Moderated Poster session - Vascular26Identification of CMTM3 as a new pro-angiogenic factor essential for vessel stabilization27Regulation of pulmonary vascular PW1+ progenitor cells recruitment during early chronic hypoxia-induced vessel neomuscularization28Impaired interleukin-10 production in response to CpG and depletion of the regulatory CD19+CD24hiCD38hi B cell compartment in patients with coronary atherosclerosis29Inflammatory effects of serum amyloid A via TLR2 and TLR4 in vascular …
Authors: I Chrifi, F Dierick, I E Dumitriu, M Schuchardt, E Jover, Z Yan, R D Fontijn, L Borges, MM Brandt, C Cheng, DJGM Duncker, V Monceau, B Hoareau, N Mougenot, G Marazzi, D Sassoon, JS Hulot, F Soubrier, S Nadaud, P Baruah, S Dinkla, J Bullenkamp, JC Kaski, Y Tu, N Pruefer, M Toelle, S Chebli, W Zidek, M Van Der Giet, A Silvente, F Marin, C Rodriguez, J Martinez-Gonzalez, CM Puche, M Valdes, D Hernandez Romero, J Tan, L Yang, ET Valent, TA Leyen, R Szulcek, JM Baggen, D Geerts, GP Van Nieuw Amerongen, AJG Horrevoets, LAA Alvarenga, RSP Falcao, RR Dias, S Lacchini, PS Gutierrez, JB Michel
Journal: Cardiovascular Research (2016)

Introduction: Interactions between vascular endothelial cells (ECs) and perivascular cells (like vascular smooth muscle cells and pericytes) are essential in the regulation of vascular remodelling and stabilization.Defects in the molecular signalling during ECs-pericytes interaction can lead to deregulated growth of the vasculature which subsequently contribute to cardiovascular disease (CVD).Purpose: Therefore we focus on unravelling molecular pathways which are involved in ECs-pericytes interaction.Methods and Results: Based on a genome-wide microarray screen of human umbilical vein endothelial cells (HUVECs) co-cultured with pericytes, we identified CKLF-like MARVEL transmembrane domain containing 3 (CMTM3) as a new target gene involved in ECs-pericytes interaction.In coculture CMTM3 was significantly upregulated in HUVECs compared to single cultured HUVECs.To evaluate the function of CMTM3 in in vitro neo-vessel formation and stabilization, a 3D collagenbased co-culture of HUVECs and pericytes was conducted.In this co-culture model, knockdown of CMTM3 in HUVECs with short interference RNA (siCMTM3) significantly reduced endothelial tubule and junction formation.In vivo, morpholino-based-silencing of CMTM3 in zebrafish larvae led to defects in sprouting of intersegmental vessels from the dorsal aorta.To assess whether the reduced vascular growth in vitro and in vivo is due to defects in migration of the sprouting ECs, a transwell migration assay was performed on HUVECs.A dramatic decrease in migration of HUVECs was observed in the siCMTM3 treated group compared to control conditions.Furthermore, using immunohistochemistry and western blot we assessed the cell-cell adherence junctions in HUVECs, in which CMTM3 was suppressed with siRNA or overexpressed with adenovirus (adCMTM3).VEcadherin expression was decreased in the siCMTM3 HUVECs and increased in the adCMTM3 treated HUVECs.Interestingly, VE-cadherin was accumulating in the cytoplasm of adCMTM3 treated HU-VECs.Moreover intracellular staining showed a co-localization of CMTM3 with VE-cadherin and with the early endosome markers, Clathrin and Early Endosome Antigen 1. Conclusion: These findings indicate that CMTM3, which is upregulated in ECs after direct contact with pericytes, plays a pro-angiogenic role both in vitro and in vivo, potentially due to its involvement in endothelial migration.Furthermore, CMTM3 is involved in VE-cadherin synthesis and distribution, a key molecule in vascular stabilization, involved in the regulation of ECs barrier function.