Figure 6: WT and Timp-1^−/− PMN contain similar amounts of Mmp-8 and Mmp-9 and similar quantities of Mmp-8 and Mmp-9 are released from degranulating WT and Timp-1^−/− PMNs:

Extracts of freshly-isolated unstimulated PMNs from WT and Timp-1^−/− mice and cell-free supernatant fluids from WT and Timp-1^−/− PMN that had been activated with 10⁻⁶ M fMLP for 30 min were immuno-blotted for Mmp-9 (A) or Mmp-8 (B). The arrows indicate the proMMP-9 and proMmp-8 forms of the Mmps. Note that extracts of unstimulated WT and Timp-1^−/− PMNs contain similar amounts of proMmp-9 and proMmp-8 (M_r = 100 kDa for Mmp-9 and 85 kDa for Mmp-8). In addition, when activated with fMLP, Timp-1^−/− PMNs freely release similar amounts of Mmp-8 and Mmp-9 exclusively as the latent proMmp forms.