Blood vessels of the skin are composed of a number of cellular and non-cellular elements. The predominant cell type in all skin blood vessels is the endothelial cells. Endothelial cells form the interface between intravascular and extravascular compartments and serve as a selective barrier for the diffusion of cells and macromolecules between these two compartments. While endothelial cells lining blood vessels of the skin share features of endothelial cells elsewhere in the body, they also exhibit several skin specific characteristics. They actively participate in a variety of physiological processes including wound healing, control of hemostasis, temperature regulation, and modulation of inflammation/leukocyte trafficking. Via signaling pathways controlling cell proliferation, quiescence, apoptosis, and senescence, endothelial lining of blood vessels shows remarkable phenotypic and functional heterogeneity, which in turn allows the cutaneous microvasculature to be set in a dynamic balance between maintenance and remodeling. HDMEC-a from ScienCell Research Laboratories are isolated from human skin. HDMEC-a are cryopreserved at passage one and delivered frozen. Each vial contains >5 x 105 cells in 1 ml volume. HDMEC-a are characterized by immunofluorescence with antibodies specific to vWF/Factor VIII and/or CD31 (PECAM1). HDMEC-a are negative for HIV-1, HBV, HCV, mycoplasma, bacteria, yeast, and fungi. HDMEC-a are guaranteed to further expand for 15 population doublings under the conditions provided by ScienCell Research Laboratories. Recommended Medium It is recommended to use Endothelial Cell Medium (ECM, Cat. #1001) for culturing HDMEC-a in vitro.