Perfusion seeding of collagen–chitosan sponges for dermal tissue engineering

Collagen-based sponges have long been used as scaffolds for dermal tissue engineering. However, little study has been done for the investigation of fibroblasts seeding onto these scaffolds. We have characterized, for the first time, the seeding of human dermal fibroblasts onto the collagen–chitosan sponges using a flow perfusion system. It was found that seeding at the perfusion rate of 0.125 ml/min and 0.25 ml/min could achieve significantly higher seeding efficiencies than that at 0.5 ml/min. By comparison with the static seeding method, the perfusion seeding at 0.25 ml/min promoted more efficient cell utilization and achieved higher initial cell densities without compromising the uniformity of initial cell distribution. The uniform distribution of cells achieved from perfusion seeding was found to be favorable to prolong cell proliferation period, increase the number of cells, and form more homogenous morphology of constructed tissues with less contraction. These observations may be helpful to the design of bioreactor systems for in vitro dermal construction.