Expression of BMP‐2 in the pulmonary neuroepithelial body microenvironment (869.7)

Abstract

Recently, members of the bone morphogenetic protein (BMP) family, in particular BMP‐2, have been reported to promote adult lung tissue repair after injury. Following severe experimental intrapulmonary airway epithelial damage, the neuroepithelial body (NEB) microenvironment (ME) has been shown to be involved in epithelial regeneration, and today may be regarded as an airway stem cell niche. The NEB ME consists of highly innervated groups of pulmonary neuroepithelial endocrine cells, which are specifically covered by Clara‐like cells with supposed stem cell characteristics.Here we studied the expression of BMP‐2 in the NEB ME of healthy postnatal mouse lungs. After collection of ‘NEB sample’ by selective isolation of GFP‐fluorescent NEBs via laser microdissection from frozen sections of GAD67‐GFP mouse lungs, (q)RT‐PCR revealed a significantly higher expression of BMP‐2 in the NEB ME, compared to control airway epithelium. Localization of the BMP‐2 protein in postnatal mouse lungs by multiple immunofluorescence, revealed that BMP‐2 was expressed by vagal sensory nerve fiber endings that selectively contact NEB cells.The presented data reveal a strong expression of BMP‐2 in the NEB ME and strengthen the suggestion of an important role in postnatal airway epithelial repair after injury.Grants: FWO (G.0589.11), Hercules Foundation (AUAH‐09‐001); UA (GOA BOF 2007)