Aberrant expression of regulatory cytokine IL-35 and pattern recognition receptor NOD2 in patients with allergic asthma

Current Insight into the Role of IL-35 and Its Potential Involvement in the Pathogenesis and Therapy of Atopic Dermatitis

Interleukin 35 (IL-35), a new member of the IL-12 family of heterodimeric cytokines, could induce two different types of regulatory cells including regulatory T and B cells such as IL-35-induced regulatory T cells and IL-10-producing regulatory B cells (IL-10+Bregs), and IL-35-producing regulatory B cells (IL-35+Bregs). These cells appear to play an important role in modulating the immune system in numerous diseases. Several findings suggested that the expression of IL-35 is dysregulated in many autoimmune, inflammatory, and allergic diseases. Due to the functions of IL-35, it seems that this cytokine may act as an efficient therapeutic strategy for numerous conditions including atopic dermatitis (AD). We aimed to provide a comprehensive overview of the role of IL-35 in modulating the immune system. Additionally, we highlight IL-35 as a specific immunological target, discuss its possible involvement in the pathogenesis of AD, and hypothesize that IL-35 may become a novel target for the treatment of AD. However, further studies are required to evaluate this hypothesis.

NOD-like receptors in asthma

Asthma is an extremely prevalent chronic inflammatory disease of the airway where innate and adaptive immune systems participate collectively with epithelial and other structural cells to cause airway hyperresponsiveness, mucus overproduction, airway narrowing, and remodeling. The nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) are a family of intracellular innate immune sensors that detect microbe-associated molecular patterns and damage-associated molecular patterns, well-recognized for their central roles in the maintenance of tissue homeostasis and host defense against bacteria, viruses and fungi. In recent times, NLRs have been increasingly acknowledged as much more than innate sensors and have emerged also as relevant players in diseases classically defined by their adaptive immune responses such as asthma. In this review article, we discuss the current knowledge and recent developments about NLR expression, activation and function in relation to asthma and examine the potential interventions in NLR signaling as asthma immunomodulatory therapies.

Allergic Aspects of IgG4-Related Disease: Implications for Pathogenesis and Therapy

IgG4-related disease (IgG4-RD) is a rare systemic fibroinflammatory disease frequently associated with allergy. The pathogenesis of IgG4-RD is poorly understood, and effective therapies are limited. However, IgG4-RD appears to involve some of the same pathogenic mechanisms observed in allergic disease, such as T helper 2 (Th2) and regulatory T cell (Treg) activation, IgG4 and IgE hypersecretion, and blood/tissue eosinophilia. In addition, IgG4-RD tissue fibrosis appears to involve activation of basophils and mast cells and their release of alarmins and cytokines. In this article, we review allergy-like features of IgG4-RD and highlight targeted therapies for allergy that have potential in treating patients with IgG4-RD.

Behind the scenes with basophils: an emerging therapeutic target

Though basophils were originally viewed as redundant blood ‘mast cells’, the implementation of flow cytometry has established basophils as unique leukocytes with critical immunomodulatory functions. Basophils play an active role in allergic inflammation, autoimmunity, and hematological malignancies. They are distinguishable from other leukocytes by their characteristic metachromatic deep-purple cytoplasmic, round granules. Mature basophils are phenotypically characterized by surface expression of IL-3Rα (CD123); IL-3 drives basophil differentiation, degranulation, and synthesis of inflammatory mediators including type 2 cytokines. Basophil degranulation is the predominant source of histamine in peripheral blood, promoting allergic responses. Basophils serve as a bridge between innate and adaptive immunity by secreting IL-4 which supports eosinophil migration, monocyte differentiation into macrophages, B-cell activation, and CD4 T-cell differentiation into Th2 cells. Further, basophilia is a key phenomenon in myeloid neoplasms, especially chronic myeloid leukemia (CML) for which it is a diagnostic criterion. Increased circulating basophils, often with aberrant immunophenotype, have been detected in patients with CML and other myeloproliferative neoplasms (MPNs). The significance of basophils’ immunoregulatory functions in malignant and non-malignant diseases is an active area of research. Ongoing and future research can inform the development of immunotherapies that target basophils to impact allergic, autoimmune, and malignant disease states. This review article aims to provide an overview of basophil biology, identification strategies, and roles and dysregulation in diseases.

Elevated levels of interleukin-35 and interleukin-37 in adult patients with obstructive sleep apnea

Background

Systemic inflammation has a critical role in the pathogenesis of obstructive sleep apnea (OSA). Interleukin (IL)‐35 and IL‐37 have been identified as novel immune‐modulating cytokines with anti‐inflammatory activities in numerous types of inflammatory disease. The present study aimed to examine the serum levels of IL‐35 and IL‐37 in patients with OSA, and to investigate their associations with the severity of OSA.

Methods

A total of 97 patients, including 67 cases of OSA and 30 age‐ and gender‐matched healthy control subjects, were enrolled in the present study. All subjects were evaluated by overnight polysomnography. Serum IL‐35, IL‐37, and pro‐inflammatory cytokine IL‐1β levels were examined by ELISA.

Results

Compared with those in the control subjects, serum IL‐35, IL‐37, and IL‐1β levels were significantly elevated in patients with mild, moderate, or severe OSA. Furthermore, a severity‐dependent increase in serum IL‐35 and IL‐37 levels was observed in patients with OSA. IL‐35 and IL‐37 levels were positively correlated with the apnea‐hypopnea index (r = 0.742 and 0.578, respectively; both p < 0.001), while they were negatively correlated with the mean oxygen saturation (r = −0.461 and −0.339, respectively; both p < 0.001) and lowest oxyhaemoglobin saturation (r = −0.616 and −0.463, respectively; both p < 0.001) in patients with OSA. In addition, a positive correlation was observed between IL‐35 or IL‐37 and IL‐1β levels (all p < 0.001).

Conclusion

The serum levels of IL‐35 and IL‐37 were significantly increased in patients with OSA and associated with the severity of OSA, implying that IL‐35 and IL‐37 may have a protective role in OSA by counteracting inflammatory responses.

IL-35 and IL-37 are negatively correlated with high IgE production among children with asthma in Saudi Arabia

BACKGROUND

Asthma is one of the most prevalent inflammatory disorders among children in Saudi Arabia.

OBJECTIVE

This study aimed to determine the correlation between the serum levels of vitamin D, immunoglobulin E (IgE), and cytokine (interferon-gamma (IFN-γ), interleukin (IL)-1β, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37) in relation to the severity of disease in patients with asthma.

METHODS

This case-control study was carried out at King Abdullah Specialist Children's Hospital, Saudi Arabia, and included 48 patients with asthma and 47 matched controls, aged 6-14 years. A validated questionnaire was administered to the participants, after which each patient with asthma underwent pulmonary function tests. The serum levels of vitamin D, IgE, IFN-γ, IL-1β, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37 of each participant were also measured.

RESULTS

Patients with asthma demonstrated significantly higher IgE and cytokine (IL-1β, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37) levels compared to the control group (p value < .001). The levels of IL-1β, IL-4, IL-10, and IL-13 were consistently positively correlated with the serum levels of IgE among patients with asthma. However, the IgE levels in patients with asthma were consistently negatively correlated with IL-35 and IL-37.

CONCLUSIONS

We found significantly higher levels of eosinophils, IgE, IL-1β, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37 in patients with asthma compared to the controls, but no relationship between vitamin D and asthma.

Immunological Roles of NLR in Allergic Diseases and Its Underlying Mechanisms

Our understanding on the immunological roles of pathogen recognition in innate immunity has vastly increased over the past 20 years. Nucleotide-binding oligomerization domain (NOD)-like receptors (NLR) are cytosolic pattern recognition receptors (PRR) that are responsible for sensing microbial motifs and endogenous damage signals in mammalian cytosol for immune surveillance and host defense. The accumulating discoveries on these NLR sensors in allergic diseases suggest that the pathogenesis of allergic diseases may not be confined to the adaptive immune response. Therapy targeting NLR in murine models also shields light on its potential in the treatment of allergies in man. In this review, we herein summarize the recent understanding of the role of NLR sensors and their molecular mechanisms involved in allergic inflammation, including atopic dermatitis and allergic asthma.

Interleukin-35 promotes the differentiation of regulatory T cells and suppresses Th2 response in IgG4-related type 1 autoimmune pancreatitis

BACKGROUND

IgG4-related disease (IgG4-RD) is a systemic inflammatory disease, which includes type 1 autoimmune pancreatitis (AIP). Interleukin-35 (IL-35) exhibits immunosuppressive effects in several autoimmune diseases. However, the expression of IL-35 had not been reported so far in type 1 AIP. We evaluated the association between IL-35 and several cytokines, which mediate the function of Tregs in type 1 AIP.

METHODS

Plasma was collected from patients with type 1 AIP, alcoholic chronic pancreatitis (ACP), and healthy controls (HC) and assayed for cytokine expression. Total mRNA separated from peripheral blood was isolated from naïve Tregs (nTregs) and effector Tregs (eTregs). EBI3 and IL-12p35 gene expressions were tested in these cells by quantitative PCR. In addition, expression of IL-35 subunits in the pancreatic tissues of patients with type 1 AIP and ACP was analyzed by immunohistochemistry.

RESULTS

IL-35 was significantly elevated in type 1 AIP (n = 32) plasma compared with ACP (n = 16) and HC (n = 22), but IL-27 was not. We also detected many cells expressing both EBI3 and IL-12p35 in type 1 AIP tissues. Moreover, in peripheral blood lymphocyte, the percentage of nTregs and eTregs of CD4⁺ T cells in patients with type 1 AIP (n = 14) compared with HC (n = 15) was significantly decreased and increased, respectively. There were no significant differences of gene expression in patients with type 1 AIP and HC.

CONCLUSIONS

This study identified elevated expression of plasma IL-35 and tissue IL-35 subunits in patients with type 1 AIP. This might lead to inflammation suppression via activated eTregs. IL-35 might be associated with this anti-inflammatory role, especially against the Th2 response through several cytokines and the differentiation of Tregs in type 1 AIP.

Quantification of Early-Stage Myeloid-Derived Suppressor Cells in Cancer Requires Excluding Basophils

Myeloid derived suppressor cells (MDSC) are a heterogeneous group of immature cells that accumulate in the peripheral blood and tumor microenvironment and are barriers to cancer therapy. MDSCs serve as prognostic biomarkers and are targets for therapy. On the basis of surface markers, three subsets of MDSCs have been defined in humans: granulocytic, monocytic, and early stage (e-MDSC). The markers attributed to e-MDSCs overlap with those of basophils, which are rare circulating myeloid cells with unrecognized roles in cancer. Thus, we asked whether e-MDSCs in circulation and the tumor microenvironment include basophils. On average, 58% of cells with e-MDSC surface markers in blood and 36% in ascites from patients with ovarian cancer were basophils based on CD123high expression and cytology, whereas cells with immature features were rare. Circulating and ascites basophils did not suppress proliferation of stimulated T cells, a key feature of MDSCs. Increased accumulation of basophils and basogranulin, a marker of basophil degranulation, were observed in ascites compared to serum in patients with newly diagnosed ovarian cancer. Basophils recruited to the tumor microenvironment may exacerbate fluid accumulation by their release of proinflammatory granular constituents that promote vascular leakage. No significant correlation was observed between peripheral basophil counts and survival in patients with ovarian cancer. Our results suggest that studies in which e-MDSCs were defined solely by surface markers should be reevaluated to exclude basophils. Both immaturity and suppression are criteria to define e-MDSCs in future studies.

Different expression levels of interleukin-35 in asthma phenotypes

Background

Interleukin (IL)-35 is a newly discovered inhibitory cytokine which is produced by regulatory B and T lymphocytes and belongs to the IL-12 family. It plays a suppressive role in human inflammatory diseases; however, its role in asthma phenotypes is unclear. Our study focuses on the sputum IL-35 level in patients and investigates different airway inflammation capacities of sputum IL-35 in patients with different asthma phenotypes.

Objective

We aimed to determine the sputum IL-35 levels in asthmatic patients with clinical remission phenotypes and control subjects and to investigate possible correlations among lung function, age, sex, fractional exhaled nitric oxide (FeNO), and smoking history in these phenotypes.

Methods

Sputum samples were collected from patients with clinical asthma remission (n = 89, 37 males, age 52.24 ± 13.32 years) and a healthy control group (n = 19, 9 males, age 44.58 ± 16.3 years). All subjects underwent sputum induction. Induced sputum was assessed for inflammatory cell count, and sputum levels of IL-35 and other cytokines were measured by ELISA and Cytometric Bead Array, respectively.

Results

Sputum IL-35 (median (q1, q3)) levels showed no significant difference between asthma patients (4.89 ng/mL (2.97, 22.75)) and healthy controls (6.01 ng/mL (4.09, 30.47)). However, the sputum IL-35 level was significantly reduced in patients with eosinophilic asthma (EA) (3.95 ng/mL (2.80, 11.00)) compared to patients with neutrophilic asthma (NA) (40.59 ng/mL (20.59, 65.06), p = 0.002), paucigranulocytic asthma (PA) (6.25 ng/mL (3.10, 24.60), p = 0.012), and mixed granulocytic asthma (MA) (22.54 ng/mL (2.58, 52.45), p = 0.026). IL-35 levels in sputum showed a positive correlation with sputum neutrophil cells and a negative correlation with FeNO, FEV1% predicted, and FVC predicted. Furthermore, sputum IL-35 had a significant positive association with Th1-related factors and a negative correlation with Th2-related factors.

Conclusions

Sputum IL-35 is likely involved in different pathophysiological mechanisms of NA and EA and exerts different effects in asthma phenotypes.

Leptin: an unappreciated key player in SLE

Leptin is the forerunner of the adipokine superfamily and plays a key role in regulating energy expenditure and neuroendocrine function. Researches into leptin put emphasize not only on the metabolic role but also its immunoregulatory effect on immune response through immunocyte activation and cytokine secretion. Leptin acts on receptors that are widespread throughout the body and that are expressed across many tissue types. As a consequence, the abnormal expression of leptin has been found to correlate with a number of diseases, including cancers, autoimmune diseases, and cardiovascular diseases. The significance of leptin in the development of autoimmune diseases is becoming increasingly prominent. Systemic lupus erythematosus (SLE) is a severe atypical autoimmune disease that causes damage to multiple organ systems. It is characterised by the following: impaired clearance of apoptotic cells, loss of tolerance to self-antigens, aberrant activation of T cells and B cells, and chronic inflammation. The heightened immunocyte response in SLE means that these physiological systems are particularly vulnerable to regulation by leptin in addition to being of great significance to the research field. Our current review provides insight into the regulatory roles that leptin plays on immune effector cells in SLE.

Gene Variants, mRNA and NOD1/2 Protein Levels in Tunisian Childhood Asthma

INTRODUCTION

Asthma is a common respiratory childhood disease that results from an interaction between genetic, environmental and immunologic factors. The implication of nucleotide-binding and oligomerization domain 1 and 2 (NOD1/CARD4, NOD2/CARD15) was highlighted in many inflammatory diseases.

METHODS

In this case-control study, we analyzed the association of three NOD2 polymorphisms and one NOD1 variant, in 338 Tunisian asthmatic children and 425 healthy Controls, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. We also assessed NOD1 and NOD2 mRNA and protein levels by qRT-PCR and ELISA techniques.

RESULTS

The homozygous AA genotype of rs2075820 was a risk factor for asthma (OR 2.39). The influence of the E266K variant in the presence of the heterozygous AG genotype was higher in male than female groups. The homozygous AA genotype was a risk factor associated with asthma, for patients aged between 6 and 18 years OR 2.39, IC95% (1.04-5.49) p < 0.01. The mRNA expression of NOD1, but not NOD2, was enhanced in asthma patients compared to Controls. We noted a significant difference between asthmatics and healthy controls in NOD1 protein expression (asthma patients : 31.18 ± 10.9 pg/ml, Controls: 20.10 ± 2.58 pg/ml; p < 0.001).

CONCLUSIONS

The NOD1 rs2075820 variant was associated with a higher childhood asthma risk and the NOD1 expression at mRNA and protein levels was significantly increased in asthma patients.

Changes and correlations of serum interleukins, adhesion molecules and soluble E-selectin in children with allergic rhinitis and asthma

OBJECTIVE

To observe the changes and correlations of serum interleukins (ILs), adhesion molecules and soluble E-selectin (sE-selectin) in children with allergic rhinitis, asthma and both diseases.

METHODS

A total of 45 children with allergic rhinitis, 40 with asthma and 45 with allergic rhinitis complicated with asthma treated from September 2016 to January 2018 were selected. Meanwhile, 30 healthy subjects who received physical examinations were included as a control group. The levels of serum IL-4, IL-5, IL-10, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular adhesion molecule-1 (sVCAM-1), and sE-selectin were detected by double-antibody sandwich ELISA, and their correlations were subjected to Spearman's correlation analysis.

RESULTS

The serum IL levels of allergic rhinitis, asthma and complication groups were significantly higher than those of control group (P<0.01), and the levels of complication group significantly exceeded those of asthma group (P<0.05). The serum levels of IL-5 and IL-10 in complication group significantly exceeded those of allergic rhinitis group (P<0.05). Compared with control group, serum sICAM-1, sVCAM-1, and sE-selectin levels significantly increased in other three groups (P<0.01). Such levels of complication group were significantly higher than those of allergic rhinitis and asthma groups (P<0.05). Serum IL-10 level was positively correlated with that of IL-4 (r=0.965, P<0.05), and sE-selectin level was positively correlated with those of sICAM-1 and sVCAM-1 (r=0.915, P<0.01; r=0.892, P<0.01).

CONCLUSION

Serum IL-4, IL-5, IL-10, adhesion molecules and sE-selectin are all involved in the pathogenesis of allergic rhinitis and asthma, which can be used to evaluate the degrees of respiratory allergic diseases.

Clinical effects of tanshinone IIA sodium sulfonate combined with trimetazidine and levocarnitine in the treatment of AVMC and its effects on serum TNF-α, IL-18 and IL-35

Clinical effects of tanshinone IIA sodium sulfonate combined with trimetazidine and levocarnitine in the treatment of acute viral myocarditis (AVMC) were investigated. Eighty-six patients with AVMC treated in Dongying City People's Hospital from August 2016 to July 2017 were selected and randomly divided into control group (n=43) and observation group (n=43). Patients in control group were treated with tanshinone IIA sodium sulfonate, while those in observation group were treated with trimetazidine and levocarnitine. The curative effect and improvement in clinical symptoms were compared between the two groups of patients, and enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of heart-type fatty acid-binding protein (H-FABP), creatine kinase-MB (CK-MB) and cardiac troponin I (cTnI) in patients after treatment. Besides, the changes in levels of serum tumor necrosis factor-α (TNF-α), interleukin (IL)-18 and IL-35 were detected via ELISA. The total effective rate of treatment in observation group was significantly higher than that in control group (p<0.05). The improvement in clinical symptoms in observation group was significantly superior to that in control group (p<0.05). After treatment, levels of H-FABP, CK-MB and cTnI in observation group were obviously lower than those in control group (p<0.05). At 3, 5 and 7 days after treatment, the levels of TNF-α and IL-18 in both groups of patients were decreased compared with those before treatment, but the level of IL-35 was increased compared with that before treatment, and changes in observation group were more significant than those in control group (p<0.05). Tanshinone IIA sodium sulfonate combined with trimetazidine and levocarnitine has definite curative effects in the treatment of patients with AVMC, which can alleviate myocardial injury with higher safety, and effectively mitigate the inflammatory response in patients, so it is of great clinical significance.

Diminished circulating concentration of interleukin-35 in Helicobacter pylori-infected patients with peptic ulcer: Its association with FOXP3 gene polymorphism, bacterial virulence factor CagA, and gender of patients

BACKGROUND

IL-35 modulates immune and inflammatory responses during infections. Here, we investigated IL-35 levels and a single nucleotide polymorphism, rs3761548, in FOXP3 gene in Helicobacter pylori-infected patients with peptic ulcer (PU), to clarify possible associations.

MATERIALS AND METHODS

This study includes 100 H. pylori-infected PU patients, 100 H. pylori-infected asymptomatic subjects (AS), and 100 noninfected healthy subjects (NHSs). Serum IL-35 levels and the genotyping were determined using ELISA and RFLP-PCR methods, respectively.

RESULTS

In PU patients, the IL-35 levels were lower than AS and NHS groups (P < .001). The IL-35 levels in CagA⁺ H. pylori-infected participants from PU and AS groups were lower than individuals infected with CagA^- strains (P < .02 and P < .04, respectively). Women had higher IL-35 levels than men among PU, AS, and NHS groups (P < .0001). In PU patients, AA genotype and A allele at rs3761548 were more frequent than total healthy subjects (AS + NHS groups) and associated with an increased PU risk (AA genotype: OR = 5.51, P < .0001; A allele: OR = 3.857, P < .002). In PU and AS groups, IL-35 levels were lower in subjects displaying AA genotype or A allele than subjects displaying CC genotype or C allele, respectively (P < .0001 and P < .03 for PU patients; P < .001 and P < .02 for AS group, respectively).

CONCLUSIONS

Decreased IL-35 levels could be involved in PU development in H. pylori-infected individuals. IL-35 levels are affected by CagA status of H. pylori, participants gender, and genetic variations at rs3761548. The AA genotype and A allele at rs3761548 could represent a risk factor for PU development.

NOD2 expression, DNA damage and oxido-inflammatory status in atopic bronchial asthma: Exploring their nexus to disease severity

BACKGROUND

Allergic asthma is a chronically relapsing inflammatory airway disease with a complex pathophysiology.

AIM

This study was undertaken to investigate the potential contribution of NOD2 signaling, proinflammatory cytokines, chitotriosidase (CHIT1) activity, oxidative stress and DNA damage to atopic asthma pathogenesis, as well as to explore their possible role as surrogate noninvasive biomarkers for monitoring asthma severity.

METHODS

Sixty patients with atopic bronchial asthma who were divided according to asthma severity into 40 mild-moderate, 20 severe atopic asthmatics, in addition to thirty age-matched healthy controls were enrolled in this study. NOD2 expression in PBMCs was assessed by quantitative real-time RT-PCR. DNA damage indices were assessed by alkaline comet assay. Serum IgE, IL-17, IL-8 and 3-Nitrotyrosine levels were estimated by ELISA. Serum CHIT1and GST activities, as well as MDA levels, were measured.

RESULTS

NOD2 mRNA relative expression levels were significantly decreased in atopic asthmatic cases relative to controls with lower values among severe atopic asthmatics. On the other hand, IL-17 and IL-8 serum levels, CHIT1 activity, DNA damage indices and oxidative stress markers were significantly increased in atopic asthmatic cases relative to controls with higher values among severe atopic asthmatics. The change in these parameters correlated significantly with the degree of decline in lung function.

CONCLUSION

The interplay between NOD2 signaling, proinflammatory cytokines, CHIT1 activity, heightened oxidative stress and DNA damage orchestrates allergic airway inflammation and thus contributing to the pathogenesis of atopic asthma. These parameters qualified for measurement as part of new noninvasive biomarker panels for monitoring asthma severity.

Lower level of IL‑35 and its reduced inhibition in Th17 cells in patients with bone marrow mononuclear cells Coombs test‑positive hemocytopenia

Interleukin (IL)-35 is the latest member of IL-12 family, which plays an important role in other autoimmune diseases. Bone marrow mononuclear cells Coombs test-positive hemocytopenia, also termed immunorelated hemocytopenia (IRH) is a type of autoimmune-associated diseases. The present study investigated the relationship of IL-35 in patients with IRH. A total of 43 patients with IRH and 19 normal controls were enrolled in the current study. Serum levels of IL-35 and IL-17 in peripheral blood were evaluated by ELISA. Regulatory T cells (Tregs) level was detected by flow cytometry and IL-35 subunits mRNA in Treg was determined using reverse transcription-quantitative polymerase chain reaction: Epstein-Barr virus induced 3 (EBI3) and IL-12α chain p35. Effect of IL-35 on T helper 17 cells (Th17) cells was determined by mix-culture of IL-35 with CD4⁺ T lymphocytes. Serum level of IL-35 was decreased in untreated patients with IRH compared with remission patients (P<0.01) and was significantly associated with clinical indexes. Frequency of IL-35 produced Tregs was lower and IL-35 subunits mRNA in CD4⁺CD25⁺ Tregs were decreased in patients with IRH compared with health controls (P<0.01). Serum level of IL-17 was increased in patients with IRH (P<0.01) and there was a negative correlation between IL-35 and IL-17 (r=−0.553; P<0.01). The production of Th17 cells and IL-17A mRNA expression were reduced (P<0.05) after mix-culture of CD4⁺ T lymphocytes with IL-35 compared with mix-culture of CD4⁺ T lymphocytes without IL-35. In conclusion, the present study revealed that IL-35 may be a monitoring indicator of IRH occurrence and progression. IL-35 level was lower and the inhibition on Th17 cells was reduced in the patients with IRH.

Cutaneous Nod2 Expression Regulates the Skin Microbiome and Wound Healing in a Murine Model

The skin microbiome exists in dynamic equilibrium with the host, but when the skin is compromised, bacteria can colonize the wound and impair wound healing. Thus, the interplay between normal skin microbial interactions versus pathogenic microbial interactions in wound repair is important. Bacteria are recognized by innate host pattern recognition receptors, and we previously showed an important role for the pattern recognition receptor NOD2 in skin wound repair. NOD2 is implicated in changes in the composition of the intestinal microbiota in Crohn’s disease, but its role on skin microbiota is unknown. Nod2-deficient (Nod2^–/–) mice had an inherently altered skin microbiome compared with wild-type controls. Furthermore, we found that Nod2^–/– skin microbiome dominated and caused impaired healing, shown in cross-fostering experiments of wild-type pups with Nod2^–/– pups, which then acquired altered cutaneous bacteria and delayed healing. High-throughput sequencing and quantitative real-time PCR showed a significant compositional shift, specifically in the genus Pseudomonas in Nod2^–/– mice. To confirm whether Pseudomonas species directly impair wound healing, wild-type mice were infected with Pseudomonas aeruginosa biofilms and, akin to Nod2^–/– mice, were found to exhibit a significant delay in wound repair. Collectively, these studies show the importance of the microbial communities in skin wound healing outcome.

Role of Anti-inflammatory Cytokines IL-35 and IL-37 in Asthma

Asthma is a chronic airway inflammation that is characterized by intense eosinophil infiltrates, mucus hypersecretion, airway remodeling, and airway hyperresponsiveness. Interleukin (IL)-35 and IL-37 are two cytokines with anti-inflammatory effects found in immune response. Recent findings suggested that expressions of IL-35 and IL-37 are abnormal in asthma. Functional analysis further confirmed the important roles of them in the pathogenesis of asthma. The present study reviewed the updated evidence indicating the roles of IL-35 and IL-37 in asthma. Hopefully, the information obtained may lead to a better understanding of the pathogenesis of the disease.

Interluekin-35 in Asthma and Its Potential as an Effective Therapeutic Agent

Interleukin- (IL-) 35 is a member of the IL-12 cytokine family and a heterodimeric protein formed by Epstein-Barr-induced gene 3 (EBI3) and IL-12p35. Emerging evidence shows that IL-35 is a key player in the regulation of cellular communication, differentiation, and inflammation. Altered IL-35 expression has been found in disease conditions such as cancer, rheumatoid arthritis, and, more recently, asthma. In cancer, IL-35 is involved in the regulation of tumorigenesis, cancer progression, and metastasis. In rheumatoid arthritis, IL-35 acts as a negative regulator of inflammation. Similarly, IL-35 also appears to suppress allergic inflammation in asthma. In an in vivo murine model of asthma, transfer of adenovirus-mediated IL-35 markedly reduced the degree of airway hyperresponsiveness (AHR) and inflammatory cell infiltration. Many studies have shown the involvement of IL-35 in a number of aspects of allergic inflammation, such as eosinophil and neutrophil recruitment as well as inhibition of inflammatory mediators of the Th2 subtype. However, the exact molecular mechanisms underlying the role of IL-35 in human asthma have yet to be fully elucidated. This review describes the current evidence regarding the role of IL-35 in the pathophysiology of asthma and evaluates the potential of IL-35 as a biomarker for airway inflammation and a therapeutic target for the treatment of asthma.

A Systematic Analysis of Treatment and Outcomes of NOD2-Associated Autoinflammatory Disease

OBJECTIVES

Yao syndrome, formerly named NOD2-associated autoinflammatory disease, is a periodic disease characterized by fever, dermatitis, polyarthritis/leg swelling, and gastrointestinal and sicca-like symptoms associated with specific NOD2 sequence variants. Our aim was to evaluate the treatment and outcomes of the disease.

METHODS

A total of 52 adult patients with autoinflammatory disease phenotype were diagnosed with Yao syndrome and enrolled at the Cleveland Clinic between November 2009 and May 2015. All patients were genotyped for the NOD2 variants, and systematically studied for treatment outcomes.

RESULTS

Among the 52 Yao syndrome patients, all were white, and 72% were women. The mean age at diagnosis was 38.0 ± 12.0 years, and the disease duration was 8.8 ± 5.8 years. In the multi-organ disease, more common and typical manifestations were recurrent dermatitis and inflammatory arthritis with or without distal leg swelling besides recurrent fever. It was genotypically associated with the NOD2 IVS8⁺¹⁵⁸ or R702W. Therapeutically, glucocorticoids markedly decreased the disease severity and duration of flares in 19 patients (36.6%), sulfasalazine treatment achieved a significant symptomatic improvement in 22 (42%) patients, and 3 patients received canakinumab or tocilizumab with benefits. Prognostically, 13% of the 52 patients had somewhat physical impairment, and there was no mortality during the follow-up. Associated comorbidities were fibromyalgia, asthma, renal stones, and ventricular hypertrophy.

CONCLUSIONS

As a systemic disease, Yao syndrome uncommonly affects the solid internal organs, but it can be complicated with chronic pain syndrome and even disability. Glucocorticoids or sulfasalazine may be considered as the first-line treatment option, and interleukin (IL)-1/IL-6 inhibitors may be tried for refractory cases. The potential associations between certain comorbidities and Yao syndrome deserve further study.

Aberrant Expression of Novel Cytokine IL-38 and Regulatory T Lymphocytes in Childhood Asthma

We investigated the expression of novel anti-inflammatory interleukin (IL)-38 and regulatory T (Treg) lymphocytes in childhood asthma patients. The protein and mRNA expression level of IL-38, periostin, peripheral CD4⁺CD25⁺CD134⁺ T lymphocytes as well as CD4⁺CD25(high)FoxP3⁺ and CD4⁺CD25(high)CD127(-) Treg lymphocytes from 40 asthmatic patients and 20 normal control (NC) subjects were studied using ELISA, qPCR and flow cytometry. Serum and supernatant cytokines/chemokines were determined by multiplex assay. Serum IL-38, IL-5, IL-17, IL-6, interferon-γ, periostin, IL-1β and IL-13 concentrations were significantly higher in asthmatic patients with or without steroid treatment than those in controls (all p < 0.05). The percentages of both CD4⁺CD25(high)FoxP3⁺ and CD4⁺CD25(high)CD127(-) Treg lymphocytes were markedly decreased in asthmatic patients with and without steroid treatment than those in controls (all p < 0.05). The elevated IL-38 concentration negatively correlated with the percentage of Treg lymphocytes in asthmatic patients with high level (>40 ng/mL) of periostin (p < 0.05). Although the comparable mRNA levels of IL-38 and its receptor IL-36R were found between patients and controls, the mRNA level of IL-38 positively correlated with IL-36R and negatively correlated with IL-10 in all asthmatic patients (both p < 0.05). The percentage of CD4⁺CD25⁺CD134⁺ activated T lymphocytes was also significantly higher in asthmatic patients with steroid treatment than those in controls (p < 0.05). This cross-sectional study demonstrated that the overexpression of circulating IL-38 may play a role in the immunopathogenesis in asthma.

Gene Expression and Antiviral Activity of Interleukin-35 in Response to Influenza A Virus Infection

Interleukin-35 (IL-35) is a newly described member of the IL-12 family. It has been reported to inhibit inflammation and autoimmune inflammatory disease and can increase apoptotic sensitivity. Little is known about the role of IL-35 during viral infection. Herein, high levels of IL-35 were found in peripheral blood mononuclear cells and throat swabs from patients with seasonal influenza A virus (IAV) relative to healthy individuals. IAV infection of human lung epithelial and primary cells increased levels of IL-35 mRNA and protein. Further studies demonstrated that IAV-induced IL-35 transcription is regulated by NF-κB. IL-35 expression was significantly suppressed by selective inhibitors of cyclooxygenase-2 (COX-2) and inducible nitric-oxide synthase, indicating their involvement in IL-35 expression. Interestingly, IL-35 production may have suppressed IAV RNA replication and viral protein synthesis via induction of type I and III interferons (IFN), leading to activation of downstream IFN effectors, including double-stranded RNA-dependent protein kinase, 2',5'-oligoadenylate synthetase, and myxovirus resistance protein. IL-35 exhibited extensive antiviral activity against the hepatitis B virus, enterovirus 71, and vesicular stomatitis virus. Our results demonstrate that IL-35 is a novel IAV-inducible cytokine, and its production elicits antiviral activity.

Update on the role of alternatively activated macrophages in asthma

Lung macrophages link innate and adaptive immune responses during allergic airway inflammatory responses. Alveolar macrophages (AMs) and interstitial macrophages are two different phenotypes that differentially exert immunological function under physiological and pathological conditions. Exposure to pathogen induces polarization of AM cells into classically activated macrophages (M1 cells) and alternatively activated macrophages (M2 cells). M1 cells dominantly express proinflammatory cytokines such as TNF-α and IL-1 β and induce lung inflammation and tissue damage. M2 cells are further divided into M2a and M2c subsets. M2a cells dominantly produce allergic cytokines IL-4 and IL-13, but M2c cells dominantly produce anti-inflammatory cytokine IL-10. M2a and M2c cells are differently involved in initiation, inflammation resolution, and tissue remodeling in the different stages of asthma. Microenvironment dynamically influences polarization of AM cells. Cytokines, chemokines, and immune-regulatory cells interplay and affect the balance between the polarization of M1 and M2 cells, subsequently influencing disease progression. Thus, modulation of AM phenotypes through molecular intervention has therapeutic potential in the treatment of asthma and other allergic inflammatory diseases. This review updated recent advances in polarization and functional specialization of these macrophage subtypes with emphasis on modulation of polarization of M2 cells in asthma of human subjects and animal models.

Aberrant Expression of Bacterial Pattern Recognition Receptor NOD2 of Basophils and Microbicidal Peptides in Atopic Dermatitis

Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease, associated with basophil infiltration into skin lesions and Staphylococcus aureus (S.aureus)-induced inflammation. Pattern recognition receptors (PRRs), including microbicidal peptide human neutrophil α-defensins (HNP) and dermcidin, can exert immunomodulating activity in innate immunity and skin inflammation. We investigated the plasma concentration of HNP and dermcidin, the expression of bacterial toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD)-like receptors of basophils and plasma concentration and ex vivo induction of AD-related inflammatory cytokines and chemokines using ELISA and flow cytometry, in AD patients and control subjects. Plasma concentrations of HNP, dermcidin and AD-related Th2 chemokines CCL17, CCL22 and CCL27 were significantly elevated in AD patients compared with controls (all p < 0.05). Plasma concentrations of CCL27 and CCL22 were found to correlate positively with SCORing atopic dermatitis (SCORAD), objective SCORAD, % area affected, lichenification and disease intensity, and CCL27 also correlated positively with pruritus in AD patients (all p < 0.05). Protein expressions of NOD2 but not TLR2 of basophils were significantly down-regulated in AD patients compared with controls (p = 0.001). Correspondingly, there were lower ex vivo % inductions of allergic inflammatory tumor necrosis factor-α, IL-6 and CXCL8 from peripheral blood mononuclear cells upon NOD2 ligand S. aureus derived muramyl dipeptide stimulation in AD patients comparing with controls. The aberrant activation of bacterial PRRs of basophils and anti-bacterial innate immune response should be related with the allergic inflammation of AD.

Adenovirus-mediated interleukin-35 gene transfer suppresses allergic airway inflammation in a murine model of asthma

OBJECTIVE AND DESIGN

Asthma is thought to result from the generation of T helper type 2 (Th2) responses, leading to bronchial inflammation. Interleukin (IL)-35 is a recently described member of IL-12 cytokine family that plays a critical role in influencing Th cell differentiation and inflammatory processes. The aim of this study was to examine the effect of adenovirus expressing IL-35 (AdIL-35) on allergic airway hyperresponsiveness (AHR) and inflammation in a mouse model of asthma.

METHODS

BALB/c mice were subjected to an established model of allergic airway disease. AdIL-35 was administered intranasally and the effect of IL-35 on Th2 responses, pulmonary inflammation, goblet cell metaplasia, and AHR were assessed.

RESULTS

Transfer of AdIL-35 significantly reduced the severity of AHR and numbers of inflammatory cells and levels of IL-4, IL-5, IL-13, and IL-17 in bronchoalveolar lavage fluid, compared with administration of a control virus. Moreover, AdIL-35 elevated the numbers of CD4+CD25+Foxp3+ regulatory T cells in the lungs. Histological analysis showed that AdIL-35 inhibited allergic lung tissue inflammation and mucus hypersecretion.

CONCLUSION

These results demonstrate that adenovirus-mediated delivery of interleukin-35 gene can mitigate allergic airway inflammation in experimental asthma and suggest that IL-35 may offer a novel therapeutic approach to treat allergic asthma.

Periostin: its role in asthma and its potential as a diagnostic or therapeutic target

Accumulating evidence shows that periostin, a matricellular protein, is involved in many fundamental biological processes such as cell proliferation, cell invasion, and angiogenesis. Changes in periostin expression are commonly detected in various cancers and pre-cancerous conditions, and periostin may be involved in regulating a diverse set of cancer cell activities that contribute to tumorigenesis, cancer progression, and metastasis. Periostin has also been shown to be involved in many aspects of allergic inflammation, such as eosinophil recruitment, airway remodeling, development of a Th2 phenotype, and increased expression of inflammatory mediators. In an in vivo model, bronchoalveolar lavage (BAL) fluid obtained from ovalbumin-challenged mice was found to contain significantly higher levels of periostin compared to BAL samples from control mice. To date, the molecular mechanisms involving periostin in relation to asthma in humans have not been fully elucidated. This review will focus on what is known about periostin and its role in the pathophysiological mechanisms that mediate asthma in order to evaluate the potential for periostin to serve as a biomarker and therapeutic target for the detection and treatment of asthma, respectively.

IL-35 expression in peripheral blood CD4(+) T cells from chronic hepatitis B virus-infected patients directly correlates with virus load

Interleukin 35 (IL-35) functions in an anti-inflammatory fashion by inhibiting T-cell proliferation, whereas CD4(+) T cells play an important role in cellular immunity. In a hepatitis B virus (HBV) infection, the viral proteins stimulate the immune system to generate antiviral molecules, which correlate to HBV DNA load. We investigated the impact of HBV DNA load on the expression of IL-35 mRNA in CD4(+) T cells, and the expression of IL-35 cytokine in serum of the patients with chronic HBV infection. Here we report that the frequency of circulating CD4(+) T cells correlates with the HBV DNA load in the serum of chronic hepatitis B (CHB) patients. An increased number of CD4(+) T cells were found in those patients with higher levels of HBV DNA. Regulatory T cells (T regs) also showed this trend, but circulating cytotoxic lymphocytes (CTLs) showed a negative correlation with serum HBV DNA load. In addition, significantly more IL-35 mRNA was found in the CD4(+) T cells of CHB patients, compared to healthy controls. Patients in the high viral load group showed increased levels of IL-35 mRNA, compared with those in the low viral load group. The level of IL-35 cytokine in the serum of CHB patients was significantly higher than in the healthy controls and in those infected with HBV, the patients with a higher viral load had more serum IL-35 cytokines, compared to those with a lower viral load. Our study suggests that increased serum IL-35 could be directly related to increased levels of IL-35 mRNA in CD4(+) T cells and HBV DNA load in CHB patients. The possible role of IL-35 as an immune regulator in chronic HBV infection should be investigated further.