OBJECTIVETo investigate the effect of heat shock factor 1 (HSF1) on airway hyperresponsiveness and airway inflammation in mice with asthma and possible mechanisms.

METHODSA total of 36 mice were randomly divided into four groups: control, asthma, HSF1 small interfering RNA negative control (siHSF1-NC), and siHSF1 intervention (n=9 each). Ovalbumin (OVA) sensitization and challenge were performed to induce asthma in the latter three groups. The mice in the siHSF1-NC and siHSF1 groups were treated with siHSF1-NC and siHSF1, respectively. A spirometer was used to measure airway responsiveness at 24 hours after the last challenge. The direct count method was used to calculate the number of eosinophils. ELISA was used to measure the serum level of OVA-specific IgE and levels of interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-13 (IL-13), and interferon-γ (IFN-γ) in lung tissues and bronchoalveolar lavage fluid (BALF). Quantitative real-time PCR was used to measure the mRNA expression of HSF1 in asthmatic mice. Western blot was used to measure the protein expression of HSF1, high-mobility group box 1 (HMGB1), and phosphorylated c-Jun N-terminal kinase (p-JNK).

RESULTSThe asthma group had significant increases in the mRNA and protein expression of HSF1 compared with the control group (P<0.05). The siHSF1 group had significantly reduced mRNA and protein expression of HSF1 compared with the siHSF1-NC group (P<0.05). The knockdown of HSF1 increased airway wall thickness, airway hyperresponsiveness, OVA-specific IgE content, and the number of eosinophils (P<0.05). Compared with the siHSF1-NC group, the siHSF1 group had significantly increased levels of IL-4, IL-5, and IL-13 and significantly reduced expression of IFN-γ in lung tissues and BALF (P<0.05), as well as significantly increased expression of HMGB1 and p-JNK (P<0.05).

CONCLUSIONSKnockdown of HSF1 aggravates airway hyperresponsiveness and airway inflammation in asthmatic mice, and its possible mechanism may involve the negative regulation of HMGB1 and JNK.

Animals ; Asthma ; etiology ; Bronchial Hyperreactivity ; etiology ; immunology ; Cytokines ; biosynthesis ; DNA-Binding Proteins ; analysis ; physiology ; Eosinophils ; physiology ; Female ; HMGB1 Protein ; analysis ; Heat Shock Transcription Factors ; Immunoglobulin E ; blood ; Mice ; Mice, Inbred BALB C ; Transcription Factors ; analysis ; physiology

OBJECTIVETo investigate the changes in the proportion and function of peripheral CD4(+)LAP(+)regulatory T cells (CD4(+)LAP(+)Treg cells) in children with asthma, as well as the role of CD4(+)LAP(+)Treg cells in the pathogenesis of asthma.

METHODSA total of 75 children who were diagnosed with asthma from March 2014 to September 2015 were enrolled as study subjects, and according to their conditions, they were divided into acute-stage asthma group (40 children) and remission-stage asthma group (35 patients). Another 30 children who underwent physical examination were enrolled as the healthy control group. Flow cytometry was used to determine the percentage of peripheral CD4(+)LAP(+)Treg cells, and [(3)H]-thymidine incorporation assay was performed to analyze the immunosuppression of CD4(+)LAP(+)Treg cells in each group.

RESULTSThe acute-stage asthma group showed significant reductions in the proportion of CD4(+)LAP(+)Treg cells compared with the remission-stage asthma group and the healthy control group (2.0%±1.0% vs 4.1%±2.4%/4.6%±3.0%; P<0.05). The acute-stage asthma group also showed a significant reduction in the immunosuppression rate of CD4(+)LAP(+)Treg cells compared with the remission-stage asthma group and the healthy control group (21%±4% vs 55%±9%/62%±11%; P<0.05).

CONCLUSIONSIn children with asthma, the reduction in the number and inhibitory function of peripheral CD4(+)LAP(+)Treg cells may be involved in the pathogenesis of asthma.

Asthma ; etiology ; immunology ; Child ; Child, Preschool ; Female ; Humans ; Male ; T-Lymphocytes, Regulatory ; immunology

Adult ; Allergens ; immunology ; Animals ; Asthma, Occupational ; diagnosis ; etiology ; Bee Venoms ; immunology ; Bees ; immunology ; Cross Reactions ; Fatty Acids ; immunology ; Female ; Humans

OBJECTIVETo investigate the effect of triggering receptor expressed on myeloid cells 2 (TREM-2) overexpression on airway inflammation and remodeling in mice with asthma.

METHODSA total of 40 BALB/c mice were randomly divided into normal control, asthma, empty vector, and TREM-2 overexpression groups (n=10 each). Ovalbumin (OVA) sensitization and challenge were performed to establish the model of asthma. The mice in the control group were given normal saline, and those in the empty vector and TREM-2 overexpression groups were transfected with adenovirus vector and TREM-2 adenovirus, respectively. RT-PCR and Western blot were used to measure the expression of TREM-2, MMP-2, MMP-9, ADAM33, and ADAM8. Bronchoalveolar lavage fluid (BALF) was collected to perform cell counting and classification. ELISA was used to measure the total serum level of IgE and the levels of cytokines in BALF.

RESULTSCompared with the control group, the asthma group showed significant reductions in the mRNA and protein expression of TREM-2 (P<0.05), a significantly increased level of Th2 cytokine (P<0.05), and significantly increased numbers of total cells and classified cells. Compared with the asthma group, the TREM-2 overexpression group showed a significantly reduced level of Th2 cytokine (P<0.05), a significantly reduced level of IgE (P<0.05), and significantly reduced numbers of total cells and classified cells (P<0.05), as well as significantly downregulated expression of the inflammatory factors and growth factors MMP-2, MMP-9, TGF-β1, ADAM8, and ADAM33 (P<0.05).

CONCLUSIONSTREM-2 overexpression significantly alleviates airway inflammation and airway remodeling in mice with asthma and may become a potential target for the prevention and treatment of childhood asthma.

Airway Remodeling ; Animals ; Asthma ; etiology ; immunology ; Cytokines ; analysis ; Female ; Membrane Glycoproteins ; genetics ; physiology ; Mice ; Mice, Inbred BALB C ; Ovalbumin ; immunology ; RNA, Messenger ; analysis ; Receptors, Immunologic ; genetics ; physiology

OBJECTIVETo evaluate the roles of various cytokines, histone acetyltransferase (HAT) and histone deacetylase (HDAC) in the pathogenesis of bronchial asthma.

METHODSBALB/C mice were randomly assigned to control, untreated asthma, hormone treatment and TSA treatment groups. Bronchial asthma was induced by intraperitoneal injections and atomization inhalation of ovalbumin (OVA) in the asthma, hormone treatment and trichostatin (TSA) treatment groups. The mice in the hormone treatment and TSA treatment groups were administered with dexamethasone 1.0 mg/kg and TSA 1.0 mg/kg respectively by an intraperitoneal injection 30 minutes before challenge of asthma. At 24 hours after the last challenge, IL-4, IL-8 and IFN- levels in serum were measured using ELISA, and activities of HAT and HDAC in peripheral blood mononuclear cells (PBMC) were determined by the enzyme linked immunofluorescence assay.

RESULTSThe serum levels of IL-4 and IL-8 in the untreated asthma group were higher than in the control, hormone treatment and TSA treatment groups (P<0.05). There was no difference in the serum levels of IL-4 and IL-8 among the control, hormone treatment and TSA treatment groups (P>0.05). The activity of HDAC in the untreated asthma group was lower than in the control, hormone treatment and TSA treatment groups (P<0.05). Hormone treatment significantly decreased the activity of HAT compared with the untreated asthma group (P<0.05). There was no difference in the activities of HAT and HDAC among the control, hormone treatment and TSA treatment groups (P>0.05).

CONCLUSIONSThe decreased activity of HDAC leads to an increased secretion of inflammatory factors and thus induces asthma.

Animals ; Asthma ; enzymology ; etiology ; immunology ; Cytokines ; blood ; Histone Acetyltransferases ; physiology ; Histone Deacetylases ; physiology ; Male ; Mice ; Mice, Inbred BALB C ; Th1 Cells ; immunology ; Th2 Cells ; immunology

Diisocyanate (DI) is the most common cause of occupational asthma (OA) in Korea. Mannose-binding lectin (MBL) initiates the lectin complement activation pathway following oxidative stress and plays an important role in the regulation of inflammatory processes. To determine whether there is a genetic association between MBL2 polymorphisms and DI-OA, 99 patients with DI-OA, 99 asymptomatic exposed controls (AECs) and 144 unexposed normal controls were enrolled in this study. Three polymorphisms (-554 G>C, - 431A>C and - 225 G>C) in the MBL2 promoter were genotyped, and serum MBL levels were determined by enzyme-linked immunosorbent assay. Functional variabilities in the promoter polymorphisms were analyzed by a luciferase reporter assay and electrophoretic mobility shift assay (EMSA). A significantly higher frequency of haplotype (ht) 2 [CAG] was noted in the DI-OA group compared with the AEC group (P=0.044). The patients with DI-OA carrying ht2 [CAG] had significantly lower PC20 methacholine levels (P<0.001) than the non-carriers. The serum MBL levels were significantly higher in the DI-exposed subjects (both the DI-OA patients and AECs) carrying ht1 [GAG] (P=0.028). Luciferase activity was significantly enhanced in ht1 [GAG] compared with ht2 [CAG] in human hepatocarcinoma cells (Hep3B) (P=0.002). The EMSA showed that a - 554G probe produced a specific shifted band compared with the - 554C probe. These findings suggest that decreased serum MBL levels due to polymorphisms of the MBL2 gene may increase susceptibility to the development of DI-OA in DI-exposed individuals.
Adult ; Alleles ; Asthma, Occupational/diagnosis/*etiology ; Cell Line ; Female ; Forced Expiratory Volume ; Gene Frequency ; Genotype ; Haplotypes ; Humans ; Immunoglobulin E/immunology ; Immunoglobulin G/immunology ; Isocyanates/*adverse effects/immunology ; Male ; Mannose-Binding Lectin/blood/*genetics ; Middle Aged ; *Polymorphism, Genetic ; Polymorphism, Single Nucleotide ; Protein Binding ; Transcriptional Activation ; Young Adult

OBJECTIVEThe prevalence of allergic asthma has been rising continually which is correlated with the increasingly closed living environment. House dust mites are the major sources of indoor aeroallergens which induce asthma in sensitized people. To monitor the seasonal variation of house dust mite (HDM)-allergens exposure level in the asthmatic children, which was evaluated to show its correlation with the level of asthma control, HDM allergic sensitization and fraction of exhaled nitric oxide, and to provide basic data for HDM environmental control.

METHODA total of 48 HDM-allergic asthmatic children were enrolled from the asthma clinic in the hospital from March 2011 to January 2012 (boys 34 and girls 14, aging from 3 to 14 years, mean age 8 years and 4 months) in the present study. Dust samples from mattresses, pillows, bedroom floor, living room floor and sofas were collected in each season within one year in the household of all the enrolled patients. The concentrations of Der p 1 and Der f 1 were measured by the enzyme-linked immunosorbent assay (ELISA). To record the Asthma Control Test (ACT) score or Children Asthma Control Test (C-ACT) score for each patient and to collect the data of doctor monitoring asthma control level each time when the patient was clinic visited. The concentration and its classification of the serum specific IgE to HDM was determined by fluoroenzyme-immunometric assay.

RESULTThe average concentration of Der f 1 of all dust samples was significantly higher than that of Der p 1 (0.13 µg/g vs 0.02 µg/g, P < 0.05). The concentrations of Der f 1 from mattresses, pillows and sofas dust samples were significantly higher than those from bedroom floor and living room floor dust samples (0.69 µg/g, 0.42 µg/g and 0.22 µg/g vs 0.07 µg/g and 0.07 µg/g, P < 0.05). The Der f 1 exposure level from mattress dusts in summer but no others was negatively correlated with asthma control level (r = -0.318, P = 0.036). The Der f 1 exposure level from any area dusts in summer and the Der p 1 exposure level from pillows dusts in autumn was negatively correlated with ACT/C-ACT score respectively. The Der f 1 from mattress dusts in winter was positively correlated with classification of sIgE to Der f 1. The Der p 1 exposure level from most areas in each season was positively correlated with classification of sIgE to Der f 1 and Der P 1.

CONCLUSIONDer f 1 was the predominant mite allergen in household dust and mainly came from mattresses, pillows and sofas. The role of the HDM allergen exposure level on the asthma control level and HDM allergic sensitization for the asthmatic children were depended on its area, season and HDM species, which suggested that the future assessment of clinical effect by the HDM environmental control should consider these factors.

Adolescent ; Air Pollution, Indoor ; adverse effects ; Animals ; Antigens, Dermatophagoides ; analysis ; Asthma ; diagnosis ; etiology ; immunology ; Child ; Child, Preschool ; Dust ; Environmental Exposure ; Enzyme-Linked Immunosorbent Assay ; Female ; Forced Expiratory Volume ; Humans ; Immunoglobulin E ; blood ; Male ; Pyroglyphidae ; immunology ; Risk Factors ; Seasons

OBJECTIVETo study the roles of CD4(+)CD25(+)Foxp3(+) regulatory T cells (Treg) and IL-33 in the pathogenesis of asthma in children.

METHODSFlow cytometry was used to detect peripheral blood CD4(+)CD25(+)Foxp3(+)Treg proportion in CD4(+)T lymphocytes in.45 children with asthma, 50 children with wheezing caused by respiratory syncytial virus infection and 40 healthy children. Serum levels of IFN-γ, IL-4, IL-5 and IL-33 were measured using ELISA.

RESULTSThe level of peripheral blood CD4(+)CD25(+)Foxp3(+)Treg in the asthma group was significantly lower than in the wheezing and control groups (P<0.05). In contrast, serum levels of IL-33 in the asthma group was significantly higher than in the wheezing and control groups (P<0.05). Peripheral blood CD4(+)CD25(+)Foxp3(+)Treg level was negatively correlated with serum IL-33 level in the asthma group(r=-0.156, P<0.01).

CONCLUSIONSCD4(+)CD25(+)Foxp3(+)Treg may interact with IL-33 in the pathogenesis of childhood asthma.

Asthma ; etiology ; immunology ; Child ; Child, Preschool ; Female ; Forkhead Transcription Factors ; analysis ; Humans ; Infant ; Interleukin-2 Receptor alpha Subunit ; immunology ; Interleukin-33 ; Interleukins ; physiology ; Male ; T-Lymphocytes, Regulatory ; physiology

OBJECTIVETo investigate the effect of Mycoplasma pneumoniae (MP) infection on the function of T lymphocytes in the bronchoalveolar lavage fluid (BALF) of asthmatic children in acute and stable periods and the relationship between MP infection and asthma.

METHODSSeventy-one hospitalized children (with bronchitis, pneumonia, and asthma) were divided into non-MP infection control group (group A, pneumonia and bronchitis without MP infection), non-MP infection asthma group (group B), and MP infection asthma group (group C). Flow cytometry was used to determine CD3(+), CD4(+), and CD8(+) T cell counts and CD4(+)/CD8(+) ratio in BALF among all children in acute and stable periods.

RESULTSCompared with group A, groups B and C showed significant differences in CD3(+), CD4(+), and CD8(+) T cell counts and CD4(+)/CD8(+) ratio (P<0.05) in acute and stable periods, had decreased CD3(+) and CD4(+) T cell counts, an increased CD8(+) T cell count, and a significantly decreased CD4(+)/CD8(+) ratio (P<0.05) in the acute period, and had decreased CD3(+) and CD4(+) T cell counts and CD4(+)/CD8(+) ratio and an increased CD8(+) T cell count (P<0.05) in the stable period. Compared with group B, group C had significantly decreased CD3(+) and CD4(+) T cell counts and CD4(+)/CD8(+) ratio (P<0.05) and a significantly increased CD8(+) T cell count (P<0.05) in the acute period and showed no significant differences in CD3(+), CD4(+), and CD8(+) T cell counts (P>0.05) and a significant decrease in CD4(+)/CD8(+) ratio (P<0.05) in the stable period.

CONCLUSIONSThe immunological function of T lymphocytes in the airway declines significantly among asthmatic children with MP infection in acute and stable periods, leading to immue system disorder. MP may be associated with the pathogenesis of asthma.

Asthma ; etiology ; immunology ; Bronchoalveolar Lavage Fluid ; immunology ; CD4-CD8 Ratio ; Child ; Child, Preschool ; Female ; Humans ; Male ; Pneumonia, Mycoplasma ; complications ; immunology ; T-Lymphocytes ; immunology

BACKGROUNDThe hygiene hypothesis has been proposed to explain the pathogenesis of asthma. Allergen exposure was shown to inhibit asthma in an animal model. But the optimal timing of allergen exposure remains unclear. This study aims to explore the time effcct of allergen exposure and the possible mechanisms.

METHODSNeonate Wistar rats were randomly divided into asthma group, control group and day 1, day 3, day 7, and day 14 groups. The day 1, day 3, day 7 and day 14 groups were injected with ovalbumin (OVA) subcutaneously on days 1, 3, 7 and 14 after birth, respectively. Six weeks later, all groups, except the control group, were sensitized and stimulated with OVA to make the asthma model. We observed the pulmonary pathologic changes, detected the regulatory T cells, and CD28 expression level in thymus and spleen by flow cytometry.

RESULTSThe asthmatic inflammation in the day 1, day 3 and day 7 groups, but not the day 14 group, was alleviated. The asthma group and day 14 group had lower proportions of regulatory T cells in the thymus compared with the control group, day 1, day 3, and day 7 groups. There was no significant difference in the CD28 expression levels on the regulatory and conventional T cells among groups. But the control group and the day 1, day 3, and day 7 groups had relatively higher proportions of CD28 positive regulatory T cells in the thymus than the day 14 group and the asthma group.

CONCLUSIONSThere is a "time-window" for early allergen exposure. The impairment of regulatory T cells may promote the development of asthma. Allergen exposure in the "time-window" can make the thymus produce normal quantity of regulatory cells. The CD28 signal on regulatory T cells may participate in the production of regulatory T cells.

Allergens ; immunology ; Animals ; Asthma ; etiology ; CD28 Antigens ; analysis ; physiology ; Disease Models, Animal ; Female ; Ovalbumin ; immunology ; Rats ; Rats, Wistar ; Signal Transduction