CCK1R and CCK2R, respectively, suppressed the effects of CCK-8 on CD4(+) T cell subset-specific transcription factors. Our findings strongly indicate that CCK-8 exerts a direct effect on T cells, which is dependent on CCKRs, particularly CCK2R. The collective results aid in further clarifying the mechanism underlying the anti-inflammatory and immunoregulatory effects of CCK-8.

Early changes in cytokine expression in peste des petits ruminants disease

Peste des petits ruminants is a viral disease of sheep and goats that has spread through most of Africa as well as the Middle East and the Indian subcontinent. Although, the spread of the disease and its economic impact has made it a focus of international concern, relatively little is known about the nature of the disease itself. We have studied the early stages of pathogenesis in goats infected with six different isolates of Peste des petits ruminants virus representing all four known lineages of the virus. No lineage-specific difference in the pathogenicity of the virus isolates was observed, although there was evidence that even small numbers of cell culture passages could affect the degree of pathogenicity of an isolate. A consistent reduction in CD4+ T cells was observed at 4 days post infection (dpi). Measurement of the expression of various cytokines showed elements of a classic inflammatory response but also a relatively early induction of interleukin 10, which may be contributing to the observed disease.

Phenotypic and functional maturation of murine dendritic cells induced by 18 alpha- and beta-glycyrrhetinic acid

Various studies have described glycyrrhizin (GL), an active triterpenoic saponin extract of licorice roots, as an anti-inflammatory, antiviral, antimicrobial, anti-tumor and immunomodulating agent. The activity of GL has been mainly attributed to its metabolites, 18-alpha (GA) and 18-beta-glycyrrhetinic acid (GB), which their mechanism of action on the immune system cells is not clearly known. In this study, we have investigated the effects of GA and GB on the immune system by targeting dendritic cells and analyzing phenotypic and functional maturity of murine dendritic cells (DCs) after treatment with these components. Stimulation of DCs with GA and GB resulted in up-regulation of CD40, CD86 and MHC-II molecules indicating their effects on the maturation of DCs. These components induced the allogenic immunostimulatory capacity of DCs by stimulating the proliferation of T cells and production of the T helper (h)1-promoting cytokine, IL-12. They also increased the production of IFN-γ by T cells in mixed-lymphocyte reaction. In conclusion, these results indicate that GA and GB may insert their immunomodulatory effects by enhancing DC maturation and modulating Th1/Th2 response through an increase in Th1 responses, implying their beneficial in host defense against infectious diseases.

Association of cytokines, high sensitive C-reactive protein, VEGF and beta-defensin-1 gene polymorphisms and their protein expressions with chronic periodontitis in the Chinese population

PURPOSES

This study aimed at investigating the association between interleukin-6 (IL-6), interleukin-12 (IL-12), C-reactive protein (CRP), vascular endothelial growth factor (VEGF) and β-defensin-1polymorphisms and the susceptibility to periodontitis in the Chinese population.

METHODS

DNA was extracted from the blood samples of 532 healthy individuals and 122 chronic periodontitis (CP) patients enrolled in the study. The genes encoding IL-6, IL-12, CRP, VEGF and β-defensin-1 were amplified using PCR and digested with restriction enzymes. The protein expression of the abovementioned genes was determined by ELISA. Differences in the allele/genotype frequencies were assessed with the chi-square test.

RESULTS

The frequencies of the C/C genotypes of IL-6, IL-12, and VEGF were higher in CP patients than healthy controls (66.3% vs 25.9%; 27.8% vs 19.9%; and 64.8% vs 52.1%, respectively). In the patients' group we also recorded frequencies of the A/A genotypes of CRP and VEGF higher than in healthy controls (63.1% vs 58.1% and 64.8% vs 35.2%, respectively). Protein production evaluated by ELISA demonstrated significant differences between CP patients and healthy controls for IL-6, IL-12, CRP, VEGF and β-defensin-1.

CONCLUSIONS

The genotypes of IL-6, IL-12, VEGF and β-defensin-1 and their protein productions were associated with CP in a Chinese population. Genotypes and serum levels of CRP were associated with CP, but alleles frequency showed no difference between CP patients and healthy controls.

Enhanced acute immune response in IL-12p35-/- mice is followed by accelerated distinct repair mechanisms in Staphylococcus aureus-induced murine brain abscess

BACKGROUND

Murine Staphylococcus aureus-mediated brain abscess comprises 2 major phases, an initial phase of cerebritis, followed by a healing phase characterized by capsule formation.

METHODS

C57BL/6 wild-type (WT) and IL-12p35(-/-) mice were intracerebrally infected with S. aureus to induce brain abscesses. Clinical disease activity and bacterial load were monitored. The cell populations that were involved, as well as their specific mediators, were analyzed by immunohistochemistry, quantitative real-time polymerase chain reaction, and flow cytometry.

RESULTS

In the acute phase, IL-12p35(-/-) mice were protected from disease. This was associated with enhanced recruitment of granulocytes, accompanied by upregulated expression of Il17a, Csf2 (which encodes granulocyte-macrophage colony-stimulating factor), Cxcl1, and Cxcl5, as well as increased expression of proinflammatory mediators, including Nos2 (which encodes inducible nitric oxide synthase), Ptgs2 (which encodes cyclooxygenase 2), and Tnf, that were primarily produced by granulocytes and activated microglia/macrophages. Furthermore, mechanisms associated with beneficial wound healing, including an accelerated formation of a fibrous capsule, were demonstrated by prominent VEGF-A production and collagen deposition driven by an earlier onset of T-helper 2 immunity in the absence of interleukin 12 (IL-12).

CONCLUSIONS

Brain abscess development is orchestrated by IL-12 at different stages of disease. Our data indicate that IL-12 has a nonprotective role in the acute phase and that IL-12 deficiency results in the accelerated formation of a protective capsule during the healing phase, which we consider crucial for early recovery from disease.

Endothelial cell adhesiveness is a function of environmental lighting and melatonin level

The endothelial layer regulates the traffic of cells and substances between the blood and tissues and plays a central role in the mounting of an inflammatory response. We have recently shown that inhibition of the nocturnal melatonin surge during the mounting of an inflammatory response primes endothelial cells to a highly reactive state, increasing the expression of adhesion molecules and inducible nitric oxide synthase (iNOS) as well as the in vitro adherence of leukocytes. Here, we investigated whether physiological variations in the plasma melatonin levels owing to the light/dark environmental cycle could also prime the reactive state of endothelial cells. Cultured endothelial cells (16-20 days) obtained from rats killed during the daytime adhere more neutrophils, expressed more adhesion molecules and iNOS, and had a higher content of the transcription factor nuclear factor kappa B (NF-kB) translocated to the nuclei. We also evaluated the expression of 84 genes (using real-time PCR array) related to the innate inflammatory response and observed a higher expression of 19 genes in cultures obtained during the daytime. In addition, the only gene that was highly expressed in cells obtained from rats killed during nighttime was one that encodes a protein that negatively modulates inflammatory response. In conclusion, the daily rhythm of melatonin also primes the ability of endothelial cells to adhere to neutrophils. This new approach for evaluating the influence of the donor on cells maintained in culture should have applications for the standardization of cell banks.

A bacterial glycan core linked to surface (S)-layer proteins modulates host immunity through Th17 suppression

Tannerella forsythia is a pathogen implicated in periodontitis, an inflammatory disease of the tooth-supporting tissues often leading to tooth loss. This key periodontal pathogen is decorated with a unique glycan core O-glycosidically linked to the bacterium's proteinaceous surface (S)-layer lattice and other glycoproteins. Herein, we show that the terminal motif of this glycan core acts to modulate dendritic cell effector functions to suppress T-helper (Th)17 responses. In contrast to the wild-type bacterial strain, infection with a mutant strain lacking the complete S-layer glycan core induced robust Th17 and reduced periodontal bone loss in mice. Our findings demonstrate that surface glycosylation of this pathogen may act to ensure its persistence in the host likely through suppression of Th17 responses. In addition, our data suggest that the bacterium then induces the Toll-like receptor 2-Th2 inflammatory axis that has previously been shown to cause bone destruction. Our study provides a biological basis for pathogenesis and opens opportunities in exploiting bacterial glycans as therapeutic targets against periodontitis and a range of other infectious diseases.

Biological activity of ovine IL-23 expressed using a foot-and-mouth disease virus 2A self-cleaving peptide

Hetero-dimeric cytokines often require equi-molar expression of both subunits to achieve biological activity. Previously, we expressed ovine IL-12 p40 and p35 linked using a self-cleaving 2A peptide from foot-and-mouth disease virus (FMDV). We now generated a new improved vector for the expression of hetero-dimeric cytokines and demonstrate the more general applicability of this strategy by cloning and expressing ovine IL-23 using the 2A peptide to link IL-12/IL-23 p40 and p19. The resulting protein was shown to be biologically active when expressed in mammalian COS cells. IL-23 plays a significant role in the differentiation of Th17 cells as well as autoimmunity and the regulation of inflammatory processes. As such this reagents will be invaluable in the unravelling of regulation of the ovine immune system for both veterinary and human animal model applications.

Cerebrospinal fluid IL-12p40, CXCL13 and IL-8 as a combinatorial biomarker of active intrathecal inflammation

Diagnosis and management of the neuroinflammatory diseases of the central nervous system (CNS) are hindered by the lack of reliable biomarkers of active intrathecal inflammation. We hypothesized that measuring several putative inflammatory biomarkers simultaneously will augment specificity and sensitivity of the biomarker to the clinically useful range. Based on our pilot experiment in which we measured 18 inflammatory biomarkers in 10-fold concentrated cerebrospinal fluid (CSF) derived from 16 untreated patients with highly active multiple sclerosis (MS) we selected a combination of three CSF biomarkers, IL-12p40, CXCL13 and IL-8, for further validation.Concentrations of IL-12p40, CXCL13 and IL-8 were determined in a blinded fashion in CSF samples from an initial cohort (n = 72) and a confirmatory cohort (n = 167) of prospectively collected, untreated subjects presenting for a diagnostic work-up of possible neuroimmunological disorder. Diagnostic conclusion was based on a thorough clinical workup, which included laboratory assessment of the blood and CSF, neuroimaging and longitudinal follow-up. Receiver operating characteristic (ROC) curve analysis in conjunction with principal component analysis (PCA), which was used to combine information from all three biomarkers, assessed the diagnostic value of measured biomarkers.Each of the three biomarkers was significantly increased in MS and other inflammatory neurological disease (OIND) in comparison to non-inflammatory neurological disorder patients (NIND) at least in one cohort. However, considering all three biomarkers together improved accuracy of predicting the presence of intrathecal inflammation to the consistently good to excellent range (area under the ROC curve = 0.868-0.924).Future clinical studies will determine if a combinatorial biomarker consisting of CSF IL-12p40, CXCL13 and IL-8 provides utility in determining the presence of active intrathecal inflammation in diagnostically uncertain cases and in therapeutic development and management.

Monocytes expression of IL-12 related and IL-10 genes in association with development of colorectal cancer

The main regulator of anti-tumor immune response is the activity of monocytes, suggesting that the produced cytokines may have a prognostic role. This study investigates gene expression of interleukin (IL)-12-related cytokine and IL-10 in stimulated monocytes from colorectal cancer (CRC) patients. Relative quantification of IL-12A, IL-12B, IL-23A and IL-10 mRNA transcripts was performed on the third hours after stimulation by real-time qPCR. We also explored an inhibitor of JNK signaling pathway activation for the observed cytokine gene expression. A strong downregulation of IL-12B mRNA expression in CRC monocytes compared to healthy donors was observed. The rate of transcription of IL-12B in stimulated monocytes was associated with the stage of CRC. The expression of IL-12A gene in stimulated monocytes from patients with advanced was lower than early cancer. Moreover, we observed stage dependent JNK inhibition mediated reduction in IL-12A expression. The hyporesponsiveness was strongly expressed in monocytes from advanced then early stages of CRC. Expression of IL-10 mRNA was almost equally in CRC monocytes from early stages and healthy donors. We demonstrated that altered gene expression profiles of IL-12A, IL-12B, IL-23A at mRNA level in CRC monocytes was associated with tumor development and can be attributed to anticancer immune response.

Enhanced expression of IL-10 in contrast to IL-12B mRNA in poultry with experimental coccidiosis

Interleukin (IL)-12 and IL-10 are immunoregulatory cytokines with an antagonistic effect on the T-helper (Th)1/Th2 cytokine balance and they provide a functional link between innate resistance and the adaptive immune response. This investigation was conducted to determine the expression of IL-10 and IL-12B mRNA levels in chickens' gut mucosa infected with Eimeria tenella and in sulfachlorpyrazine-sodium treated animals after infection. Broiler chickens were randomly allocated in three groups: healthy untreated control; infected untreated animals and infected, treated with sulfachlorpyrazine sodium chickens 6 days after the challenge with an E. tenella. Quantitative real time PCR analysis was performed using specific primer pairs and probes for IL-10 and IL-12B. The expression of IL-10 mRNA was greater in the duodenum then in the caecum and the liver of healthy chickens. E. tenella infection led to significant up-regulation of IL-10 mRNA in the caecum, followed by mRNA in the liver. A significant down regulation was observed mainly in the caecum after the treatment with sulfachlorpyrazine. In contrast, IL-12B expression in all investigated tissues remained insignificantly affected in the studied groups of animals. Distinct up-regulation of IL-10 mRNA, after the challenge with E. tenella, in the caecum can be attributed to the tissue tropism of Eimeria spp. The production of IL-12 is regulated by negative feedback through IL-10 which explains lack of increase in IL-12B mRNA. Sulfonamide treatment resulted in clinical improvement and restoration of IL-10 mRNA to the levels observed in healthy chickens.

The impact of cytokine gene polymorphisms on Epstein-Barr virus infection outcome in pediatric liver transplant recipients

BACKGROUND

Epstein-Barr virus (EBV) is associated with most cases of the post-transplant lymphoproliferative disorders developed during the first year after transplantation. The high EBV DNA load constitutes a major risk for the development of EBV-related lymphoproliferations. However, among transplant recipients there are patients with a chronically high viral load (CHVL) who do not develop lymphoproliferations. The polymorphism within cytokine genes might influence the susceptibility to, and contribute to the pathogenesis of the disease.

OBJECTIVES

The aim of this study was to analyze the genetic polymorphism in the selected cytokines with regard to EBV infection outcome in children after liver transplantation (LTx).

STUDY DESIGN

Thirteen cytokine/cytokine receptor polymorphisms were genotyped in 170 children after LTx, and related to: EBV DNAemia, CHVL onset and the length of CHVL carriage.

RESULTS

The study revealed: the protective effect of rare homozygous and heterozygous IL-1β-511 and IL-1 receptor antagonist (IL-1RN VNTR) genotypes against viremia within the first year after LTx (OR=0.28, p=0.0007 and OR=0.35, p=0.009, respectively); the protective effect of CC chemokine ligand 2 (CCL2)+1543CT and TT genotypes against CHVL onset (OR=0.38, p=0.042); and the prolonged CHVL-resolution in IL12B 3'untranslated region (3'UTR) AC individuals (p=0.034).

CONCLUSIONS

This data suggests that carriage of IL-1β-511CT/TT and/or IL-1RN VNTR 1.2/2.2 genotype may be beneficial for combating EBV infection. This is the first study reporting the association of CCL2 and IL12B gene polymorphisms with the CHVL carriage in pediatric LTx recipients.

Homeostatic regulation of Salmonella-induced mucosal inflammation and injury by IL-23

IL-12 and IL-23 regulate innate and adaptive immunity to microbial pathogens through influencing the expression of IFN-γ, IL-17, and IL-22. Herein we define the roles of IL-12 and IL-23 in regulating host resistance and intestinal inflammation during acute Salmonella infection. We find that IL-23 alone is dispensable for protection against systemic spread of bacteria, but synergizes with IL-12 for optimal protection. IL-12 promotes the production of IFN-γ by NK cells, which is required for resistance against Salmonella and also for induction of intestinal inflammation and epithelial injury. In contrast, IL-23 controls the severity of inflammation by inhibiting IL-12A expression, reducing IFN-γ and preventing excessive mucosal injury. Our studies demonstrate that IL-23 is a homeostatic regulator of IL-12-dependent, IFN-γ-mediated intestinal inflammation.

Plasticity and cross-talk of interleukin 6-type cytokines

Interleukin (IL)-6-type cytokines are critically involved in health and disease. The duration and strength of IL-6-type cytokine-mediated signaling is tightly regulated to avoid overshooting activities. Here, molecular mechanisms of inter-familiar cytokine cross-talk are reviewed which regulate dynamics and strength of IL-6 signal transduction. Both plasticity and cytokine cross-talk are significantly involved in pro- and anti-inflammatory/regenerative properties of IL-6-type cytokines. Furthermore, we focus on IL-6-type cytokine/cytokine receptor plasticity and cross-talk exemplified by the recently identified composite cytokines IL-30/IL-6R and IL-35, the first inter-familiar IL-6/IL-12 family member. The complete understanding of the intra- and extracellular cytokine networks will aid to develop novel tailor-made therapeutic strategies with reduced side effects.

Role of CD40 ligation in dendritic cell semimaturation

Background

DC are among the first antigen presenting cells encountering bacteria at mucosal surfaces, and play an important role in maintenance of regular homeostasis in the intestine. Upon stimulation DC undergo activation and maturation and as initiators of T cell responses they have the capacity to stimulate naïve T cells. However, stimulation of naïve murine DC with B. vulgatus or LPS at low concentration drives DC to a semimature (sm) state with low surface expression of activation-markers and a reduced capacity to activate T-cells. Additionally, semimature DC are nonresponsive to subsequent TLR stimulation in terms of maturation, TNF-α but not IL-6 production. Ligation of CD40 is an important mechanism in enhancing DC maturation, function and capacity to activate T-cells. We investigated whether the DC semimaturation can be overcome by CD40 ligation.

Results

Upon CD40 ligation smDC secreted IL-12p40 but not the bioactive heterodimer IL-12p70. Additionally, CD40 ligation of smDC resulted in an increased production of IL-6 but not in an increased expression of CD40. Analysis of the phosphorylation pattern of MAP kinases showed that in smDC the p38 phosphorylation induced by CD40 ligation is inhibited. In contrast, phosphorylation of ERK upon CD40 ligation was independent of the DC maturation state.

Conclusion

Our data show that the semimature differentiation state of DC can not be overcome by CD40 ligation. We suggest that the inability of CD40 ligation in overcoming DC semimaturation might contribute to the tolerogenic phenotype of semimature DC and at least partially account for maintenance of intestinal immune homeostasis.

Mannan oligosaccharide increases serum concentrations of antibodies and inflammatory mediators in weanling pigs experimentally infected with porcine reproductive and respiratory syndrome virus

Mannan-containing products are capable of modulating immune responses in animals. However, different products may have diverse immunomodulation. The experiment was conducted to examine effects of mannan oligosaccharide (Actigen; ACT) on growth performance and serum concentrations of antibodies and inflammatory mediators in weanling pigs (Sus scrofa) experimentally infected with porcine reproductive and respiratory syndrome virus (PRRSV). A total of 32 PRRSV-negative pigs (3 wk old) were randomly assigned from within blocks to 1 of 4 treatments in a 2 by 2 factorial arrangement [2 types of diet: control (0%) and ACT addition (0.04%); and with and without PRRSV] in a randomized complete block design. Pigs were blocked by initial BW within sex. Ancestry was equalized across treatments. Pigs (8/treatment) were kept individually in each pen. After 2 wk of an 8-wk period of feeding the treatments, pigs received an intranasal inoculation of PRRSV or sham medium at 5 wk of age. Infection by PRRSV decreased ADG, ADFI, and G:F throughout the experiment (P < 0.01). Actigen did not affect ADG (P = 0.450), but decreased (P = 0.047) ADFI from 28 to 42 days postinoculation (DPI). During that time, ACT improved G:F in infected pigs but not in sham controls (interaction, P = 0.009). Dietary ACT did not affect viremia in infected pigs (P > 0.05), but increased PRRSV-specific antibody titer at 35 DPI (P = 0.042). Infection with PRRSV induced the febrile responses of pigs from 3 to 10 DPI (P < 0.001) with return to normal at 14 DPI. During the experimental period, the rectal temperature of pigs was found slightly elevated by ACT (P = 0.045). Infected pigs had greater serum concentrations of IL-1β, tumor necrosis factor (TNF)-α, IL-12, interferon (IFN)-γ, IL-10, and haptoglobin (Hp) than sham controls (P < 0.001). These results indicate that PRRSV stimulated secretion of cytokines involved in innate, T-helper 1, and T-regulatory immune responses. Actigen tended to decrease the serum TNF-α concentration regardless of PRRSV (P = 0.058). The ACT × PRRSV interaction was significant for IL-1β (P = 0.016), IL-12 (P = 0.026), and Hp (P = 0.047), suggesting that infected pigs fed ACT had greater serum concentrations of these mediators than those fed the control. The increases in IL-1β and IL-12 may favorably promote innate and T-cell immune functions in infected pigs fed ACT. Feeding ACT may be useful as ACT is related to increased PRRSV antibody titers and G:F in infected pigs at certain times during infection.

Macrophage-produced IL-12p70 mediates hemorrhage-induced damage in a complement-dependent manner

Hemorrhage and hemorrhagic shock instigate intestinal damage and inflammation. Multiple components of the innate immune response, including complement and neutrophil infiltration, are implicated in this pathology. To investigate the interaction of complement activation and other components of the innate immune response during hemorrhage, we treated mice after hemorrhage with CR2-fH, a targeted inhibitor of the alternative complement pathway and assessed intestinal damage and inflammation 2 h after hemorrhage. In wild-type mice, CR2-fH attenuated hemorrhage-induced, midjejunal damage and inflammation as determined by decreased mucosal damage, macrophage infiltration, leukotriene B4, IL-12p40, and TNF-[alpha] production. The critical nature of intestinal macrophage infiltration and activation in the response to hemorrhage was further determined using mice pretreated with clodronate-containing liposomes. The absence of either macrophages or IL-12p70 attenuated intestinal damage. These data suggest that complement activation and macrophage infiltration with IL-12p70 production are critical to hemorrhage-induced midjejunal damage and inflammation.

EBI3 deficiency leads to diminished T helper type 1 and increased T helper type 2 mediated airway inflammation

Despite extensive investigation of the signals required for development of T helper type 1 (Th1) and type 2 (Th2) immune responses, the mechanisms involved are still not well-defined. A critical role for Epstein-Barr virus-induced gene 3 (EBI3) in these responses has been proposed. EBI3, initially discovered as a transcriptionally activated gene in Epstein-Barr virus-infected B lymphocytes, codes for a subunit of the cytokine interleukin-27 (IL-27). While initial studies suggested that it had an important role in promoting Th1 responses, subsequent studies have revealed that EBI3 receptor signalling influences a variety of immune cell types and can inhibit both Th1 and Th2 responses. In the present study, we evaluated EBI3(-/-) mice for their ability to mount both Th1-mediated and Th2-mediated airway inflammatory responses. The EBI3(-/-) mice sensitized by exposure to inhaled ovalbumin plus a high dose of lipopolysaccharide, which normally results in Th1 responses in wild-type (WT) mice, instead developed Th2 type airway inflammation, with increased numbers of eosinophils. The EBI3(-/-) mice that were exposed to inhaled ovalbumin with a low dose of lipopolysaccharide, which induces Th2 responses in WT mice, showed a marked enhancement of these responses, with increased airway eosinophils, increased serum IgE levels and increased levels of Th2 cytokines (IL-4, IL-5 and IL-13) in culture supernatants of mediastinal lymph node cells. Increased production of Th2 cytokines was also seen when naive CD4(+) T cells from EBI3(-/-) mice were stimulated in vitro compared with cells from WT mice. These results provide the first evidence that EBI3 may play an inhibitory role in allergic asthma development.

gp130 on macrophages/granulocytes modulates inflammation during experimental tuberculosis

gp130 is a common receptor chain for cytokines such as interleukin (IL)-27 and IL-6. During experimental tuberculosis (TB), IL-27 prevents optimal antimycobacterial protection and limits the pathological sequelae of chronic inflammation. The anti-inflammatory properties of IL-27 have been attributed mainly to its suppressive effect on T helper (TH) cells. However, because gp130 cytokines also suppress the inflammatory immune response of macrophages, IL-27 may also regulate inflammation by limiting the secretion of pro-inflammatory cytokines. To specifically address the role of gp130 cytokines on macrophages, the outcome of experimental TB was analysed in macrophage/neutrophil-specific gp130-deficient (LysM(cre) gp130(loxP/loxP)) mice. In these mice, the enhanced induction of inflammatory cytokines and increased expression of the inducible nitric oxide synthase (NOS2) and LRG47 was linked to a greatly augmented TH17 immune response and matrix metalloproteinase (MMP)-9 expression. However, this amplified inflammatory immune response in Mtb-infected LysM(cre) gp130(loxP/loxP) mice was not associated with reduced bacterial loads and/or accelerated pathology. Our study revealed an immunoregulatory function of gp130 cytokines on macrophages/granulocytes, which is, however, not critical for modulating the outcome of TB.

Therapeutic approaches to multiple sclerosis: an update on failed, interrupted, or inconclusive trials of immunomodulatory treatment strategies

Multiple sclerosis (MS) continues to be a therapeutic challenge, and much effort is being made to develop new and more effective immune therapies. Particularly in the past decade, neuroimmunologic research has delivered new and highly effective therapeutic options, as seen in the growing number of immunotherapeutic agents and biologics in development. However, numerous promising clinical trials have failed to show efficacy or have had to be halted prematurely because of unexpected adverse events. Some others have shown results that are of unknown significance with regard to a reliable assessment of true efficacy versus safety. For example, studies of the highly innovative monoclonal antibodies that selectively target immunologic effector molecules have not only revealed the impressive efficacy of such treatments, they have also raised serious concerns about the safety profiles of these antibodies. These results add a new dimension to the estimation of risk-benefit ratios regarding acute or long-term adverse effects. Therapeutic approaches that have previously failed in MS have indicated that there are discrepancies between theoretical expectations and practical outcomes of different compounds. Learning from these defeats helps to optimize future study designs and to reduce the risks to patients. This review summarizes trials on MS treatments since 2001 that failed or were interrupted, attempts to analyze the underlying reasons for failure, and discusses the implications for our current view of MS pathogenesis, clinical practice, and design of future studies. In order to maintain clarity, this review focuses on anti-inflammatory therapies and does not include studies on already approved and effective disease-modifying therapies, albeit used in distinct administration routes or under different paradigms. Neuroprotective and alternative treatment strategies are presented elsewhere.