DIVAA analysis of purified recombinant CD97 proteins. (A) Angioreactors were prepared as described and recovered after 9 days.30 Shown are angioreactors containing Matrigel and either the mFc backbone protein, bFGF, E/1-5-RGD-FL (100 ng/mL), or E/1-5-RGE-FL (100 ng/mL). The corners at the open end of the angioreactors are marked, and arrows indicate the depth of invasion by new vessel formation. Image acquisition was performed as described elsewhere.30 (B) DIVAA was quantitated by intravenous injection of FITC-dextran, killing of the mice after 20 minutes, and recovery of the angioreactors, dispase digestion, and fluorescence spectroscopy. One representative experiment from a total of 3 that were performed is shown. Results are expressed in fluorescence units as the average plus or minus the standard error of the mean (SEM), n = 4. Student t test comparison of results for bFGF versus Matrigel alone and for E/1-5-RGD-FL at 100 ng/mL and 25 ng/mL versus mFc protein was significant (P < .01). The E/1-5-RGE-FL sample was assayed separately from the others and is the average of 4 angioreactors. Florescence units have been normalized to mFc protein (100 ng/mL) performed in the same experiment.
