Mechanism: MMP2 is a zinc-dependent enzymes capable of cleaving components of the extracellular matrix, which belongs to the matrix metalloproteinase (MMP) family. It is a gelatinase A, 72kDa type IV collagenase which can hydrolyze gelatin under certain conditions. Gelatin zymography is mainly used for the detection of the gelatinases, MMP-2 and MMP-9 and It is extremely sensitive because levels of 10pg of MMP-2 can already be detected. Briefly, various concentrations of MMP2 (500ng, 125ng, 63ng, 32ng, 16ng) were denatured by SDS loading buffer, electrophoresed through sodium dodecylsulphate-polyacrylamide gel (SDS-PAGE; 10% gels) containing gelatin (1mg/mL) with nonreducing conditions. After renaturation, incubation and CCB-stained, active MMP2 would hydrolyze gelatin nearby, which was indicated by the white binds on the gel. In this experiment we use heat-denatured MMP2 protein as negative control, and blood sample as positive control. Result 1: Gelatin hydrolysis by recombinant human MMP2 was shown in figure 1. MMP2 MMP2 MMP2 MMP2 MMP2 negative positive 500ng 125ng 63ng 32ng 16ng control control 70kd→ Figure 1. Hydrolysis of gelatin by MMP2.