Characterization of microvascular endothelial cells isolated from the dermis of adult mouse tails.

Dermal microvascular endothelial cells (DMECs) play an important role in physiological and pathophysiological processes such as wound healing, cell differentiation, antigen-presentation, inflammation, tumor metastasis, and diabetes. The study of these processes requires a suitable and accessible in vitro model, such as murine DMECs (mDMECs). However, since these cells are difficult to isolate and propagate, some of their properties are not fully characterized. We isolated these cells from C57BL/6J adult mouse tail skin and purified them using magnetic sorting. Then, we tested several culture conditions and oxygen concentrations for mDMEC growth and propagation. After obtaining optimal culture conditions, we characterized the expression of EC markers and compared such expression with an established murine microvascular EC line (EOMA). Our results indicate that mDMECs isolated from mouse tails expressed most of the characteristic EC markers such as von Willebrand Factor (vWF), CD31, Tie1, Tie2, ANGPT1, ANGPT2, FLK-1, FLT-1, and VEGF-A. Further characterization demonstrated that these cells also expressed proteins involved in organogenesis such as bone morphogenetic proteins-2, -4 (BMP-2/-4), and their receptor (BMPR1A). Surprisingly, higher expression of vWF, ANGPT1, and BMP-2 was observed in mDMECs compared to EOMA cells. For mDMEC in vitro propagation, we found a twofold increase in cell proliferation in cells that grew at 1% O(2) compared to those cells that grew at standard 20% O(2.) Therefore, the method described herein for mDMECs isolation and propagation allowed us to analyze in more detail their biological properties that can be relevant for the study of pathological processes using mouse models.