An effective method of isolating microvascular endothelial cells from the human dermis

Abstract

Dermal microvascular endothelial cells (DMECs) play central roles in inflammation and angiogenesis and have become important cell models for studying various skin diseases. However, primary DMECs are difficult to culture and often contaminated by mesenchymal stem cells, fibroblasts, and other stromal cells. Surgically removed superfluous foreskin was first cut into pieces, digested with two types of enzymes, and dispersed into single cells. Cells obtained from the dermis were then subjected to Percoll density gradient centrifugation and cells located between densities 1.033 and 1.047 g/ml were further purified with endothelial growth medium containing decreasing concentrations of puromycin. Obtained HDMECs were identified by microscopy, flow cytometry, quantitative reverse-transcription polymerase chain reaction, western blot analysis, and immunofluorescent staining. The expression of CD31 (PECAM-1), CD34, VEGFR2, VWF (Von Willebrand Factor), VE-Cadherin (CD144), and NOS was positive. HDMECs were found to have abilities of angiogenesis and uptake of acetylated low-density lipoprotein. Growth curves and cell viability were analyzed, and a growth pattern consisting of the "latency phase-logarithmic growth phase-stagnation phase" was determined. In this study, a simple, rapid, effective, and low-cost method is established to isolate HDMECs from the foreskin with a purity of over 91% and high viability. The method showed good repeatability and allowed a stable passage. This study provides technical support and theoretical guidance for studying the physiological characteristics of HDMECs, the pathogenesis of the skin associated, and other microvascular diseases.

Keywords: acetylated low-density lipoprotein; angiogenesis; human dermal microvascular endothelial cells; isolation; purification; puromycin.