Cardiac microvascular endothelial cells (CMEC) play important roles in myocardial function. CMEC regulate vascular tone by releasing and degrading endothelium-derived vasoactive factors, and modulating the local levels of vasoconstrictors and vasodilators through their enzymatic activities. Many of these substances can also modify myocardial contractile behavior. Furthermore, microvasculature has been shown to participate in the regulation of leukocyte recruitment, inflammation, and angiogenesis. They are also capable of trans-differentiating into myofibroblasts, suggesting a role in aberrant accumulation of matrix and fibrotic disorders. CMEC cultures provide an invaluable tool for understanding CMEC physiological and pathophysiological relevance in cardiac function and disease. HCMEC from ScienCell Research Laboratories are isolated from human heart. HCMEC are cryopreserved at passage one and delivered frozen. Each vial contains >5 x 105 cells in 1 ml volume. HCMEC are characterized by immunofluorescence with antibodies specific to vWF/Factor VIII and/or CD31 (PECAM1). HCMEC are negative for HIV-1, HBV, HCV, mycoplasma, bacteria, yeast, and fungi. HCMEC are guaranteed to further expand for 5 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 HCMEC in vitro.