Novel chitosan-based hyaluronan hybrid polymer fibers as a scaffold in ligament tissue engineering.

To clarify the feasibility of using novel chitosan-based hyaluronan hybrid polymer fibers as a scaffold in ligament tissue engineering, their mechanical properties and ability to promote cellular adhesion, proliferation, and extracellular matrix production were studied in vitro. Chitosan fibers and chitosan-based 0.05% and 0.1% hyaluronan hybrid fibers were developed by the wet spinning method. Hyaluronan coating significantly increased mechanical properties, compared to the chitosan fibers. Rabbit fibroblasts adhesion onto hybrid fibers was significantly greater than for the control and chitosan fibers. For analysis of cell proliferation and extracellular matrix production, a three-dimensional scaffold was created by simply piling up each fiber. At 1 day after cultivation, the DNA content in the hybrid scaffolds was higher than that in the chitosan scaffold. Scanning electron microscopy showed that the fibroblasts had produced collagen fibers after 14 days of culture. Immunostaining for type I collagen was clearly predominant in the hybrid scaffolds, and the mRNA level of type I collagen in the hybrid scaffolds were significantly greater than that in the chitosan scaffold. The present study revealed that hyaluronan hybridization with chitosan fibers enhanced fiber mechanical properties and in vitro biological effects on the cultured fibroblasts.