Assessment of full-thickness wounds in the genetically diabetic mouse for suitability as a wound healing model.

While using the diabetic C57BL/KsJ db/db mouse as a wound healing model, we encountered several repair patterns which affect its suitability as a predictive screening model for certain indications. For example, wound contraction, albeit impaired, was found to be particularly dependent on bandaging technique and vehicle type. Wounds which had been continuously occluded with Opsite dressings had a high relative variability in contraction, and there was a tendency toward reduced contraction, suggesting that the dressings were acting as a splint. Viscous dosing vehicles inhibited contraction of occluded wounds but appeared to enhance contraction of nonoccluded wounds. In contrast to many other models, occlusion in these studies did not enhance reepithelialization when compared with air exposure (the rate of reepithelialization in db/db mice appeared normal, typically growing 2 mm from each edge in 10 days). Also in contrast to other wound healing models, viscous dosing vehicles when used under occlusion inhibited reepithelialization. However, as seen in other wound healing models, granulation tissue thickness was reliably increased in response to treatment with recombinant human platelet-derived growth factor-BB. Our experience with the db/db diabetic mouse model has led us to recommend the use of this animal model only after its limitations have been identified and accepted.