Different behavior of meniscal cells in collagen II/I,III and Hyaff-11 scaffolds in vitro

The purpose of this study was to evaluate the behavior of ovine meniscal cells seeded on biomaterials made from collagen and hyaluronan, respectively. Ovine meniscal cells were isolated from the medial menisci of stifle joints, expanded in monolayer culture, and seeded on scaffolds made of collagen type II and I/III and a hyaluronan derivative (Hyaff-11). The samples were cultured for 12 h and 7, 14, 21, and 28 days. Histological analysis, electron microscopy, biochemical assays for glycosaminoglycans (GAGs) and DNA, and reverse transcriptase polymerase chain reaction analysis for collagens were performed. The cells attached well to both biomaterials and produced tissue-specific proteins, such as GAG and collagen type I, over a period of 28 days. Differences between the biomaterials were seen with respect to cell distribution, cell morphology, and the dynamics of GAG synthesis. The results show that ovine meniscal cells express their phenotype in both biomaterials. In terms of biology, collagen and hyaluronan are both suitable for tissue engineering in meniscal regeneration. It remains to be determined which scaffold possesses adequate biomechanical properties for successful in vivo application.