Figure 8.

Kinetics of macrophage-mediated induction of fibroblast collagenase-3. Murine monocytic J774 cells were allowed to condition medium for 24 h in the presence of zymosan (4 mg/ml). (A) Primary cultures of ALFs were treated with 0–50% zymosan-treated J774-conditioned medium (CM) for 48 h and harvested for Northern blot analysis of collagenase-3 (C’ase) and glyceraldehyde-3-phosphate dehydrogenase (GAP) mRNAs. (B) Primary cultures of ALFs were untreated (−) or treated with 50% zymosan-treated J774-CM (+) for 6–96 h and harvested for Northern blot analysis as above. Medium was changed after 48 h; therefore, 96 h cultures received 48 h of 50% CM followed by either another 48 h of 50% CM (+/+) or 48 h of nonconditioned medium (+/−). (C) Primary cultures of ALFs were untreated (lane 1) or were treated with 50% zymosan-treated J774-CM alone (lane 2) or with 50% zymosan-treated J774-CM in the presence of 10 μg/ml cycloheximide (lane 3). Fibroblasts were also treated with cycloheximide in the absence of CM (lane 4) as a control.