Figure 3. Alk1-deficient ECs form a more persistent and intricate tube-like network and are resistant to BMP-9.
The same number (1×105) of 2f/1f- and 1f/1f-ECs suspended in chemically defined growth factor- and serum-free ECM containing bFGF (50 ng/ml) and various concentrations of BMP-9 (0, 1, 5, and 20 ng/ml) were seeded onto the Matrigel in 24-well plates. A, B. Representative images of the tube-like network of 2f/1f (A) and 1f/1f (B) pECs at 3, 6, 9, 12, 24, and 48 hrs after plating. C, D. Histogram showing the total tubular lengths of 2f/1f (C) and 1f/1f (D) ECs. Tubular lengths tended to be lower at all time points for 5 and 20 ng/ml of BMP-9 treated 2f/1f-ECs, which reached a statistically significant level at 24 and 48 hours (C), whereas no such a trend was observed in 1f/1f-ECs (D). *P<0.05.