MMPs from biological samples are routinely analyzed by zymography, immunoblotting and SDS-PAGE. Although valuable in yielding useful information, each technique has its own limitations. For example, zymography is a sensitive technique for detection of pro and active forms of MMPs in gels. Zymograms do not provide specificity, however, and sources of observed proteinase activities can only be correlated with MMPs of known molecular weight.

R&D Systems' Human MMP-12 Purification Kit is a complete system designed to purify human MMP-12. The entire immunopurification procedure takes approximately 2 hours and yields pure MMP-12 (up to mg quantities). The key component of the kit is the antibody-coated bead that specifically binds to MMP-12. A control antibody bead and a sample containing recombinant human MMP-12 are also included to monitor kit performance. Purified MMP-12 can then be analyzed by additional techniques such as zymography, immunoblotting and protein-staining of SDS-PAGE gels.

Figure 1. Silver staining of a SDS-PAGE gel with samples obtained using the Human MMP-12 Purification Kit, Hemopexin Domain (Catalog # IP920) . Lanes 1 to 6 contain: different amounts of BSA at 0.1, 0.2, 0.5, 0.8, 1.0 and 1.5 µg used to estimate the amount of the purified protein; Lane 7: starting material; Lane 8: unbound material; Lane 9: eluted material. MW markers are indicated on the left. The recovered human MMP-12 forms correspond to proenzyme (55 kDa) and hemopexin-like domain (25 kDa).