title: Mutual interaction between endothelial cells and mural cells enhances BMP9 signaling in endothelial cells.
abstract: Hereditary hemorrhagic telangiectasia is characterized by the formation of abnormal vascular networks and caused by the mutation of genes involved in BMP9 signaling. It is also known that the interaction between endothelial cells (ECs) and mural cells (MCs) is critical to maintain vessel integrity. However, it has not yet fully been uncovered whether the EC-MC interaction affects BMP9 signaling or not. To elucidate this point, we analyzed BMP9 signaling in a co-culture of several types of human primary culture ECs and MCs. The co-culture activated the Notch pathway in both types of cells in a co-culture- and BMP9-dependent manner. In HUVECs, the genes induced by BMP9 were significantly and synergistically induced in the presence of pericytes, fibroblasts or mesenchymal stem cells. The synergistic induction was greatly reduced in a non-contact condition. In fibroblasts, PDGFRB expression was potently induced in the presence of HUVECs, and BMP9 additively increased this response. Taken together, these results suggest that the EC-MC interaction potentiates BMP9 signaling both in ECs and MCs and plays a critical role in the maintenance of proper vessel functions.
authors.affiliation: Pain and Neuroscience Laboratories, R&D Division, Daiichi Sankyo Co., Ltd., Tokyo 140-8710, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Tachida
authors.affiliation: End-Organ Disease Laboratories, R&D Division, Daiichi Sankyo Co., Ltd., Tokyo 140-8710, Japan.
authors.forename: Nanae
authors.initials: N
authors.lastname: Izumi
authors.affiliation: Hit Discovery and Cell Processing Research Group Biological Research Department, Daiichi Sankyo RD Novare Co., Ltd., Tokyo 134-8630, Japan.
authors.forename: Toyo
authors.initials: T
authors.lastname: Sakurai
authors.affiliation: Pain and Neuroscience Laboratories, R&D Division, Daiichi Sankyo Co., Ltd., Tokyo 140-8710, Japan kobayashi.hideki.gc@daiichisankyo.co.jp.
authors.forename: Hideki
authors.identifier: http://orcid.org/0000-0002-3650-9154
authors.initials: H
authors.lastname: Kobayashi
keywords: BMP9; Cell–cell interaction; HHT; Mural cells; Vascular integrity