Egm 2 mv complete medium

Human umbilical vein endothelial cells (HUVECs) were obtained from the American Type Culture Collection (ATCC, Manassas, VA, USA). HUVECs were cultured in EGM‐2 MV complete medium (LONZA; Walkersville, MD, USA). When HUVECs reached 50% confluence in 24‐well dishes, the cells were starved in serum‐free endothelial cell growth medium 2. After starvation, cells were incubated with DPSC‐CM and 3‐(4,5‐di‐methylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT; Sigma). After a 2‐h incubation, HUVECs were lysed, and the absorbance at 550 nm was read using a spectrophotometer (Spark; TECAN, Männedorf, Switzerland).
Another cell proliferation assay was carried out using a Cell Counting Kit‐8 (CCK‐8; Dojindo, Kumamoto, Japan) according to the manufacturer's procedure. After starvation, cells were incubated with DPSC‐CM and CCK‐8 for 2 h. For each well, the absorbance at 450 nm was read on a spectrophotometer.

Human umbilical vein endothelial cells (HUVEC) were purchased from Cell Applications, cultured in EGM-2MV complete medium (Lonza) or Medium 200 + LSGS (Gibco, Waltham, MA, USA) on a gelatin-coated surface and used at passage 4. To produce a conditioned medium containing ApoExo, cells were exposed to RPMI serum-free medium (Gibco) for 4 h to induce apoptosis in endothelial cells. Serum starvation is a classical inducer of apoptosis. We showed previously that serum starvation in endothelial cells increases chromatin condensation in the absence of cell membrane permeabilization along with caspase-3 activation^{11 (link)–13 (link)}.