MMP-7 degrades human recombinant sVEGFR-1 but not VEGF. (A) Human recombinant sVEGFR-1 was incubated with MMP-7 in the presence or absence of the MMP inhibitor EDTA. The digestion products were analyzed by SDS-PAGE and silver staining. ▶ indicates the full-length recombinant sVEGFR-1 (96 kDa). (B) Human recombinant sVEGFR-1 was incubated with MMP-7, -2, or -9 and analyzed by SDS-PAGE and Western blotting. sVEGFR-1 was detected by an antibody directed against the extracellular region of VEGFR-1, which shares identical extracellular domains with sVEGFR-1. ▶ indicates full-length recombinant sVEGFR-1. (C) Human recombinant VEGF₁₆₅ was incubated with MMP-7 in the presence or absence of EDTA and analyzed by SDS-PAGE and Western blotting. (D) Human recombinant sVEGFR-1 was incubated with MMP-7 at different times and analyzed by SDS-PAGE and silver staining. ▶ indicates the full-length recombinant sVEGFR-1.