Host and environmental factors influencing respiratory secretion of pro-wheezing biomarkers in preterm children.

Cytokines are actively secreted by the respiratory mucosa of preterm children and participate in the pathogenesis of wheezing. This study aimed to identify the factors that could potentially influence respiratory secretion of cytokines in these children. A nasopharyngeal aspirate (NPA) was collected from 77 preterm children 1 yr after birth. NPAs from 14 healthy, 1-yr-old term children were collected in parallel. 27 cytokines were measured in the NPAs using a multiplex assay. Multivariate stepwise regression analysis with Bonferroni correction evidenced that the variable [daycare attendance] was associated with higher levels of [monocyte chemoattractant protein-1 (MCP-1), IL-6, vascular endothelial growth factor (VEGF), IL-1β, IL-10, tumor necrosis factor (TNF)-α]; [male sex] with higher levels of (MCP-1, VEGF, and IL-1β); [smokers at home] was associated with higher levels of MCP-1 (p < 0.0013). In turn, [prophylaxis with palivizumab] was associated with lower levels of (IL-6, IL-7) (p < 0.0013). All these mediators participate in the pathogenesis of asthma and recurrent wheezing. Preterm children secreted higher levels of chemokines (interferon-gamma inducible protein-10, macrophage inflammatory protein-1α, Eotaxin, MCP-1), growth factors (platelet-derived growth factor-bb, VEGF, fibroblast growth factor-basic, granulocyte macrophage colony-stimulating factor), Th1 (IL12, interferon-γ), Th2 (IL-9, IL-13), Th17 (IL-6, IL-17) cytokines, and immunomodulatory mediators (IL1RA and granulocyte colony-stimulating factor) than term children. In conclusion, we have identified for the first time a group of individual and environmental factors influencing respiratory secretion of cytokines in preterm children at the long term after birth. To know these factors could help to prevent the instauration of conditions linked to the appearance of chronic respiratory diseases such as wheezing or asthma.