GENERATION AND ACTIVITY OF THE TERNARY GELATINASE-B TIMP-1 LMW-STROMELYSIN-1 COMPLEX

Incubation of progelatinase B, isolated from human polymorphonuclear l eukocytes, with TIMP-1 leads to the formation of the progelatinase B/T IMP-1 complex, This complex behaves like a Janus in a similar manner a s we previously described for the progelatinase A/TIMP-2 complex. It s hows the properties of TIMP-1 and is a better inhibitor for gelatinase A than for gelatinase B. Treatment with trypsin leads to activation o f the binary complex, The activity, however amounts only to slightly m ore than 10% of the activity of free gelatinase B, not complexed with TIMP-1. When the progelatinase B/TIMP-1 complex inhibits an active mat rix metalloproteinase, a ternary complex is generated that after activ ation displays a distinct higher proteolytic activity than the active binary complex, The active binary complex cannot be transformed into t he active ternary complex.