MMP14 (MT1-MMP) binds tissue inhibitor of metalloproteinases 2 (TIMP2) and has been isolated as a complex from the plasma membrane of HT-1080 cells (Strongin et al. 1995). This complex in turn binds proMMP2 via an interaction of the C-termini of proMMP2 and TIMP2 (Itoh et al. 1998, Butler et al. 1998). Formation of this ternary complex is critical for the subsequent activation of proMMP2.