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Blood eosinophils can be described as inflammatory-like (iEOS-like) and lung-resident-like (rEOS-like) eosinophils. This study is based on the hypothesis that eosinophilopoetins such as interleukin (IL)-3 and IL-5 and granulocyte-macrophage colony-stimulating factor (GM-CSF) alter the proliferative properties of eosinophil subtypes and may be associated with the expression of their receptors on eosinophils. We investigated 8 individuals with severe nonallergic eosinophilic asthma (SNEA), 17 nonsevere allergic asthma (AA), and 11 healthy subjects (HS). For AA patients, a bronchial allergen challenge with Dermatophagoides pteronyssinus was performed. Eosinophils were isolated from peripheral blood using high-density centrifugation and magnetic separation methods. The subtyping of eosinophils was based on magnetic bead-conjugated antibodies against L-selectin. Preactivation by eosinophilopoetins was performed by incubating eosinophil subtypes with IL-3, IL-5, and GM-CSF, and individual combined cell cultures were prepared with airway smooth muscle (ASM) cells. ASM cell proliferation was assessed using an Alamar blue assay. The gene expression of eosinophilopoetin receptors was analyzed with a qPCR. IL-5 and GM-CSF significantly enhanced the proliferative properties of iEOS-like and rEOS-like cells on ASM cells in both SNEA and AA groups compared with eosinophils not activated by cytokines (p < 0.05). Moreover, rEOS-like cells demonstrated a higher gene expression of the IL-3 and IL-5 receptors compared with iEOS-like cells in the SNEA and AA groups (p < 0.05). In conclusion: IL-5 and GM-CSF promote the proliferative properties of iEOS-like and rEOS-like eosinophils; however, the effect of only IL-5 may be related to the expression of its receptors in asthma patients.

Enhanced contractility and migration of airway smooth muscle cells (ASMC) and pulmonary fibroblasts (PF) are part of airway remodeling in asthma. Eosinophils are the central inflammatory cells that participate in airway inflammation. However, the role of asthmatic eosinophils in ASMC and PF contractility, migration, and differentiation to contractile phenotype has not yet been precisely described. A total of 38 individuals were included in this study: 13 steroid-free non-severe allergic asthma (AA) patients, 11 severe non-allergic eosinophilic asthma (SNEA) patients, and 14 healthy subjects (HS). For AA patients and HS groups, a bronchial allergen challenge with D. pteronyssinus was performed. Individual combined cell cultures were prepared from isolated peripheral blood eosinophils and immortalized ASMC or commercial PF cell lines separately. The migration of ASMC and PF was evaluated using wound healing assay and contractility using collagen gel assay. Gene expression of contractile apparatus proteins, COL1A1, COL5A1, and FN, in ASMC and PF was evaluated using qRT-PCR. We found that contractility and migration of ASMC and PF significantly increased after incubation with asthmatic eosinophils compared to HS eosinophils, p < 0.05, and SNEA eosinophils demonstrated the highest effect on contractility of ASMC and migration of both cell lines, p < 0.05. AA and SNEA eosinophils significantly increased gene expression of contractile apparatus proteins, COL1A1 and FN, in both cell lines, p < 0.05. Furthermore, the allergen-activated AA eosinophils significantly increased the contractility of ASMC, and migration and gene expression in ASMC and PF, p < 0.05. Thus, asthmatic eosinophils change ASMC and PF behavior by increasing their contractility and migration, contributing to airway remodeling.