IL-17 producing cells in host defense and atopy

The role of the endometrial microbiome in embryo implantation and recurrent implantation failure

There is a suggested pathophysiology associated with endometrial microbiota in cases where repeated implantation failure of high-quality embryos is observed. However, there is a suspected association between endometrial microbiota and the pathogenesis of implantation failure. However, there is still a lack of agreement on the fundamental composition of the physiological microbiome within the uterine cavity. This is primarily due to various limitations in the studies conducted, including small sample sizes and variations in experimental designs. As a result, the impact of bacterial communities in the endometrium on human reproduction is still a subject of debate. In this discourse, we undertake a comprehensive examination of the existing body of research pertaining to the uterine microbiota and its intricate interplay with the process of embryo implantation.

Genetic and Genomic Analysis of Cow Mortality in the Israeli Holstein Population

“Livability” was defined as the inverse of the probability of death. The objectives of this study were to estimate the heritability, genetic and phenotypic trends for the livability of Israeli Holstein cows; estimate the genetic and environmental correlations between livability and the nine traits included in the Israeli breeding index; estimate the effect of the inclusion of livability in the Israeli breeding index on expected genetic gains; and compute a genome-wide association study (GWAS) for livability. Seven data sets were analyzed. All data were derived from the database of the Israeli dairy cattle herd-book. The mean livability for the complete data set of 523,954 cows born from 2000 through 2016 was 89.6%. Pregnancy reduced livability by 15%. Livability generally increased with parity and days in milk within parity. Heritability of livability was 0.0082. Phenotypic and genetic trends over the 14-year period from 2000 through 2013 were −0.42% and −0.22% per year. If livability is included in the Israeli breeding index, accounting for 9% of the index, livability would increase by 1.3% and protein production would decrease by 11 kg over the next decade, as compared to the current index. A marker in proximity to the oxytocin–vasopressin locus had the greatest effect in the GWAS. Oxytocin activity in cattle affects calving-associated pathologies and maternal death. Inclusion of livability in the Israeli breeding index is not recommended.

Genetic polymorphisms in immune- and inflammation-associated genes and their association with bovine mastitis resistance/susceptibility

Bovine mastitis, the inflammation of the mammary gland, is a contagious disease characterized by chemical and physical changes in milk and pathological changes in udder tissues. Depressed immunity and higher expression of inflammatory cytokines with an elevated milk somatic cell count can be observed during mastitis in dairy cattle. The use of somatic cell count (SCC) and somatic cell score (SCS) as correlated traits in the indirect selection of animals against mastitis resistance is in progress globally. Traditional breeding for mastitis resistance seems difficult because of the low heritability (0.10-0.16) of SCC/SCS and clinical mastitis. Thus, genetic-marker-selective breeding to improve host genetics has attracted considerable attention worldwide. Moreover, genomic selection has been found to be an effective and fast method of screening for dairy cattle that are genetically resistant and susceptible to mastitis at a very early age. The current review discusses and summarizes the candidate gene approach using polymorphisms in immune- and inflammation-linked genes (CD4, CD14, CD46, TRAPPC9, JAK2, Tf, Lf, TLRs, CXCL8, CXCR1, CXCR2, C4A, C5, MASP2, MBL1, MBL2, LBP, NCF1, NCF4, MASP2, A2M, and CLU, etc.) and their related signaling pathways (Staphylococcus aureus infection signaling, Toll-like receptor signaling, NF-kappa B signaling pathway, Cytokine-cytokine receptor, and Complement and coagulation cascades, etc.) associated with mastitis resistance and susceptibility phenotypic traits (IL-6, interferon-gamma (IFN-γ), IL17, IL8, SCS, and SCC) in dairy cattle.

Evolutional perspective and functional characteristics of interleukin-17 in teleosts

Interleukin (IL)-17 is a proinflammatory cytokine and plays essential roles in adaptive and innate immune responses against bacterial and fungal infections. Especially in mammalian mucosal tissues, it is well known that innate immune responses via IL-17A and IL-17F, such as the production of antimicrobial peptides, are very important for microbiota control. In contrast, interesting insights into the functions of IL-17 have recently been reported in several teleost species, although little research has been conducted on teleost IL-17. In the present review, we focused on current insights on teleost IL-17 and speculated on the different or consensus parts of teleost IL-17 signaling compared to that of mammals. This review focuses on the role of teleost IL-17 in intestinal immunity. We expect that this review will encourage a further understanding of the roles and importance of IL-17 signaling in teleosts.

LncRNA HCP5 Participates in the Tregs Functions in Allergic Rhinitis and Drives Airway Mucosal Inflammatory Response in the Nasal Epithelial Cells

Allergic rhinitis (AR) is an allergic disease characterized as (immunoglobulin, IgE)-mediated type I hypersensitivity disorder. Regulatory T cells (Tregs) play a crucial role in AR. In the present study, we aimed to investigate the mechanism of how Tregs are regulated by long noncoding RNA HCP5 and the regulatory role of HCP5 in IL-13-induced inflammatory response in nasal epithelial cells (NECs) from AR patients. Peripheral blood mononuclear cells (PBMCs) and NECs were obtained from collected blood samples and nasal epithelial tissues. CD4+ T cells and Tregs were purified using certain cell isolation kits from PBMCs and Tregs were also differentiated from CD4+ T cells using recombinant human IL-2 and TGF-β. The expression levels of HCP5, miR-16, ATXN2L, GM-CSF, eotaxin, and MUC5AC were detected by real-time PCR and western blot. The concentrations of inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). The interaction among HCP5, miR-16, and ATXN2L were verified by dual-luciferase reporter assay. lncRNA HCP5 expression dramatically downregulated in PBMCs, CD4+ T cells, Tregs, and nasal tissues of AR patients, as well as in IL-13-treated NECs. HCP5 promoted Tregs differentiation and proliferation via targeting miR-16/ATXN2L axis. Additionally, HCP5 inhibited IL-13-induced GM-CSF, eotaxin, and MUC5AC production in NECs. HCP5 sponged miR-16 and negatively regulated its expression, and miR-16 targeted ATXN2L and inhibition of miR-16 suppressed IL-13-induced GM-CSF, eotaxin, and MUC5AC expression. HCP5/miR-16/ATXN2L axis mediated Tregs proliferation and functions in AR. Besides, the regulation of IL-13-induced dysfunction of NECs by lncRNA HCP5 depended on miR-16/ATXN2L in the inflammatory response of AR.

Effectiveness of ustekinumab in patients with atopic dermatitis: analysis of real-world evidence

INTRODUCTION

Atopic dermatitis (AD) is a very common chronic inflammatory skin disease. Ustekinumab is a human monoclonal antibody approved for psoriasis, that targets the p40 subunit shared by interleukin (IL)-12 and IL-23, cytokines which may also play a role in AD. Administration of ustekinumab in AD has been presented in anecdotal reports with conflicting results. Our aim was to evaluate the precise value of this biologic drug on AD in real-world setting.

MATERIAL AND METHOD

We sistematically reviewed published data and analyzed aggregated results involving AD treated with ustekinumab. The main outcome was clinical improvement reported by each record. We classified this in three categories: "complete response", "partial response" and "no response". A multivariant model was used to assess association between response to ustekinumab and the following potential predictive factors: gender, age (age < or >50), duration of AD, history of asthma, previous use of biologic drugs, number of previous systemic therapies, serum levels of IgE and duration of ustekinumab therapy.

RESULTS

Data on 23 patients from eight articles were analyzed. Complete AD remission was reported in 8 patients (34.8%), while abscense of response was observed also in 8 patients (34.8%). Partial response was reported in 7 patients (30.4%). No differences were observed with respect to age, gender, history of asthma, naïve patient, duration of AD or duration of ustekinumab therapy.

CONCLUSION

We conclude from available data the IL-12/23 pathway is likely not an atractive target for AD. More no convincing data exist arguing against consideration of ustekinumab in AD patients. Other effective treatments are available and should be prioritized with good safety profile. Limitations are yet low number of studies and patients.WHAT'S ALREADY KNOWN ABOUT THIS TOPIC?Administration of ustekinumab in AD (atopic dermatitis) has been presented in anecdotical reports with conflicting resultsWHAT DOES THIS STUDY ADD?This work presents the largest cohort of AD patients treated with ustekinumab in a real-world setting.Ustekinumab resulted in similar rates of complete, partial and negative responses.Our findings demonstrate the IL-12/23 pathway is not an atractive target in AD.More novel and effective treatments for AD are available and should be prioritized.The impact of anti IL-12/IL-23p40 therapy in AD is still unclarified due to limited controlled trials.

Protective effect of Asarum sieboldii essential oil on ovalbumin induced allergic rhinitis in rat

BACKGROUND

The study was aimed to investigate the protective effect of Asarum sieboldii Miq. essential oil (AEO) on ovalbumin (OVA)-induced allergic rhinitis (AR) in rats.

METHODS AND RESULTS

Sixty Sprague-Dawley male rats were randomly divided into six groups (n=10): control, model, cetirizine (Cet, 4.65 g/kg), and AEO (0.5, 1.5, 3 g/kg) groups. All animals except the control group received repeated intranasal instillation with 20 μl of 20% OVA in Al(OH)3 saline solvent for 15 days. The control group was intranasally instilled with 5 mg/ml of Al(OH)3 instead of the same procedure. In the 15 days, Cet and AEO were orally administrated for 28 days. At the end of the drug administration, 20 μl of 5% OVA was given to animals to stimulate allergic reaction, then the rat behavioral detection, assessment of the patho-morphological changes in nasal mucosa, and the serum biomarkers were determined. The result showed that AEO could significantly reduce the amount of nasal secretions, sneezing, and the degree of nasal scratching in AR rats with EC50 = 1.5 and 2.8 g/kg, respectively. The degree of nasal mucosal inflammation in AEO group improved, the levels of immunoglobulin E (IgE), histamine, IL-4, IL-5, IL-17 were decreased, and the level of IFN-γ was increased obviously with EC50 = 2 g/kg.

CONCLUSION

The study suggested that the possible mechanism might be related with the inhibition of histamine release and regulation of the cytokine levels, which plays an important role in the treatment of AR.

Role of the JAK-STAT Pathway in Bovine Mastitis and Milk Production

Simple Summary

The cytokine-activated Janus kinase (JAK)—signal transducer and activator of transcription (STAT) pathway has an important role in the regulation of immunity and inflammation. In addition, the signaling of this pathway has been reported to be associated with mammary gland development and milk production. Because of such important functions, the JAK-STAT pathway has been widely targeted in both human and animal diseases as a therapeutic agent. Recently, the JAK2, STATs, and inhibitors of the JAK-STAT pathway, especially cytokine signaling suppressors (SOCSs), have been reported to be associated with milk production and mastitis-resistance phenotypic traits in dairy cattle. Thus, in the current review, we attempt to overview the development of the JAK-STAT pathway role in bovine mastitis and milk production.

Abstract

The cytokine-activated Janus kinase (JAK)—signal transducer and activator of transcription (STAT) pathway is a sequence of communications between proteins in a cell, and it is associated with various processes such as cell division, apoptosis, mammary gland development, lactation, anti-inflammation, and immunity. The pathway is involved in transferring information from receptors on the cell surface to the cell nucleus, resulting in the regulation of genes through transcription. The Janus kinase 2 (JAK2), signal transducer and activator of transcription A and B (STAT5 A & B), STAT1, and cytokine signaling suppressor 3 (SOCS3) are the key members of the JAK-STAT pathway. Interestingly, prolactin (Prl) also uses the JAK-STAT pathway to regulate milk production traits in dairy cattle. The activation of JAK2 and STATs genes has a critical role in milk production and mastitis resistance. The upregulation of SOCS3 in bovine mammary epithelial cells inhibits the activation of JAK2 and STATs genes, which promotes mastitis development and reduces the lactational performance of dairy cattle. In the current review, we highlight the recent development in the knowledge of JAK-STAT, which will enhance our ability to devise therapeutic strategies for bovine mastitis control. Furthermore, the review also explores the role of the JAK-STAT pathway in the regulation of milk production in dairy cattle.

HDAC inhibitor sodium butyrate prevents allergic rhinitis and alters lncRNA and mRNA expression profiles in the nasal mucosa of mice

Our previous study demonstrated that intranasal administration of histone deacetylase inhibitor sodium butyrate (NaB) exhibits therapeutic effects on a mouse model of allergic rhinitis (AR). However, whether NaB is effective on AR when administered orally and prophylactically, as well as its potential effects on gene expression, remained unknown. The present study aimed to investigate the preventive effect of NaB on AR when added to the diet of newly weaned mice and to evaluate the changes in long non-coding (lnc)RNA and mRNA expression profiles in the nasal mucosa. Mice were randomly divided into three groups as follows: i) Control (C) group, (no treatment); ii) AR group [treated with ovalbumin (OVA)]; and iii) NaB + AR group (treated with OVA and NaB). The NaB + AR group was administered NaB in their feed (30 g/kg chow), whereas the other two groups were fed normal feed between 3 and 6 weeks of age. At 7 weeks of age, OVA administration was initiated to induce AR in the AR and NaB + AR groups. Following model establishment, behavioral assessments, western blotting and gene expression analysis were performed. NaB exhibited a preventive effect in the murine AR model, diminished the increases in histone deacetylase 1 (HDAC1) and HDAC8 expression and increased OVA-induced acetylation of histone H3 at lysine 9. In addition, NaB increased the AR-associated low expression of interleukin 2 (IL-2), interferon γ and IL-17 and decreased the expression of IL-4, IL-5 and transforming growth factor β1. Gene Ontology and pathway analyses revealed the top 10 pathways among the groups. Octamer-binding transcription factor 1, ecotropic viral integration site 1 and paired box 4 were predicted to be target genes of lncRNA (NONMMUT057309). Thus, NaB may exhibit a preventive effect on AR. Additionally, the lncRNA and mRNA expression profiles in the nasal mucosa of mice with AR differed significantly following NaB treatment. These results may provide insights into the pathogenesis of AR and suggest new treatment targets.

Preclinical development of GR1501, a human monoclonal antibody that neutralizes interleukin-17A

Interleukin-17A (IL-17A) is a soluble pro-inflammatory cytokine, which is mainly secreted by Th17 cells. In humans, IL-17A mRNA and protein levels are increased in several autoimmune diseases, including psoriasis and rheumatoid arthritis. This study describes the preclinical in vitro and in vivo characterization of GR1501, a human IL-17A-neutralizing IgG4 monoclonal antibody. GR1501 binds human, rhesus and cynomolgus IL-17A with high affinity but does not bind to mouse IL-17A or other IL-17 family members. GR1501 effectively blocks the interaction between IL-17A and its receptor IL-17RA, thereby inhibiting IL-17A-induced CXCL1 and IL-6 release in cells and mice. In mouse air pouch model, GR1501 effectively inhibits IL-17A induced leukocytes infiltration into the air pouch. GR1501 also reduces joint swelling and inflammation in mouse arthritis model. These data suggest that GR1501 is a potent and selective IL-17A-neutralizing monoclonal antibody and will support the clinical investigation of this monoclonal antibody in psoriasis and rheumatoid arthritis.

Efficacy and safety of sublingual dust mite drops in children with mono- or polysensitized allergic rhinitis

OBJECTIVE

To explore the efficacy and safety of sublingual house dust mite (HDM) drops in children with mono- or polysensitized allergic rhinitis.

METHODS

We conducted a retrospective cohort study of 65 children with monosensitized AR and 118 children with polysensitized AR who were scheduled for sublingual administration of HDM drops from January 2015 to June 2016. Interleukin (IL)-2, IL-4, and IL-17α, transforming growth factor-β1 (TGF-β1), specific immunoglobulin E (IgE), and specific IgG4 were detected by ELISA. The efficacies were assessed using symptoms score and medication score. All the outcomes were measured 1 month before the study and 1 month after the end of the 2-year treatment.

RESULTS

The total nasal symptoms score (TNSS) decreased significantly from 11.27 (9.81 ± 12.73) at baseline to 3.48(1.98 ± 4.98) at the end of sublingual treatment for the monosensitized AP group (t = 30.00, P < 0.01), and from 11.54(10.04 ± 13.04) to 3.56 (2.00 ± 5.16) for the polysensitized AR group (t = 40.05, P < 0.01), respectively. IL-2 and TGF-β1 increased significantly after treatment in contrast with before treatment in both the monosensitized group and the polysensitized group (both P < 0.01). In contrast, IL-4 and IL-17α decreased significantly after treatment compared with the baseline in both groups (both P < 0.01). Sublingual HDM drops were generally safe and well tolerant in both groups.

CONCLUSIONS

This study confirmed the efficacy and safety of sublingual AIT in both monosensitized and polysensitized AR patients (Chinese children).

Th17 cells in Bulgarian children with chronic obstructive lung diseases

INTRODUCTION AND OBJECTIVES

Th17 lymphocytes are now widely believed to be critical in various chronic pulmonary diseases. However, there is still a small number of investigations regarding children. We aimed to assess the percentage of Th17 lymphocytes and IL-17A in peripheral blood of children with chronic obstructive lung diseases.

PATIENTS AND METHODS

We included a total of 42 children: 20 with bronchial asthma (BA), 12 with cystic fibrosis (CF) and 10 healthy children without a history of allergies, aged 4-17 years. Th17 cells (CD3+CD4+CD161+CCR6+) were determined in peripheral blood by flow cytometry. The concentration of serum IL-17A was measured by ELISA.

RESULTS

The BA patients had a significantly higher percentage of Th17 (12.40±1.16%) compared to the CF children (7.64±0.87%, p=0.0035) and healthy (7.25±0.45%, p=0.008). Stratifying the BA group, we found higher levels of Th17 in patients with severe BA (p=0.03), whereas patients with moderate BA had Th17 cells close to those in CF and healthy children. We found that patients with better control of BA had Th17 closer to those with CF (p=0.98) than BA children with poor control (p<0.001) (post hoc, Bonferroni correction). CF patients with concomitant P. aeruginosa infection showed slightly higher percentages of Th17 cells than those without infection (8.08±3.09% vs. 6.25±2.42%, p=0.294).

CONCLUSIONS

The percentage of Th17 cells was significantly increased in the peripheral blood of children with severe BA compared to the children with moderate BA, which suggests that the former could possibly benefit from future target therapies.

TGF-Β as a Marker of Ulcerative Colitis and Disease Severity

Ulcerative colitis (UC) represents chronic inflammation of the large intestine. Immune response plays an important role in disease genesis and progression. Activated leukocytes secrete several cytokines that actively regulate the inflammatory response in UC. The aim of this study was to determine levels of cytokines IL-17, IL-27, IFN-γ and TGF-β in patients with UC and to test them as biomarkers for disease.

The blood samples of 24 patients with ulcerative colitis without previous treatment and 37 healthy individuals were analyzed. Serum levels of IL-17, IL-27, IFN-γ and TGF-β were measured using sensitive enzyme-linked immunosorbent assay (ELISA) kits.

Serum levels of IL-17, IL-27, IFN-γ and TGF-β were increased in patients with UC, compared to healthy controls (p=0.022; p=0.001; p=0.001; and p=0.002; respectively). Ratios of cytokines IL-27/IL-17, IFN-γ/TGF-β and IL-17/TGF-β were significantly higher in group of patients with UC (p=0.002; p=0.002; p=0.003; respectively). Serum value of TGF-β higher than 20 pg/ml presents a highly sensitive and specific marker for UC.

We believe that increased production and predominance of immunosupressive TGF-β may represent compensatory mechanism for ongoing pro-inflammatory processes in UC.

Risk of allergic conjunctivitis in patients with type 1 diabetes mellitus: a population-based retrospective cohort study

OBJECTIVE

In accordance with the dichotomy between T helper type 1(Th1) and T helper type 2 (Th2) responses, the occurrence of allergic conjunctivitis (AC) and type 1 diabetes mellitus (T1DM) is, in theory, inversely related in the individual. However, recent studies investigating the association between the two diseases are controversial.

DESIGN

Population-based cohort study.

SETTING

We used claims data of the National Health Insurance Research Database of Taiwan.

PARTICIPANTS

We identified 4160 patients aged 1-30 years with newly diagnosed T1DM and no history of AC at baseline. For each patient with T1DM, four non-T1DM controls (n=16,640) were matched by sex. The mean follow-up time was 6 years.

PRIMARY AND SECONDARY OUTCOME MEASURES

Multivariate Cox proportional hazards regression analysis was used to evaluate the risk of AC. We additionally evaluated the association between risk of AC and T1DM progression by examining Diabetes Complications Severity Index (aDCSI) changes from the date of diagnosis until the end of follow-up.

RESULTS

The overall incidence of allergic conjunctivitis (AC) was higher in the type 1 diabetes mellitus (T1DM) cohort than in the control cohort (23.0 vs 13.5 per 1000 person-years, adjusted incidence rate ratio (aIRR): 1.59, 95% CI 1.47 to 1.71). Relative to that in patients with mildly progressive T1DM, the risk of AC increased as the adapted Diabetes Complications Severity Index (aDCSI) increased (aIRR: 1.68, 3.78 and 18.8, with yearly changes in aDCSI score: 0.51 to 1.00, 1.01 to 2.00, and >2.00 vs <0.51, respectively; for trend <0.001).

CONCLUSION

Patients with T1DM are at an elevated risk of developing AC; this risk increases with T1DM progression. The T helper type 1/T helper type 2 hypothesis is an overly simplistic explanation for this association.

The flavonoid cyanidin blocks binding of the cytokine interleukin-17A to the IL-17RA subunit to alleviate inflammation in vivo

Cyanidin, a key flavonoid that is present in red berries and other fruits, attenuates the development of several diseases, including asthma, diabetes, atherosclerosis, and cancer, through its anti-inflammatory effects. We investigated the molecular basis of cyanidin action. Through a structure-based search for small molecules that inhibit signaling by the proinflammatory cytokine interleukin-17A (IL-17A), we found that cyanidin specifically recognizes an IL-17A binding site in the IL-17A receptor subunit (IL-17RA) and inhibits the IL-17A/IL-17RA interaction. Experiments with mice demonstrated that cyanidin inhibited IL-17A-induced skin hyperplasia, attenuated inflammation induced by IL-17-producing T helper 17 (TH17) cells (but not that induced by TH1 or TH2 cells), and alleviated airway hyperreactivity in models of steroid-resistant and severe asthma. Our findings uncover a previously uncharacterized molecular mechanism of action of cyanidin, which may inform its further development into an effective small-molecule drug for the treatment of IL-17A-dependent inflammatory diseases and cancer.

Characterization of IL-17AA and IL-17FF in rheumatoid arthritis and multiple sclerosis

Aim: IL-17 is thought to play a prominent role in immune disorders. Sensitive and specific IL-17AA and IL-17FF assays were developed and used to determine levels in serum and cerebrospinal fluid (CSF) from patients with rheumatoid arthritis and relapsing remitting multiple sclerosis (RRMS). Results: Qualified assays detected IL-17AA and IL-17FF in healthy and disease samples. Serum IL-17AA was significantly higher in rheumatoid arthritis and RRMS as compared with normal healthy subjects. IL-17AA was also elevated in RRMS CSF as compared with normal healthy subjects; although correlation was observed between serum levels of the two isoforms, no correlation was detected between serum and CSF levels. Conclusion: Reliable determination of IL-17 isoforms in the systemic and CNS compartments sheds light on the involvement of IL-17AA and IL-17FF in autoimmunity.

Blockage of Eosinopoiesis by IL-17A Is Prevented by Cytokine and Lipid Mediators of Allergic Inflammation

Interleukin- (IL-) 17A, a pleiotropic mediator of inflammation and autoimmunity, potently stimulates bone-marrow neutrophil production. To explore IL-17A effects on eosinopoiesis, we cultured bone-marrow from wild-type mice, or mutants lacking inducible nitric oxide synthase (iNOS−/−), CD95 (lpr), IL-17RA, or IL-4, with IL-5, alone or associated with IL-17A. Synergisms between IL-17A-activated, NO-dependent, and NO-independent mechanisms and antagonisms between IL-17A and proallergic factors were further examined. While IL-17A (0.1–10 ng/mL) had no IL-5-independent effect on eosinopoiesis, it dose-dependently suppressed IL-5-induced eosinophil differentiation, by acting during the initial 24 hours. Its effectiveness was abolished by caspase inhibitor, zVAD-fmk. The effect of IL-17A (0.1–1 ng/mL) was sensitive to the iNOS-selective inhibitor aminoguanidine and undetectable in iNOS−/− bone-marrow. By contrast, a higher IL-17A concentration (10 ng/mL) retained significant suppressive effect in both conditions, unmasking a high-end iNOS-independent mechanism. Lower IL-17A concentrations synergized with NO donor nitroprusside. Eosinopoiesis suppression by IL-17A was (a) undetectable in bone-marrow lacking IL-17RA or CD95 and (b) actively prevented by LTD4, LTC4, IL-13, and eotaxin. Sensitivity to IL-17A was increased in bone-marrow lacking IL-4; adding IL-4 to the cultures restored IL-5 responses to control levels. Therefore, effects of both IL-17A and proallergic factors are transduced by the iNOS-CD95 pathway in isolated bone-marrow.

The NLRP3 inflammasome: role in airway inflammation

Asthma is characterized by airway inflammation, airway hyperresponsiveness and airway remodelling. Uncontrolled airway inflammation or repeated asthma exacerbations can lead to airway remodelling, which cannot be reversed by current pharmacological treatment, and consequently lead to decline in lung function. Thus, it is critical to understand airway inflammation in asthma and infectious exacerbation. The inflammasome has emerged as playing a key role in innate immunity and inflammation. Upon ligand sensing, inflammasome components assemble and self-oligomerize, leading to caspase-1 activation and maturation of pro-IL-1β and pro-IL-18 into bioactive cytokines. These bioactive cytokines then play a pivotal role in the initiation and amplification of inflammatory processes. In addition to facilitating the proteolytic activation of IL-1β and IL-18, inflammasomes also participate in cell death through caspase-1-mediated pyroptosis. In this review, we describe the structure and function of the inflammasome and provide an overview of our current understanding of role of the inflammasome in airway inflammation. We focus on nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome as it is the best-characterized subtype shown expressed in airway and considered to play a key role in chronic airway diseases such as asthma.

Serum biomarkers in elderly asthma

OBJECTIVE

Asthma is usually misdiagnosed and under-treated in the elderly population, resulting in complications and increased severity to the patient. In this review, we describe some of the most important serum markers of asthma studied so far, reporting their outcomes and possible prediction of asthma in the elderly population.

METHODS

The PubMed electronic database was used to search for promising serum biomarkers of asthma studied in original articles published in peer-reviewed journals from 2000 to January 2013.

RESULTS

A total of 13 relevant serum biomarkers were selected, including IgE, CRP, high sensitive CRP, IL-6, IL-8, IL-17, TNF-α, neopterin, serum amyloid A, eosinophil cationic protein, leukolysin, YKL-40 and soluble CD86.

CONCLUSIONS

Although the major focus of treatment and research has been on allergic asthma, several forms of the disease are recognized, such as neutrophilic asthma, which is characteristic of older patients. Different phenotypes imply different treatments and so it becomes important to correctly determine which type of asthma the patient is suffering from. Serum markers capable of supporting a diagnosis of asthma are needed in order to counter mistreatment and misdiagnosis with other obstructive airways disease (OAD) in elderly patients. As convenient as serum markers may seem to be, a marker capable of accurately identifying asthma with sufficient specificity is yet to be found.

IL-17 family: cytokines, receptors and signaling

The interleukin 17 (IL-17) family, a subset of cytokines consisting of IL-17A-F, plays crucial roles in host defense against microbial organisms and in the development of inflammatory diseases. Although IL-17A is the signature cytokine produced by T helper 17 (Th17) cells, IL-17A and other IL-17 family cytokines have multiple sources ranging from immune cells to non-immune cells. The IL-17 family signals via their correspondent receptors and activates downstream pathways that include NFκB, MAPKs and C/EBPs to induce the expression of anti-microbial peptides, cytokines and chemokines. The proximal adaptor Act1 is a common mediator during the signaling of all IL-17 cytokines so far and is thus involved in IL-17 mediated host defense and IL-17-driven autoimmune conditions. This review will give an overview and recent updates on the IL-17 family, the activation and regulation of IL-17 signaling as well as diseases associated with this cytokine family.

Anti-inflammatory effect of qingpeng ointment in atopic dermatitis-like murine model

Qingpeng ointment (QP) is a Chinese medicine which has been used in treatment of atopic dermatitis (AD) in China. AD-like lesions were induced in BALB/c mice by repeated application of 2,4-dinitrofluorobenzene (DNFB) on shaved backs. The mice were then treated for 2 weeks with QP of different concentrations and Mometasone Furoate cream (MF), respectively. Macroscopic and microscopic changes of the skin lesions were observed after the treatment. The levels of serum immunoglobulin (Ig) E, tissue interferon (IFN)- γ , and interleukin (IL)-4 and IL-17A and the levels of involucrin, filaggrin, and kallikrein7 in epidermis were measured. The results show severe dermatitis with immune profiles similar to human acute AD. A significant infiltration of CD4(+) T and mast cells was observed in dermis of lesion but inhibited by QP after a 2-week treatment with it. The production of IgE, IL-4 and the mRNA expression of IL-17A were also suppressed, but the level of IFN- γ was increased. MF suppressed all production of these cytokines and IgE. Accordingly, the mechanism of QP on AD might correlate with its ability of modulating the immune dysfunctions rather than suppressing them. It had no effect on expressions of involucrin and filaggrin, except that its vehicle decreased the level of kallikrein7.

Interleukin-17 (IL-17) and IL-1 activate translation of overlapping sets of mRNAs, including that of the negative regulator of inflammation, MCPIP1

Changes in gene expression during inflammation are in part caused by post-transcriptional mechanisms. A transcriptome-wide screen for changes in ribosome occupancy indicated that the inflammatory cytokine IL-17 activates translation of a group of mRNAs that overlaps partially with those affected similarly by IL-1. Included are mRNAs of IκBζ and of MCPIP1, important regulators of the quality and course of immune and inflammatory responses. Evidence for increased ribosome association of these mRNAs was also obtained in LPS-activated RAW264.7 macrophages and human peripheral blood mononuclear cells. Like IL-1, IL-17 activated translation of IκBζ mRNA by counteracting the function of a translational silencing element in its 3'-UTR defined previously. Translational silencing of MCPIP1 mRNA in unstimulated cells resulted from the combined suppressive activities of its 5'-UTR, which contains upstream open reading frames, and of its 3'-UTR, which silences independently of the 5'-UTR. Only the silencing function of the 3'-UTR was counteracted by IL-17 as well as by IL-1. Translational silencing by the 3'-UTR was dependent on a putative stem-loop-forming region previously associated with rapid degradation of the mRNA. The results suggest that translational control exerted by IL-1 and IL-17 plays an important role in the coordination of an inflammatory reaction.

Mechanisms underlying helper T-cell plasticity: implications for immune-mediated disease

CD4 helper T cells are critical for proper immune cell homeostasis and host defense but are also major contributors to immune and inflammatory disease. Arising from a simple biphasic model of differentiation (ie, TH1 and TH2 cells). A bewildering number of fates seem possible for helper T cells. To what extent different helper cell subsets maintain their characteristic gene expression profiles or exhibit functional plasticity is a hotly debated topic. In this review we will discuss how the expression of "signature cytokines" and "master regulator" transcription factors do not neatly conform to a simple helper T-cell paradigm. Although this might seem confusing, the good news is that the newly recognized complexity fits better with our understanding of immunopathogenesis. Finally, we will discuss factors, including epigenetic regulation and metabolic alterations, that contribute to helper cell specificity and plasticity.

The pathologic and clinical intersection of atopic and autoimmune disease

Hypersensitivity reactions of the immune system have been broadly categorized into the atopic and autoimmune depending on whether the antigen triggering the reaction is endogenous (or self) or exogenous, the types of cellular and humoral components involved, and the clinical symptoms. Research into the pathophysiology of the resultant disease states has focused on a dichotomy between Th1 and Th2 T helper lymphocytes thought to govern autoimmune and atopic disease, respectively. Recent discoveries, however, have served to dispute this paradigm and have provided additional insight into the roles of Th17 cells, B-lymphocytes and T regulatory cells as well as the considerable communication and commonalities between the complex signaling pathways. Furthermore, clinical studies have served to challenge the idea that the presence of atopy and autoimmunity are mutually exclusive states. Finally, application of recent approaches to treatment-biologic targeted therapy in autoimmunity and induction of immune tolerance in atopic disease--to both disease states have shown mixed but promising results.

New era of biologic therapeutics in atopic dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a common inflammatory skin disease regulated by genetic and environmental factors. Both skin barrier defects and aberrant immune responses are believed to drive cutaneous inflammation in AD. Existing therapies rely largely on allergen avoidance, emollients and topical and systemic immune-suppressants, some with significant toxicity and transient efficacy; no specific targeted therapies are in clinical use today. As our specific understanding of the immune and molecular pathways that cause different subsets of AD increases, a variety of experimental agents, particularly biologic agents that target pathogenic molecules bring the promise of safe and effective therapeutics for long-term use.

AREAS COVERED

This paper discusses the molecular pathways characterizing AD, the contributions of barrier and immune abnormalities to its pathogenesis, and development of new treatments that target key molecules in these pathways. In this review, we will discuss a variety of biologic therapies that are in development or in clinical trials for AD, perhaps revolutionizing treatment of this disease.

EXPERT OPINION

Biologic agents in moderate to severe AD offer promise for controlling a disease that currently lacks good and safe therapeutics posing a large unmet need. Unfortunately, existing treatments for AD aim to decrease cutaneous inflammation, but are not specific for the pathways driving this disease. An increasing understanding of the immune mechanisms underlying AD brings the promise of narrow targeted therapies as has occurred for psoriasis, another inflammatory skin disease, for which specific biologic agents have been demonstrated to both control the disease and prevent occurrence of new skin lesions. Although no biologic is yet approved for AD, these are exciting times for active therapeutic development in AD that might lead to revolutionary therapeutics for this disease.

TH17 and TH22 cells: a confusion of antimicrobial response with tissue inflammation versus protection

Substantial progress in understanding mechanisms of immune regulation in allergy, asthma, autoimmune diseases, tumors, organ transplantation, chronic infections, and pregnancy is in an exciting developmental phase that might lead to a variety of targeted therapeutic approaches. Recent progress in the interaction between immune/inflammatory cell subsets through cytokines, particularly the extension of the knowledge on reciprocal regulation and counterbalance between subsets of T(H)1, T(H)2, T(H)9, T(H)17, T(H)22, T follicular helper cells and different subsets of regulatory T cells, as well as corresponding and co-orchestrating B-cell, natural killer cell, dendritic cell, and innate lymphoid cell subsets, offers new possibilities for immune intervention. Studies on new subsets confirm the important role of T cells in the instruction of tissue cells and also demonstrate the important role of feedback regulation for the polarization toward distinct T-cell subsets. T(H)17 and T(H)22 cells are 2 emerging T(H) cell subsets that link the immune response to tissue inflammation; IL-17A and IL-17F and IL-22 are their respective prototype cytokines. Although both cytokines play roles in immune defense to extracellular bacteria, IL-17 augments inflammation, whereas IL-22 plays a tissue-protective role. This review focuses on current knowledge on T(H)17 and T(H)22 cells and their role in inflammation, with special focus on the mechanisms of their generation and driving and effector cytokines, as well as their role in host defense, autoimmunity, and allergic diseases.

Molecular mechanisms of mucocutaneous immunity against Candida and Staphylococcus species

Signal transducer and activator of transcription (STAT) proteins are key components of the innate and adaptive immune responses to pathogenic microorganisms. Recent research on primary immunodeficiency disorders and the identification of patients carrying germline mutations in STAT1, STAT3, and STAT5B have highlighted the role of human STATs in host defense against various viruses, bacteria, and fungi. Mutations in STAT1 and STAT3 disrupt various cytokine pathways that control mucocutaneous immunity against Candida species, especially Candida albicans, and Staphylococcus species, especially Staphylococcus aureus. Here we consider inborn errors of immunity arising from mutations in either STAT1 or STAT3 that affect mucocutaneous immunity to Candida and Staphylococcus species.

TH17 Cells in Autoimmunity and Immunodeficiency: Protective or Pathogenic?

In 2005 a newly discovered T helper cell subset that secreted interleukin (IL)-17 became the center of attention in immunology. Initial studies painted Th17 cells as the culprit for destruction in many different autoimmune and auto-inflammatory diseases. Subsequently, the discovery of patients with primary immunodeficiencies in the IL-17 pathway taught us that Th17 cells have a critical role in defense against certain fungal and bacterial infections. Moreover, the paradoxical exacerbation of Crohn's disease in the clinical trials of a Secukinumab (AIN457), a fully human neutralizing antibody to IL-17A, has cast into doubt a universal pro-inflammatory and harmful role for Th17 cells. Evidence now suggests that depending on the environment Th17 cells can alter their differentiation program, ultimately giving rise to either protective or pro-inflammatory cells. In this review we will summarize the evidence from patients with immunodeficiencies, autoimmune, or auto-inflammatory diseases that teaches us how the pro-inflammatory versus protective function of Th17 cells varies within the context of different human diseases.