The antiangiogenic activity of the PEDF mutants tested with an extensive bFGF-induced neovascularization. (A) CD-1 nude mice were subcutaneously injected with 0.5 mL Matrigel containing PBS and the various PEDF mutants (all at 20 nM), in the presence or absence of bFGF (500 ng/mL). Control plugs were treated with PBS or bFGF only. After 7 days, mice were killed and the plugs were excised, fixed, sectioned, and stained. Representative fields of H&E staining of thin sections were taken using a light microscope as described for Figure 5. (B) Angiogenesis was quantified by counting the number of infiltrating cells or blood vessels/field for 3 different cross-sectional areas and presented as a mean ± SD (n = 4). Student t test was used to analyze statistical significance of the differences between bFGF- and EEE-treated plugs and plugs treated with bFGF and EEA or the S24,114E mutants (**P < .05).