Flow-induced endothelial cell alignment requires the RhoGEF Trio as a scaffold protein to polarize active Rac1 distribution
Molecular Biology of the Cell
Endothelial cells line the lumen of the vessel wall and are exposed to flow. In linear parts of the vessel, the endothelial cells experience laminar flow, resulting in endothelial cell alignment in the direction of flow, thereby protecting the vessel wall from inflammation and permeability.  Read more

Huntington's Disease iPSC-Derived Brain Microvascular Endothelial Cells Reveal WNT-Mediated Angiogenic and Blood-Brain Barrier Deficits
Cell Reports
This was a collaboration or Dritan Agalliu, Columbia University and Leslie Thompson, University of California, Irvine, an expert in Huntington's disease. While BBB dysfunction exists in neurological disorders, including Huntington's disease (HD), it is not known if BMECs themselves are functionally compromised to promote BBB dysfunction. Further, the underlying mechanisms of BBB dysfunction remain elusive given limitations with mouse models and post-mortem tissue to identify primary deficits. In this study, the authors undertook a transcriptome and functional analysis of human induced pluripotent stem cell (iPSC)-derived BMECs (iBMEC) from HD patients or unaffected controls. They demonstrate that HD iBMECs have intrinsic abnormalities in angiogenesis and barrier properties, as well as in signaling pathways governing these processes. Thus, their findings provide an iPSC-derived BBB model for a neurodegenerative disease and demonstrate autonomous neurovascular deficits that may underlie HD pathology with implications for therapeutics and drug delivery. This paper will pave the way for our understanding of how BBB dysfunction is mediated in other neurological disorders such as Alzheimer's disease using an iPSC-based approach to generate brain endothelial cells  Read more

A single nucleotide polymorphism of cyclin-dependent kinase inhibitor 1B (p27Kip1) associated with human vein graft failure affects growth of human venous adventitial cells but not smooth muscle cells
Journal of Vascular Surgery
BACKGROUND: Cyclin-dependent kinase inhibitor 1B (p27Kip1) is a cell-cycle inhibitor whose -838C>A single nucleotide polymorphism (rs36228499; hereafter called p27 SNP) has been associated with the clinical failure of peripheral vein grafts, but the functional effects of this SNP have not been demonstrated.  Read more

Tissue Myeloid Progenitors Differentiate into Pericytes through TGF-β Signaling in Developing Skin Vasculature
Cell Reports
Mural cells (pericytes and vascular smooth muscle cells) are essential for the regulation of vascular networks and maintenance of vascular integrity, but their origins are diverse in different tissues and not known in the organs that arise from the ectoderm, such as skin.  Read more

Endothelial Myocyte Enhancer Factor 2c Inhibits Migration of Smooth Muscle Cells Through Fenestrations in the Internal Elastic Lamina
Arteriosclerosis, Thrombosis, and Vascular Biology
OBJECTIVE: Laminar flow activates myocyte enhancer factor 2 (MEF2) transcription factors in vitro to induce expression of atheroprotective genes in the endothelium. Here we sought to establish the role of Mef2c in the vascular endothelium in vivo.  Read more

Host non-inflammatory neutrophils mediate the engraftment of bioengineered vascular networks
Nature Biomedical Engineering
Notwithstanding the remarkable progress in vascular network engineering, implanted bioengineered microvessels mostly fail to form anastomoses with the host vasculature.  Read more