Biocompatibility of nano-hydroxyapatite/polyamide 66 composite with human bone mesenchymal stem cells

Abstract

Objective To explore the biocompatibility of nano-hydroxyapatite/polyamide 66 (nHA/PA66) with human bone mesenchymal stem cells (hBMSCs) after osteogenic induction. Methods After hBMSCs were isolated and cultured in vitro, the experiment was conducted in 3 groups. Group A were hBMSCs subjected to no osteogenic induction, group B hBMSCs subjected to osteogenic induction, and group C was the composite of nHA/PA66 with hBMSCs subjected to osteogenic induction. Adhesion of the cells onto the nHA/PA66 in group C was observed by electron microscope scanning. Growth and proliferation of the cells in groups B and C were detected by MTT test at 1, 2 and 3 weeks. The ability of osteogenic differentiation of hBMSCs in vitro was analyzed by alkaline phosphatase (ALP) activity and alizarin red staining. The ability of osteogenic differentiation of hBMSCs on nHA/PA66 was tested by ALP activity. Results Electron microscope scanning showed that the cells spread and attached well on the surface of the composite scaffold in group C; the proliferation of the cells in groups B and C showed no significant difference (P>0.05) . These suggested that the proliferation of hBMSCs was not affected by nHA/PA66. The number of mineralized nodules in group B was significantly larger than in group A (P 0.05) . These indicated that the hBMSCs were capable of osteogenic differentiation which was not affected by nHA/PA66. In groups B and C, the ALP activity of the cells at 12 days was significantly higher than at 6 days, indicating the ALP activity increased with increased induction time (P<0.05). Conclusion nHA/PA66 can be used as a carrier of hBMSCs in bone tissue engineering because hBMSCs can well adhere to, proliferate, and differentiate into bone on nHA/PA66 scaffolds. Key words: Bone marrow cells; Hydroxyapatite; Polyamides; Biocompatible materials