A novel approach to reduce catheter-related infection using sustained-release basic fibroblast growth factor for tissue regeneration in mice

Catheter-related infection is one of the most serious complications. Microbes migrate along the catheter (the foreign material) from the wound at the insertion-site, leading to catheter-related infection. Basic fibroblast growth factor (bFGF) is a potent mitogen that promotes the growth and regeneration of organs and tissues in vivo. Catheter-related bacterial invasion was simulated by the invasion of inoculated bacteria into a transplanted foreign material. Sterile Dacron sheets (foreign materials) were implanted on the subcutis of 96 male mice (C57BL/6) randomized into four groups (n = 24 per group). Group A: Dacron sheets only; Group B: Dacron sheets treated with a plain gelatin hydrogel sheet; Group C: Dacron sheets treated with free bFGF (50 mu g); Group D: Dacron sheets treated with sustained-release bFGF (50 mu g). On day 7, "detachment test" (to measure the force needed to pull out the Dacron sheet) and microscopic evaluations were performed, and the tissue immediately above the Dacron sheet was inoculated with methicillin-resistant Staphylococcus aureus (MRSA) 1 x 10(6) colony-forming units. The total energy needed for pulling out the implanted Dacron sheet in Group D was significantly higher than other three groups (P < 0.01). Group D had a large granulation tissue area containing a large amount of collagen tissue and vessels microscopically. Two days after the MRSA inoculation, the number of MRSA in the Dacron sheet of Group D was smallest. Pretreatment with sustained-release form of bFGF promoted tissue regeneration and reduced catheter-related bacterial invasion, indicating a useful adjuvant for reducing catheter-related infection.