Phenotypic characterization of lung macrophages in asthmatic patients: Overexpression of CCL17

This study does not support the existence in human asthma of the full M2 phenotype described to date but points to upregulation of CCL17 in both patients with mild and those with moderate asthma, providing a further source for this ligand of CCR4+ cells that contributes to airways inflammation. CCL17 expression is corticosteroid resistant but suppressed by PI3K enzyme inhibitors.