Increased inhibitory surface marker PD-1 expression in CD4+T cells and Th2+T cells in allergen-specific immunotherapy.

Recent evidence has shown that T cell exhaustion is implicated in Allergen-specific Immunotherapy (AIT). However, how T cell exhaustion plays a role in AIT is far from clear. Our study aimed to investigate T cell exhaustion associated with allergen exposure during AIT in mice. Ovalbumin (OVA) - sensitized C57BL/6J asthma mouse and AIT mouse models were constructed. Quantitative real-time PCR (qRTPCR) and flow cytometry were used to monitor the occurrence of local and systemic CD4+ T cells and Th2+T cells exhaustion in OVA-sensitized mice. The inhibitory surface marker programmed cell death protein 1 (PD-1) on CD4+ T cells and Th2+T cells was significantly upregulated in AIT mice compared with asthmatic and control mice. The level of PD-1 on the surface of CD4+T cells of asthma mice was significantly higher than that of control mice. The inhibitory surface marker cytotoxic T lymphocyte-associated protein 4 (CTLA-4) on CD4+ T cells and Th2+T cells showed no significant difference between the AIT, asthma and control mice. Collectively, our study indicated that the expression of PD-1 on CD4+ T cells and Th2+T cells was increased in AIT. Allergen exposure promotes the expression of PD-1 on the surface of CD4+ T cells. T cell exhaustion plays an important role in AIT.

Effect of different inhalant allergens on T-cell subsets in adults with bronchial asthma.

OBJECTIVE: We analyzed the impact of different inhalant allergens on T-lymphocyte subsets in patients diagnosed with bronchial asthma. METHODS: The study included 57 bronchial asthma patients and 22 healthy controls. Asthma patients were categorized into dust mite, animal hair, pollen, and mold groups. Flow cytometry was used to measure the cells in the case group and control group. These T-lymphocyte subset markers were evaluated among patients with bronchial asthma caused by different allergens as well as between the case group and control group. RESULTS: Peripheral blood CD4+ T-cells, CD8+ T-cells, CD4/CD8 ratio, and Th17/Treg ratios were all higher in the case group than in the control group (p < 0.05). Peripheral blood T-lymphocyte subsets were compared among the four groups, and it was found that there were statistical differences in the Th17/Treg ratio among the four groups (p < 0.05). There were no significant differences observed among the four groups in terms of CD3+ cells, CD4+ cells, CD8+ cells, Th1 cells, Th2 cells, Th17 cells, Treg cells, Th9 cells, and Th22 cells. Further pairwise comparison was made, and the results suggested that the peripheral blood Th17/Treg ratio in the pollen mixed group was lower than that in the dust mite mixed group, animal hair mixed group, and mold mixed group (p < 0.05). CONCLUSION: Patients with bronchial asthma show varied T-lymphocyte subset responses to different inhalant allergens. Elevated CD4+ T cells and Th17 cells in peripheral blood could indicate asthma risk. However, small sample size may introduce bias to these findings.

Investigation analysis of the acute asthma risk factor and phenotype based on relational analysis with outdoor air pollutants in Xi'an, China.

Asthma is a common chronic heterogeneous disease. Outdoor air pollutants are an important cause of acute asthma. Until now, the association between the risk of acute asthma and outdoor air pollutants is unclear. And the relationship between the different phenotypes of asthma and outdoor air pollutants has not been reported. Thus, an analysis of the association between outdoor air pollutants and daily acute asthma inpatient and outpatient visits in Xi'an, China, from January 1 to December 31, 2018, was conducted. A total of 3395 people were included in the study. The statistical analysis and relational analysis based on the logistic regression were used for illustrating the relatedness of the acute asthma risk factor and phenotype with outdoor air pollutants, while the age, gender, pollen peak and non-pollen peak periods, high type 2 (T2) asthma and non-high T2 asthma were also stratified. Results showed that particulate matter with particle size below 10 µm and 2.5 µm (PM10 and PM2.5), sulfur dioxide(SO2), nitrogen dioxide(NO2), and carbon monoxide(CO) increase the risk of acute asthma and that air pollutants have a lagged effect on asthma patients. PM10, NO2, CO, and Ozone (O3) are associated with an increased risk of acute attacks of high T2 asthma. PM10, PM2.5, SO2, NO2 and CO are associated with an increased risk of acute asthma in males of 0-16 years old. PM10 and PM2.5 are more harmful to asthma patients with abnormal lung function.

Effects of different inhalant allergens on lung functions in adult patients with bronchial asthma.

OBJECTIVE: To analyze the effects of different types of inhalant allergens on the lung functions of adult patients with bronchial asthma. METHODS: This cross-sectional study included a total of 47 adults diagnosed with bronchial asthma at the Respiratory Outpatient Department of Tianjin First Central Hospital. Patients were divided into non-sensitized and sensitized groups based on the number of positive allergens detected and classified into four groups (the dust mite mixed group, animal dander mixed group, pollen-mixed group, and mold mixed group) based on the type of positive allergen detected. They were tested for the serum concentration of allergen-specific immunoglobulin E (sIgE) using a fluorescence immunoassay analyzer, and lung function was assessed using a pulmonary function testing machine. One-way analysis of variance was used to compare normally distributed data, while the rank sum test was utilized for non-normally distributed data. RESULTS: There was no statistically significant difference in lung function indicators between these two groups (p > .05). There were statistically significant differences in forced expiratory volume in one second as a percentage of the predicted value (FEV1 %pred) (p = .028), FEV1 /forced vital capacity as a percentage of the predicted value; (FVC%pred) (p = .016), peak expiratory flow as a percentage of the predicted value (PEF%pred) (p = .001), forced expiratory flow at 50% of the predicted value of forced vital capacity (FEF50%pred) (p = .003), forced expiratory flow at 75% of the predicted value of forced vital capacity (FEF75%pred) (p = .023), and maximal midexpiratory flow (MM)EF75/25%pred (p = .002) among the four groups. The pollen-mixed group had higher PEF%pred (pollen vs. animal dander, p = .067; pollen vs. dust-mites, p = .008; pollen vs. molds, p = .001) and MMEF75/25%pred (pollen vs. animal dander, p = .048; pollen vs. dust-mites, p = .003; pollen vs. molds, p = .001) than the other three groups. The pollen-mixed group had higher FEF50%pred than the dust-mites mixed group (p = .008) and molds-mixed group (p = .001). The pollen-mixed group had higher FEF75%pred (p = .005), FEV1 %pred (p = .001), and FEV1 /FVC%pred (p = .001) than the molds-mixed group. CONCLUSION: Different inhalant allergens had different effects on lung functions in adults with asthma.

A predictive model for frequent exacerbator phenotype of acute exacerbations of chronic obstructive pulmonary disease.

Background: The frequent exacerbator phenotype of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is characterized by experiencing at least two exacerbations per year, leading to a significant economic burden on healthcare systems worldwide. Although several biomarkers have been shown to be effective in assessing AECOPD severity in recent years, there is a lack of studies on markers to predict the frequent exacerbator phenotype of AECOPD. The current study aimed to develop a new predictive model for the frequent exacerbator phenotype of AECOPD based on rapid, inexpensive, and easily obtained routine markers. Methods: This was a single-center, retrospective study that enrolled a total of 2,236 AECOPD patients. The participants were divided into two groups based on the frequency of exacerbations: infrequent group (n=1,827) and frequent group (n=409). They underwent a complete blood count, as well as blood biochemistry, blood lipid and coagulation testing, and general characteristics were also recorded. Univariate analysis and binary multivariate logistic regression analyses were used to explore independent risk factors for the frequent exacerbator phenotype of AECOPD, which could be used as components of a new predictive model. The receiver operator characteristic (ROC) curve was used to assess the predictive value of the new model, which consisted of all significant risk factors predicting the primary outcome. The nomogram risk prediction model was established using R software. Results: Age, gender, length of stay (LOS), neutrophils, monocytes, eosinophils, direct bilirubin (DBil), gamma-glutamyl transferase (GGT), and the glucose-to-lymphocyte ratio (GLR) were independent risk factors for the frequent exacerbator phenotype of AECOPD. The area under the curve (AUC) of the new predictive model was 0.681 [95% confidence interval (CI): 0.653-0.708], and the sensitivity was 63.6% (95% CI: 58.9-68.2%) and the specificity was 65.0% (95% CI: 60.3-69.6%). Conclusions: A new predictive model based on demographic characteristics and blood parameters can be used to predict the frequency of acute exacerbations in the management of chronic obstructive pulmonary disease (COPD).