Asthma is a chronic inflammatory disease of the airway involving various cellular players. Among the different phenotypes of asthma, neutrophilic asthma is often associated with severe airway inflammation and a notable resistance to corticosteroid treatment. Macrophages, as innate immune cells, play a crucial role in the pathogenesis of neutrophilic asthma. They regulate neutrophil recruitment and activation to promote the progression of airway inflammation. During this process, macrophages also undergo changes in aspects such as efferocytosis. We reviewed the recent research progresses regarding the role of macrophages in the pathogenesis of neutrophilic asthma, aiming to provide valuable insights for future studies in this area.
Humans ; Asthma/pathology* ; Neutrophils/pathology* ; Macrophages/immunology* ; Animals ; Phagocytosis

Animals ; Asthma/pathology* ; CD4-Positive T-Lymphocytes/immunology* ; China/epidemiology* ; Disease Models, Animal ; Immunoglobulin E/blood* ; Incidence ; Lung/pathology* ; Mice ; Pollen/chemistry* ; Populus/adverse effects* ; Prevalence

OBJECTIVETo study the dynamic changes in the percentage of Th17 cells/CD4CD25regulatory T cells after intervention with montelukast sodium, a leukotriene receptor antagonist, in asthmatic mice and the association between them.

METHODSBalb/c mice were randomly divided into blank group, asthma group, and montelukast sodium group. The asthmatic mouse model of airway remodeling was established by sensitization with intraperitoneal injection of chicken ovalbumin (OVA) and aluminum hydroxide suspension and aerosol inhalation of OVA. The mice in the blank group were given normal saline, and those in the montelukast sodium group were given montelukast sodium by gavage before aerosol inhalation. Eight mice were randomly sacrificed within 24 hours after 2, 4, and 8 weeks of aerosol inhalation. The pathological sections of lung tissue were used to observe the degree of airway remodeling. Flow cytometry was used to measure the percentages of Th17 cells and CD4CD25regulatory T cells in CD4T cells.

RESULTSThe asthma group and the montelukast sodium group had significantly higher bronchial wall thickness and smooth muscle thickness at all time points compared with the blank group (P<0.05). At 8 weeks of intervention, the montelukast sodium group had significantly greater improvements in the above changes compared with the asthma group (P<0.05). Compared with the blank group, the asthma group and the montelukast sodium group had significant increases in Th17 cells (positively correlated with airway remodeling) and significant reductions in CD4CD25regulatory T cells (negatively correlated to airway remodeling) at all time points (P<0.05). At 8 weeks of intervention, the montelukast sodium group had a significant reduction in the number of Th17 cells and a significant increase in the number of CD4CD25regulatory T cells compared with the asthma group (P<0.05).

CONCLUSIONSMontelukast sodium intervention can alleviate airway remodeling and achieve better improvements over the time of intervention. The possible mechanism may be related to the improvement of immunologic derangement of CD4CD25regulatory T cells and inhibition of airway inflammation.

Acetates ; pharmacology ; Airway Remodeling ; drug effects ; Animals ; Asthma ; drug therapy ; immunology ; Female ; Lung ; pathology ; Mice ; Mice, Inbred BALB C ; Quinolines ; pharmacology ; T-Lymphocytes, Regulatory ; immunology ; Th17 Cells ; immunology

BACKGROUND/AIMS: Role of autophagy in neutrophil function and the association of autophagy and autophagy related (ATG) gene polymorphisms with asthma susceptibility were suggested. In this study, we investigated the genetic association of ATG5 and ATG7 polymorphisms with asthma risk, severity and neutrophilic airway inflammation. METHODS: We recruited 408 asthma patients and 201 healthy controls. Sputum neutrophil counts were determined by H&E staining. Serum interleukin 8 (IL-8) levels were measured by enzyme-linked immunosorbent assay (ELISA). Genetic polymorphisms of ATG5 (-769T>C, -335G>A, and 8830C>T) and ATG7 (-100A>G and 25108G>C) were genotyped. The functional activities of ATG5 -769T>C and -335G>A variants were investigated by luciferase reporter assays. RESULTS: No associations of ATG5 and ATG7 polymorphisms with asthma susceptibility and severity were found. ATG5 -769T>C and -335G>A were in complete linkage disequilibrium. In the asthma group, GA/AA genotypes at ATG5 -335G>A were associated with higher neutrophil counts in sputum (p < 0.05); CC/TT genotype at ATG5 8830C>T associated with lower FEV1% predicted value (p < 0.05). DNA fragments containing ATG5 -769T and -335G alleles had higher promoter activities compared to those with -769C and -335A in both human airway epithelial cells (A549, p < 0.01) and human mast cell (HMC-1, p < 0.001). GG and CC genotype at ATG7 -100A>G and 25108G>C were significantly associated with high serum levels of IL-8 (p < 0.05 for both variants). CONCLUSIONS: Genetic polymorphisms of ATG5 and ATG7 could contribute to neutrophilic airway inflammation in the pathogenesis of adult asthma.
Adolescent ; Adult ; Asthma/blood/*genetics/immunology/pathology ; Autophagy/*genetics ; Autophagy-Related Protein 5/*genetics ; Autophagy-Related Protein 7/*genetics ; Case-Control Studies ; Cell Line ; Female ; Gene Frequency ; Genes, Reporter ; Genetic Predisposition to Disease ; Haplotypes ; Heterozygote ; Homozygote ; Humans ; Interleukin-8/blood ; Male ; Middle Aged ; Neutrophil Infiltration/*genetics ; Neutrophils/immunology/metabolism/*pathology ; Phenotype ; *Polymorphism, Single Nucleotide ; Promoter Regions, Genetic ; Risk Factors ; Severity of Illness Index ; Transfection ; Young Adult

OBJECTIVETo study the dynamic changes in Th17 cells and CD4⁺ CD25⁺ regulatory T cells (Treg) in the spleen and to analyze their relationship with airway remodeling.

METHODSA total of 48 female specific pathogen-free Balb/c mice were randomly divided into control and asthmatic groups. To establish the asthmatic airway remodeling model, the mice were sensitized to ovalbumin (OVA) through intraperitoneal injection of OVA and aluminum hydroxide suspension and challenged by inhalation of aerosol OVA. The matched control group was treated with normal saline instead. In 24 hours after 2-week, 4-week, and 8-week aerosol inhalation, 8 mice were randomly selected from each group and sacrificed. Then histopathological examination of the left lung was performed to measure the degree of airway remodeling. The percentages of Th17 and CD4⁺ CD25⁺ Treg cells in total CD4(+) cells from the spleen were determined by flow cytometry.

RESULTSIn the asthmatic group, the ratios of total bronchial wall area to bronchial basement membrane perimeter (WAt/Pbm) and bronchial smooth muscle area to bronchial basement membrane perimeter (WAm/Pbm) significantly increased as the challenge proceeds (P<0.01). The percentage of Th17 cells derived from the cell suspension of the spleen gradually increased and it was positively correlated with the degree of asthmatic airway remodeling (P<0.01). The percentage of CD4⁺ CD25⁺ Treg cells from the suspension gradually decreased and it was negatively correlated with the degree of asthmatic airway remodeling (P<0.01).

CONCLUSIONSIn mice with asthma, as the challenge proceeds, the airway remodeling becomes more severe, the percentage of Th17 cells increases, and the percentage of CD4⁺ CD25⁺ Treg cells decreases. The immunological imbalance is possibly one of the important factors inducing airway remodeling.

Airway Remodeling ; Animals ; Asthma ; immunology ; pathology ; Disease Models, Animal ; Female ; Lung ; pathology ; Mice ; Mice, Inbred BALB C ; T-Lymphocytes, Regulatory ; immunology ; Th17 Cells ; immunology

OBJECTIVETo study the correlation between airway inflammation and osteopontin (OPN) level in the lung tissue, and to study the effect of dexamethasone (DXM) on OPN expression.

METHODSFifty mice were randomly divided into 5 groups: normal control, ovalbumin (OVA)-challenged asthma groups (OVA inhalation for 1 week or 2 weeks) and DXM-treated asthma groups (DXM treatment for 1 week or 2 weeks). The mice were sensitized and challenged with OVA to prepare mouse model of acute asthma. Alterations of airway inflammation were observed by haematoxylin-eosin staining. Serum level of OVA-sIgE was evaluated using ELISA. OPN expression in the lung tissue was located and measured by immunohistochemistry and Western blot respectively. OPN mRNA level in the lung tissue was detected by real-time PCR.

RESULTSThe asthma groups showed more pathological changes in the airway than the normal control and the DXM-treated groups. Compared with the OVA-challenged 1 week group, the pathological alterations increased in the OVA-challenged 2 weeks group. The level of OVA-sIgE in serum increased in the asthma groups compared with the control and the DXM groups (P<0.01). Serum OVA-sIgE sevel increased more significantly in the OVA-challenged 2 weeks group compared with the OVA-challenged 1 week group (P<0.01). OPN protein and mRNA levels were significantly raised in the asthma groups compared with the normal control and the DXM groups (P<0.01), and both levels increased more significantly in the OVA-challenged 2 weeks group compared with the OVA-challenged 1 week group (P<0.01).

CONCLUSIONSThe increased OPN expression in the lung tissue is associated with more severe airway inflammation in asthmatic mice, suggesting that OPN may play an important role in the pathogenesis of asthma. DXM can alleviate airway inflammation possibly by inhibiting OPN production.

Animals ; Asthma ; drug therapy ; metabolism ; pathology ; Dexamethasone ; therapeutic use ; Enzyme-Linked Immunosorbent Assay ; Female ; Immunoglobulin E ; blood ; Lung ; metabolism ; pathology ; Mice ; Mice, Inbred BALB C ; Osteopontin ; analysis ; genetics ; physiology ; Ovalbumin ; immunology

OBJECTIVETo study the effects of suplatast tosilate (IPD) on the airway inflammation and expression of interleukin-5 in asthmatic rats.

METHODSFifty adult male Sprague-Dawley rats (4-week- old) were randomly assigned to five groups: placebo control, untreated asthma, budesonide(BUD)-treated asthma , early or late IPD intervention group (n=10 rats each). Asthmatic mode was prepared by ovalbumin sensitizion and challenge. Inflammatory cells and the percentage of EOS were detected in bronchoalveolar lavage fluid (BALF). The lung tissues were removed to detect the lung histomorphology. Gene expression of IL-5 was measured by reverse transcription-polymerase chain reaction (RT-PCR). Levels of interleukin 5 (IL-5) in BALF were measured using ELISA.

RESULTSThe inflammatory cells and the percentage of EOS in BALF, IL-5 levels in BALF and IL-5 mRNA expression in the lung tissues were obviously higher in the untreated asthma group than the control group (P<0.05), while the parameters in the IPD or BUD-treated asthma groups were significantly lower than the untreated asthma group (P<0.05).

CONCLUSIONSIPD treatment can alleviate airway inflammation in asthmatic rats, possibly through inhibiting IL-5 mRNA transcripts.

Animals ; Arylsulfonates ; therapeutic use ; Asthma ; drug therapy ; immunology ; pathology ; Eosinophils ; drug effects ; Interleukin-5 ; analysis ; antagonists & inhibitors ; genetics ; Lung ; metabolism ; pathology ; Male ; Rats ; Rats, Sprague-Dawley ; Sulfonium Compounds ; therapeutic use

OBJECTIVETo investigate the changes in the levels of interleukin-17 (IL-17) and transforming growth factor beta 1 (TGF-β1) in serum and bronchoalveolar lavage fluid (BALF) and their clinical significance among children with asthma.

METHODSFifty-six children with asthma were divided into moderate or severe asthma (n=37) and mild asthma groups (n=19) and 18 children without asthma were selected as the control group. Cells in BALF were counted under a microscope. The levels of IL-17 and TGF-β1 in serum and BALF were measured using ELISA.

RESULTSwere no significant differences in total cell count and percentage of macrophages between the two asthma groups and the control group (P>0.05). The percentages of neutrophils, eosinophils and epithelial cells in BALF were significantly higher in the two asthma groups than in the control group (P<0.05). The two asthma groups had significantly higher levels of IL-17 and TGF-β1 in serum and BALF than the control group (P<0.05), and the moderate or severe asthma group had significantly higher levels of IL-17 and TGF-β1 in serum and BALF than the mild asthma group (P<0.05). Levels of IL-17 and TGF-β1 in serum were significantly positively correlated with those in BALF (r=0.935 and 0.943, P<0.05 for both). In children with asthma, serum IL-17 level was significantly positively correlated with the percentage of neutrophils, eosinophils and epithelial cells in BALF (r=0.802, 0.799, and 0.674, P<0.05 for all), and a significant positive correlation was also seen between serum levels of IL-17 and TGF-β1 (r=0.878, P<0.05).

CONCLUSIONSLevels of IL-17 and TGF-β1 in serum and BALF are elevated in children with asthma. IL-17 and TGF-β1 may be involved in the occurrence and development of asthma, and they play important roles in asthma attack and aggravation.

Asthma ; immunology ; pathology ; Bronchoalveolar Lavage Fluid ; chemistry ; cytology ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Interleukin-17 ; analysis ; blood ; physiology ; Male ; Transforming Growth Factor beta1 ; analysis ; blood ; physiology

OBJECTIVETo investigate the activation of Toll like receptor 4 (TLR4) on passively sensitized human airway smooth muscle cells (HASMCs) proliferation and the synthesis and secretion function.

METHODSThrough the cultivation of primary HASMCs, we studied TLR4 expression on cell surface, cell proliferation and transformation of parturient factor-beta1 (TGF-beta1) in asthma under the condition of synthesis and secretion level by passively sensitized HASMCs with asthma serum.

RESULTSCompared with the control group, in passive sensitized group and TNF-alpha group TLR4 expression were significantly increased (P < 0.01), significantly enhanced proliferation (P < 0.01), total protein concentration, IgE secretion and TGF-beta1 were significantly higher (P < 0.01); and all the above parameters were increased more significantly in TNF group compared with those in the target effect of passively group; and those parameters were significantly reduced in anti-TLR4 antibody group compared with those in the target effect both of passively sensitized group and TNF-alpha group.

CONCLUSIONTLR4 on passively sensitized HASMCs activated can induce the excessive proliferation of HASMCs and a large number of synthesis and secretion of TGF-beta1, resulting in changing airway micro-environment, which involved in airway remodeling in asthma.

Airway Remodeling ; Asthma ; metabolism ; pathology ; Bronchi ; cytology ; Cell Proliferation ; Cells, Cultured ; Humans ; Myocytes, Smooth Muscle ; cytology ; metabolism ; Toll-Like Receptor 4 ; immunology ; Transforming Growth Factor beta1 ; metabolism

AIM: To evaluate the effect of Qi'ao Deocoction (QAD) on the inflammation and hyperresponsiveness of asthma mice. METHODS: 120 Balb/C mice were randomly divided into six groups: normal group, model group, dexamethasone group, high dose QAD group, medium dose QAD group and low dose QAD group. The asthma model was reproduced in Balb/C mice sensitized by ovalbumin, challenged by OVA and LPS. The mice of the normal group were sensitized, challenged and intranasally instilled by PBS. On day 28-34, 6.7, 13.4 and 26.8 g · kg(-1) Qi'ao Decoction were administrated; 0.002 4 g · kg(-1) dexamethasone solution was given to the dexamethasone group; normal and model groups were given the same amount of normal saline. Bronchoalveolar lavage fluid, airway hyperresponsiveness, lung histopathology and cytokines were then collected and analyzed. RESULTS: Compared with normal group, total cellular score, the number of macrophages, lymphocytes, eosinophils and neutrophils of model group significantly increased (P < 0.01). Compared with model group, the administration of dexamethasone induced a significant decrease in eosinophils and neutrophils (P < 0.05, P < 0.01). The number of eosinophils, which plays an important role in airway inflammatory reaction of asthma, of the three QAD groups all decreased (P < 0.01). RL before and after Ach (5 mg · mL(-1)) stimulation in the model group both overtook that in the normal group (P < 0.01). Compared with model group, dexamethasone group, high dose QAD group, medium dose QAD group and low dose QAD group groups all had significantly lower RL before and after Ach stimulation (P < 0.01). Normal pulmonary histopathology was found in the normal group. In the model group, mice exhibited marked increases in inflammatory cell infiltration, mostly including neutrophils and macrophages, perivascular inflammation and thickened alveolus wall (P < 0.01). Dexamethasone application mitigated inflammation around the bronchi (P < 0.05). These histopathological changes were ameliorated in the three decoction groups (P < 0.01, P < 0.05). In addition, alveolus and airway wall lesions of medium dose QAD group and high dose QAD group were reduced, the number of inflammatory cells infiltrated around the walls decreased, no clear degeneration of bronchial epithelial cells was found, and exudates in bronchi declined in different degrees. Compared with normal group, IFN-γ and IL-12 of model group significantly decreased, while IL-4 increased, showing statistic difference (P < 0.05). Compared with model group, IFN-γ and IL-12 level of dexamethasone group went up too, but IL-4 declined (P < 0.05). The level of IFN-γ of medium dose QAD group and high dose QAD group both increased; IL-4 and IL-12 of medium dose group were found significant differences (P < 0.05); but none of the cytokines of low dose QAD group showed statistical significance (P > 0.05). CONCLUSION QAD can significantly inhibit airway inflammation and airway hyperresponsiveness of mice with severe asthma induced by ovalumin and lipopolysaccharide, adjust the balance of cytokines, and improve lung histopathological condition. So, it exhibits great effect on severe asthma.
Animals ; Asthma ; chemically induced ; drug therapy ; immunology ; pathology ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Humans ; Interleukin-12 ; immunology ; Interleukin-4 ; immunology ; Lipopolysaccharides ; adverse effects ; immunology ; Lung ; immunology ; pathology ; Mice ; Mice, Inbred BALB C ; Ovalbumin ; adverse effects ; immunology