Purpose: This study examined the effects of locally administered TGF-b and PDGF via a time-release mechanism on an incisional cyclophosphamide-impaired healing model. A porous drug delivery system (DDS) impregnated with growth factors was developed for this study.

Methods: The rat dorsal skin incision was utilized. DDS alone or DDS impregnated with TGF-b, PDGF, or both delivered 50ng of the experimental agent/day. Following wounding, on postoperative days 1, 3, and 5, the rats received injection of 48mcg/kg of cyclophosphamide. Each group was evaluated on post-wounding days 4,7 and 14 for wound breaking strength.

Results: The average wound breaking strengths for each group are demonstrated graphically along with standard deviations. When final wound breaking strength values were compared with Student’s t-test, the wound breaking strength for the combination of TGF-b and PDGF was significantly different from BSA(p=0.03), TGF-b alone(p=0.01) and PDGF alone(p=0.01).

Conclusion: The use of a porous drug delivery system to administer TGF-b and PDGF in combination in an impaired model of rat dorsal incisional wound healing increases the wound breaking strength. The use of either TGF-b or PDGF alone did not result in a significant increase in average wound breaking strength.