Inhibition of cyclin-dependent kinase 4/6 attenuates airway remodeling in a murine severe asthma model by suppressing group 2 innate lymphoid cells proliferation. (PubMed, J Pharmacol Exp Ther)
Using an ovalbumin (OVA)-induced mouse model of severe asthma, we demonstrated that (1) CDK4+ and CDK6+ cells were elevated by 4.0- and 4.5-fold, respectively, in the lungs; (2) treatment with the CDK4/6 inhibitor palbociclib reduced fibrosis and ILC2 expansion by 77% and 87%, respectively; (3) increased ILC2s in the lungs showed high gene expression levels of CDK4, CDK6, and profibrotic factors, including fibroblast growth factor 2, fibroblast growth factor 23, collagen (COL) 4A2, COL10A1, and COL18A1; (4) thymic stromal lymphopoietin stimulation enhanced CDK4/6 protein expression in ILC2s, leading to their proliferation; and (5) palbociclib significantly inhibited the proliferation of ILC2s, at least in part by suppressing retinoblastoma phosphorylation...SIGNIFICANCE STATEMENT: Although cell cycle regulators have been implicated in immune cell proliferation, their role in group 2 innate lymphoid cell-driven asthma pathogenesis remains unexplored. Here, we identified the cyclin-dependent kinase 4/6-group 2 innate lymphoid cell axis as a previously unrecognized driver of airway remodeling in severe asthma.