Optimizing Chondrogenic Factors and Protein Delivery Methods for Cartilage Repair

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OCLC: 820554713

Abstract

Joint injuries are common and often result in damage to cartilage, which has a limited ability to repair itself. Tissue engineering is a promising approach for improving cartilage healing in which biomaterials and chemical factors are supplied to direct cells to create a new tissue. The objective of this thesis was to optimize cartilage-like extracellular matrix production by investigating the effects of Dexamethasone (Dex) and HB-IGF- I (heparin-binding insulinlike growth factor-1) on cells encapsulated in the self-assembling peptide RAD and agarose hydrogels.

Dex is a synthetic corticosteroid that has been shown to improve cartilage-like tissue production by bone marrow stromal cells (BMSCs), but the mechanisms underlying BMSC response to Dex are not understood. The hypothesis that the addition of Dex to chondrogenic medium would affect matrix production and aggrecanase activity of human and bovine BMSCs in RAD and agarose hydrogels was tested. The effects of Dex were dependent on the hydrogel material and the species/age of the BMSCs. Importantly, Dex reduced aggrecanase-mediated degradation of matrix in both agarose and RAD hydrogels and for both young bovine and adult human BMSCs.

HB-IGF-1, a fusion protein of the heparin binding domain of HB-EGF and IGF-1, can be retained in cartilage matrix and stimulate proteoglycan synthesis with a single dose, whereas unmodified IGF-1 easily diffuses out of cartilage tissue. The RAD peptide was used as a scaffold for retaining growth factor to stimulate encapsulated chondrocytes and adjacent cartilage tissue. RAD was modified by adsorption of HB-IGF-1 before and after RAD assembly, as well as adsorption of heparan sulfate (HS) and IGF-1. The RAD material retained HS adsorbed pre-assembly and HB-IGF-1 delivered in both adsorption methods. Adsorbed HB-IGF-1 and IGF-1 led to increased aggrecan content regardless of the method of adsorption. A trend was found for increased proteoglycan synthesis in adjacent explants as well.

RAD self-assembling hydrogels are a promising material for culturing BMSCs undergoing chondrogenesis, retaining, and delivering HB-IGF-1. Dex decreases aggrecanase activity of differentiating BMSCs and adsorbed HB-IGF-1 appears to enhance aggrecan production by encapsulating chondrocytes and adjacent tissue. These findings show potential for improving cartilage repair in vivo.

Cited Works (15)

Year	Entry
1998	Yoo JU, Barthel TS, Nishimura K, Solchaga L, Caplan AI, Goldberg VM, Johnstone B. The chondrogenic potential of human bone-marrow-derived mesenchymal progenitor cells. J Bone Joint Surg. December 1998;80A(12):1745-1757.
1967	Stegemann H, Stalder K. Determination of hydroxyproline. Clin Chim Acta. November 1, 1967;18(2):267.
2000	Ragan PM, Chin VI, Hung H-HK, Masuda K, Thonar EJ-MA, Arner EC, Grodzinsky AJ, Sandy JD. Chondrocyte extracellular matrix synthesis and turnover are influenced by static compression in a new alginate disk culture system. Arch Biochem Biophys. November 15, 2000;383(2):256-264.
2000	DeLise AM, Fischer L, Tuan RS. Cellular interactions and signaling in cartilage development. Osteoarthritis Cartilage. September 2000;8(5):309-334.
2001	Barry F, Boynton RE, Liu B, Murphy JM. Chondrogenic differentiation of mesenchymal stem cells from bone marrow: differentiation-dependent gene expression of matrix components. Exp Cell Res. August 15, 2001;268(2):189-200.
2006	Mauck RL, Yuan X, Tuan RS. Chondrogenic differentiation and functional maturation of bovine mesenchymal stem cells in long-term agarose culture. Osteoarthritis Cartilage. February 2006;14(2):179-189.
2005	Li W-J, Tuli R, Okafor C, Derfoul A, Danielson KG, Hall DJ, Tuan RS. A three-dimensional nanofibrous scaffold for cartilage tissue engineering using human mesenchymal stem cells. Biomaterials. February 2005;26(6):599-609.
1989	Sah RL-Y, Kim Y-J, Doong J-YH, Grodzinsky AJ, Plass AHK, Sandy JD. Biosynthetic response of cartilage explants to dynamic compression. J Orthop Res. 1989;7(5):619-636.
1996	Kim Y-J, Grodzinsky AJ, Plaas AHK. Compression of cartilage results in differential effects on biosynthetic pathways for aggrecan, link protein, and hyaluronan. Arch Biochem Biophys. April 15, 1996;328(2):331-340.
2008	Byers BA, Mauck RL, Chiang IE, Tuan RS. Transient exposure to transforming growth factor beta 3 under serum-free conditions enhances the biomechanical and biochemical maturation of tissue-engineered cartilage. Tissue Eng Part A. November 2008;14(11):1821-1834.
1999	Pittenger MF, Mackay AM, Beck SC, Jaiswal RK, Douglas R, Mosca JD, Moorman MA, Simonetti DW, Craig S, Marshak DR. Multilineage potential of adult human mesenchymal stem cells. Science. April 2, 1999;284(5411):143-147.
2000	Bonassar LJ, Grodzinsky AJ, Srinivasan A, Davila SG, Trippel SB. Mechanical and physicochemical regulation of the action of insulin-like growth factor-I on articular cartilage. Arch Biochem Biophys. July 1, 2000;379(1):57-63.
1988	Kim Y-J, Sah RLY, Doong J-YH, Grodzinsky AJ. Fluorometric assay of DNA in cartilage explants using Hoechst 33258. Anal Ciochem. October 1988;174(1):168-176.
1998	Johnstone B, Hering TM, Caplan AI, Goldberg VM, Yoo JU. In vitro chondrogenesis of bone marrow-derived mesenchymal progenitor cells. Exp Cell Res. January 10, 1998;238(1):265-272.
1982	Farndale RW, Sayers CA, Barrett AJ. A direct spectrophotometric microassay for sulfated glycosaminoglycans in cartilage cultures. Connect Tissue Res. 1982;9(4):247-248.