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

Association between single nucleotide polymorphisms of interleukin-35 genes and atopic dermatitis

Introduction

The pathogenesis of atopic dermatitis (AD) involves complex interactions between environmental factors, the skin microbiome, epidermal barrier defects, and altered immune responses that develop on a not fully understood specific genetic background.

Aim

We aimed to evaluate the contribution of single nucleotide polymorphisms (SNPs) in the IL-35 genes (IL-12A and EBI3) towards AD susceptibility and clinical characteristics of AD in the Polish population. Two SNPs (rs568408, rs582054) in IL-12A and one SNP (rs428253) in EBI3 were selected.

Material and methods

Blood samples were collected from 202 AD patients and 178 healthy individuals. SNPs in IL-35 genes were analysed by the polymerase chain reaction with sequence-specific primers (SSP-PCR) method.

Results

For IL-12A rs568408, the AA genotype was significantly linked to increased odds of AD (OR = 34.61; 95% CI: 2.06-579.97, p = 0.0137) and marginally associated with normal total serum IgE levels (OR = 2.82; 95% CI: 0.97-8.16; p = 0.05), while the GA genotype showed significantly reduced odds of AD (OR = 0.53; 95% CI: 0.34-0.81; p = 0.0035). In the context of IL-12A rs582054, TT genotype carriers had increased odds of AD (OR = 2.05; 95% CI: 1.08-3.85; p = 0.03). Patients with the GG genotype of EBI3 rs428253 had decreased odds of high total serum IgE levels (OR = 0.42; 95% CI: 0.20-0.86; p = 0.02) and milder pruritus severity compared to CC genotype carriers (4.12 vs. 7.50; p = 0.02).

Conclusions

IL-35 genetic variations appear to play a role in AD pathogenesis.

Extracellular vesicle miRNAs drive aberrant macrophage responses in NSAID-exacerbated respiratory disease

BACKGROUND

Extracellular vesicles (EVs) have been implicated in the pathogenesis of asthma, however, how EVs contribute to immune dysfunction and type 2 airway inflammation remains incompletely understood. We aimed to elucidate roles of airway EVs and their miRNA cargo in the pathogenesis of NSAID-exacerbated respiratory disease (N-ERD), a severe type 2 inflammatory condition.

METHODS

EVs were isolated from induced sputum or supernatants of cultured nasal polyp or turbinate tissues of N-ERD patients or healthy controls by size-exclusion chromatography and characterized by particle tracking, electron microscopy and miRNA sequencing. Functional effects of EV miRNAs on gene expression and mediator release by human macrophages or normal human bronchial epithelial cells (NHBEs) were studied by RNA sequencing, LC-MS/MS and multiplex cytokine assays.

RESULTS

EVs were highly abundant in secretions from the upper and lower airways of N-ERD patients. N-ERD airway EVs displayed profoundly altered immunostimulatory capacities and miRNA profiles compared to airway EVs of healthy individuals. Airway EVs of N-ERD patients, but not of healthy individuals induced inflammatory cytokine (GM-CSF and IL-8) production by NHBEs. In macrophages, N-ERD airway EVs exhibited an impaired potential to induce cytokine and prostanoid production, while enhancing M2 macrophage activation. Let-7 family miRNAs were highly enriched in sputum EVs from N-ERD patients and mimicked suppressive effects of N-ERD EVs on macrophage activation.

CONCLUSION

Aberrant airway EV miRNA profiles may contribute to immune dysfunction and chronic type 2 inflammation in N-ERD. Let-7 family miRNAs represent targets for correcting aberrant macrophage activation and mediator responses in N-ERD.

Human interleukin-12α and EBI3 are cytokines with anti-inflammatory functions

Interleukins are secreted proteins that regulate immune responses. Among these, the interleukin 12 (IL-12) family holds a central position in inflammatory and infectious diseases. Each family member consists of an α and a β subunit that together form a composite cytokine. Within the IL-12 family, IL-35 remains particularly ill-characterized on a molecular level despite its key role in autoimmune diseases and cancer. Here we show that both IL-35 subunits, IL-12α and EBI3, mutually promote their secretion from cells but are not necessarily secreted as a heterodimer. Our data demonstrate that IL-12α and EBI3 are stable proteins in isolation that act as anti-inflammatory molecules. Both reduce secretion of proinflammatory cytokines and induce the development of regulatory T cells. Together, our study reveals IL-12α and EBI3, the subunits of IL-35, to be functionally active anti-inflammatory immune molecules on their own. This extends our understanding of the human cytokine repertoire as a basis for immunotherapeutic approaches.

Immune profiles to distinguish hospitalized versus ambulatory COVID-19 cases in older patients

A fraction of patients with COVID-19 develops severe disease requiring hospitalization, while the majority, including high-risk individuals, experience mild symptoms. Severe disease has been associated with higher levels of antibodies and inflammatory cytokines but often among patients with diverse demographics and comorbidity status. This study evaluated hospitalized vs. ambulatory patients with COVID-19 with demographic risk factors for severe COVID-19: median age of 63, >80% male, and >85% black and/or Hispanic. Sera were collected four to 243 days after symptom onset and evaluated for binding and functional antibodies as well as 48 cytokines and chemokines. SARS-CoV-2-specific antibody levels and functions were similar in ambulatory and hospitalized patients. However, a strong correlation between anti-S2 antibody levels and the other antibody parameters, along with higher IL-27 levels, was observed in hospitalized but not ambulatory cases. These data indicate that antibodies against the relatively conserved S2 spike subunit and immunoregulatory cytokines such as IL-27 are potential immune determinants of COVID-19.

Serum IL-27 predicts the severity and prognosis in patients with community-acquired pneumonia: a prospective cohort study

Background: The previous studies have revealed that IL-27 was involved in the pathophysiology of pulmonary inflammatory diseases. However, the role of IL-27 in community-acquired pneumonia (CAP) was unclear. The goal of this research was to explore the associations of serum IL-27 with the severity and prognosis among CAP patients through a prospective cohort study. Methods: The whole of 239 healthy population and 239 CAP patients were enrolled. Fasting blood samples were collected. Inflammatory cytokines were detected using enzyme linked immunosorbent assay (ELISA). Demographic characteristics and clinical information were analyzed. Results: Serum IL-27 on admission was significantly risen in CAP patients compared with control subjects. Besides, serum IL-27 was gradually increased in line with CAP severity scores. Correlative analysis suggested that serum IL-27 was associated with blood routine indices, renal function, liver function, myocardial function and inflammatory cytokines. Linear and logistic regression analyses revealed that serum IL-27 was positively correlated with CAP severity scores. Logistic regression analysis demonstrated that serum higher IL-27 on admission elevated the risks of vasoactive agent usage and longer hospital stay during hospitalization among CAP patients. Conclusions: Serum IL-27 is markedly and positively associated with the severity and poor prognosis among CAP patients, indicating that IL-27 may involve in the pathophysiological process of CAP. Serum IL-27 may be used as a biomarker for diagnosis and prognosis in CAP patients.

EBV-induced gene 3 augments IL-23Rα protein expression through a chaperone calnexin

Epstein-Barr virus-induced gene 3 (EBI3) is a subunit common to IL-27, IL-35, and IL-39. Here, we explore an intracellular role of EBI3 that is independent of its function in cytokines. EBI3-deficient naive CD4+ T cells had reduced IFN-γ production and failed to induce T cell-dependent colitis in mice. Similarly reduced IFN-γ production was observed in vitro in EBI3-deficient CD4+ T cells differentiated under pathogenic Th17 polarizing conditions with IL-23. This is because the induction of expression of one of the IL-23 receptor (IL-23R) subunits, IL-23Rα, but not another IL-23R subunit, IL-12Rβ1, was selectively decreased at the protein level, but not the mRNA level. EBI3 augmented IL-23Rα expression via binding to the chaperone molecule calnexin and to IL-23Rα in a peptide-dependent manner, but not a glycan-dependent manner. Indeed, EBI3 failed to augment IL-23Rα expression in the absence of endogenous calnexin. Moreover, EBI3 poorly augmented the expression of G149R, an IL-23Rα variant that protects against the development of human colitis, because binding of EBI3 to the variant was reduced. Taken together with the result that EBI3 expression is inducible in T cells, the present results suggest that EBI3 plays a critical role in augmenting IL-23Rα protein expression via calnexin under inflammatory conditions.

The immunomodulatory potentials of interleukin-27 in airway allergies

Allergic airway disorders such as asthma and allergic rhinitis are mainly caused by inhaled allergen-induced improper activation and responses of immune and non-immune cells. One important response is the production of IL-27 by macrophages and dendritic cells (DCs) during the early stage of airway allergies. IL-27 exerts powerful modulatory influences on the cells of innate immunity [eg neutrophils, eosinophils, mast cells, monocytes, macrophages, dendritic cells (DCs), innate lymphoid cells (ILCs), natural killer (NK) cells and NKT cells)] and adaptive immunity (eg Th1, Th2, Th9, Th17, regulatory T, CD8⁺ cytotoxic T and B cells). The IL-27-mediated signalling pathways may be modulated to attenuate asthma and allergic rhinitis. In this review, a comprehensive discussion concerning the roles carried out by IL-27 in asthma and allergic rhinitis was provided, while evidences are presented favouring the use of IL-27 in the treatment of airway allergies.

Association between IL-27 and Tr1 cells in severe form of paracoccidioidomycosis

Interleukin-27, a cytokine of the IL-12 family, is secreted by antigen-presenting cells such as macrophages and dendritic cells (DCs). Recent studies suggest an anti-inflammatory role for IL-27 by inducing IL-10 producing Tr1 cells capable of inhibiting Th1 and Th17 type responses. Our study aimed to investigate the involvement of IL-27 and Tr1 cells in the immunomodulation of paracoccidioidomycosis (PCM), the most prevalent systemic mycosis in Brazil. The presence of IL-27 was evaluated in serum and biopsies of patients with PCM by ELISA, immunohistochemistry, and immunofluorescence. The presence of Tr1 in peripheral blood was analyzed by flow cytometry. In vitro assays were performed to verify the ability of P. brasiliensis yeast to induce IL-27 production by DCs and macrophages, as well as the polarization of lymphocytes to the Tr1 phenotype. Patients with the acute form and severe chronic form, the most severe and disseminated forms of PCM, presented higher serum concentrations of IL-27 and higher percentage of Tr1 cells compared to patients with mild chronic form. IL-27 was also detected in lesions of patients with PCM and associated with DCs and macrophages. P. brasiliensis Pb18 yeasts were able to induce IL-27 production by both DCs and macrophages. We found that DCs pulsed with Pb18 were able to induce Tr1 lymphocytes in vitro. Our data suggest that IL-27 and Tr1 cells could contribute to the deficient immune response to P. brasiliensis that leads to severe and disseminated forms of the disease.

Metformin exhibits its therapeutic effect in the treatment of pre-eclampsia via modulating the Met/H19/miR-148a-5p/P28 and Met/H19/miR-216-3p/EBI3 signaling pathways

Metformin (Met) has been found to modify the methylation of H19 and to alter its expression. In addition, IL-27, one of the downstream factors in the H19 signaling pathway, plays an important role in the pathogenesis of pre-eclampsia (PE). In this study, we investigated the molecular mechanism underlying the therapeutic effect of Met in the management of PE both in vivo and in vitro. The role of H19 signaling pathway in PE was validated using online bioinformatics tools, luciferase assays, real-time PCR and Western Blot. A tail-cuff method was used to examine the blood pressures in PE rats with or without Met treatment. Cells exhibited a dose-dependent increase of H19 methylation, which inhibited the expression of H19. Additionally, upon the Met treatment, levels of miR-148-5p and miR-216-3p were both elevated in a dose-dependent manner while levels of p28 mRNA and EBI3 mRNA were both inhibited by Met treatment. Also, H19 was found to regulate the expression of miR-148a-5p and miR-216-3p, while P28 and EBI3 were respectively identified as target genes of miR-148a-5p and miR-216-3p. Therefore, the Met/H19/miR-148a-5p/P28 and Met/H19/miR-216-3p/EBI3 signaling pathways were implicated in the pathogenesis of PE. Met was implicated in the pathogenesis of PE via modulating the H19 signaling pathway. The methylation of H19 reduced H19 expression, which in turn could up-regulate the expression of miR-148-5p/miR-216-3p. And the expressions of subunits of IL-27, P28 and EBI3, were thus suppressed. Therefore, Met-induced inhibition of H19 also led to the reduction of IL-27 expression, TNF-α and IL-6 in vivo.

Regulatory cytokine function in the respiratory tract

The respiratory tract is an important site of immune regulation; required to allow protective immunity against pathogens, while minimizing tissue damage and avoiding aberrant inflammatory responses to inhaled allergens. Several cell types work in concert to control pulmonary immune responses and maintain tolerance in the respiratory tract, including regulatory and effector T cells, airway and interstitial macrophages, dendritic cells and the airway epithelium. The cytokines transforming growth factor β, interleukin (IL-) 10, IL-27, and IL-35 are key coordinators of immune regulation in tissues such as the lung. Here, we discuss the role of these cytokines during respiratory infection and allergic airway disease, highlighting the critical importance of cellular source and immunological context for the effects of these cytokines in vivo.

IL-35 recombinant protein reverses inflammatory bowel disease and psoriasis through regulation of inflammatory cytokines and immune cells

Interleukin‐35 (IL‐35), a member of the IL‐12 family, functions as a new anti‐inflammatory factor involved in arthritis, psoriasis, inflammatory bowel disease (IBD) and other immune diseases. Although IL‐35 can significantly prevent the development of inflammation in many diseases, there have been no early studies accounting for the role of IL‐35 recombinant protein in IBD and psoriasis. In this study, we assessed the therapeutic potential of IL‐35 recombinant protein in three well‐known mouse models: the dextransulfate sodium (DSS)‐induced colitis mouse model, the keratin14 (K14)‐vascular endothelial growth factor A (VEGF‐A)‐transgenic (Tg) psoriasis mouse model and the imiquimod (IMQ)‐induced psoriasis mouse model. Our results indicated that IL‐35 recombinant protein can slow down the pathologic process in DSS‐induced acute colitis mouse model by decreasing the infiltrations of macrophages, CD4⁺T and CD8⁺T cells and by promoting the infiltration of Treg cells. Further analysis demonstrated that IL‐35 recombinant protein may regulate inflammation through promoting the secretion of IL‐10 and inhibiting the expression of pro‐inflammatory cytokines such as IL‐6, TNF‐α and IL‐17 in acute colitis model. In addition, lower dose of IL‐35 recombinant protein could achieve long‐term treatment effects as TNF‐α monoclonal antibody did in the psoriasis mouse. In summary, the remarkable therapeutic effects of IL‐35 recombinant protein in acute colitis and psoriasis mouse models indicated that IL‐35 recombinant protein had a variety of anti‐inflammatory effects and was expected to become an effective candidate drug for the treatment of inflammatory diseases.

IL-35 Suppresses Lipopolysaccharide-Induced Airway Eosinophilia in EBI3-Deficient Mice

EBI3 functions as the subunit of immune-regulatory cytokines, such as IL-27 and IL-35, by pairing with p28 and p35, respectively. We treated wild-type and EBI3-deficient mice with intratracheal administration of LPS and obtained bronchoalveolar lavage fluid (BALF) 24 h later. Although neutrophils were the predominant cells in BALF from both groups of mice, eosinophils were highly enriched and there was increased production of eosinophil-attracting chemokines CCL11 and CCL24 in BALF of EBI3-deficient mice. The bronchial epithelial cells and alveolar macrophages were the major producers of CCL11 and CCL24. Because no such increases in eosinophils were seen in BALF of p28/IL-27-deficient mice or WSX-1/IL-27Rα subunit-deficient mice upon intratracheal stimulation with LPS, we considered that the lack of IL-35 was responsible for the enhanced airway eosinophilia in EBI3-deficient mice. In vitro, IL-35 potently suppressed production of CCL11 and CCL24 by human lung epithelial cell lines treated with TNF-α and IL-1β. IL-35 also suppressed phosphorylation of STAT1 and STAT3 and induced suppressor of cytokine signaling 3. In vivo, rIL-35 dramatically reduced LPS-induced airway eosinophilia in EBI3-deficient mice, with concomitant reduction of CCL11 and CCL24, whereas neutralization of IL-35 significantly increased airway eosinophils in LPS-treated wild-type mice. Collectively, our results suggest that IL-35 negatively regulates airway eosinophilia, at least in part by reducing the production of CCL11 and CCL24.

IL-27 suppresses type 2 immune responses in vivo via direct effects on group 2 innate lymphoid cells

Group 2 innate lymphoid cells (ILC2) were recently characterized by their ability to produce significant amounts of type-2 signature cytokines and drive central beneficial and pathological features of type-2 immune responses. Although factors such as IL-33 and IL-25 were shown to have ILC2 activating capacity, it is not well understood, how ILC2 responses are regulated in vivo. Here we provide compelling evidence that IL-27-signalling directly inhibits ILC2 responses and reveal a novel mechanism for negative regulation of the innate arm of type-2 immunity. We demonstrate that IL-27-deficiency is linked to increased mucosal presence of ILC2 in a model of inflammatory lung disease. Moreover, IL-27-treatment inhibited ILC2 proliferation and cytokine production and significantly reduced their accumulation in vivo. During helminth infection, regulation of ILC2 by IL-27 directly impacted anti-parasitic immunity. Thus, therapeutic modulation of the IL-27/IL-27R axis may be relevant in a number of inflammatory conditions associated with dysregulated type-2 responses.

The biology of interleukin-27 reveals unique pro- and anti-inflammatory functions in immunity

Interleukin (IL)-27 is a multifaceted heterodimeric cytokine with pronounced pro- and anti-inflammatory as well as immunoregulatory functions. It consists of the two subunits p28/IL-30 and Epstein Bar virus-induced protein 3 (EBI3). EBI3 functions as a soluble α-receptor, and IL-27 can therefore directly activate its target cells through a heterodimer of glycoprotein 130 (gp130) and WSX-1. Being a heterodimeric cytokine that signals through gp130, IL-27 is either grouped into the IL-6 or the IL-12 family of cytokines. Originally identified as an IL-12-like cytokine that induces proliferation of CD4+ T cells and production of IFN-γ more than ten years ago, subsequent research revealed a much broader role of IL-27 in inflammation, cancer development and regulation and differentiation of immune cells. In this review, we summarize the current biochemical and molecular knowledge about the signal transduction of IL-27. Based on this, we highlight functional overlaps and plasticity with other cytokines and cytokine receptors of the IL-6/IL-12 superfamily, and describe the important role of IL-27 with regard to the differentiation of T cells, infections and cancer development. We further discuss IL-27 as a therapeutic target and how specific blockade of this cytokine could be achieved.

Interleukin-27 and interleukin-23 in patients with systemic lupus erythematosus: possible role in lupus nephritis

OBJECTIVES

To analyse the concentration of interleukin (IL)-27 and IL-23 in serum and urine of patients with systemic lupus erythematosus (SLE) compared with healthy controls (HC).

METHOD

An enzyme-linked immunosorbent assay (ELISA) was used to analyse the serum and urine concentration of IL-27 and IL-23 from 50 patients with lupus nephritis (LN), 55 patients without LN, and 30 HC. The correlations between the levels of IL-27, IL-23, and disease activity, clinical parameters in SLE patients were analysed.

RESULTS

The levels of IL-27 and IL-23 increased significantly in the serum and urine of SLE patients with and without LN compared with HC. Moreover, urine levels of IL-27 and IL-23 were correlated with the renal SLE Disease Activity Index (rSLEDAI) score and 24-h urinary protein levels. After 6 months of immunosuppressive treatment, urine IL-27 expression rose significantly in SLE patients with LN.

CONCLUSIONS

IL-27 and IL-23 may be involved in the pathogenesis of LN.

Upregulation of interleukin-35 subunits in regulatory T cells in a murine model of allergic rhinitis

OBJECTIVE

Regulatory T (Treg) cells play a critical role in the pathophysiology of allergic rhinitis (AR). We investigated the regulatory roles of interleukin (IL)-35, an immunosuppressive cytokine expressed by CD4(+)CD25(+)Foxp3(+) Treg cells, in a murine model of AR.

METHODS

The expression of IL-35 subunits (Ebi3, encoded by Ebi3, and IL-12p35, encoded by IL12a) and IL-35 receptor chains (IL12rb and IL6st) in nasal mucosa and in spleen-derived Treg cells from ovalbumin (OVA)-sensitized AR was analyzed by immunohistochemistry and quantitative real-time RT-PCR techniques.

RESULTS

IL-35 subunit secretion was associated with local OVA sensitization in this murine model of AR. Ebi3 and IL-12p35, as well as CD3, were expressed differentially in the same regions of nasal mucosa of both AR and control animals. Ebi3 mRNA levels were significantly downregulated in the nasal mucosa of AR mice compared with control mice. Similarly, Ebi3 and IL12a mRNA levels were significantly upregulated in CD4(+)CD25(+) Treg cells and, correspondingly, downregulated in CD4(+)CD25(-) T effector (Teff) cells. IL6st mRNA levels were also significantly downregulated in CD4(+)CD25(-) Teff cells.

CONCLUSIONS

Decreased Ebi3 may have a crucial regulatory effect on the nasal mucosa in AR. The increased IL-35 subunit expression in CD4(+)CD25(+) Treg cells may contribute to regulating the pathogenesis of AR.

The immunobiology of IL-27

Like many cytokines, IL-27 has pleiotropic properties that can limit or enhance ongoing immune responses depending on context. Thus, under certain circumstances, IL-27 can promote TH1 differentiation and has been linked to the activation of CD8(+) T cells and enhanced humoral responses. However, IL-27 also has potent inhibitory properties and mice that lack IL-27 mediated signaling develop exaggerated inflammatory responses in the context of infection or autoimmunity. This chapter reviews in depth the biology of IL-27, including the initial discovery, characterization, and signaling mediated by IL-27 as well as more recent insights into the molecular and cellular basis for its pleiotropic effects. Many of these advances are relevant to human diseases and highlight the potential of therapies that harness the regulatory properties of IL-27.

The molecular mechanisms of regulatory T cell immunosuppression

CD4⁺CD25⁺Foxp3⁺ T lymphocytes, known as regulatory T cells or T(regs), have been proposed to be a lineage of professional immune suppressive cells that exclusively counteract the effects of the immunoprotective "helper" and "cytotoxic" lineages of T lymphocytes. Here we discuss new concepts on the mechanisms and functions of T(regs). There are several key points we emphasize: 1. Tregs exert suppressive effects both directly on effector T cells and indirectly through antigen-presenting cells; 2. Regulation can occur through a novel mechanism of cytokine consumption to regulate as opposed to the usual mechanism of cytokine/chemokine production; 3. In cases where CD4⁺ effector T cells are directly inhibited by T(regs), it is chiefly through a mechanism of lymphokine withdrawal apoptosis leading to polyclonal deletion; and 4. Contrary to the current view, we discuss new evidence that T(regs), similar to other T-cells lineages, can promote protective immune responses in certain infectious contexts (Chen et al., 2011; Pandiyan et al., 2011). Although these points are at variance to varying degrees with the standard model of T(reg) behavior, we will recount developing findings that support these new concepts.

Transcriptional characteristics of CD4 T cells in young asthmatic children: RORC and FOXP3 axis

Background

Asthma is a chronic inflammatory disorder, hypothetically caused by autoreactive Th2 cells, whereas Th1 and regulatory T cells may confer protection. The development of Th subpopulations is dependent on the expression of lineage-specific transcription factors.

Purpose

This study aimed to assess the balance of CD4⁺ T cell populations in asthmatic children.

Methods

Peripheral blood mononuclear cells (PBMC) mRNA expression was assessed in 30 asthmatic children (18 patients with mild asthma and 12 with moderate asthma). Real-time polymerase chain reaction (RT-PCR) quantified TBX21, GATA-3, RORC, FOXP3, and EBI3 mRNA expression. Intracellular cytokine expression of IL-2, IL-4, IL-10, and IFN-γ in CD4⁺ T cells in asthmatic children was measured by flow cytometry. IL-6 and IL-17 cytokines were assessed in serum by enzyme-linked immunosorbent assay (ELISA).

Results

A significant increase was found in the percentage of CD4⁺ and CD8⁺ T cell-producing IL-4, IL-6, and IL-17. A decreased percentage of CD4⁺ producing IFN-γ in asthmatic children was found. Expression of GATA-3 (Th2), retinoid-related orphan receptor C (RORC) (Th17), and EBI3 were increased in asthmatic patients compared to healthy controls. Expression of FOXP3 (Treg) and TBX21 (Th1) were decreased (P < 0.0001 and P < 0.0001) in asthmatic children. Analysis of transcription factor ratios revealed an increase in the RORC/FOXP3 (P = 0.0001), and a significant decrease of TBX21/GATA-3 (P = 0.0001) ratios in patients with asthma.

Conclusion

Young asthmatics were characterized by increased IL-4 production and low IFN-γ synthesis. The increased serum IL-17 and IL-6 levels sustained an inflammatory environment in young asthmatics. The results indicate that FOXP3 and RORC mRNA expression could be associated with the sustained inflammatory process, transduced by low immune tolerance by Treg cells. The TBX21/GATA-3 and RORC/FOXP3 ratios dysregulation in asthmatics is consistent with the plasticity existing between Th1, Th17, and Treg cells during inflammation.