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Chang Y, Ping A, Chang C, Betz VM, Cai L, Ren B. Lactoferrin Mediates Enhanced Osteogenesis of Adipose-Derived Stem Cells: Innovative Molecular and Cellular Therapy for Bone Repair. Int J Mol Sci 2023; 24:ijms24021749. [PMID: 36675267 PMCID: PMC9864243 DOI: 10.3390/ijms24021749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/30/2022] [Accepted: 12/30/2022] [Indexed: 01/17/2023] Open
Abstract
A prospective source of stem cells for bone tissue engineering is adipose-derived stem cells (ADSCs), and BMP-2 has been proven to be highly effective in promoting the osteogenic differentiation of stem cells. Rarely has research been conducted on the impact of lactoferrin (LF) on ADSCs' osteogenic differentiation. As such, in this study, we examined the effects of LF and BMP-2 to assess the ability of LF to stimulate ADSCs' osteogenic differentiation. The osteogenic medium was supplemented with the LF at the following concentrations to culture ADSCs: 0, 10, 20, 50, 100, and 500 μg/mL. The Cell Counting Kit-8 (CCK-8) assay was used to measure the proliferation of ADSCs. Calcium deposition, alkaline phosphatase (ALP) staining, real-time polymerase chain reaction (RT-PCR), and an ALP activity assay were used to establish osteogenic differentiation. RNA sequencing analysis was carried out to investigate the mechanism of LF boosting the osteogenic development of ADSCs. In the concentration range of 0-100 μg/mL, LF concentration-dependently increased the proliferative vitality and osteogenic differentiation of ADSCs. At a dose of 500 μg/mL, LF sped up and enhanced differentiation, but inhibited ADSCs from proliferating. LF (100 and 500 μg/mL) produced more substantial osteoinductive effects than BMP-2. The PI3 kinase/AKT (PI3K/AKT) and IGF-R1 signaling pathways were significantly activated in LF-treated ADSCs. The in vitro study results showed that LF could effectively promote osteogenic differentiation of ADSCs by activating the PI3K/AKT and IGF-R1 pathways. In our in vitro investigation, an LF concentration of 100 μg/mL was optimal for osteoinduction and proliferation. Our study suggests that LF is an attractive alternative to BMP-2 in bone tissue engineering. As a bioactive molecule capable of inducing adipose stem cells to form osteoblasts, LF is expected to be clinically used in combination with biomaterials as an innovative molecular and cellular therapy to promote bone repair.
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Affiliation(s)
- Yiqiang Chang
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan 430070, China
| | - Ansong Ping
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan 430070, China
| | - Chunyu Chang
- College of Chemistry and Molecular Sciences, Engineering Research Center of Natural Polymer-based Medical Materials in Hubei Province and Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Volker M. Betz
- Department of Orthopedics and Trauma Surgery, Musculoskeletal University Center Munich (MUM), University Hospital LMU Munich, 81377 Munich, Germany
| | - Lin Cai
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan 430070, China
- Correspondence: (L.C.); (B.R.); Tel.: +86-138-8609-6467 (L.C.); +86-136-5175-6946 (B.R.)
| | - Bin Ren
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan 430070, China
- Correspondence: (L.C.); (B.R.); Tel.: +86-138-8609-6467 (L.C.); +86-136-5175-6946 (B.R.)
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Betz VM, Holzgruber M, Simon J, Uhlemann F, Niemeyer P, Müller PE, Niethammer TR. The Effect of Smoking on the Outcome of Matrix-Based Autologous Chondrocyte Implantation: Data from the German Cartilage Registry. J Knee Surg 2023; 36:181-187. [PMID: 34237778 DOI: 10.1055/s-0041-1731456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Smoking is known to have various deleterious effects on health. However, it is not clear whether smoking negatively affects the postoperative outcome following matrix-based autologous cartilage implantation (MACI) in the knee. The purpose of this study was to evaluate the effect of smoking on the outcome of MACI in the knee. A total of 281 patients receiving MACI in the knee between 2015 and 2018 were registered in the German Cartilage Database. The cohort was divided into ex-smokers, smokers, and nonsmokers. Data regarding the Knee Injury and Osteoarthritis Outcome Score (KOOS), the numeric rating scale (NRS) for pain, and satisfaction with the outcome were analyzed and compared. Follow-ups were performed at 6, 12, and 24 months after surgery. Of the 281 patients, 225 (80.1%) were nonsmokers, 43 (15.3%) were smokers, and 13 (4.6%) were ex-smokers. The three groups were comparable with respect to age, sex, body mass index (BMI), height, defect size, the need for additional reconstruction of the subchondral bone defect, number of previous knee surgeries, and defect location. However, nonsmokers had a significantly lower weight as compared with smokers. Besides a significantly lower preoperative NRS of nonsmokers as compared with smokers, there were no significant differences between the three groups with respect to KOOS, NRS, and satisfaction at 6, 12, and 24 months of follow-ups. The present study of data retrieved from the German Cartilage Registry suggests that the smoking status does not influence the outcome of MACI in the knee.
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Affiliation(s)
- Volker M Betz
- Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Martin Holzgruber
- Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Johanna Simon
- Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Felix Uhlemann
- Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Philipp Niemeyer
- Department of Orthopaedic Surgery and Traumatology, Freiburg University Hospital, Freiburg, Germany.,Department of Orthopaedic Surgery, Orthopädische Chirurgie München Clinic, Munich, Germany
| | - Peter E Müller
- Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Thomas R Niethammer
- Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
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Betz VM, Ren B, Betz OB, Jansson V, Müller PE. Osteoinduction within adipose tissue fragments by heterodimeric bone morphogenetic Proteins-2/6 and -2/7 versus homodimeric bone morphogenetic protein-2: Therapeutic implications for bone regeneration. J Gene Med 2021; 23:e3311. [PMID: 33527563 DOI: 10.1002/jgm.3311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/03/2021] [Accepted: 01/05/2021] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Fragments of subcutaneous adipose tissue that have been genetically modified to express bone morphogenetic protein-2 (BMP-2) regenerate large segmental osseous lesions in rodents. Gene-activated adipose tissue can be implanted into osseous defects without prior cell extraction and cell culture. The present study aimed to explore whether the heterodimers BMP-2/6 or BMP-2/7 exceed the osteoinductive effect of BMP-2 on adipose tissue. METHODS In an in vitro tissue culture system, freshly harvested rat subcutaneous adipose tissue was cultivated in the presence of either BMP-2 or BMP-2/6 or BMP-2/7 at a high (200 ng/ml) and low (50 ng/ml) concentration. Gene expression analysis as well as histological and immunohistochemical methods were applied to test for osteoinduction. RESULTS A concentration of 200 ng/ml of homodimeric BMP-2 induced osteogenic differentiation most potently, showing more calcification and a higher expression level of bone markers than both concentrations of BMP-2/6 or -2/7. A concentration of 50 ng/ml of BMP-2 was a significantly stronger osteogenic inducer than both concentrations of BMP-2/6 and the low concentration of BMP-2/7. The most potent heterodimeric driver of osteoinduction was BMP-2/7 at a high concentration, demonstrating effects similar to those of BMP-2 at a low concentration. CONCLUSIONS Homodimeric BMP-2 evoked osteoinduction within adipose tissue more potently and at a lower concentration than heterodimeric BMP-2/6 or BMP-2/7. This result agrees well with the fact that it might be easier to translate adipose grafts activated by homodimeric BMP-2 clinically. Preclinical in vivo gene transfer studies are necessary to confirm the results of the present study.
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Affiliation(s)
- Volker M Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Munich, Campus Grosshadern, LMU, Munich, Bavaria, Germany
| | - Bin Ren
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Munich, Campus Grosshadern, LMU, Munich, Bavaria, Germany
| | - Oliver B Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Munich, Campus Grosshadern, LMU, Munich, Bavaria, Germany.,Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Volkmar Jansson
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Munich, Campus Grosshadern, LMU, Munich, Bavaria, Germany
| | - Peter E Müller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Munich, Campus Grosshadern, LMU, Munich, Bavaria, Germany
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Ren B, Betz VM, Thirion C, Salomon M, Klar RM, Jansson V, Müller PE, Betz OB. Gene activated adipose tissue fragments as advanced autologous biomaterials for bone regeneration: osteogenic differentiation within the tissue and implications for clinical translation. Sci Rep 2019; 9:224. [PMID: 30659209 PMCID: PMC6338750 DOI: 10.1038/s41598-018-36283-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 10/26/2018] [Indexed: 02/06/2023] Open
Abstract
Cost-effective, expedited approaches for bone regeneration are urgently needed in an ageing population. Bone Morphogenetic Proteins (BMPs) stimulate osteogenesis but their efficacy is impeded by their short half-life. Delivery by genetically modified cells can overcome this problem. However, cell isolation and propagation represent significant obstacles for the translation into the clinic. Instead, complete gene activated fragments of adipose tissue hold great potential for bone repair. Here, using an in-vitro culture system, we investigated whether adenoviral transduction with human BMP-2 can promote osteogenic differentiation within adipose tissue fragments. Osteoinduction in adipose tissue fragments was evaluated by quantitative reverse transcriptase polymerase chain reaction, immunohistology and histomorphometry. BMP-2 transduced adipose tissue synthesized BMP-2 protein over 30 days peaking by day six, which significantly promoted osteogenic differentiation as indicated by increased calcium depositions, up-regulation of bone marker genes, and bone-related protein expression. Our results demonstrate that cells within adipose tissue fragments can differentiate osteogenically after BMP-2 transduction of cells on the surface of the adipose tissue. BMP-2 gene activated adipose tissue represents an advanced osteo-regenerative biomaterial that can actively contribute to osteogenesis and potentially enable the development of a novel, cost-effective, one-step surgical approach to bone repair without the need for cell isolation.
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Affiliation(s)
- Bin Ren
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr 15, 81377, Munich, Germany.
| | - Volker M Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr 15, 81377, Munich, Germany
| | - Christian Thirion
- Sirion Biotech GmbH, Am Klopferspitz 19, 82152, Martinsried, Germany
| | - Michael Salomon
- Sirion Biotech GmbH, Am Klopferspitz 19, 82152, Martinsried, Germany
| | - Roland M Klar
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr 15, 81377, Munich, Germany
| | - Volkmar Jansson
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr 15, 81377, Munich, Germany
| | - Peter E Müller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr 15, 81377, Munich, Germany
| | - Oliver B Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr 15, 81377, Munich, Germany
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Betz VM, Ren B, Messmer C, Jansson V, Betz OB, Müller PE. Bone morphogenetic protein-2 is a stronger inducer of osteogenesis within muscle tissue than heterodimeric bone morphogenetic protein-2/6 and -2/7: Implications for expedited gene-enhanced bone repair. J Gene Med 2018; 20:e3042. [DOI: 10.1002/jgm.3042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/18/2018] [Accepted: 06/19/2018] [Indexed: 11/09/2022] Open
Affiliation(s)
- Volker M. Betz
- Department of Gene Therapy; University of Ulm; Ulm Germany
- Center for Rehabilitation; RKU - University and Rehabilitation Hospitals Ulm; Ulm Germany
| | - Bin Ren
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
| | - Carolin Messmer
- Center for Rehabilitation; RKU - University and Rehabilitation Hospitals Ulm; Ulm Germany
| | - Volkmar Jansson
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
| | - Oliver B. Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
- Department of Chemical Engineering; Massachusetts Institute of Technology; Cambridge MA USA
| | - Peter E. Müller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
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Betz VM, Kochanek S, Rammelt S, Müller PE, Betz OB, Messmer C. Recent advances in gene-enhanced bone tissue engineering. J Gene Med 2018; 20:e3018. [PMID: 29601661 DOI: 10.1002/jgm.3018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/18/2018] [Accepted: 03/18/2018] [Indexed: 12/13/2022] Open
Abstract
The loss of bone tissue represents a critical clinical condition that is frequently faced by surgeons. Substantial progress has been made in the area of bone research, providing insight into the biology of bone under physiological and pathological conditions, as well as tools for the stimulation of bone regeneration. The present review discusses recent advances in the field of gene-enhanced bone tissue engineering. Gene transfer strategies have emerged as highly effective tissue engineering approaches for supporting the repair of the musculoskeletal system. By contrast to treatment with recombinant proteins, genetically engineered cells can release growth factors at the site of injury over extended periods of time. Of particular interest are the expedited technologies that can be applied during a single surgical procedure in a cost-effective manner, allowing translation from bench to bedside. Several promising methods based on the intra-operative genetic manipulation of autologous cells or tissue fragments have been developed in preclinical studies. Moreover, gene therapy for bone regeneration has entered the clinical stage with clinical trials for the repair of alveolar bone. Current trends in gene-enhanced bone engineering are also discussed with respect to the movement of the field towards expedited, translational approaches. It is possible that gene-enhanced bone tissue engineering will become a clinical reality within the next few years.
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Affiliation(s)
- Volker M Betz
- Department of Gene Therapy, University of Ulm, Ulm, Germany.,Center for Rehabilitation, RKU - University and Rehabilitation Hospitals Ulm, Ulm, Germany
| | | | - Stefan Rammelt
- University Center of Orthopedics and Traumatology and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, Dresden, Germany
| | - Peter E Müller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Oliver B Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany.,Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Carolin Messmer
- Center for Rehabilitation, RKU - University and Rehabilitation Hospitals Ulm, Ulm, Germany
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Ren B, Betz VM, Thirion C, Salomon M, Jansson V, Müller PE, Betz OB. Gene‐activated tissue grafts for sustained bone morphogenetic protein‐2 delivery and bone engineering: Is muscle with fascia superior to muscle and fat? J Tissue Eng Regen Med 2017; 12:1002-1011. [DOI: 10.1002/term.2575] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 08/06/2017] [Accepted: 09/12/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Bin Ren
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital GrosshadernLudwig‐Maximilians‐University Munich Munich Germany
| | - Volker M. Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital GrosshadernLudwig‐Maximilians‐University Munich Munich Germany
| | | | | | - Volkmar Jansson
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital GrosshadernLudwig‐Maximilians‐University Munich Munich Germany
| | - Peter E. Müller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital GrosshadernLudwig‐Maximilians‐University Munich Munich Germany
| | - Oliver B. Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital GrosshadernLudwig‐Maximilians‐University Munich Munich Germany
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Betz VM, Keller A, Foehr P, Thirion C, Salomon M, Rammelt S, Zwipp H, Burgkart R, Jansson V, Müller PE, Betz OB. BMP-2 gene activated muscle tissue fragments for osteochondral defect regeneration in the rabbit knee. J Gene Med 2017; 19. [PMID: 28744947 DOI: 10.1002/jgm.2972] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 07/19/2017] [Accepted: 07/19/2017] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Previously published data indicate that BMP-2 gene activated muscle tissue grafts can repair large bone defects in rats. This innovative abbreviated ex vivo gene therapy is appealing because it does not require elaborative and time-consuming extraction and expansion of cells. Hence, in the present study, we evaluated the potential of this expedited tissue engineering approach for regenerating osteochondral defects in rabbits. METHODS Autologous muscle tissue grafts from female White New Zealand rabbits were directly transduced with an adenoviral BMP-2 vector or remained unmodified. Osteochondral defects in the medial condyle of rabbit knees were treated with either BMP-2 activated muscle tissue implants or unmodified muscle tissue or remained empty. After 13 weeks, repair of osteochondral defects was examined by biomechanical indentation testing and by histology/imunohistochemistry applying an extended O'Driscoll scoring system and histomorphometry. RESULTS Biomechanical investigations revealed a trend towards slightly improved mechanical properties of the group receiving BMP-2 activated muscle tissue compared to unmodified muscle treatment and empty defect controls. However, a statistically significant difference was noted only between BMP-2 muscle and unmodified muscle treatment. Also, histological evaluation resulted in slightly higher histological scores and improved collagen I/II ratio without statistical significance in the BMP-2 treatment group. Histomorphometry indicated enhanced repair of subchondral bone after treatment with BMP-2 muscle, with a significantly larger bone area compared to untreated defects. CONCLUSIONS Gene activated muscle tissue grafts showed potential for osteochondral defect repair. There is room for improvement via the use of appropriate growth factor combinations.
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Affiliation(s)
- Volker M Betz
- University Center of Orthopaedics and Traumatology and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, Dresden, Germany
| | - Alexander Keller
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Peter Foehr
- Department of Orthopaedics and Sportsorthopaedics, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | | | | | - Stefan Rammelt
- University Center of Orthopaedics and Traumatology and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, Dresden, Germany.,DFG-Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Hans Zwipp
- University Center of Orthopaedics and Traumatology and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, Dresden, Germany.,DFG-Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Rainer Burgkart
- Department of Orthopaedics and Sportsorthopaedics, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Volkmar Jansson
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Peter E Müller
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Oliver B Betz
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
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Betz VM, Betz OB, Rosin T, Keller A, Thirion C, Salomon M, Manthey S, Augat P, Jansson V, Müller PE, Rammelt S, Zwipp H. An expedited approach for sustained delivery of bone morphogenetic protein-7 to bone defects using gene activated fragments of subcutaneous fat. J Gene Med 2016; 18:199-207. [DOI: 10.1002/jgm.2892] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 06/28/2016] [Accepted: 06/29/2016] [Indexed: 12/26/2022] Open
Affiliation(s)
- Volker M. Betz
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research; University Hospital Carl Gustav Carus Dresden, TU Dresden; Dresden Germany
| | - Oliver B. Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
| | - Tom Rosin
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research; University Hospital Carl Gustav Carus Dresden, TU Dresden; Dresden Germany
| | - Alexander Keller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
| | | | | | - Suzanne Manthey
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research; University Hospital Carl Gustav Carus Dresden, TU Dresden; Dresden Germany
| | - Peter Augat
- Institute of Biomechanics; Trauma Center Murnau; Murnau Germany
- Paracelsus Medical University; Salzburg Austria
| | - Volkmar Jansson
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
| | - Peter E. Müller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation; University Hospital Grosshadern, Ludwig-Maximilians-University Munich; Munich Germany
| | - Stefan Rammelt
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research; University Hospital Carl Gustav Carus Dresden, TU Dresden; Dresden Germany
| | - Hans Zwipp
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research; University Hospital Carl Gustav Carus Dresden, TU Dresden; Dresden Germany
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Betz VM, Sitoci-Ficici KH, Uckermann O, Leipnitz E, Iltzsche A, Thirion C, Salomon M, Zwipp H, Schackert G, Betz OB, Kirsch M. Gene-activated fat grafts for the repair of spinal cord injury: a pilot study. Acta Neurochir (Wien) 2016; 158:367-78. [PMID: 26592254 DOI: 10.1007/s00701-015-2626-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 10/28/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND Spinal cord injury (SCI) is a complex disease requiring a concerted multi-target approach. The most appropriate combination of therapeutic gene, cellular vehicle, and space filling scaffold still has to be determined. We present an approach that employs syngeneic adipose tissue serving as a three-dimensional biological implant, source of progenitor cells, and delivery system for therapeutic genes. In this pilot experiment, we evaluated the feasibility and short-term effects using gene-activated autologous fat grafts after SCI. METHODS An experimental SCI model was established in syngeneic Fischer 344 rats by a T9-T10 hemimyelonectomy. Fat tissue was harvested from two donor rats. Animals were divided into four groups and treated with either (i) fat grafts activated by an adenoviral vector carrying the human NT-3 cDNA, (ii) or BDNF, (iii) or with untreated fat grafts or (iv) remained untreated. Animals were euthanized either 7 or 21 days after surgery, and spinal cord tissue was investigated by histological and immunohistochemical methods. RESULTS NT-3 and BDNF were produced by gene-activated fat grafts for at least 21 days in vitro and in vivo. Fat tissue grafts remained stable at the site of implantation at 7 days and at 21 days. Neither BDNF-activated nor NT-3-activated fat graft had a detectable limiting effect on the neuronal degeneration. BDNF recruited microglia to perilesional site and attenuated their inflammatory response. CONCLUSIONS Gene-activated syngeneic fat tissue serves as a three-dimensional biological material delivering therapeutic molecules to the site of SCI over an extended period of time. The BDNF-fat graft attenuated the inflammatory response. Whether these findings translate into functional recovery will require extended observation times.
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Affiliation(s)
- Volker M Betz
- Department of Trauma and Reconstructive Surgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - K Hakan Sitoci-Ficici
- Department of Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Ortrud Uckermann
- Department of Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Elke Leipnitz
- Department of Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Anne Iltzsche
- Department of Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | | | | | - Hans Zwipp
- Department of Trauma and Reconstructive Surgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Gabriele Schackert
- Department of Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Oliver B Betz
- Department of Orthopedic Surgery, University Hospital Grosshadern, University of Munich, Munich, Germany.
| | - Matthias Kirsch
- Department of Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.
- DFG-Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany.
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Betz VM, Betz OB, Rosin T, Keller A, Thirion C, Salomon M, Manthey S, Augat P, Jansson V, Müller PE, Rammelt S, Zwipp H. The effect of BMP-7 gene activated muscle tissue implants on the repair of large segmental bone defects. Injury 2015; 46:2351-8. [PMID: 26454628 DOI: 10.1016/j.injury.2015.09.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 08/14/2015] [Accepted: 09/16/2015] [Indexed: 02/02/2023]
Abstract
BACKGROUND This study was conducted in order to investigate the effect of Bone Morphogenetic Protein-7 (BMP-7) transduced muscle cells on bone formation and to further develop an innovative abbreviated ex vivo gene therapy for bone repair. As conventional ex vivo gene therapy methods require an elaborative and time-consuming extraction and expansion of cells we evaluated an expedited approach. Fragments of muscle tissue were directly activated by BMP-7 cDNA and implanted into bone defects. METHODS 25 male, syngeneic Fischer 344 rats were used in the present study. Muscle tissue was harvested from two donor rats and either transduced with an adenovirus carrying the BMP-7 cDNA or remained unmodified. 5mm osseous defects in the right femora of 23 rats were treated with either unmodified muscle tissue (control group) or BMP-7 activated muscle tissue (treatment group). Six weeks after surgery, rat femora were evaluated by radiographs, micro-computed tomography (μCT) and histology. RESULTS Implantation of BMP-7 activated muscle grafts led to bony bridging in 5 out of 12 defects (41.7%) and to bone formation without bridging in 2 out of 12 defects. In 2 femoral defects of this group radiographs, μCT-imaging and histology did not reveal significant mineralization. Three animals of the BMP-7 treatment group had to be euthanized due to serious wound infection. The bone volume of the treatment group was significantly (p=0.007) higher compared to the control group. CONCLUSION This study shows that BMP-7 gene activated muscle fragments have the potential to regenerate critical-size segmental bone defects in rats. However, further development of this promising expedited treatment modality is required to improve the healing rate and to investigate if the high infection rate is related to treatment with BMP-7 activated muscle grafts.
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Affiliation(s)
- Volker M Betz
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, TU Dresden, Dresden, Germany.
| | - Oliver B Betz
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Tom Rosin
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, TU Dresden, Dresden, Germany
| | - Alexander Keller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | | | | | - Suzanne Manthey
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, TU Dresden, Dresden, Germany
| | - Peter Augat
- Institute of Biomechanics, Trauma Center Murnau, Murnau, Germany; Paracelsus Medical University, Salzburg, Austria
| | - Volkmar Jansson
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Peter E Müller
- Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Stefan Rammelt
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, TU Dresden, Dresden, Germany
| | - Hans Zwipp
- Department of Trauma and Reconstructive Surgery and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus Dresden, TU Dresden, Dresden, Germany
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Betz OB, Betz VM, Schröder C, Penzkofer R, Göttlinger M, Mayer-Wagner S, Augat P, Jansson V, Müller PE. Repair of large segmental bone defects: BMP-2 gene activated muscle grafts vs. autologous bone grafting. BMC Biotechnol 2013; 13:65. [PMID: 23927083 PMCID: PMC3750585 DOI: 10.1186/1472-6750-13-65] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 08/05/2013] [Indexed: 11/19/2022] Open
Abstract
Background Common cell based strategies for the treatment of osseous defects require the isolation and expansion of autologous cells. Since this makes such approaches time-consuming and expensive, we developed a novel expedited technology creating gene activated muscle grafts. We have previously shown that large segmental bone defects in rats can be regenerated by implantation of muscle tissue fragments activated by BMP-2 gene transfer. Results In the present study, we compared the bone healing capacities of such gene activated muscle grafts with bone isografts, mimicking autologous bone grafting, the clinical gold standard for treatment of bone defects in patients. Two of 14 male, syngeneic Fischer 344 rats used for this experiment served as donors for muscle and bone. Muscle tissue was harvested from both hind limbs and incubated with an adenoviral vector carrying the cDNA encoding BMP-2. Bone was harvested from the iliac crest and long bone epiphyses. Bone defects (5 mm) were created in the right femora of 12 rats and were filled with either BMP-2 activated muscle tissue or bone grafts. After eight weeks, femora were evaluated by radiographs, micro-computed tomography (μCT), and biomechanical testing. In the group receiving BMP-2 activated muscle grafts as well as in the bone-grafting group, 100% of the bone defects were healed, as documented by radiographs and μCT-imaging. Bone volume was similar in both groups and biomechanical stability of the two groups was statistically indistinguishable. Conclusions This study demonstrates that treatment of large bone defects by implantation of BMP-2 gene activated muscle tissue leads to similar bone volume and stability as bone isografts, mimicking autologous bone grafting.
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Majewski M, Porter RM, Betz OB, Betz VM, Clahsen H, Flückiger R, Evans CH. Improvement of tendon repair using muscle grafts transduced with TGF-β1 cDNA. Eur Cell Mater 2012; 23:94-101; discussion 101-2. [PMID: 22354460 PMCID: PMC4339190 DOI: 10.22203/ecm.v023a07] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Tendon rupture is a common injury. Inadequate endogenous repair often leaves patients symptomatic, with tendons susceptible to re-rupture. Administration of certain growth factors improves tendon healing in animal models, but their delivery remains a challenge. Here we evaluated the delivery of TGF-β1 to tendon defects by the implantation of genetically modified muscle grafts. Rat muscle biopsies were transduced with recombinant adenovirus encoding TGF-β1 and grafted onto surgically transected Achilles tendons in recipient animals. Tissue regenerates were compared to those of controls by biomechanical testing as well as histochemical and immunohistochemical analyses. Healing was greatly accelerated when genetically modified grafts were implanted into tendon defects, with the resulting repair tissue gaining nearly normal histological appearance as early as 2 weeks postoperatively. This was associated with decreased deposition of type III collagen in favour of large fibre bundles indicative of type I collagen. These differences in tendon composition coincided with accelerated restoration of mechanical strength. Tendon thickness increased in gene-treated animals at weeks 1 and 2, but by week 8 became significantly lower than that of controls suggesting accelerated remodelling. Thus localised TGF-β1 delivery via adenovirus-modified muscle grafts improved tendon healing in this rat model and holds promise for clinical application.
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Affiliation(s)
- Martin Majewski
- Orthopädische Klinik, Universität Basel, Basel, Switzerland,Address for Correspondence: Dr. med. Martin, Majewski, Orthopädische Universitätsklinik Basel, Spitalstrasse 21, CH-4031 Basel, Switzerland, Telephone number: 0041 61 328 78 13, Fax number: 0041 61 328 78 09,
| | - Ryan M. Porter
- Center for Molecular Orthopaedics, Brigham and Women’s Hospital, Harvard Medical School, Boston, USA,Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
| | - Oliver B. Betz
- Center for Molecular Orthopaedics, Brigham and Women’s Hospital, Harvard Medical School, Boston, USA
| | - Volker M. Betz
- Center for Molecular Orthopaedics, Brigham and Women’s Hospital, Harvard Medical School, Boston, USA
| | - Harald Clahsen
- Anatomisches Institut, Universität Düsseldorf, Düsseldorf, Germany
| | - Rudolf Flückiger
- Center for Molecular Orthopaedics, Brigham and Women’s Hospital, Harvard Medical School, Boston, USA
| | - Christopher H. Evans
- Center for Molecular Orthopaedics, Brigham and Women’s Hospital, Harvard Medical School, Boston, USA,Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
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Betz OB, Betz VM, Abdulazim A, Penzkofer R, Schmitt B, Schröder C, Mayer-Wagner S, Augat P, Jansson V, Müller PE. The Repair of Critical-Sized Bone Defects Using Expedited, AutologousBMP-2Gene-Activated Fat Implants. Tissue Eng Part A 2010; 16:1093-101. [DOI: 10.1089/ten.tea.2009.0656] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Oliver B. Betz
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Munich, Germany
| | - Volker M. Betz
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Munich, Germany
| | - Ahmed Abdulazim
- Trauma Center Murnau, Institute of Biomechanics, Murnau, Germany
| | - Rainer Penzkofer
- Trauma Center Murnau, Institute of Biomechanics, Murnau, Germany
| | - Bärbel Schmitt
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Munich, Germany
| | - Christian Schröder
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Munich, Germany
| | - Susanne Mayer-Wagner
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Munich, Germany
| | - Peter Augat
- Trauma Center Murnau, Institute of Biomechanics, Murnau, Germany
| | - Volkmar Jansson
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Munich, Germany
| | - Peter E. Müller
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Munich, Germany
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Betz OB, Betz VM, Abdulazim A, Penzkofer R, Schmitt B, Schröder C, Augat P, Jansson V, Müller PE. Healing of large segmental bone defects induced by expedited bone morphogenetic protein-2 gene-activated, syngeneic muscle grafts. Hum Gene Ther 2010; 20:1589-96. [PMID: 19572783 DOI: 10.1089/hum.2009.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Numerous preclinical studies have shown that osseous defects can be repaired by implanting bone morphogenetic protein (BMP)-2-transduced muscle cells. However, the drawback of this treatment modality is that it requires the isolation and long-term (approximately 3 weeks) culture of transduced autologous cells, which makes this approach cumbersome, time-consuming, and expensive. Therefore, we transferred BMP-2 cDNA directly to muscle tissue fragments that were held in culture for only 24 hr before implantation. We evaluated the ability of such gene-activated muscle grafts to induce bone repair. Two of 35 male, syngeneic Fischer 344 rats used in this study served as donors for muscle tissue. The muscle fragments remained unmodified or were incubated with an adenoviral vector carrying the cDNA encoding either green fluorescent protein (GFP) or BMP-2. Critical-size defects were created in the right femora of 33 rats and remained untreated or were filled (press fitted) with either unmodified muscle tissue or GFP-transduced muscle tissue or with BMP-2-activated muscle tissue. After 6 weeks, femora were evaluated by radiography, microcomputed tomography (muCT), histology, and biomechanical testing. Six weeks after implantation of BMP-2-activated muscle grafts, 100% of the bone defects were bridged, as documented by radiographs and muCT imaging, and showed formation of a neocortex, as evaluated by histology. Bone volumes of the femora repaired by BMP-2-transduced muscle were significantly (p = 0.006) higher compared with those of intact femora and the biomechanical stability was statistically indistinguishable. In contrast, control defects receiving no treatment, unmodified muscle, or GFP-transduced muscle did not heal. BMP-2 gene-activated muscle grafts are osteoregenerative composites that provide an expedited means of treating and subsequently healing large segmental bone defects.
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Affiliation(s)
- Oliver B Betz
- Laboratory for Biomechanics and Experimental Orthopedics, Department of Orthopedic Surgery, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, 81377 Munich, Germany.
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Betz OB, Betz VM, Abdulazim A, Penzkofer R, Schmitt B, Schröder C, Mayer-Wagner S, Augat P, Jansson V, Müller PE. The Repair of Critical Size Bone Defects using Expedited, Autologous BMP-2 Gene Activated Fat Implants. Tissue Eng Part A 2009. [DOI: 10.1089/ten.tea.2009.0204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstract
Many clinical conditions require the stimulation of bone growth. The use of recombinant bone morphogenetic proteins does not provide a satisfying solution to these conditions due to delivery problems and high cost. Gene therapy has emerged as a very promising approach for bone repair that overcomes limitations of protein-based therapy. Several preclinical studies have shown that gene transfer technology has the ability to deliver osteogenic molecules to precise anatomical locations at therapeutic levels for sustained periods of time. Both in-vivo and ex-vivo transduction of cells can induce bone formation at ectopic and orthotopic sites. Genetic engineering of adult stem cells from various sources with osteogenic genes has led to enhanced fracture repair, spinal fusion and rapid healing of bone defects in animal models. This review describes current viral and non-viral gene therapy strategies for bone tissue engineering and repair including recent work from the author's laboratory. In addition, the article discusses the potential of gene-enhanced tissue engineering to enter widespread clinical use.
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Affiliation(s)
- Volker M Betz
- Center for Molecular Orthopaedics, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA 02115, USA.
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Betz VM, Betz OB, Glatt V, Gerstenfeld LC, Einhorn TA, Bouxsein ML, Vrahas MS, Evans CH. Healing of segmental bone defects by direct percutaneous gene delivery: effect of vector dose. Hum Gene Ther 2007; 18:907-15. [PMID: 17910523 DOI: 10.1089/hum.2007.077] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Previous studies have demonstrated the ability of direct adenoviral BMP-2 (Ad.BMP-2) gene delivery to enhance bone repair. Nevertheless, in studies using a rat segmental defect model, it has not proved possible to achieve reliably full osseous union in all animals. To address this issue, we evaluated the effect of vector dose on healing. Critical-size defects were created in the right femora of 27 Sprague-Dawley rats. The defects received a single, intralesional, percutaneous injection of 2.7 x 10(7) (low dose), 2.7 x 10(8) (medium dose), or 2.7 x 10(9) (high dose) plaque-forming units of Ad.BMP-2. After 8 weeks, femora were evaluated by X-ray, dual-energy X-ray absorptiometry, microcomputed tomography (microCT), and histology. The high dose of vector bridged 100%, the medium dose 11%, and the low dose 25% of the defects, as evaluated by X-ray and microCT imaging. Bone mineral content and bone volume of the defects receiving the high dose of vector were significantly higher than those of both groups receiving lower doses. Histologically, defects treated with the high dose were filled by trabecular bone and small amounts of cartilage, whereas large areas of fibrous tissue and cartilage remained in the defects receiving lower doses. However, the newly formed bone lacked the structural organization of native bone, suggesting that further maturation is necessary.
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Affiliation(s)
- Volker M Betz
- Center for Molecular Orthopaedics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Betz OB, Betz VM, Nazarian A, Egermann M, Gerstenfeld LC, Einhorn TA, Vrahas MS, Bouxsein ML, Evans CH. Delayed administration of adenoviral BMP-2 vector improves the formation of bone in osseous defects. Gene Ther 2007; 14:1039-44. [PMID: 17460719 DOI: 10.1038/sj.gt.3302956] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The direct, local, administration of adenovirus carrying human BMP-2 cDNA (Ad.BMP-2) heals critical-sized femoral bone defects in rabbit and rat models. However, the outcome is suboptimal and the technology needs to provide a more reliable and uniform outcome. To this end, we investigated whether the timing of Ad.BMP-2 administration influenced the formation of mineralized tissue within the defect. Critical-sized defects were created in the femora of 28 Sprague-Dawley rats. Animals were injected intralesionally with a single, percutaneous injection of Ad.BMP-2 (4 x 10(8) plaque-forming units) either intraoperatively (day 0) or 24 h (day 1), 5 days or 10 days after surgery. The femora were evaluated 8 weeks after surgery by X-ray, microcomputed tomography, dual-energy X-ray absorptiometry and biomechanical testing. The incidence of radiological union was markedly increased when administration of Ad.BMP-2 was delayed until days 5 and 10, at which point 86% of the defects healed. These time points also provided greater bone mineral content within the defect site and improved the average mechanical strength of the healed bone. Thus, delaying the injection of Ad.BMP-2 until 5 or 10 days after surgery enables a greater percentage of critical-sized, segmental defects to achieve radiological union, producing a repair tissue with enhanced mineralization and greater mechanical strength.
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Affiliation(s)
- O B Betz
- Center for Molecular Orthopaedics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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Betz OB, Betz VM, Nazarian A, Pilapil CG, Vrahas MS, Bouxsein ML, Gerstenfeld LC, Einhorn TA, Evans CH. Direct percutaneous gene delivery to enhance healing of segmental bone defects. J Bone Joint Surg Am 2006; 88:355-65. [PMID: 16452748 DOI: 10.2106/jbjs.e.00464] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Healing of segmental bone defects can be induced experimentally with genetically modified osteoprogenitor cells, an ex vivo strategy that requires two operative interventions and substantial cost. Direct transfer of osteogenic genes offers an alternative, clinically expeditious, cost-effective approach. We evaluated its potential in a well-established, critical-size, rat femoral defect model. METHODS A critical-size defect was created in the right femur of forty-eight skeletally mature Sprague-Dawley rats. After twenty-four hours, each defect received a single, intralesional, percutaneous injection of adenovirus carrying bone morphogenetic protein-2 (Ad.BMP-2) or luciferase cDNA (Ad.luc) or it remained untreated. Healing was monitored with weekly radiographs. At eight weeks, the rats were killed and the femora were evaluated with dual-energy x-ray absorptiometry, micro-computed tomography, histological analysis, histomorphometry, and torsional mechanical testing. RESULTS Radiographically, 75% of the Ad.BMP-2-treated femora showed osseous union. Bone mineral content was similar between the Ad.BMP-2-treated femora (0.045 +/- 0.020 g) and the contralateral, intact femora (0.047 +/- 0.003 g). Histologically, 50% of the Ad.BMP-2-treated defects were bridged by lamellar, trabecular bone; the other 50% contained islands of cartilage. The control (Ad.luc-treated) defects were filled with fibrous tissue. Histomorphometry demonstrated a large difference in osteogenesis between the Ad.BMP-2 group (mean bone area, 3.25 +/- 0.67 mm(2)) and the controls (mean bone area, 0.65 +/- 0.67 mm(2)). By eight weeks, the Ad.BMP-2-treated femora had approximately one-fourth of the strength (mean, 0.07 +/- 0.04 Nm) and stiffness (mean, 0.5 +/- 0.4 Nm/rad) of the contralateral femora (0.3 +/- 0.08 Nm and 2.0 +/- 0.5 Nm/rad, respectively). CONCLUSIONS A single, percutaneous, intralesional injection of Ad.BMP-2 induces healing of critical-size femoral bone defects in rats within eight weeks. At this time, the repair tissue is predominantly trabecular bone, has normal bone mineral content, and has gained mechanical strength.
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Affiliation(s)
- Oliver B Betz
- Center for Molecular Orthopaedics, 221 Longwood Avenue, BLI-152, Boston, MA 02115, USA
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