RESUMEN

In this study, human dental pulp stem cells (hDPSCs) are examined as a cellular source for bone tissue engineering using an in vivo-forming hydrogel. The hDPSCs are easily harvested in large quantities from extracted teeth. The stemness of harvested hDPSCs indicates their relative tolerance to ex vivo manipulation in culture. The in vitro osteogenic differentiation of hDPSCs is characterized using Alizarin Red S (ARS), von Kossa (VK), and alkaline phosphatase (ALP) staining. The solution of hDPSCs and a methoxy polyethylene glycol-polycaprolactone block copolymer (PC) is easily prepared by simple mixing at room temperature and in no more than 10 s it forms in vivo hydrogels after subcutaneous injection into rats. In vivo osteogenic differentiation of hDPSCs in the in vivo-forming hydrogel is confirmed by micro-computed tomography (CT), histological staining, and gene expression. Micro-CT analysis shows evidence of significant tissue-engineered bone formation in hDPSCs-loaded hydrogel in the presence of osteogenic factors. Differentiated osteoblasts in in vivo-forming hydrogel are identified by ARS and VK staining and are found to exhibit characteristic expression of genes like osteonectin, osteopontin, and osteocalcin. In conclusion, hDPSCs embedded in an in vivo-forming hydrogel may provide benefits as a noninvasive formulation for bone tissue engineering applications.

Asunto(s)

Diferenciación Celular/efectos de los fármacos , Pulpa Dental/citología , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Inyecciones , Osteogénesis/efectos de los fármacos , Células Madre/citología , Animales , Huesos/diagnóstico por imagen , Huesos/efectos de los fármacos , Huesos/patología , Diferenciación Celular/genética , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Implantes Experimentales , Inflamación/patología , Inyecciones Subcutáneas , Osteogénesis/genética , Poliésteres/farmacología , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Soluciones , Coloración y Etiquetado , Células Madre/efectos de los fármacos , Temperatura , Ingeniería de Tejidos , Viscosidad , Microtomografía por Rayos X

RESUMEN

BACKGROUND: Hydrolyzed polyacrylonitrile (HPAN) has attracted much attention as a hydrogel for a broad range of biomedical applications. Therefore, in this study, we prepared HPAN derivatives with controllable compositions by the radical polymerization of acrylonitrile (AN), methacrylic acid (MAA) and N-isopropylacrylamide (NIPAM) monomers. RESULTS: The prepared poly(AN-co-MAA-co-NIPAM) copolymers had different ratios of AN, MAA, and NIPAM and molecular weights ranging from 2000 to 50,000. The copolymers were prepared as films to examine their properties. The prepared copolymer films showed different solubilities, contact angles, and swelling ratios. The properties of the copolymer films were affected by the hydrophobic PAN segments and the hydrophilic PMAA or PNIPAM segments. CONCLUSION: Thus, we conclude that introducing PMAA and PNIPAM segments with different ratios and lengths into PAN segments could represent a method of controlling the hydrogel properties of copolymers.