Expression of M2 macrophages in children with asthma and study of probiotic-assisted treatment to pediatric asthma

Objective To investigate the expression of M2 macrophages in children with asthma and the significance of probiotics in the adjuvant treatment of children with asthma. Methods A total of 90 children with bronchial asthma who were admitted to the Affiliated Hospital of Xuzhou Medical University from January 2023 to June 2023 were selected as an asthma group, and 80 healthy children who underwent physical examination at the same hospital during the same period were selected as a control group. The expression levels of serum arginase-1 (Arg-1) and chemokine (C-C motif) ligand 22 (CCL22) were compared between the two groups. The children with asthma were divided into group A (treated with inhaled budesonide suspension + bifidobacterium) and group B (treated with inhaled budesonide suspension). Both groups were treated for 3 months.The levels of serum interleukin-4 (IL-4), interleukin-13 (IL-13), Arg-1, and CCL22, as well as pulmonary function parameters were compared before and three months after treatment. The number of acute asthma attacks was recorded before treatment and 1 and 3 months after treatment to evaluate the theraputic effectiveness and stability. Results The levels of Arg-1 and CCL22 in the asthma group were higher than those in the control group, the difference was statistically significant (P＜0.05). Three months after treatment, the levels of serum IL-4, IL-13, Arg-1 and CCL22 in groups A and B significantly decreased compared with those before treatment (P＜0.05). Percentage of predicted forced expiratory volume in one second (FEV1%pred), percentage of predicted peak expiratory flow (PEF%pred), and percentage of predicted maximum mid-expiratory (MMEF75/25%pred) increased compared with those before treatment (P＜0.05), with more significant changes observed in Group A (P＜0.05). At the third month of treatment, the number of acute attacks of asthma in both groups decreased compared to before treatment, with group A showing a significantly lower number of acute asthma attacks than Group B at the same time point (P＜0.05). Conclusions M2 macrophages are hyperpolarized and Arg-1 and CCL22 are highly expressed in children with asthma, which may play a role in the development and progression of airway inflammation and remodeling in children with asthma. Probiotics may inhibit the excessive polarization of M2 macrophages to a certain extent, thereby improving pulmonary function and clinical symptoms in children with asthma.