ORMDL3 is an ER-localized protein (2) expressed in multiple cell types important to the pathogenesis of asthma, including immune and inflammatory cells [i.e., CD4+ cells (3, 4), eosinophils (5), and macrophages (2)] and lung structural cells [i.e., epithelial cells (2) and airway smooth muscle (ASM) (6)]. Here, CD4 is linked to asthma.