Improvement of vascular sprouting from OMDs of EC-Smad2/3KO embryos. OMD assay was performed using Smad2fl/fl;Smad3+/−;Tie2-Cre (A-C) and EC-Smad2/3KO OMDs (D-F). (A-D) Infection with adenoviral LacZ. (B-E) Infection with adenoviral Smad3. (C-F) Infection with adenoviral Smad2.