Effects of Insulin-Like Growth Factor I on Transforming Growth Factor β₁ Induced Chondrogenesis of Synovium-Derived Mesenchymal Stem Cells Cultured in a Polyglycolic Acid Scaffold

Abstract

The aim of this study was to demonstrate the induction of chondrogenesis by transforming growth factor (TGF)-β₁ from synovium-derived mesenchymal stem cells in a three-dimensional polyglycolic acid (PGA) scaffold, and to evaluate the effects of insulin-like growth factor (IGF)-I on TGF-β₁-induced chondrogenesis. Adult human synovial membranes were obtained from the knees of patients with osteoarthritis or rheumatoid arthritis. Cells were expanded in monolayers, seeded onto a PGA scaffold, and cultured for 4 or 8 weeks in chondrogenic medium containing TGF-β₁ with or without IGF-I. As a control, the cells were cultured in chondrogenic medium without TGF-β₁. The glycosaminoglycan content was quantified using dimethylmethylene blue dye-binding assay, and the DNA content was measured fluorometrically. Histological examination was also performed using safranin-O staining. The expression of mRNA for aggrecan and collagen type II was confirmed by RT-PCR. After 4 weeks of cultivation with TGF-β₁, the cells differentiated to a chondrocytic phenotype, and these chondrogeneses were more potent when cultured for 8 weeks. The combination of IGF-I and TGF-β₁ produced higher amounts of glycosaminoglycan than TGF-β₁ alone at 8 weeks. In conclusions, chondrogenesis from human synovium-derived mesenchymal cells was identified, and IGF-I plays a role in maintaining the extracellular matrix in combination with TGF-β₁.

Expansion in the presence of FGF-2 enhances the functional development of cartilaginous tissues engineered using infrapatellar fat pad derived MSCs

“…Therefore identifying expansion and differentiation conditions that promote a more chondrogenic phenotype is critical to enhancing their utility for cartilage tissue engineering applications. Differentiation conditions that have been shown to promote the chondrogenic potential of MSCs include a low oxygen (5%) microenvironment (Khan et al 2007;Buckley et al 2010a;Meyer et al 2010), various combinations of growth factors (Mastrogiacomo et al 2001;Sakimura et al 2006;Hennig et al 2007;Diekman et al 2010;Buxton et al 2011) and mechanical signals (Huang et al 2005;Mauck et al 2007;Huang et al 2010a;Huang et al 2010b;Kelly and Jacobs 2010;Li et al 2010; Thorpe et al 2010;Haugh et al 2011). …”

Cell-based Meniscal Tissue Engineering: A Case for Synoviocytes

“…Likewise, Bilgen and colleagues were not able to demonstrate either an increase in synoviocyte proliferation nor glycosaminoglycan production in response to the growth factor [12]. However, when used in concert with TGF-b, IGF-1 increases glycosaminoglycan production and signaling for Type II collagen and aggrecan when the treated synoviocytes were seeded either on PGA [34,74] or SIS scaffolds [84]. Interactions of TGF-b1 and IGF-1 on cultured chondrocytes have been well documented and despite TGF-b causing decreases in cellular IGF-1 production, increases in IGF-1 binding sites, and downregulation of IGF-1-induced receptor autophosphorylation, both insulin and IGF-1 are crucial in TGF-b-mediated re-expression of aggrecan and Type II collagen [68].…”

“…Scaffolds may further be defined as ''smart scaffolds'' if they carry with them some type of signal that can direct appropriate tissue formation either from the implanted cell type or from the surrounding resident cellular population. With respect to the delivery of synoviocytes for cartilage (hyaline or fibrocartilage) engineering, a number of different systems have been investigated including hydrogels (alginate [53,66] collagen [51,63,94], and gellan [28]), pellet cultures [63,80], micromasses [3,66], small intestinal submucosa (SIS) [84], hyaluronan-based scaffolds (Hyaff-111; FAB, Abano Terme, Padova, Italy) [56], polyglycolic acid (PGA) [67,74], PGA/poly (L) lactic acid (PLLA) combinations [34], and scaffold-free cell infusions [44,60]. With relatively few studies directly comparing delivery methods, elucidating an optimal carrier or scaffold from the literature alone is difficult.…”

“…Whereas PGA/PLLA combination scaffolds yielded poor results for meniscal application in one study [34], others have demonstrated excellent hyaline-like chondrogenesis using nonwoven PGA scaffolds [67,74]. The difference in study outcomes may be attributable to differing biochemical stimulation, however [34].…”

“…Insulin-like growth factor (IGF) has been assessed as a potential factor to further boost the performance of the TGF-b isoform with conflicting data. Where Sakimura et al [74] has found a combination of the two growth factors results in higher production of glycosaminoglycans from SMSCs cultured on PGA, Bilgen et al [12] found no such advantage. Also frequently investigated is the use of the isoform TGF-b3, which, in combination with other factors, is a powerful chondrogenic stimulus; a large body of work has now started to use a cocktail of TGF-b3 with bone morphogenic proteins (BMPs) and the synthetic glucocorticoid dexamethasone to consistently promote synovial-based chondroid matrix production [50,72,80,94].…”