Differential expression of mRNA for Th1 and Th2 cytokine-associated transcription factors and suppressors of cytokine signalling in peripheral blood mononuclear cells of patients with atopic dermatitis

Potential Protective Factors for Allergic Rhinitis Patients Infected with COVID-19

At the beginning of the 2019 coronavirus disease (COVID-19) pandemic, airway allergic diseases such as asthma and allergic rhinitis (AR) were considered as risk factors for COVID-19, as they would aggravate symptoms. With further research, more and more literature has shown that airway allergic disease may not be a high-risk factor, but may be a protective factor for COVID-19 infection, which is closely related to its low-level expression of the ACE2 receptor and the complex cytokines network as underlying molecular regulatory mechanisms. In addition, steroid hormones and age factors could not be ignored. In this review, we have summarized some current evidence on the relationship between COVID-19 and allergic rhinitis to highlight the underlying mechanisms of COVID-19 infection and provide novel insights for its prevention and treatment. The key findings show that allergic rhinitis and its related molecular mechanisms may have a protective effect against COVID-19 infection.

A DNA circuit that records molecular events

Characterizing the relative onset time, strength, and duration of molecular signals is critical for understanding the operation of signal transduction and genetic regulatory networks. However, detecting multiple such molecules as they are produced and then quickly consumed is challenging. A MER can encode information about transient molecular events as stable DNA sequences and are amenable to downstream sequencing or other analysis. Here, we report the development of a de novo molecular event recorder that processes information using a strand displacement reaction network and encodes the information using the primer exchange reaction, which can be decoded and quantified by DNA sequencing. The event recorder was able to classify the order at which different molecular signals appeared in time with 88% accuracy, the concentrations with 100% accuracy, and the duration with 75% accuracy. This simultaneous and highly programmable multiparameter recording could enable the large-scale deciphering of molecular events such as within dynamic reaction environments, living cells, or tissues.

Inflammatory Skin Diseases: Focus on the Role of Suppressors of Cytokine Signaling (SOCS) Proteins

Inflammatory skin diseases include a series of disorders characterized by a strong activation of the innate and adaptive immune system in which proinflammatory cytokines play a fundamental role in supporting inflammation. Skin inflammation is a complex process influenced by various factors, including genetic and environmental factors, characterized by the dysfunction of both immune and non-immune cells. Psoriasis (PS) and atopic dermatitis (AD) are the most common chronic inflammatory conditions of the skin whose pathogeneses are very complex and multifactorial. Both diseases are characterized by an immunological dysfunction involving a predominance of Th1 and Th17 cells in PS and of Th2 cells in AD. Suppressor of cytokine signaling (SOCS) proteins are intracellular proteins that control inflammatory responses by regulating various signaling pathways activated by proinflammatory cytokines. SOCS signaling is involved in the regulation and progression of inflammatory responses in skin-resident and non-resident immune cells, and recent data suggest that these negative modulators are dysregulated in inflammatory skin diseases such as PS and AD. This review focuses on the current understanding about the role of SOCS proteins in modulating the activity of inflammatory mediators implicated in the pathogenesis of inflammatory skin diseases such as PS and AD.

Aberrant expression of suppressor of cytokine signaling (SOCS) molecules contributes to the development of allergic diseases

Suppressor of cytokine signalling (SOCS) proteins bind to certain cytokine receptors, Janus kinases and signalling molecules to regulate signalling pathways, thus controlling immune and inflammatory responses. Dysregulated expression of various types of SOCS molecules was indicated in multiple types of allergic diseases. SOCS1, SOCS2, SOCS3, SOCS5, and cytokine-inducible SH2 domain protein (CISH) can differentially exert anti-allergic impacts through different mechanisms, such as suppressing Th2 cell development and activation, reducing eosinophilia, decreasing IgE production, repressing production of pro-allergic chemokines, promoting Treg cell differentiation and activation, suppressing Th17 cell differentiation and activation, increasing anti-allergic Th1 responses, inhibiting M2 macrophage polarization, modulating survival and development of mast cells, reducing pro-allergic activity of keratinocytes, and suppressing pulmonary fibrosis. Although some anti-allergic effects were attributed to SOCS3, it can perform pro-allergic impacts through several pathways, such as promoting Th2 cell development and activation, supporting eosinophilia, boosting pro-allergic activity of eosinophils, increasing IgE production, enhancing the expression of the pro-allergic chemokine receptor, reducing Treg cell differentiation, increasing pro-allergic Th9 responses, as well as supporting mucus secretion and collagen deposition. In this review, we discuss the contrasting roles of SOCS proteins in contexts of allergic disorders to provide new insights regarding the pathophysiology of these diseases and possibly explore SOCS proteins as potential therapeutic targets for alleviating allergies.

Gene variants and mRNA expression analysis of SOCS3 and its association with serum IL-4 levels in atopic diseases

BACKGROUND

The suppressors of cytokine signaling (SOCS) are a class of negative regulators for several aspects of cytokine signaling that have been attributed to the pathophysiology of inflammatory disorders. Given the role of the SOCS3 gene in regulating Th2 cell proliferation, our study aimed to analyze two SOCS3 SNPs viz. rs8074003 and rs7222391, and their potential influence on IL-4 levels and SOCS3 mRNA expression besides analyzing the interaction of the SOCS3 genotypes with the various clinicopathological parameters.

METHODS

A total of 314 subjects including 154 atopic cases and 160 healthy controls were genotyped for SOCS3 polymorphisms by PCR-RFLP. SOCS3 mRNA was quantified by Real-Time PCR. The serum IL-4 and total IgE levels were determined by ELISA and Vitamin-D levels were quantified by chemiluminescence.

RESULTS

The CC genotype of rs8074003 was more frequent in atopic cases and posed a 3- fold risk of atopy (p = 0.001) whereas CG and GG genotypes were widespread in the controls (p = 0.1). For the other SNP rs7222391, there was no difference in genotypic and allelic distribution. The SOCS3 mRNA expression and serum IL-4 levels were substantially increased in the atopic cases with a significant positive correlation between them (p < 0.05).

CONCLUSION

SOCS3 SNP rs8074003 poses a convincing risk of atopic disease development. The SOCS3 expression and IL-4 levels were up-regulated in total atopy and in its different presentations. It seems plausible to target SOCS3 and IL-4 as a potential target for the diagnosis of atopy and for the development of reliable personalized therapeutic strategies to control atopic conditions.

Potential Natural Biomolecules Targeting JAK/STAT/SOCS Signaling in the Management of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease caused by the dysregulation of cytokines and other immune mediators. JAK/STAT is a classical signal transduction pathway involved in various biological processes, and its dysregulation contributes to the key aspects of AD pathogenesis. Suppressor of cytokine signaling (SOCS) proteins negatively regulate the immune-related inflammatory responses mediated by the JAK/STAT pathway. JAK/STAT-mediated production of cytokines including IL-4, IL-13, IL-31, and TSLP inhibits the expression of important skin barrier proteins and triggers pruritus in AD. The expression of SOCS proteins regulates the JAK-mediated cytokines and facilitates maintaining the skin barrier disruptions seen in AD. STATs are crucial in dendritic-cell-activated Th2 cell differentiation in the skin, releasing inflammatory cytokines, indicating that AD is a Th2-mediated skin disorder. SOCS proteins aid in balancing Th1/Th2 cells and, moreover, regulate the onset and maintenance of Th2-mediated allergic responses by reducing the Th2 cell activation and differentiation. SOCS proteins play a pivotal role in inflammatory cytokine-signaling events that act via the JAK/STAT pathway. Therapies relying on natural products and derived biomolecules have proven beneficial in AD when compared with the synthetic regimen. In this review, we focused on the available literature on the potential natural-product-derived biomolecules targeting JAK/STAT/SOCS signaling, mainly emphasizing the SOCS family of proteins (SOCS1, SOCS3, and SOCS5) acting as negative regulators in modulating JAK/STAT-mediated responses in AD pathogenesis and other inflammatory disorders.

Epidermal Growth Factor Attenuated the Expression of Inflammatory Cytokines in Human Epidermal Keratinocyte Exposed to Propionibacterium acnes

Background

While the beneficial effects of topical epidermal growth factor (EGF) on wound healing have been repeatedly reported, there are few reports about the effects of EGF on inflammatory skin diseases including acne.

Objective

To clarify the effects of EGF on acne, it was investigated whether recombinant human EGF (rhEGF) signalling can affect Propionibacterium acnes-induced cytokine expression in human epidermal keratinocytes.

Methods

The cultured normal human epidermal keratinocytes (NHK) were co-treated with P. acnes and rhEGF, and mRNA levels of interleukin (IL)-1α, IL-8 and tumor necrosis factor (TNF)-α; toll-like receptor 2 (TLR2); and nuclear factor kappa B (NF-κB) were determined. Specific enzyme-linked immunosorbent assay kits were used to measure the IL-1α, IL-8 and TLR2 expression as well as the NF-κB activation in P. acnes and rhEGF-treated NHK. After infecting the cultured NHK with live P. acnes, an increased expression of IL-1α, IL-8 and TNF-α was detected, which was prevented by rhEGF co-treatment.

Results

TLR2 and NF-κB activity increased after P. acnes treatment, and rhEGF treatment decreased TLR2 expression and NF-κB activity dose-dependently. The inhibition of EGF receptor by gefitinib attenuated the inhibitory effect of rhEGF on these increased expressions of proinflammatory cytokines and TLR2 and activity of NF-κB in NHK stimulated by P. acnes.

Conclusion

These results suggest that EGF attenuated P. acnes-induced inflammatory responses, at least in part, through the modulation of TLR2 signalling, and the topical application of rhEGF may be beneficial to relieve the inflammatory reactions of acne.

Expression of Th1 and Th2 Cytokine and Associated Transcription Factors in Peripheral Blood Mononuclear Cells and Correlation with Disease Severity

BACKGROUND

Psoriasis is a T cell-mediated autoimmune disease in patients with elevated levels of proinflammatory cytokines belonging mainly to the Th1 pathway. We investigated whether treatment of psoriasis patients with methotrexate (MTX), along with micronutrients, modulated mRNA expression of Th1 and Th2 components and whether expression of these components correlated with psoriasis severity.

METHODS

Thirty plaque-type psoriasis patients with Psoriasis Area and Severity Index (PASI) scores greater than 10 were recruited; these were 15 non-micronutrients taking- (NMT) patients treated with MTX daily (0.2-0.3 mg/kg/week), and 15 micronutrients taking- (MT) patients treated with MTX plus a micronutrient supplement daily, for 12 weeks. Blood samples were collected immediately before treatment (baseline) and after 12 weeks of treatment. Taqman quantitative real-time polymerase chain reaction (qPCR) was applied to analyze the expression of the Th1 components T-bet, interleukin-12 (IL-12), and interferon-gamma (IFN-Υ), and the Th2 components GATA-3 and interleukin-4 (IL-4). Disease severity was measured using the PASI scoring system.

RESULTS

Significant clinical improvement in the MT group coincided with significant down-regulation of Th1 and up-regulation of Th2 markers (P<0.05). With respect to the PASI-75, (defined as a 75% or greater reduction in the PASI score) cut-off point, expression of IFN-γ in the MT group with PASI scores above 75 was significantly less than that of patients in the NMT group (P=0.05). Also, GATA3 and IL-4 mRNA expression in the MT group with PASI scores greater than above 75 was significantly greater than that of patients in the NMT group (P=0.05 and 0.04, respectively).

CONCLUSION

Based on significant attenuation of the PASI score, which correlated with upregulation of Th2 pathway markers in the MT group, we recommend administration of micronutrients combined with MTX for psoriasis patients. Our results contribute to a better understanding of methotrexate immunepathogenesis mechanisms and their correlations to clinical responses in psoriasis.

Differential Expression of T-bet and GATA3 in Egyptian Children with Idiopathic Thrombocytopenic Purpura

GATA3 and T-box (T-bet) expressed in T-cells are transcriptional factors that play a critical role in development of Th2 and Th1 immunity respectively. GATA3 is expressed during Th2 differentiation and T-bet is expressed exclusively in Th1 cells. Thus, a balance between GATA3 and T-bet is believed to control Th2/Th1 polarization. Therefore, the high expression of T-bet and low expression of GATA3 indicate the existence of Th1 polarization in children with acute immune thrombocytopenic purpura (ITP). This might be related to the regulation of T-bet and GATA3. The objective of this work was to study the expression of transcriptional factors T-bet and GATA3 m RNA in children with idiopathic thrombocytopenic purpura and correlate it with clinical findings, laboratory findings, and outcome of patients. In this study the expression of T-bet and GATA3 genes was analysed in 20 normal healthy individuals and 40 children with ITP (20 acute and 20 persistent) using reverse transcriptase polymerase chain reaction to investigate a possible relation, association or correlation with the type of ITP and prognosis. T-bet was expressed significantly in 60 % of acute ITP children (12/20) (P value 0.001) and not expressed in persistent ITP children (0/20), while GATA3 was expressed in 25 % of persistent ITP patients (5/20) (P value 0.017) and not expressed in acute ITP patients (0/20). Both genes were not detected in healthy controls. We concluded that the high expression of T-bet and the low expression of GATA3 indicate the existence of Th1 polarization in children with acute ITP. This might be related to the regulation of T-bet and GATA3. Intensive studies of abnormal cytokine profiles in ITP have led to cytokine therapies that exploit the effects of IFN-γ on Th2 cells, but such therapies are often ineffective to develop safe and effective therapeutic tools. Targeting specific molecules such as T-bet and GATA3 may be a novel therapeutic tool in ITP.

Trichloroethylene-induced hypersensitivity dermatitis was associated with hepatic metabolic enzyme genes and immune-related genes

Trichloroethylene (TCE) is one of the common organic solvents that has been widely used in cleaning or degreasing of metal and electronic products. However, hundreds of cases of hypersensitivity dermatitis have occurred after the workers were occupationally exposed to TCE in China over the past decade. The purpose of this study was to investigate mRNA expression of hepatic metabolic enzyme genes, immune-related genes, apoptosis genes and oncogenes in patients with hypersensitivity dermatitis induced by trichloroethylene. 12 typical patients with TCE-induced hypersensitivity dermatitis were investigated as the study cases, peripheral blood samples were taken from patients and control, and real-time fluorescence PCR assay was applied for detection of mRNA expression of hepatic metabolic enzyme genes, immune-related genes, apoptosis genes and oncogenes. It was found that the relative levels of mRNA expression of CYP1A2, CYP2E1, CYP3A4 and CYP2C9 increased by 723%, 318%, 385% and 216%, respectively, when compared with control (p < 0.01 or p < 0.05); Foxp3, GATA3 and CTLA4 mRNA expression increased by 104%, 106% and 253%, respectively, in TCE patients when compared with control (p < 0.01); T-bet expression decreased by 44% when compared with control (p < 0.01); these findings indicate that some immune-related genes and hepatic metabolic enzyme genes might play an important role in the process of trichloroethylene-induced hypersensitivity dermatitis.

Analysis of Th1/Th2 response pattern for erythrodermic psoriasis

As one of the most serious types of psoriasis, pathogenesis of erythrodermic psoriasis (EP) is unclear so far. In this study, we aimed to detect the levels of Th1/Th2 cytokine-associated transcription factors and T-lymphocyte clone in peripheral blood mononuclear cells (PBMCs) derived from EP patients, and gene expression level of T-bet/GATA-3 in skin lesion. The potential role of Th1/Th2 reaction pattern played in the pathogenesis of EP was also discussed. Serum levels of IFN-γ, IL-2, IL-4 and IL-10 were quantified by ELISA among 16 EP patients, 20 psoriasis vulgaris (PV) patients and 15 healthy controls. The expression levels of T-bet/GATA-3 in the skin lesion and PBMCs were examined by real-time qPCR. The ratio of Th1/Th2 was measured by flow cytometry. The levels of IFN-γ, IL-2, IL-4 and IL-10 were higher in EP patients than in the healthy controls. The levels of IL-4 and IL-10 were 69.44±11.45 and 12.62±4.57 pg/mL, respectively, in EP patients, significantly higher than those in PV patients and healthy controls (P<0.05). Flow cytometry revealed the levels of both Th1 and Th2 in PBMCs from EP patients were higher than those in healthy controls, and the Th1/Th2 ratio was dramatically lower than in PV patients (P<0.01). The ratios of IFN-γ/IL-4 and T-bet/GATA-3 in EP patients were both less than 1.0, suggesting a reversal when compared with the other two groups. Our study indicated that the EP patients exerted a Th1/Th2 bidirectional response pattern, and the balance of Th cell subsets inclines to Th2, which might be one of the important mechanisms of EP pathogenesis.

Gene silencing of SOCS3 by siRNA intranasal delivery inhibits asthma phenotype in mice

Suppresors of cytokine signaling (SOCS) proteins regulate cytokine responses and control immune balance. Several studies have confirmed that SOCS3 is increased in asthmatic patients, and SOCS3 expression is correlated with disease severity. The objective of this study was to evaluate if delivering of SOCS3 short interfering RNA (siRNA) intranasally in lungs could be a good therapeutic approach in an asthma chronic mouse model. Our results showed that intranasal treatment with SOCS3-siRNA led to an improvement in the eosinophil count and the normalization of hyperresponsiveness to methacholine. Concomitantly, this treatment resulted in an improvement in mucus secretion, a reduction in lung collagen, which are prominent features of airway remodeling. The mechanism implies JAK/STAT and RhoA/Rho-kinase signaling pathway, because we found a decreasing in STAT3 phosphorylation status and down regulation of RhoA/Rho-kinase protein expression. These results might lead to a new therapy for the treatment of chronic asthma.

Immunochemoradiotherapy for patients with oral squamous cell carcinoma: augmentation of OK-432-induced helper T cell 1 response by 5-FU and X-ray irradiation

Eighty-one patients with oral squamous cell carcinoma (OSCC) received oral fluoropyrimidine UFT and radiotherapy (RT) with or without an immunotherapeutic agent OK-432. Both overall survival and progression-free survival of patients who received RT + UFT + OK-432 were significantly longer than those of patients who received RT + UFT (P = .0075 and P = .0175, respectively). Clinical response was also more favorable in RT + UFT + OK-432 group than in RT + UFT group (P = .0066). Next, in vitro experiments were conducted to examine the effect of 5-fluorouracil (5-FU) and X-ray irradiation in OK-432-induced immunity. Human peripheral blood mononuclear cells stimulated with OK-432 produced helper T cell 1 (Th1)-type cytokines as well as interleukin-10 (IL-10) and transforming growth factor-β (TGF-β), which are produced by Th2 and regulatory T cells (Tregs), respectively, and are inhibitory in antitumor immunity. OK-432-induced IL-10 and TGF-β but not Th1 cytokines were significantly inhibited by 5-FU and/or X-ray. 5-FU and X-ray also inhibited the expression of mRNAs for GATA-3 and Foxp3, which are transcription factors for Th2 and Tregs, respectively, but not for T-bet, a transcription factor for Th1. In addition, 5-FU and X-ray decreased the expression of mRNAs for suppressor of cytokine signaling 1 (SOCS1) and SOCS3. Antisense oligonucleotides for SOCS1 and SOCS3 markedly reduced OK-432-induced IL-10 and TGF-β. This is the first report clearly demonstrating that OK-432-based immunotherapy significantly enhanced the therapeutic effects of chemoradiotherapy in patients with OSCC as well as elucidating the mechanism of the synergistic effect of immunochemoradiotherapy in which 5-FU and radiation enhanced OK-432-induced Th1 response mediated by the inhibition of SOCS1 and SOCS3 gene expression.

Transcriptional down-regulation of suppressor of cytokine signaling (SOCS)-3 in chronic obstructive pulmonary disease

BACKGROUND

Tobacco is a leading environmental factor in the initiation of respiratory diseases and causes chronic obstructive pulmonary disease (COPD). Suppressor of cytokine signaling (SOCS) family members are involved in the pathogenesis of many inflammatory diseases and SOCS-3 has been shown to play an important role in the regulation, onset and maintenance of airway allergic inflammation indicating that SOCS-3 displays a potential therapeutic target for anti-inflammatory respiratory drugs development. Since chronic obstructive pulmonary disease (COPD) is also characterized by inflammatory changes and airflow limitation, the present study assessed the transcriptional expression of SOCS-3 in COPD.

METHODS

Real-time PCR was performed to assess quantitative changes in bronchial biopsies of COPD patients in comparison to unaffected controls.

RESULTS

SOCS-3 was significantly down-regulated in COPD at the transcriptional level while SOCS-4 and SOCS-5 displayed no change.

CONCLUSIONS

It can be concluded that the presently observed inhibition of SOCS-3 mRNA expression may be related to the dysbalance of cytokine signaling observed in COPD.

The atopic dermatitis-like symptoms induced by MC903 were alleviated in JNK1 knockout mice

Atopic dermatitis (AD) is a common allergic disease, imposing large social and economic burdens worldwide. Atopic dermatitis is characterized by eczematous skin lesions and immunoglobulin E (IgE) hypersecretion. We investigated the role of JNK1 on the development of AD in mice. The vitamin D3 analogue MC903, a psoriasis therapeutic drug, was used to induce AD-like symptoms in wild-type (WT) and JNK1-/- mice. The symptoms of AD were less severe in JNK1-/- mice compared with WT mice. JNK1-/- mice showed less ear thickening and infiltration of eosinophils and mast cells in AD-like lesions than did WT mice when treated with MC903. MC903-treated JNK1-/- mice also showed significantly lower level of serum IgE, which was elevated in MC903-treated WT mice. Splenocytes isolated from MC903-treated WT and JNK1-/- mice were stimulated with anti-CD3 and anti-CD28 monoclonal antibodies. Splenocytes from JNK1-/- mice produced lower levels of T-helper (Th2) cytokines (interleukin-4 and -13) and transcription factor GATA-binding protein 3, and produced increased levels of the Th1 cytokines interferon-γ and transcription factor T-box expressed in T cells. Our results indicate that JNK1 plays an important role in the pathogenesis of AD and may be a useful target for therapies to ameliorate AD.

SOCS proteins in development and disease

Cytokine and growth factor signaling mediates essential roles in the differentiation, proliferation, survival and function of a number of cell lineages. This is achieved via specific receptors located on the surface of target cells, with ligand binding activating key intracellular signal transduction cascades to mediate the requisite cellular outcome. Effective resolution of receptor signaling is also essential, with excessive signaling having the potential for pathological consequences. The Suppressor of cytokine signaling (SOCS) family of proteins represent one important mechanism to extinguish cytokine and growth factor receptor signaling. There are 8 SOCS proteins in mammals; SOCS1-7 and the alternatively named Cytokine-inducible SH2-containing protein (CISH). SOCS1-3 and CISH are predominantly associated with the regulation of cytokine receptor signaling, while SOCS4-7 are more commonly involved in the control of Receptor tyrosine kinase (RTK) signaling. Individual SOCS proteins are typically induced by specific cytokines and growth factors, thereby generating a negative feedback loop. As a consequence of their regulatory properties, SOCS proteins have important functions in development and homeostasis, with increasing recognition of their role in disease, particularly their tumor suppressor and anti-inflammatory functions. This review provides a synthesis of our current understanding of the SOCS family, with an emphasis on their immune and hematopoietic roles.

Lymphocyte-derived catecholamines induce a shift of Th1/Th2 balance toward Th2 polarization

AIMS

Our previous work has shown that lymphocytes synthesize and secrete catecholamines (CAs), which regulate lymphocyte proliferation and apoptosis. In the present study, we explored the effect of the lymphocyte-derived CAs on differentiation and function of T helper (Th) cells.

METHODS

Lymphocytes were separated from the mesenteric lymph nodes of mice and stimulated by concanavalin A (Con A). These cells were treated with alpha-methyl-p- tyrosine (α-MT), an inhibitor of tyrosine hydroxylase (TH) that is a rate-limiting enzyme for synthesis of CAs, and pargyline, an inhibitor of monoamine oxidase that degrades CAs.

RESULTS

Treatment of Con A-stimulated lymphocytes with α-MT (10(-6) M) reduced CAs both in the cultured lymphocytes and in the culture supernatants. Simultaneously, α-MT upregulated expression of mRNAs and proteins of T-box expressed in T cells (T-bet) and interferon-γ (IFN-γ) but downregulated expression of mRNAs and proteins of GATA binding protein 3 (GATA-3) and interleukin-4 (IL-4) in Con A-activated lymphocytes. In contrast, pargyline (10(-6) M) increased intracellular and supernatant CA contents in Con A-activated lymphocytes. Meanwhile, the treatment with pargyline downregulated expression of T-bet and IFN-γ but upregulated expression of GATA-3 and IL-4 in these lymphocytes.

CONCLUSION

CAs synthesized and secreted by lymphocytes regulate differentiation and function of Th cells, with an effect facilitating the shift of Th1/Th2 balance toward Th2 polarization.

Lesional skin in atopic dogs shows a mixed Type-1 and Type-2 immune responsiveness

Canine atopic dermatitis (AD) is a chronic inflammatory and pruritic skin disease which shares several characteristics with its human counterpart. In chronic patch test lesions of human with AD mainly a Th1-type cellular response is found. Besides, non-lesional AD skin is already skewed for inflammation and therefore different from healthy skin. The goal of this study was to characterize local immune responsiveness in chronic canine AD lesions as compared to that in non-lesional AD skin by defining T cell subset relevant cytokine- and transcription factor expression profiles. The gene expression of the Th1 cytokines IL-12p35, IL-12p40 and IFN-γ and their related transcription factors STAT4, SOCS5 and T-bet, the Th2 cytokines IL-4 and IL-13 and transcription factors STAT6, SOCS3 and GATA-3 and the regulatory cytokines IL-10 and TGF-β and the transcription factor FOXP3 was evaluated in healthy control and atopic dogs. In non-lesional (NLS) and chronic lesional skin (LS) of atopic dogs and control skin (CS) from healthy dogs mRNA expression of cytokines and transcription factors were measured by quantitative real-time PCR. Significantly different values were found for the following factors: IL-12p40 mRNA was lower in LS when compared to NLS. Expression of STAT4 was higher in LS compared to CS and NLS. More IL-13 and SOCS3 were found in LS and NLS when compared to CS and also in LS compared to NLS. GATA-3 was lower in LS compared to NLS. IL-10 expression was higher in both LS and NLS compared to CS and more IL-10 was present in LS compared to NLS. These findings indicate that both Th1- and Th2-type as well as T regulatory cells are present in NLS and LS in canine atopic skin.

Suppressors of cytokine signaling 3 expression in eosinophils: regulation by PGE₂ and Th2 cytokines

Asthma and nonasthmatic eosinophilic bronchitis (NAEB) are respiratory disorders characterized by a predominance of Th2 cells and eosinophilic inflammation. Suppressors of cytokine signaling (SOCS) proteins play an important role in Th2-mediated allergic responses through control of the balance between Th1 and Th2 cells, particularly, SOCS3 and SOCS5. The aim of this study was to analyze SOCS expression in human peripheral blood eosinophils from patients with asthma, NAEB and healthy controls. SOCS expression in eosinophils from subjects was demonstrated by different techniques. Results showed that expression of SOCS3 in eosinophils and CD4 T cells from patients was higher than in healthy subjects. In addition, we demonstrated that prostaglandin E₂ (PGE₂) and Th2 cytokines are able to upregulate SOCS3 production in eosinophils and attenuate its degranulation. In conclusion, eosinophils are able to transcribe and translate SOCS3 protein and can contribute to the regulation of the Th1/Th2 balance through SOCS3 production.

Gene expression patterns and susceptibility to allergic responses

Allergic diseases are due to hypersensitive immune responses against otherwise innocuous allergens, and involve the dysregulated expression of numerous genes in cells from both the innate and adaptive immune systems. Allergic diseases are characterized by the enhanced production of type 2 T helper (Th2) cytokines, including interleukin-4, -5 and -13. These cytokines induce many of the pathophysiologic hallmarks of allergy, and their expression is tightly regulated at the level of gene transcription by both positively and negatively-acting transcription factors. In this review, the authors summarize data indicating that some of these factors represent checkpoints in the development of allergic diseases. Th2 gene expression is also controlled at the level of chromatin remodeling, and the implications of chromatin-based Th2 gene regulation in allergic disorders is also discussed. The differentiation of Th2 cells from naive precursors is critically dependent upon instruction received from dendritic cells, although the precise signals involved in this process are not well understood. Current thinking regarding some of the environmental cues interpreted by dendritic cells during allergen encounter, and how they promote Th2 responses will be reviewed. Understanding the cross-talk between dendritic cells and T cells holds great promise for deciphering the dysregulated immune response in allergy.

T cell treatment with small interfering RNA for suppressor of cytokine signaling 3 modulates allergic airway responses in a murine model of asthma

CD4(+) T cells, particularly T helper (Th) 2 cells, play a pivotal role in the pathophysiology of allergic asthma. Suppressor of cytokine signaling (SOCS) proteins control the balance of CD4(+) T cell differentiation. Mice that lack SOCS3 in T cells by crossing SOCS3-floxed mice with Lck-Cre-transgenic mice have reduced allergen-induced eosinophilia in the airways. Here, we studied the effects of SOCS3 silencing with small interfering (si) RNA in primary CD4(+) T cells on Th2 cell differentiation and on asthmatic responses in mice. Th2 cells were generated from ovalbumin (OVA)-specific T cell receptor-transgenic mice in vitro and transferred into recipient mice. Transfection of SOCS3-specific siRNA attenuated Th2 response in vitro. Adoptive transfer of SOCS3-siRNA T cells exhibited markedly suppressed airway hyperresponsiveness and eosinophilia after OVA challenge, with a concomitant decrease in OVA-specific CD4(+) T cell accumulation in the airways. To investigate the mechanism of this impaired CD4(+) T cell accumulation, we inactivated SOCS3 of T cells by crossing SOCS3-floxed (SOCS3(flox/flox)) mice with CD4-Cre transgenic mice. CD4-Cre × SOCS3(flox/flox) mice exhibited fewer IL-4-producing cells and more reduced eosinophil infiltration in bronchoalveolar lavage fluids than control mice in a model of OVA-induced asthma. Expression of CCR3 and CCR4 in CD4(+) T cells was decreased in CD4-Cre × SOCS3(flox/flox) mice. CCR4 expression was also decreased in CD4(+) T cells after transfer of SOCS3 siRNA-treated T cells. These findings suggest that the therapeutic modulation of SOCS3 expression in CD4(+) T cells might be effective in preventing the development of allergic asthma.

Polymorphisms in the interleukin 13 and GATA binding protein 3 genes and the development of eczema during childhood

BACKGROUND

Atopic eczema is characterized by Th2-dominant immunity with the cytokine interleukin 13 and the transcription factor GATA binding protein 3 playing a critical role.

OBJECTIVES

We assessed the association of polymorphisms in the IL13 and GATA3 genes with childhood eczema.

METHODS

A birth cohort (n = 1456) was established on the Isle of Wight in 1989 and followed at the ages of 1 (n = 1167), 2 (n = 1174), 4 (n = 1218) and 10 years (n = 1373) to determine the prevalence of allergic disease including eczema. At 4 and 10 years, skin prick testing was performed. Whole blood samples (n = 923) were obtained at the 10-year assessment, stored frozen, and genotyped. Five polymorphisms from IL13 and seven from GATA3 were genotyped for this analysis. Repeated measurement analyses were conducted for the occurrence of eczema at ages 1, 2, 4 and 10 years. All analyses were adjusted for maternal and paternal eczema, low birth weight (< 2500 g), breastfeeding >or= 3 months and age.

RESULTS

IL13 was not associated with childhood eczema. For GATA3, the single nucleotide polymorphism (SNP) rs2275806 (promoter region) showed an increased odds ratio for atopic eczema independent of whether the comparison group had a positive skin prick test. The SNP rs444762 (intron 3 region) was associated with atopic eczema in comparison with children without eczema. The increased relative risks remained significant after adjustment for multiple testing only for rs2275806 (P < 0.05).

CONCLUSIONS

A SNP in GATA3 is associated with atopic eczema. This finding highlights the importance of GATA3 as an immune-modulating gene in atopic eczema.

Investigation of the eotaxin gene -426C-->T, -384A-->G and 67G-->a single-nucleotide polymorphisms and atopic dermatitis in Italian children using family-based association methods

BACKGROUND

Eotaxin plays an important role in atopic dermatitis (AD) as a potent chemoattractant and activator of eosinophils and T-helper 2 lymphocytes.

AIM

To investigate whether single-nucleotide polymorphisms of the eotaxin gene are associated with AD, we investigated the genotype and allelic frequencies of -426C-->T, -384A-->G, and 67G-->A SNPs in 130 Italian families.

METHODS

In total, 130 children with either the extrinsic allergic or intrinsic nonallergic forms of AD (EAD and IAD) were recruited from 130 families. Genotyping was performed using PCR and restriction fragment length polymorphism analysis.

RESULTS

A significant difference was observed in the genotype frequency of the -426C-->T SNP between children with EAD and those with IAD (P = 0.01), and between children with EAD and controls (P = 0.01). The allele frequencies of the -426C-->T SNP were significantly different between children with EAD and those with IAD (P < 0.01), and between children with EAD and controls (P < 0.01). For children with EAD, the genotype frequency of the -426C-->T SNP was no different between the groups with mild, moderate and severe SCORAD (P = NS). No significant association was observed between the -384A-->G and 67G-->A SNPs and the two groups of children with EAD and IAD compared with the control group. In 32 trios selected from 68 EAD families, the transmission disequilibrium test showed a preferential transmission of the -426T allele from the parents to affected offspring (P < 0.01).

CONCLUSIONS

Our results suggest that in our group of children with AD, the eotaxin gene may play a crucial role in the development of extrinsic AD, probably with other genetic factors.

Role of Txk, a member of the Tec family of tyrosine kinases, in immune-inflammatory diseases

Txk/Rlk, a member of the Tec family of tyrosine kinases, is an important signaling mediator. We previously reported that human Txk is expressed in Th1/Th0 cells, and Txk translocates from cytoplasm into nuclei upon activation. Txk regulates specifically interferon-gamma gene transcription. Txk, poly(ADP-ribose) polymerase 1, and elongation factor 1alpha make a complex to bind to interferon-gamma gene promoter region-53/-39 (Txk responsive element) to exert positive effects on transcription as a Th1 cell-associated transcription factor. Txk expression is enhanced in rheumatoid arthritis and Behçet's disease, where Th1 dominant immunity occurs. In bronchial asthma and atopic dermatitis, typical Th2 diseases, Txk expression is reduced. Modulation of Txk expression by gene transfer or similar modality may lead to the correction of aberrant immunity and, consequently, disease treatment.

SOCS3 negatively regulates the gp130-STAT3 pathway in mouse skin wound healing

Proliferation and differentiation of keratinocytes during wound healing are regulated by cytokines and chemokines, which are secreted by resident and inflammatory cells and activate the transcription factor signal transducer and activator of transcription (STAT)3. However, it is not clear to what extent STAT3 in keratinocytes is activated by gp130-containing receptors. We addressed this question genetically by deleting the suppressor of cytokine signaling (SOCS)3, a negative regulator of gp130-mediated STAT3 activation. Socs3 alleles flanked by loxP sites were deleted in mice with either an MMTV-Cre or K5-Cre transgene. While both transgenes are active in keratinocytes, the MMTV-Cre deletes floxed genes also in immune cells. Deletion of Socs3 using the MMTV-Cre transgene resulted in aberrant STAT3 activation, impaired wound healing, prolonged secretion of chemokines, a hyperproliferative epidermis, and neutrophil infiltration into wounds. Simultaneous deletion of the Socs3 and gp130 genes restored normal wound healing. Moreover, deletion of Socs3 only in keratinocytes caused impaired wound healing. These results demonstrate that wound healing is controlled in keratinocytes by the gp130-SOCS3-STAT3 pathway and an imbalance of this pathway results in delayed wound healing.

Role of suppressor of cytokine signaling in ocular allergy

PURPOSE OF REVIEW

The goal of this article is to evaluate developments in the knowledge of suppressor of cytokine signaling (SOCS) protein ocular allergy and the potential of SOCS proteins as targets for therapeutic strategies.

RECENT FINDINGS

The family of proteins designated SOCS proteins plays an important role in Th2-mediated allergic responses through the control of the balance between Th1 and Th2 cells. SOCS3 and SOCS5 are predominantly expressed in Th2 and Th1 cells, respectively, and they reciprocally inhibit the Th1 and Th2 differentiation processes. SOCS3 is highly expressed at the disease site of allergic conjunctivitis, and T-cell-specific expression of SOCS3 deteriorates clinical and pathological features of allergic conjunctivitis. Reduction of the expression level or inhibition of function clearly reduces the severity of allergic conjunctivitis. On the other hand, constitutive expression of SOCS5, a specific inhibitor of IL-4 signaling, results in reduced eosinophil infiltration. Moreover, negative regulation of the Th2-mediated response by dominant-negative SOCS3 and SOCS5 reduced the incidence of allergic conjunctivitis in a mouse model.

SUMMARY

The present article summarizes recent findings in terms of a role of SOCS protein as a negative regulator in ocular allergy and its clinical application.

In vivo levels of IL-4, IL-10, TGF-β1 and IFN-γ mRNA of the peripheral blood mononuclear cells in patients with alopecia areata in comparison to those in patients with atopic dermatitis

Alopecia areata (AA) has been considered to be supported by an aberrant expression of IFN-gamma as a result of antigen dependent immune response. On the other hand, AA sometimes concurs with atopic diseases, although the mechanism of the concurrence is not clear. This study was designed to elucidate the immune status of AA and the similarity between AA and atopic dermatitis (AD) by analysis of in vivo levels of mRNA of Th1, Th2, and suppressive cytokines of peripheral blood mononuclear cells (PBMC). Using semiquantitative RT-PCR, the levels of cytokine mRNA were measured in freshly isolated PBMC of 47 patients with AA, 15 patients with AD, and 12 healthy controls (HC). The levels of IL-4, IFN-gamma, and TGF-beta1 mRNA were lower in patients with AA than those in HC. The levels of IL-10 mRNA in AA were comparable with those in HC. Decreased levels of IFN-gamma and TGF-beta1 were also shown in patients with AD. These results indicated a similarity (decreased levels of IFN-gamma and TGF-beta1) between AD and AA based on the cytokine profile. In addition, decreased levels of IL-4 mRNA in AA might also explain the experience that the severity of atopic disease coincident with AA is mild in the most of cases. Next, we compared the levels of these cytokine mRNA among the three subgroups of AA that were categorized based on the severity of the symptoms: mild, severe and totalis. Although there was no significant difference between any combinations of the subgroups, there was a tendency to increase the levels of IFN-gamma mRNA and to decrease the levels of IL-4 mRNA according to the severity of alopecia. However, the levels of IFN-gamma mRNA in any subgroups were less than those of HC. These results suggest that IFN-gamma is therefore involved in the pathogenesis of AA, although the information from PBMC is limited. In conclusion, AA might be induced by an aberrant expression of IFN-gamma in individuals whose PBMC produce low amounts of IFN-gamma and TGF-beta1. Further analysis is therefore required to investigate the phenotypes of the population in PBMC with or without reference to regulatory T cells.

Suppressor of cytokine signaling 3 (SOCS3) in Th2 cells evokes Th2 cytokines, IgE, and eosinophilia

Atopic dermatitis, allergic rhinitis, and bronchial asthma are allergic immune disorders characterized by a predominance of T helper 2 (Th2) cells, the resulting elevation of allergen-specific immunoglobulin E (IgE), and mast cell- and eosinophil-associated inflammation. The cytokine environment at the site of the initial antigen stimulation determines the direction of helper T-cell differentiation into Th1 or Th2 cells. Therefore, negative regulators of cytokine signaling, suppressors of cytokine signaling (SOCS) proteins, play an important role in Th2-mediated allergic responses through the control of the balance between Th1 and Th2 cells. SOCS3 and SOCS5 are predominantly expressed in Th2 and Th1 cells, respectively, and they reciprocally inhibit the Th1 and Th2 differentiation processes. In this article, we discuss the role of SOCS3 and SOCS5 proteins in atopic asthma and allergic conjunctivitis and explore the potential of SOCS proteins as targets for therapeutic strategies in allergic disorders.

Association study of polymorphisms in SOCS family genes with type 1 diabetes mellitus

Suppressors of cytokine signalling (SOCS) proteins play important roles in the negative regulation of cytokine signal. We first searched for polymorphisms in SOCS-1, SOCS-3 and SOCS-5 genes, and examined the association of the polymorphisms with type 1 diabetes (T1D). As a result, we did not find any significant associations between SOCS genes and T1D.

The suppressor of cytokine signaling-3 is upregulated in impaired skin repair: implications for keratinocyte proliferation

In this study, we determined regulation and function of the suppressor of cytokine signaling (SOCS)-3 in acute and impaired murine skin repair. Upon skin injury, SOCS-3 was induced and expressed during the inflammatory phase of repair. SOCS-3 protein expression was localized in a subset of non-proliferating keratinocytes within the developing wound margin epithelia. Growth factors (EGF, transforming growth factor-alpha), nitric oxide (NO), and pro-inflammatory cytokines were inducers of SOCS-3 mRNA and protein expression in cultured human (HaCaT) and primary murine keratinocytes. Stable overexpression of SOCS-3 in HaCaT keratinocytes interfered with cytokine-induced signal transducers and activators of transcription-3 phosphorylation and inhibited serum-stimulated proliferation of the cells. Moreover, overexpression of SOCS-3 led to final differentiation of keratinocytes, which was comparable to the Ca(2+)-induced differentiation process in the cells. Finally, we determined SOCS-3 expression in two models of impaired skin repair: NO-deficient and diabetic wound healing. In line with observations from normal repair and SOCS-3 overexpression experiments, reduced keratinocyte proliferation within atrophied neo-epithelia in both models of impaired healing was associated with a marked increase in SOCS-3-expressing wound keratinocytes. In summary, this study suggests a potential novel function of SOCS-3 in regulating keratinocyte proliferation and differentiation in vitro and during skin repair in vivo.

Overexpression of the suppressor of cytokine signalling 3 (SOCS3) in severe atopic dermatitis

Immunoregulatory conditions in atopic dermatitis (AD) involve both Th1 and Th2, although primarily Th2. The suppressor of cytokine signalling 3 (SOCS3) may mediate Th2 regulatory response through negative regulation of Th1 pathways. We examined SOCS3 expression in skin lesions of patients with severe AD and compared it with that in patients with the Th1 disorder, psoriasis. We assessed SOCS3 expression in skin lesions from seven patients with severe AD and five patients with typical psoriasis, and in skin from three normal subjects, using immunohistochemical staining, in situ hybridization and reverse transcription PCR. Strong SOCS3 expression was found in skin lesions in all patients with AD, but only weak expression in patients with psoriasis and in normal subjects. Overexpression of SOCS3 is prominent in the skin of patients with severe AD and consequently may prove useful for evaluating the severity of AD as a Th2-dominant condition.

Excessive expression of Txk, a member of the Tec family of tyrosine kinases, contributes to excessive Th1 cytokine production by T lymphocytes in patients with Behcet's disease

Excessive Th1 cell function is importantly involved in the pathogenesis of Behcet's disease (BD). We previously found that Txk, a member of the Tec family of tyrosine kinases, acts as a Th1 cell specific transcription factor. To investigate immune aberration in the pathogenesis of BD, we studied the expression of Txk and Th1 cytokines in peripheral blood lymphocytes (PBL) and skin lesions in patients with BD. Cytokine production by the lymphocytes was assessed using ELISA. PBL produced excessive Th1 associated cytokines including IFN-gamma and IL-12 spontaneously and in response to exogenous HSP60-derived peptide stimulation, which was shown to induce proliferation of PBL, in patients with BD. Circulating CD4+ T cells expressed excessive Txk protein. A majority of cells infiltrating into skin lesions expressed IFN-gamma in the BD specimens. IL-12 and IL-18 were also expressed in the mononuclear cell aggregates. Lymphocytes accumulating in the skin lesion expressed higher levels of Txk as compared with atopic dermatitis lesions, a typical Th2 disease. IFN-gamma, IL-18 and Il-12 were detected in the BD skin lesions, which may induce preferential development of Th1 cells in patients with BD. The mononuclear cell aggregates contained Txk expressing cells in such skin lesions. Collectively, Txk expressing Th1 cells and the Th1 associated cytokines may play a critical role in the development of skin lesions in BD.