Ozonated oil alleviates dinitrochlorobenzene-induced allergic contact dermatitis via inhibiting the FcεRI/Syk signaling pathway / 中南大学学报(医学版)

OBJECTIVES@#Ozone is widely applied to treat allergic skin diseases such as eczema, atopic dermatitis, and contact dermatitis. However, the specific mechanism remains unclear. This study aims to investigate the effects of ozonated oil on treating 2,4-dinitrochlorobenzene (DNCB)-induced allergic contact dermatitis (ACD) and the underling mechanisms.@*METHODS@#Besides the blank control (Ctrl) group, all other mice were treated with DNCB to establish an ACD-like mouse model and were randomized into following groups: a model group, a basal oil group, an ozonated oil group, a FcεRI-overexpressed plasmid (FcεRI-OE) group, and a FcεRI empty plasmid (FcεRI-NC) group. The basal oil group and the ozonated oil group were treated with basal oil and ozonated oil, respectively. The FcεRI-OE group and the FcεRI-NC group were intradermally injected 25 µg FcεRI overexpression plasmid and 25 µg FcεRI empty plasmid when treating with ozonated oil, respectively. We recorded skin lesions daily and used reflectance confocal microscope (RCM) to evaluate thickness and inflammatory changes of skin lesions. Hematoxylin-eosin (HE) staining, real-time PCR, RNA-sequencing (RNA-seq), and immunohistochemistry were performed to detct and analyze the skin lesions.@*RESULTS@#Ozonated oil significantly alleviated DNCB-induced ACD-like dermatitis and reduced the expressions of IFN-γ, IL-17A, IL-1β, TNF-α, and other related inflammatory factors (all P<0.05). RNA-seq analysis revealed that ozonated oil significantly inhibited the activation of the DNCB-induced FcεRI/Syk signaling pathway, confirmed by real-time PCR and immunohistochemistry (all P<0.05). Compared with the ozonated oil group and the FcεRI-NC group, the mRNA expression levels of IFN-γ, IL-17A, IL-1β, IL-6, TNF-α, and other inflammatory genes in the FcεRI-OE group were significantly increased (all P<0.05), and the mRNA and protein expression levels of FcεRI and Syk were significantly elevated in the FcεRI-OE group as well (all P<0.05).@*CONCLUSIONS@#Ozonated oil significantly improves ACD-like dermatitis and alleviated DNCB-induced ACD-like dermatitis via inhibiting the FcεRI/Syk signaling pathway.

Antibody to FcεRIα Suppresses Immunoglobulin E Binding to High-Affinity Receptor I in Allergic Inflammation

PURPOSE: High-affinity receptor I (FcεRI) on mast cells and basophils plays a key role in the immunoglobulin E (IgE)-mediated type I hypersensitivity mediated by allergen cross-linking of the specific IgE-FcεRI complex. Thus, prevention of IgE binding to FcεRI on these cells is an effective therapy for allergic disease. We have developed a strategy to disrupt IgE binding to FcεRI using an antibody targeting FcεRIα. MATERIALS AND METHODS: Fab fragment antibodies, which lack the Fc domain, with high affinity and specificity for FcεRIα and effective inhibitory activity against IgE-FcεRI binding were screened. IgE-induced histamine, β-hexosaminidase and Ca2+ release in basophils were determined by ELISA. A B6.Cg-Fcer1a(tm1Knt) Tg(FCER1A)1Bhk/J mouse model of passive cutaneous anaphylaxis (PCA) was used to examine the inhibitory effect of NPB311 on allergic skin inflammation. RESULTS: NPB311 exhibited high affinity to human FcεRIα (KD=4 nM) and inhibited histamine, β-hexosaminidase and Ca2+ release in a concentration-dependent manner in hFcεRI-expressing cells. In hFcεRIα-expressing mice, dye leakage was higher in the PCA group than in controls, but decreased after NPB311 treatment. NPB311 could form a complex with FcεRIα and inhibit the release of inflammation mediators. CONCLUSION: Our approach for producing anti-FcεRIα Fab fragment antibody NPB311 may enable clinical application to a therapeutic pathway in IgE/FcεRI-mediated diseases.

Antibody to FcεRIα Suppresses Immunoglobulin E Binding to High-Affinity Receptor I in Allergic Inflammation

PURPOSE: High-affinity receptor I (FcεRI) on mast cells and basophils plays a key role in the immunoglobulin E (IgE)-mediated type I hypersensitivity mediated by allergen cross-linking of the specific IgE-FcεRI complex. Thus, prevention of IgE binding to FcεRI on these cells is an effective therapy for allergic disease. We have developed a strategy to disrupt IgE binding to FcεRI using an antibody targeting FcεRIα. MATERIALS AND METHODS: Fab fragment antibodies, which lack the Fc domain, with high affinity and specificity for FcεRIα and effective inhibitory activity against IgE-FcεRI binding were screened. IgE-induced histamine, β-hexosaminidase and Ca2+ release in basophils were determined by ELISA. A B6.Cg-Fcer1a(tm1Knt) Tg(FCER1A)1Bhk/J mouse model of passive cutaneous anaphylaxis (PCA) was used to examine the inhibitory effect of NPB311 on allergic skin inflammation. RESULTS: NPB311 exhibited high affinity to human FcεRIα (KD=4 nM) and inhibited histamine, β-hexosaminidase and Ca2+ release in a concentration-dependent manner in hFcεRI-expressing cells. In hFcεRIα-expressing mice, dye leakage was higher in the PCA group than in controls, but decreased after NPB311 treatment. NPB311 could form a complex with FcεRIα and inhibit the release of inflammation mediators. CONCLUSION: Our approach for producing anti-FcεRIα Fab fragment antibody NPB311 may enable clinical application to a therapeutic pathway in IgE/FcεRI-mediated diseases.

The correlations of FcεRI-βgene polymorphisms with clinical manifestations and prognosis inwheezing infants / 实用医学杂志

Objective To investigate the correlations of FcεRI-βgene polymorphisms with clinical manifestation and prognosis inwheezing infants. Methods One hundred and forty-six wheezing infants were recruited and divided into two groups by FcεRI-βdetection using Fluorescent quantitative PCR: Risk genotype group (n = 41) or normal genotype group (n = 105). The genotype distributions,clinical manifestation and asthma,and morbidity were analyzed and compared between the two groups. Results FcεR1 E237G AG/GG was more serious than FcεR1 AA in wheezing infants. (χ2 = 14.202; P = 0.003). No significant differences were found in AS morbidity between the two groups after two years follow-up (χ2 = 2.25;P = 0.13). Conclusion FcεRI-βgene polymorphisms are strongly related with infantile wheezing. Th risk genotype may be the severity of asthma but may not be the major influencing factor of asthma.

Influence of B lymphocyte stimulator on the production of anti-FcεRI and anti-IgE antibodies by B lymphocytes from patients with chronic idiopathic urticaria / 中华皮肤科杂志

Objective To explore if B lymphocyte stimulator (BlyS) stimulates B lymphocytes from patients with chronic idiopathic urticaria (CIU) to produce anti-high affinity IgE receptor (FcεRI) or anti-IgE antibodies.Methods Totally,300 CIU patients and 300 health controls were enrolled in this study.Blood samples were obtained from these subjects.Peripheral blood B lymphocytes were isolated and cultured in vitro for 72 hours.Then,BlyS of various concentrations (2,4,8,16 ng/ml) was added to the culture medium of B lymphocytes followed by another 72-hour culture.Enzyme-linked immunosorbent assay was performed to determine the serum levels of BlyS,anti-FcεRI and anti-IgE antibodies,as well as the supernatant levels of anti-FcεRI and anti-IgE antibodies.The relationship between BlyS and anti-FcεRI and anti-IgE antibody production was assessed.SPSS software version 16.0 was used for statistical analysis.Chi-square test was performed to compare the positivity rate of antibodies,and analysis of variance and least significance difference-t test to assess numerical data.Results The CIU patients showed higher levels of serum BlyS (t =3.04,P ＜ 0.01),anti-FcεRI antibodies (t =3.51,P ＜ 0.01),and anti-IgE antibodies (t =3.29,P ＜ 0.01) compared with the health controls.The serum level of BlyS was positively correlated with that of anti-FcεRI antibodies (r =0.93,P ＜ 0.01) and anti-IgE antibodies (r =0.91,P ＜ 0.01).The levels of anti-FcεRI antibodies and anti-IgE antibodies were significantly increased in the culture supematant of patient-derived B lymphocytes treated with BlyS compared with those remaining untreated (t =3.67,3.56,respectively,both P ＜ 0.01),and the concentration of BlyS was positively correlated with the levels of both anti-FcεRI antibodies and anti-IgE antibodies (r =0.96,0.91,respectively,both P ＜ 0.01).The coincidence rate between the serum and supernatant was 94.76％ and 87.84％ in the detection of anti-FcεRI antibodies and anti-IgE antibodies respectively.Conclusions BlyS level is upregulated in the serum of patients with CIU,which may play an important role in the pathogenesis of CIU by stimulating B lymphocytes to produce anti-FcεRI antibodies or anti-IgE antibodies.

A revisit to cockroach allergens.

Among cockroaches (CR) that live in people’shomes, two species, i.e., German CR (Blattella germanica) and American CR (Periplaneta americana) predominate in temperate and tropical areas, respectively. CR is an important source of inhalant indoor allergens that sensitize atopic subjects to (localized) type I hypersensitivity or atopy including allergic rhinitis and atopic asthma. In Thailand the predominant CR species is P. americana. CR allergens are found throughout CR infested houses; the number found in kitchens correlates with the degree of CR infestation while sensitization and reactivation of the allergic morbidity are likely to occur in the living room and bedroom. Levels of the CR allergens in homes of CR allergic Thais, measured by using locally made quantification test kits, revealed that the highest levels occur in dust samples collected from the wooden houses of urban slums and in the cool and dry season. CR allergens are proteins that may be derived from any anatomical part of the insect at any developmental stage. The allergens may be also from CR secretions, excretions, body washes or frass. The proteins may be the insect structural proteins, enzymes or hormones. They may exist as dimers/multimers and/or in different isoforms. Exposure to CR allergens in infancy leads to allergic morbidity later in life. Clinical symptoms of CR allergy are usually more severe and prolonged than those caused by other indoor allergens. The mechanisms of acute and chronic airway inflammation and airway hyper-responsiveness (AHR) have been addressed including specific IgE- and non-IgEmediated mechanisms, i.e., role of proteaseactivated receptor-2 (PAR2). Participation of various allergen activated-CD4+ T cells of different sublineages, i.e., Th2, Th17, Th22, Th9, Th25, Tregs/Th3 as well as invariant NKT cells, in asthma pathogenesis have been mentioned. The diagnosis of CR allergy and the allergy intervention by CR population control are also discussed.

Polymorphisms of the high-affinity receptor for IgE alpha-chain (FcεRIα) gene in patients with atopic dermatitis / 中华皮肤科杂志

Objective To assess the relationship between single nucleotide polymorphisms of FcεRIαgene and atopic dermatitis. Methods Genomic DNA samples were extracted from peripheral blood of 97 patients with atopic dermatitis and 283 normal human controls. The polymorphism at the distal promoter region of FcεRIα gene was determined by PCR-ligase detection reaction assay followed by gene sequencing. Results A G/T polymorphism was observed at position rs61828219 in the promoter region of FcεRIα gene, while all the tested individuals were homozygous for T/T at position rs12135235 and A/A at position rs36233780 in the promoter region of FcεRIα gene. The mutation frequency at position rs61828219 was 1.04% and 2.17% in patients with AD and normal human controls, respectively (both P ＞ 0.05). Conclusions In the Chinese Han population, there is a G/T polymorphism at position rs61828219 in FcεRIα gene promoter region, which is unlikely related to the development of AD; however, no polymorphism is detected at position rs12135235 or rs36233780.