Bioimaging of dexamethasone and TGF β-1 and its biological activities of chondrogenic differentiation in hydrogel constructs

• Published in: Journal of biomedical materials research. Part A 2008-11, Vol.87A (2), p.283-289
• Main Authors: Na, Kun, Kim, Sungwon, Sun, Bo Kyung, Woo, Dae Gyun, Yang, Han Na, Chung, Hyung-Min, Park, Keun-Hong
• Format: Article
• Language: English
• Subjects: Acrylic Resins - chemistry; Acrylic Resins - metabolism; Animals; Biocompatible Materials - chemistry; Biocompatible Materials - metabolism; Carbocyanines - chemistry; Carbocyanines - metabolism; cartilage; Cell Differentiation - drug effects; Cells, Cultured; chondrocytes; Chondrocytes - cytology; Chondrocytes - drug effects; Chondrocytes - physiology; Chondrogenesis - drug effects; Collagen Type II - genetics; Collagen Type II - metabolism; dexamethasone; Dexamethasone - chemistry; Dexamethasone - metabolism; Dexamethasone - pharmacology; Drug Carriers - chemistry; Drug Carriers - metabolism; Female; Fluorescein-5-isothiocyanate - chemistry; Fluorescein-5-isothiocyanate - metabolism; Fluorescent Dyes - chemistry; Fluorescent Dyes - metabolism; Glucocorticoids - chemistry; Glucocorticoids - metabolism; Glucocorticoids - pharmacology; Humans; Hydrogels - chemistry; Male; Materials Testing; Mice; Mice, Inbred BALB C; Mice, Nude; poly(NiPAAm-co-AAc); Rabbits; TGF β-1; Tissue Engineering - methods; Transforming Growth Factor beta1 - chemistry; Transforming Growth Factor beta1 - metabolism; Transforming Growth Factor beta1 - pharmacology
• ISSN: 1549-3296; 1552-4965
• DOI: 10.1002/jbm.a.31792

This study examined the efficacy of poly(NiPAAm‐co‐AAc) as an injectable drug delivery vehicle and a cell therapeutic agent in the form of a supporting matrix for the chondrogenic differentiation of rabbit chondrocytes. The hydrogel constructs, which consisted of embedded cells co‐encapsulating dexamethasone (Dex) and TGF β‐1 or unloaded Dex, were used as controls to determine the effects of Dex and TGF β‐1 on chondrogenic differentiation. The level of Dex and TGF β‐1 released was monitored using a bioimaging method. The amount of Dex released from hydrogel was faster than that of TGF β‐1. TGF β‐1 was present in hydrogel for more than 4 weeks after the injection. The level of the cartilage associated ECM proteins was examined by immunohistochemical staining for collagen type II as well as by Safranin‐O and Alcian blue (GAG) staining. These results highlight the potential of a thermo‐reversible hydrogel mixed with the chondrocytes and differentiation delivery material for applications in neocartilage formation. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008