Effect of fibrinogen, FGF-2, and FGF-2 mutants on new vessel formation in the chicken CAM model. Filter discs soaked in PBS (A), fibrinogen (FBG) (B), FGF-2 (C), non-fibrinogen-binding FGF-2 mutant 2212 (D), fibrinogen-binding FGF-2 mutant 221^*2 (E), 2212 plus FBG (F), 221^*2 plus FBG (G), and wtFGF-2 plus FBG (H). FGF-2 (200 ng/disc) and FBG (20 μg/disc) in a total volume of 20 μL were applied on 8-day-old CAMs. After 72 hours of incubation at 37°C, filters were removed, and each CAM was fixed and photographed. A CAM with a filter disc containing PBS without growth factors was used as control. Bar represents 100 μm. Right column: Quantitation of new vessel formation in the chicken CAM model. The number of new vessels and branches (top) and the average length of new vessels (bottom) were quantified using image analysis software. Seven embryos in each group were used. Data represent mean ± SE.