Endogro

Passage 1 (P1) ASCs and low-serum medium (MesenPRO RS™) were purchased from a supplier (Invitrogen, Carlsbad, CA, USA). Cells were cultured as monolayers in 75-cm² vented tissue culture flasks (BD Biosciences, Franklin Lakes, NJ, USA) at 37°C, 5% CO₂, and 95% air in a well-humidified environment (hereafter referred to as, 20% oxygen conditions). Upon reaching 80–90% confluence, the cells were trypsinized (Corning Life Sciences, Manassas, VA, USA) and counted by hemacytometer (Hausser Scientific, Horsham, PA, USA) then used for study or reseeded for continued expansion. In order to ensure consistent cell behavior, cells between P2 and P5 were used in all studies, according to the supplier's recommendations.
P1 HUVECs (Millipore, Billerica, MA, USA) were cultured as monolayers in a high-growth expansion medium containing VEGF (EndoGRO™; EMD Millipore, Billerica, MA, USA) in 20% oxygen. At 80–90% confluence, the cells were trypsinized (EMD Millipore) and counted, then used for study or reseeded for culture expansion. In certain experiments, a low-serum, VEGF-free medium (hereafter, LS medium; EMD Millipore) was used as a negative control, and LS medium supplemented with 2 ng/ml human recombinant VEGF (VEGF₁₆₅, Invitrogen; hereafter, VEGF medium) was used as a positive control. To ensure consistent cell behavior, HUVECs between P2 and P5 were used for study.