Adenovirus-Mediated Therapeutic Gene Transfer: Matrix Synthesis of Human Intervertebral Disc Cells

Abstract

Study Design : In vitro experiment to determine the matrix synthesis of human intervertebral disc (IVD) cell to adenovirusmediated therapeutic gene transfer. Objectives : To elucidate proteoglycan and collagen synthesis of human IVD cells in vitro to adenovirus-mediated transfer of cDNA of transforming growth factor-beta 1(TGF-β1). Summary of Literature Review : Sophisticated method to delivery of growth factors, in continuous manner, is the genetic modification of disc cells through gene transfer. Confirming susceptibility of human IVD cell to adenovirus, anabolic response of human IVD cells to therapeutic gene transfer should be next step. Materials and Methods : IVD tissue was obtained from fourteen patients with grade III, IV degeneration. Isolation and culture of disc cells were performed. Disc cells were treated with either Ad/TGF-β1 exogenous TGF-β1. Control cultures were treated with either saline or Ad/luciferase. Newly synthesized proteoglycans were assessed by S-sulfate incorporation using chromatography on Sepadex G-25 in PD-10 columns. Uptake of H proline was used to measure synthesis of collagen and noncollagen protein. Results : Culture treated with Ad/TGF-β1 showed 3 fold increase in proteoglycan synthesis (p<0.05), culture with exogenous T G F -β1 failed to demonstrate increase in proteoglycan synthesis. In collagen and noncollagen synthesis, cultures with Ad/TGF-β1 and exogenous TGF-β1 showed similar 3.7 fold increase in collagen and 2.7 fold increase in noncollagen synthesis comparing control (p<0.05). Conclusion : Adenovirus-mediated gene transfer appears to be an efficient technique for modulating biologic activity of human intervertebral disc cells in terms of matrix synthesis.