Expression of NLRP3 in serum and induced sputum of children with asthma and their relationship with disease severity.

OBJECTIVES

The aim of this cross-sectional study is to investigate the levels of NLRP3 in the serum and induced sputum of children with asthma and their potential association with lung function and disease severity.

METHODS

This cross-sectional study included 83 children with bronchial asthma who sought medical care at our hospital from May 2023 to February 2024. Portable spirometry was used to monitor lung function parameters, including forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow. The expression of C-reactive protein (CRP), interleukin (IL)-6, IL-1β, TNF-α, and Nod-like receptor family pyrin domain-containing 3 (NLRP3) in the serum and induced sputum were measured by enzyme-linked immunosorbent assay. Data analysis was performed using SPSS 25.0 and differences with P < 0.05 were considered statistically significant.

RESULTS

Children with asthma exhibited significantly elevated levels of serum NLRP3, CRP, IL-6, IL-1β, and TNF-α compared to healthy controls. In addition, children with moderate-severe asthma had significantly higher levels of serum and induced sputum NLRP3 and IL-1β compared to children with mild asthma. Spearman's correlation analysis revealed a positive correlation between induced sputum NLRP3 and IL-6. Moreover, induced sputum NLRP3 was negatively correlated with lung function parameters. The results of receiver operating characteristic curves showed that induced sputum NLRP3 could be used for diagnosing children with moderate-severe asthma, with an AUC was 0.758, cutoff value of 3.33 ng/mL, sensitivity of 66.1%, and specificity of 70.8%. Furthermore, the logistic regression analysis revealed that serum and induced sputum NLRP3, induced sputum IL-6 and IL-1β were risk factors for children with moderate-severe asthma.

CONCLUSIONS

In this cross-sectional study, we found a significant increase in NLRP3 levels in induced sputum of children with asthma, which further increased in those with moderate-severe disease. The levels of NLRP3 in induced sputum could serve as potential biomarkers for assessing disease severity.