The Journal of Bone and Joint Surgery (American) 85:866-871 (2003)
© 2003 The Journal of Bone and Joint Surgery, Inc.
Thoracoscopic Intradiscal Spine Fusion Using a Minimally Invasive Gene-Therapy Technique
K. Daniel Riew, MD,
Jueren Lou, MD,
Neill M. Wright, MD,
Su-Li Cheng, PhD,
Kyongtae T. Bae, MD, PhD and
Louis V. Avioli, MD
Investigation performed at the Department of Orthopaedic Surgery, Barnes-Jewish Hospitaland Washington University School of Medicine, St. Louis, Missouri
K. Daniel Riew, MD
Jueren Lou, MD
Neill M. Wright, MD
Su-Li Cheng, PhD
Kyongtae T. Bae, MD, PhD
Louis V. Avioli, MD
Department of Orthopaedic Surgery (K.D.R. and J.L.), Department of Neurological Surgery (N.M.W.), Division of Bone and Mineral Diseases, Department of Internal Medicine (S.-L.C. and L.V.A.), and Mallinckrodt Institute of Radiology (K.T.B.), Barnes-Jewish Hospital and Washington University School of Medicine, Suite 11300, One Barnes-Jewish Hospital Plaza Drive, St. Louis, MO 63110. E-mail address for K.D. Riew: riewd{at}msnotes.wustl.edu
The authors did not receive grants or outside funding in support of their research or preparation of this manuscript. They did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated.
Background: Gene therapy has been utilized to achieve posterior intertransverse process fusion in rodents. To our knowledge, however, no one has previously reported on the use of this technique to achieve anterior spinal fusion in mammals. The purpose of the present study was to determine if a gene-therapy technique can be utilized to achieve anterior intradiscal fusion in pigs with use of minimally invasive techniques.
Methods: Mesenchymal stem cells were isolated from each of three pigs, expanded in culture, and transduced with an adenovirus carrying either the gene for bone morphogenetic protein-2 (Adv-BMP2) or the control gene, ß-galactosidase (Adv-ßgal). In vitro, assays were performed to detect BMP-2 expression as well as protein markers of bone formation. In vivo, four thoracic disc spaces in each of three pigs were injected thoracoscopically with cells after 1 cm
3 of the disc had been removed. In each of the three pigs, two discs were injected with autologous mesenchymal stem cells transduced with Adv-BMP2, the third disc was injected with cells transduced with Adv-ßgal (control 1), and the fourth disc served as the sham-operated control (control 2). The three animals were killed six weeks after the implantation. Computerized tomographic scanning was performed on two of the specimens, and histological examination was performed on all specimens. The computerized tomographic scans and histological examinations were then interpreted in a blinded fashion.
Results: In the in vitro study, a human BMP-2 protein band was detected in the medium of Adv-BMP2-transduced stem cells but not in that of the control cells. The Adv-BMP2-transduced stem cells were associated with a fivefold increase in alkaline phosphatase activity compared with the controls as well as with matrix mineralization and increased protein expression of type-I collagen, osteopontin, and bone sialoprotein. In the in vivo study, radiographic examination demonstrated anterior spinal fusion in all six disc spaces that had been treated with implantation of Adv-BMP2-transduced stem cells. In contrast, the six control disc spaces had little or no intervening bone. Histological examination demonstrated bridging bone from end plate to end plate in all six disc spaces that had been treated with implantation of Adv-BMP2-transduced stem cells. The six control disc spaces had no bridging bone.
Conclusion: The Adv-BMP2-transduced mesenchymal stem cells produced BMP-2 protein. Further, the cells differentiated into osteoblasts and induced anterior spinal fusion in six of six disc spaces in this pig model. Although many technical and practical challenges remain, the results of the present study suggest that it may eventually be possible to use similar techniques to achieve anterior spinal fusion in humans.

CiteULike Connotea Del.icio.us Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
W. K. Hsu, J. C. Wang, N. Q. Liu, L. Krenek, P. A. Zuk, M. H. Hedrick, P. Benhaim, and J. R. Lieberman
Stem Cells from Human Fat as Cellular Delivery Vehicles in an Athymic Rat Posterolateral Spine Fusion Model
J. Bone Joint Surg. Am.,
May 1, 2008;
90(5):
1043 - 1052.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|