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Harrer JA, Fulton TM, Sangadala S, Kaiser J, Devereaux EJ, Oliver C, Presciutti SM, Boden SD, Willett NJ. Local FK506 delivery induces osteogenesis in in vivo rat bone defect and rabbit spine fusion models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.08.584163. [PMID: 38559240 PMCID: PMC10979893 DOI: 10.1101/2024.03.08.584163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Bone grafting procedures are commonly used for the repair, regeneration, and fusion of bones in in a wide range of orthopaedic surgeries, including large bone defects and spine fusion procedures. Autografts are the clinical gold standard, though recombinant human bone morphogenetic proteins (rhBMPs) are often used, particularly in difficult clinical situations. However, treatment with rhBMPs can have off-target effects and significantly increase surgical costs, adding to patients' already high economic and mental burden. Recent studies have identified that FDA-approved immunosuppressant drug, FK506 (Tacrolimus), can also activate the BMP pathway by binding to its inhibitors. This study tested the hypothesis that FK506, as a standalone treatment, could induce osteogenic differentiation of human mesenchymal stromal cells (hMSCs), as well as functional bone formation in a rat segmental bone defect model and rabbit spinal fusion model. FK506 potentiated the effect of low dose BMP-2 to enhance osteogenic differentiation and mineralization of hMSCs in vitro. Standalone treatment with FK506 delivered on a collagen sponge, produced consistent bone bridging of a rat critically-sized femoral defect with functional mechanical properties comparable to naïve bone. In a rabbit single level posterolateral spine fusion model, treatment with FK506 delivered on a collagen sponge successfully fused the L5-L6 vertebrae at rates comparable to rhBMP-2 treatment. These data demonstrate the ability of FK506 to induce bone formation in human cells and two challenging in vivo models, and indicate FK506 can be utilized either as a standalone treatment or in conjunction with rhBMP to treat a variety of spine disorders.
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Affiliation(s)
- Julia Andraca Harrer
- Atlanta VA Medical Center, Decatur, GA 30033, USA
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA
- Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR 97403, USA
| | - Travis M. Fulton
- Atlanta VA Medical Center, Decatur, GA 30033, USA
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Sreedhara Sangadala
- Atlanta VA Medical Center, Decatur, GA 30033, USA
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jarred Kaiser
- Atlanta VA Medical Center, Decatur, GA 30033, USA
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Emily J. Devereaux
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | | | - Steven M. Presciutti
- Atlanta VA Medical Center, Decatur, GA 30033, USA
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Scott D. Boden
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Nick J. Willett
- Atlanta VA Medical Center, Decatur, GA 30033, USA
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA 30322, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA
- Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR 97403, USA
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2
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Rahmati M, Haffner M, Lee MA, Leach JK, Saiz AM. The critical impact of traumatic muscle loss on fracture healing: Basic science and clinical aspects. J Orthop Res 2024; 42:249-258. [PMID: 37990953 DOI: 10.1002/jor.25746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/05/2023] [Accepted: 11/20/2023] [Indexed: 11/23/2023]
Abstract
Musculoskeletal trauma, specifically fractures, is a leading cause of patient morbidity and disability worldwide. In approximately 20% of cases with fracture and related traumatic muscle loss, bone healing is impaired leading to fracture nonunion. Over the past few years, several studies have demonstrated that bone and the surrounding muscle tissue interact not only anatomically and mechanically but also through biochemical pathways and mediators. Severe damage to the surrounding musculature at the fracture site causes an insufficiency in muscle-derived osteoprogenitor cells that are crucial for fracture healing. As an endocrine tissue, skeletal muscle produces many myokines that act on different bone cells, such as osteoblasts, osteoclasts, osteocytes, and mesenchymal stem cells. Investigating how muscle influences fracture healing at cellular, molecular, and hormonal levels provides translational therapeutic solutions to this clinical challenge. This review provides an overview about the contributions of surrounding muscle tissue in directing fracture healing. The focus of the review is on describing the interactions between bone and muscle in both healthy and fractured environments. We discuss current progress in identifying the bone-muscle molecular pathways and strategies to harness these pathways as cues for accelerating fracture healing. In addition, we review the existing challenges and research opportunities in the field.
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Affiliation(s)
- Maryam Rahmati
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, California, USA
| | - Max Haffner
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, California, USA
| | - Mark A Lee
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, California, USA
| | - Jonathan Kent Leach
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, California, USA
- Department of Biomedical Engineering, University of California, Davis, Davis, California, USA
| | - Augustine M Saiz
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, California, USA
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3
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Schifino AG, Cooley MA, Zhong RX, Heo J, Hoffman DB, Warren GL, Greising SM, Call JA. Tibial bone strength is negatively affected by volumetric muscle loss injury to the adjacent muscle in male mice. J Orthop Res 2024; 42:123-133. [PMID: 37337074 PMCID: PMC10728344 DOI: 10.1002/jor.25643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 05/15/2023] [Accepted: 06/03/2023] [Indexed: 06/21/2023]
Abstract
This study's objective was to investigate how contractile strength loss associated with a volumetric muscle loss (VML) injury affects the adjacent tibial bone structural and functional properties in male C57BL/6J mice. Mice were randomized into one of two experimental groups: VML-injured mice that were injured at age 12 weeks and aged to 20 weeks (8 weeks postinjury, VML) and 20-week-old age-matched uninjured mice (Uninjured-20). Tibial bone strength, mid-diaphysis cortical geometry, intrinsic material properties, and metaphyseal trabecular bone structure were assessed by three-point bending and microcomputed tomography (µCT). The plantar flexor muscle group (gastrocnemius, soleus, plantaris) was analyzed for its functional capacities, that is, peak-isometric torque and peak-isokinetic power. VML-injured limbs had 25% less peak-isometric torque and 31% less peak-isokinetic power compared to those of Uninjured-20 mice (p < 0.001). Ultimate load, but not stiffness, was significantly less (10%) in tibias of VML-injured limbs compared to those from Uninjured-20 (p = 0.014). µCT analyses showed cortical bone thickness was 6% less in tibias of VML-injured limbs compared to Uninjured-20 (p = 0.001). Importantly, tibial bone cross-section moment of inertia, the primary determinant of bone ultimate load, was 16% smaller in bones of VML-injured limbs compared to bones from Uninjured-20 (p = 0.046). Metaphyseal trabecular bone structure was also altered up to 23% in tibias of VML-injured limbs (p < 0.010). These changes in tibial bone structure and function after a VML injury occur during a natural maturation phase between the age of 12 and 20 weeks, as evidenced by Uninjured-20 mice having greater tibial bone size and strength compared to uninjured-aged 12-week mice.
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Affiliation(s)
| | - Marion A. Cooley
- Department of Oral Biology and Diagnostic Sciences, Dental College of Georgia, August University, Augusta, GA USA
| | - Roger X. Zhong
- Department of Neuroscience and Regenerative Medicine, Augusta University, Augusta, GA USA
| | - Junwon Heo
- Department of Physiology & Pharmacology, University of Georgia, Athens, GA USA
| | | | - Gordon L. Warren
- Department of Physical Therapy, Georgia State University, Atlanta, GA USA
| | | | - Jarrod A. Call
- Department of Physiology & Pharmacology, University of Georgia, Athens, GA USA
- Regenerative Bioscience Center, University of Georgia, Athens, GA USA
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4
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Ziemkiewicz N, Au J, Chauvin HM, Garg K. Electrically stimulated eccentric contraction training enhances muscle mass, function, and size following volumetric muscle loss. J Orthop Res 2023; 41:2588-2598. [PMID: 37132367 DOI: 10.1002/jor.25591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 03/14/2023] [Accepted: 05/01/2023] [Indexed: 05/04/2023]
Abstract
Volumetric muscle loss (VML) overwhelms muscle's innate capacity for repair and can lead to permanent disability. The standard of care for VML injuries includes physical therapy, which can improve muscle function. The objective of this study was to develop and evaluate a rehabilitative therapy using electrically stimulated eccentric contraction training (EST) and determine the structural, biomolecular, and functional response of the VML-injured muscle. This study implemented EST using three different frequencies (50, 100, and 150 Hz) in VML-injured rats starting at 2 weeks postinjury. Four weeks of EST at 150 Hz showed a progressive increase in eccentric torque with an improvement in muscle mass (~39%), myofiber cross-sectional area, and peak isometric torque (~37.5%) relative to the untrained VML-injured sham group. EST at 150 Hz group also increased the number of large type 2B fibers (>5000 µm2 ). Elevated gene expression of markers associated with angiogenesis, myogenesis, neurogenesis, and an anti-inflammatory response was also observed. These results suggest that VML-injured muscles can respond and adapt to eccentric loading. The results of this study may aid in developing physical therapy regimens for traumatized muscles.
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Affiliation(s)
- Natalia Ziemkiewicz
- Department of Biomedical Engineering, Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, Missouri, USA
| | - Jeffrey Au
- Department of Biomedical Engineering, Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, Missouri, USA
| | - Hannah M Chauvin
- Department of Biomedical Engineering, Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, Missouri, USA
| | - Koyal Garg
- Department of Biomedical Engineering, Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, Missouri, USA
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Huang S, Wen J, Zhang Y, Bai X, Cui ZK. Choosing the right animal model for osteomyelitis research: Considerations and challenges. J Orthop Translat 2023; 43:47-65. [PMID: 38094261 PMCID: PMC10716383 DOI: 10.1016/j.jot.2023.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/27/2023] [Accepted: 10/09/2023] [Indexed: 03/22/2024] Open
Abstract
Osteomyelitis is a debilitating bone disorder characterized by an inflammatory process involving the bone marrow, bone cortex, periosteum, and surrounding soft tissue, which can ultimately result in bone destruction. The etiology of osteomyelitis can be infectious, caused by various microorganisms, or noninfectious, such as chronic nonbacterial osteomyelitis (CNO) and chronic recurrent multifocal osteomyelitis (CRMO). Researchers have turned to animal models to study the pathophysiology of osteomyelitis. However, selecting an appropriate animal model that accurately recapitulates the human pathology of osteomyelitis while controlling for multiple variables that influence different clinical presentations remains a significant challenge. In this review, we present an overview of various animal models used in osteomyelitis research, including rodent, rabbit, avian/chicken, porcine, minipig, canine, sheep, and goat models. We discuss the characteristics of each animal model and the corresponding clinical scenarios that can provide a basic rationale for experimental selection. This review highlights the importance of selecting an appropriate animal model for osteomyelitis research to improve the accuracy of the results and facilitate the development of novel treatment and management strategies.
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Affiliation(s)
| | | | - Yiqing Zhang
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Xiaochun Bai
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Zhong-Kai Cui
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
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Priddy LB, Krishnan L, Hettiaratchi MH, Karthikeyakannan S, Gupte N, Guldberg RE. Amniotic membrane attenuates heterotopic ossification following high-dose bone morphogenetic protein-2 treatment of segmental bone defects. J Orthop Res 2023; 41:130-140. [PMID: 35340049 PMCID: PMC9512937 DOI: 10.1002/jor.25324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 01/31/2022] [Accepted: 03/11/2022] [Indexed: 02/04/2023]
Abstract
Treatment of large bone defects with supraphysiological doses of bone morphogenetic protein-2 (BMP-2) has been associated with complications including heterotopic ossification (HO), inflammation, and pain, presumably due to poor spatiotemporal control of BMP-2. We have previously recapitulated extensive HO in our rat femoral segmental defect model by treatment with high-dose BMP-2 (30 μg). Using this model and BMP-2 dose, our objective was to evaluate the utility of a clinically available human amniotic membrane (AM) around the defect space for guided bone regeneration and reduction of HO. We hypothesized that AM surrounding collagen sponge would attenuate heterotopic ossification compared with collagen sponge alone. In vitro, AM retained more BMP-2 than a synthetic poly(ε-caprolactone) membrane through 21 days. In vivo, as hypothesized, the collagen + AM resulted in significantly less heterotopic ossification and correspondingly, lower total bone volume (BV), compared with collagen sponge alone. Although bone formation within the defect was delayed with AM around the defect, by 12 weeks, defect BVs were equivalent. Torsional stiffness was significantly reduced with AM but was equivalent to that of intact bone. Collagen + AM resulted in the formation of dense fibrous tissue and mineralized tissue, while the collagen group contained primarily mineralized tissue surrounded by marrow-like structures. Especially in conjunction with high doses of growth factor delivered via collagen sponge, these findings suggest AM may be effective as an overlay adjacent to bone healing sites to spatially direct bone regeneration and minimize heterotopic ossification.
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Affiliation(s)
- Lauren B. Priddy
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive NW, Atlanta, GA 30332, USA
- Current affiliation: Department of Agricultural and Biological Engineering, Mississippi State University, 130 Creelman Street, Mississippi State, MS 39762, USA
| | - Laxminarayanan Krishnan
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Marian H. Hettiaratchi
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive NW, Atlanta, GA 30332, USA
- Current affiliation: Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, 6231 University of Oregon, Eugene, OR 97403, USA
| | - Sukhita Karthikeyakannan
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Nikhil Gupte
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Robert E. Guldberg
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, Atlanta, GA 30332, USA
- Current affiliation: Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, 6231 University of Oregon, Eugene, OR 97403, USA
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Dunn A, Haas G, Madsen J, Ziemkiewicz N, Au J, Johnson D, West C, Chauvin H, Gagyi SM, Garg K. Biomimetic sponges improve functional muscle recovery following composite trauma. J Orthop Res 2022; 40:1039-1052. [PMID: 34289186 PMCID: PMC8776909 DOI: 10.1002/jor.25143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/02/2021] [Accepted: 06/24/2021] [Indexed: 02/04/2023]
Abstract
There is a dearth of therapies that are safe and effective for the treatment of volumetric muscle loss (VML), defined as the surgical or traumatic loss of muscle tissue, resulting in functional impairment. To address this gap in orthopedic care, we developed a porous sponge-like scaffold composed of extracellular matrix (ECM) proteins (e.g., gelatin, collagen, and laminin-111) and an immunosuppressant drug, FK-506. While the majority of VML injuries occur in orthopedic trauma cases, preclinical models typically study muscle injuries in isolation without a concomitant bone fracture. The goal of this study was to investigate the extent to which FK506 loaded biomimetic sponges support functional muscle regeneration and fracture healing in a composite trauma model involving VML injury to the tibialis anterior muscle and osteotomy (OST) to the tibia. In this model, implantation of the FK-506 loaded biomimetic sponges limited the extent of inflammation while increasing the total number of myofibers, mean myofiber cross-sectional area, myosin-to-collagen ratio, and peak isometric torque compared to untreated VML+OST muscles on Day 28. Although all tibia fractures were bridged by Day 28 post-injury, fracture healing was impaired in response to an adjacent VML injury. Sponge treatment increased bone callus volume, yet the bridged mineralized bone volume was not significantly different. Taken together, these results suggest that biomimetic sponges primarily benefitted muscle repair and may provide a promising therapy for traumatized muscle.
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Affiliation(s)
- Andrew Dunn
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | - Gabriel Haas
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | - Joshua Madsen
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | - Natalia Ziemkiewicz
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | - Jeffrey Au
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | - David Johnson
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | - Charles West
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | - Hannah Chauvin
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University
| | | | - Koyal Garg
- Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, Saint Louis University,Address correspondence to: Koyal Garg, PhD, Assistant Professor, Department of Biomedical Engineering, Parks College of Engineering, Aviation, and Technology, 3507 Lindell Blvd, St. Louis, MO 63103, Phone: 314.977.1434,
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8
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Subbiah R, Ruehle MA, Klosterhoff BS, Lin AS, Hettiaratchi MH, Willett NJ, Bertassoni LE, García AJ, Guldberg RE. Triple growth factor delivery promotes functional bone regeneration following composite musculoskeletal trauma. Acta Biomater 2021; 127:180-192. [PMID: 33823326 DOI: 10.1016/j.actbio.2021.03.066] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 03/28/2021] [Accepted: 03/31/2021] [Indexed: 12/20/2022]
Abstract
Successful bone healing in severe trauma depends on early revascularization to restore oxygen, nutrient, growth factor, and progenitor cell supply to the injury. Therapeutic angiogenesis strategies have therefore been investigated to promote revascularization following severe bone injuries; however, results have been inconsistent. This is the first study investigating the effects of dual angiogenic growth factors (VEGF and PDGF) with low-dose bone morphogenetic protein-2 (BMP-2; 2.5 µg) on bone healing in a clinically challenging composite bone-muscle injury model. Our hydrogel-based delivery systems demonstrated a more than 90% protein entrapment efficiency and a controlled simultaneous release of three growth factors over 28 days. Co-stimulation of microvascular fragment constructs with VEGF and PDGF promoted vascular network formation in vitro compared to VEGF or PDGF alone. In an in vivo model of segmental bone and volumetric muscle loss injury, combined VEGF (5 µg) and PDGF (7.5 µg or 15 µg) delivery with a low dose of BMP-2 significantly enhanced regeneration of vascularized bone compared to BMP-2 treatment alone. Notably, the regenerated bone mechanics reached ~60% of intact bone, a value that was previously only achieved by delivery of high-dose BMP-2 (10 µg) in this injury model. Overall, sustained delivery of VEGF, PDFG, and BMP-2 is a promising strategy to promote functional vascularized bone tissue regeneration following severe composite musculoskeletal injury. Although this study is conducted in a clinically relevant composite injury model in rats using a simultaneous release strategy, future studies are necessary to test the regenerative potential of spatiotemporally controlled delivery of triple growth factors on bone healing using large animal models. STATEMENT OF SIGNIFICANCE: Volumetric muscle loss combined with delayed union or non-union bone defect causes deleterious effects on bone regeneration even with the supplementation of bone morphogenetic protein-2 (BMP-2). In this study, the controlled delivery of dual angiogenic growth factors (vascular endothelial growth factor [VEGF] + Platelet-derived growth factor [PDGF]) increases vascular growth in vitro. Co-delivering VEGF+PDGF significantly increase the bone formation efficacy of low-dose BMP-2 and improves the mechanics of regenerated bone in a challenging composite bone-muscle injury model.
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Motherwell JM, Hendershot BD, Goldman SM, Dearth CL. Gait biomechanics: A clinically relevant outcome measure for preclinical research of musculoskeletal trauma. J Orthop Res 2021; 39:1139-1151. [PMID: 33458856 DOI: 10.1002/jor.24990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 12/01/2020] [Accepted: 01/11/2021] [Indexed: 02/04/2023]
Abstract
Traumatic injuries to the musculoskeletal system are the most prevalent of those suffered by United States Military Service members and accounts for two-thirds of initial hospital costs to the Department of Defense. These combat-related wounds often leave survivors with life-long disability and represent a significant impediment to the readiness of the fighting force. There are immense opportunities for the field of tissue engineering and regenerative medicine (TE/RM) to address these musculoskeletal injuries through regeneration of damaged tissues as a means to restore limb functionality and improve quality of life for affected individuals. Indeed, investigators have made promising advancements in the treatment for these injuries by utilizing small and large preclinical animal models to validate therapeutic efficacy of next-generation TE/RM-based technologies. Importantly, utilization of a comprehensive suite of functional outcome measures, particularly those designed to mimic data collected within the clinical setting, is critical for successful translation and implementation of these therapeutics. To that end, the objective of this review is to emphasize the clinical relevance and application of gait biomechanics as a functional outcome measure for preclinical research studies evaluating the efficacy of TE/RM therapies to treat traumatic musculoskeletal injuries. Specifically, common musculoskeletal injuries sustained by service members-including volumetric muscle loss, post-traumatic osteoarthritis, and composite tissue injuries-are examined as case examples to highlight the use of gait biomechanics as an outcome measure using small and large preclinical animal models.
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Affiliation(s)
- Jessica M Motherwell
- DoD-VA Extremity Trauma and Amputation Center of Excellence, Bethesda, Maryland, USA.,Department of Surgery, Uniformed Services University of the Health Sciences and Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Brad D Hendershot
- DoD-VA Extremity Trauma and Amputation Center of Excellence, Bethesda, Maryland, USA.,Department of Rehabilitation, Walter Reed National Military Medical Center, Bethesda, Maryland, USA.,Department of Rehabilitation Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Stephen M Goldman
- DoD-VA Extremity Trauma and Amputation Center of Excellence, Bethesda, Maryland, USA.,Department of Surgery, Uniformed Services University of the Health Sciences and Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Christopher L Dearth
- DoD-VA Extremity Trauma and Amputation Center of Excellence, Bethesda, Maryland, USA.,Department of Surgery, Uniformed Services University of the Health Sciences and Walter Reed National Military Medical Center, Bethesda, Maryland, USA
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10
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Mihaly E, Altamirano DE, Tuffaha S, Grayson W. Engineering skeletal muscle: Building complexity to achieve functionality. Semin Cell Dev Biol 2021; 119:61-69. [PMID: 33994095 DOI: 10.1016/j.semcdb.2021.04.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 04/19/2021] [Indexed: 12/12/2022]
Abstract
Volumetric muscle loss (VML) VML is defined as the loss of a critical mass of skeletal muscle that overwhelms the muscle's natural healing mechanisms, leaving patients with permanent functional deficits and deformity. The treatment of these defects is complex, as skeletal muscle is a composite structure that relies closely on the action of supporting tissues such as tendons, vasculature, nerves, and bone. The gold standard of treatment for VML injuries, an autologous muscle flap transfer, suffers from many shortcomings but nevertheless remains the best clinically available avenue to restore function. This review will consider the use of composite tissue engineered constructs, with multiple components that act together to replicate the function of an intact muscle, as an alternative to autologous muscle flaps. We will discuss recent advances in the field of tissue engineering that enable skeletal muscle constructs to more closely reproduce the functionality of an autologous muscle flap by incorporating vasculature, promoting innervation, and reconstructing the muscle-tendon boundary. Additionally, our understanding of the cellular composition of skeletal muscle has evolved to recognize the importance of a diverse variety of cell types in muscle regeneration, including fibro/adipogenic progenitors and immune cells like macrophages and regulatory T cells. We will address recent advances in our understanding of how these cell types interact with, and can be incorporated into, implanted tissue engineered constructs.
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Affiliation(s)
- Eszter Mihaly
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Dallas E Altamirano
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Sami Tuffaha
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Curtis National Hand Center, MedStar Union Memorial Hospital, Baltimore, MD 21218, USA
| | - Warren Grayson
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Materials Science & Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Department of Chemical & Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Institute for NanoBioTechnology (INBT), Johns Hopkins University School of Engineering, Baltimore, MD 21218, USA.
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11
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Vantucci CE, Krishan L, Cheng A, Prather A, Roy K, Guldberg RE. BMP-2 delivery strategy modulates local bone regeneration and systemic immune responses to complex extremity trauma. Biomater Sci 2021; 9:1668-1682. [PMID: 33409509 PMCID: PMC8256799 DOI: 10.1039/d0bm01728k] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Bone nonunions arising from large bone defects and composite injuries remain compelling challenges for orthopedic surgeons. Biological changes associated with nonunions, such as systemic immune dysregulation, can contribute to an adverse healing environment. Bone morphogenetic protein 2 (BMP-2), an osteoinductive and potentially immunomodulatory growth factor, is a promising strategy; however, burst release from the clinical standard collagen sponge delivery vehicle can result in adverse side effects such as heterotopic ossification (HO) and irregular bone structure, especially when using supraphysiological BMP-2 doses for complex injuries at high risk for nonunion. To address this challenge, biomaterials that strongly bind BMP-2, such as heparin methacrylamide microparticles (HMPs), may be used to limit exposure and spatially constrain proteins within the injury site. Here, we investigate moderately high dose BMP-2 delivered in HMPs within an injectable hydrogel system in two challenging nonunion models exhibiting characteristics of systemic immune dysregulation. The HMP delivery system increased total bone volume and decreased peak HO compared to collagen sponge delivery of the same BMP-2 dose. Multivariate analyses of systemic immune markers showed the collagen sponge group correlated with markers that are hallmarks of systemic immune dysregulation, including immunosuppressive myeloid-derived suppressor cells, whereas the HMP groups were associated with immune effector cells, including T cells, and cytokines linked to robust bone regeneration. Overall, our results demonstrate that HMP delivery of moderately high doses of BMP-2 promotes repair of complex bone nonunion injuries and that local delivery strategies for potent growth factors like BMP-2 may positively affect the systemic immune response to traumatic injury.
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Affiliation(s)
- Casey E Vantucci
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA and Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Laxminarayanan Krishan
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Albert Cheng
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA and George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Ayanna Prather
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Krishnendu Roy
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA and Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Robert E Guldberg
- Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR, USA.
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12
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Vantucci CE, Ahn H, Fulton T, Schenker ML, Pradhan P, Wood LB, Guldberg RE, Roy K, Willett NJ. Development of systemic immune dysregulation in a rat trauma model of biomaterial-associated infection. Biomaterials 2021; 264:120405. [PMID: 33069135 PMCID: PMC8117743 DOI: 10.1016/j.biomaterials.2020.120405] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 09/09/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022]
Abstract
Orthopedic biomaterial-associated infections remain a major clinical challenge, with Staphylococcus aureus being the most common pathogen. S. aureus biofilm formation enhances immune evasion and antibiotic resistance, resulting in a local, indolent infection that can persist long-term without symptoms before eventual hardware failure, bone non-union, or sepsis. Immune modulation is an emerging strategy to combat host immune evasion by S. aureus. However, most immune modulation strategies are focused on local immune responses at the site of infection, with little emphasis on understanding the infection-induced and orthopedic-related systemic immune responses of the host, and their role in local infection clearance and tissue regeneration. This study utilized a rat bone defect model to investigate how implant-associated infection affects the systemic immune response. Long-term systemic immune dysregulation was observed with a significant systemic decrease in T cells and a concomitant increase in immunosuppressive myeloid-derived suppressor cells (MDSCs) compared to non-infected controls. Further, the control group exhibited a regulated and coordinated systemic cytokine response, which was absent in the infection group. Multivariate analysis revealed high levels of MDSCs to be most correlated with the infection group, while high levels of T cells were most correlated with the control group. Locally, the infection group had attenuated macrophage infiltration and increased levels of MDSCs in the local soft tissue compared to non-infected controls. These data reveal the widespread impacts of an orthopedic infection on both the local and the systemic immune responses, uncovering promising targets for diagnostics and immunotherapies that could optimize treatment strategies and ultimately improve patient outcomes.
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Affiliation(s)
- Casey E Vantucci
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Hyunhee Ahn
- The Atlanta Veterans Affairs Medical Center Atlanta, Decatur, GA, USA; Department of Orthopaedics, Emory University, Atlanta, GA, USA
| | - Travis Fulton
- The Atlanta Veterans Affairs Medical Center Atlanta, Decatur, GA, USA; Department of Orthopaedics, Emory University, Atlanta, GA, USA
| | - Mara L Schenker
- Department of Orthopaedics, Emory University, Atlanta, GA, USA; Grady Memorial Hospital, Atlanta, GA, USA
| | - Pallab Pradhan
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Levi B Wood
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Robert E Guldberg
- Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR, USA
| | - Krishnendu Roy
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA.
| | - Nick J Willett
- The Atlanta Veterans Affairs Medical Center Atlanta, Decatur, GA, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Department of Orthopaedics, Emory University, Atlanta, GA, USA.
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13
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Goldman SM, Feng JP, Corona BT. Volumetric muscle loss disrupts length-dependent architectural and functional characteristics of skeletal muscle. Connect Tissue Res 2021; 62:72-82. [PMID: 32660287 DOI: 10.1080/03008207.2020.1789608] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Purpose/Aim: Skeletal muscle architecture is a primary determinant of function. Volumetric muscle loss (VML) injury is destructive; however, the impact on muscle architecture is uncharacterized. Methods: Architectural and functional effects of VML were assessed in rat tibialis anterior (TA) muscle model 4 weeks post-injury. Results: VML caused a 31% and 33% reduction in muscle weight (p < 0.001) and fiber length (p = 0.002), respectively, culminating a 34% reduction of fiber to muscle length ratio (FL:ML; p < 0.001). Fiber pennation angle (+14%; p = 0.150) and physiological cross-sectional area (PCSA; -12%; p = 0.220) were unchanged. VML injury reduced peak isometric force (Po) by 36% (p < 0.001), specific force (sPo = Po/PCSA) by 41% (vs. Po, p > 0.999), and force per gram muscle weight (Po/mw) by 18% (vs. Po, p < 0.001). VML injury increased the length at which Po was produced (Lo) by 8% (p = 0.009), and reduced functional excursion by 35% (p = 0.035). Conclusion: The architectural changes after VML injury preserved PCSA, and therefore preserved "potential" maximal force-producing capacity. At most, only half the Po deficit was due directly to the cumulative effect of horizontal and longitudinal tissue loss. Highlighting the impact of longitudinal muscle loss, VML injury reduced fiber length, and FL:ML and grossly disrupted length-dependent functional properties. These findings raise the importance of augmenting length-dependent muscle properties to optimize functional recovery after VML injury.
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Affiliation(s)
- Stephen M Goldman
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research , Fort Sam Houston, TX, USA.,DoD-VA Extremity Trauma and Amputation Center of Excellence , Fort Sam Houston, TX, USA.,Department of Surgery, Uniformed Services University of the Health Sciences , Bethesda, MD, USA.,Department of Surgery, Walter Reed National Military Medical Center , Bethesda, MD, USA
| | - Jonathan P Feng
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research , Fort Sam Houston, TX, USA
| | - Benjamin T Corona
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research , Fort Sam Houston, TX, USA
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14
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Subbiah R, Cheng A, Ruehle MA, Hettiaratchi MH, Bertassoni LE, Guldberg RE. Effects of controlled dual growth factor delivery on bone regeneration following composite bone-muscle injury. Acta Biomater 2020; 114:63-75. [PMID: 32688092 DOI: 10.1016/j.actbio.2020.07.026] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 07/14/2020] [Accepted: 07/14/2020] [Indexed: 10/23/2022]
Abstract
The objective of this study was to investigate the controlled release of two growth factors (BMP-2 and VEGF) as a treatment strategy for bone healing in clinically challenging composite injuries, consisting of a femoral segmental bone defect and volumetric muscle loss. This is the first investigation of dual growth factor delivery in a composite injury model using an injectable delivery system consisting of heparin microparticles and alginate gel. The loading efficiency of growth factors into these biomaterials was found to be >90%, revealing a strong affinity of VEGF and BMP-2 to heparin and alginate. The system could achieve simultaneous or tunable release of VEGF and BMP-2 by varying the loading strategy. Single growth factor delivery (VEGF or BMP-2 alone) significantly enhanced vascular growth in vitro. However, no synergistic effect was observed for dual growth factor (BMP-2 + VEGF) delivery in vitro. Effective bone healing was achieved in all treatment groups (BMP-2, simultaneous or tunable delivery of BMP-2 and VEGF) in the composite injury model. The mechanics of the regenerated bone reached a maximum strength of ~52% of intact bone with tunable delivery of VEGF and BMP-2. Overall, simultaneous or tunable co-delivery of low-dose BMP-2 and VEGF failed to fully restore the mechanics of bone in this injury model. Given the severity of the composite injury, VEGF alone may not be sufficient to establish mature and stable blood vessels when compared with previous studies co-delivering BMP-2+VEGF enhanced bone tissue regeneration. Hence, future studies are warranted to develop an alternative treatment strategy focusing on better control over growth factor dose, spatiotemporal delivery, and additional growth factors to regenerate fully functional bone tissue. STATEMENT OF SIGNIFICANCE: We have developed an injectable delivery system consisting of heparin microparticles and an alginate hydrogel that is capable of delivering multiple growth factors in a tunable manner. We used this delivery system to deliver BMP-2 and VEGF in a rodent model of composite bone-muscle injury that mimics clinical type III open fractures. An advanced treatment strategy is necessary for these injuries in order to avoid the negative side effects of high doses of growth factors and because it has been shown that the addition of a muscle injury in this model attenuates the bone regenerative effect of BMP-2. This is the first study to test the effects of dual growth factor delivery (BMP-2/VEGF) on bone healing in a composite bone-muscle injury model and is expected to open up new directions in protein delivery for regenerative medicine.
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15
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Biguetti CC, Couto MCR, Silva ACR, Shindo JVTC, Rosa VM, Shinohara AL, Andreo JC, Duarte MAH, Wang Z, Brotto M, Matsumoto MA. New Surgical Model for Bone-Muscle Injury Reveals Age and Gender-Related Healing Patterns in the 5 Lipoxygenase (5LO) Knockout Mouse. Front Endocrinol (Lausanne) 2020; 11:484. [PMID: 32849277 PMCID: PMC7431610 DOI: 10.3389/fendo.2020.00484] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/22/2020] [Indexed: 12/31/2022] Open
Abstract
Signaling lipid mediators released from 5 lipoxygenase (5LO) pathways influence both bone and muscle cells, interfering in their proliferation and differentiation capacities. A major limitation to studying inflammatory signaling pathways in bone and muscle healing is the inadequacy of available animal models. We developed a surgical injury model in the vastus lateralis (VL) muscle and femur in 129/SvEv littermates mice to study simultaneous musculoskeletal (MSK) healing in male and female, young (3 months) and aged (18 months) WT mice compared to mice lacking 5LO (5LOKO). MSK defects were surgically created using a 1-mm punch device in the VA muscle followed by a 0.5-mm round defect in the femur. After days 7 and 14 post-surgery, the specimens were removed for microtomography (microCT), histopathology, and immunohistochemistry analyses. In addition, non-injured control skeletal muscles along with femur and L5 vertebrae were analyzed. Bones were microCT phenotyped, revealing that aged female WT mice presented reduced BV/TV and trabecular parameters compared to aged males and aged female 5LOKO mice. Skeletal muscles underwent a customized targeted lipidomics investigation for profiling and quantification of lipid signaling mediators (LMs), evidencing age, and gender related-differences in aged female 5LOKO mice compared to matched WT. Histological analysis revealed a suitable bone-healing process with osteoid deposition at day 7 post-surgery, followed by woven bone at day 14 post-surgery, observed in all young mice. Aged WT females displayed increased inflammatory response at day 7 post-surgery, delayed bone matrix maturation, and increased TRAP immunolabeling at day 14 post-surgery compared to 5LOKO females. Skeletal muscles of aged animals showed higher levels of inflammation in comparison to young controls at day 14 post-surgery; however, inflammatory process was attenuated in aged 5LOKO mice compared to aged WT. In conclusion, this new model shows that MSK healing is influenced by age, gender, and the 5LO pathway, which might serve as a potential target to investigate therapeutic interventions and age-related MSK diseases. Our new model is suitable for bone-muscle crosstalk studies.
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Affiliation(s)
- Claudia Cristina Biguetti
- Department of Basic Sciences, School of Dentistry, São Paulo State University (UNESP), Araçatuba, Brazil
- Bone-Muscle Research Center, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington, TX, United States
| | - Maira Cristina Rondina Couto
- Department of Health Sciences, Universidade Do Sagrado Coração, Bauru, Brazil
- Bauru School of Dentistry, University of São Paulo, FOB-USP, São Paulo, Brazil
| | | | | | - Vinicius Mateus Rosa
- Department of Basic Sciences, School of Dentistry, São Paulo State University (UNESP), Araçatuba, Brazil
| | | | - Jesus Carlos Andreo
- Bauru School of Dentistry, University of São Paulo, FOB-USP, São Paulo, Brazil
| | | | - Zhiying Wang
- Bone-Muscle Research Center, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington, TX, United States
| | - Marco Brotto
- Bone-Muscle Research Center, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington, TX, United States
| | - Mariza Akemi Matsumoto
- Department of Basic Sciences, School of Dentistry, São Paulo State University (UNESP), Araçatuba, Brazil
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16
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Dewey MJ, Johnson EM, Slater ST, Milner DJ, Wheeler MB, Harley BAC. Mineralized collagen scaffolds fabricated with amniotic membrane matrix increase osteogenesis under inflammatory conditions. Regen Biomater 2020; 7:247-258. [PMID: 32523727 PMCID: PMC7266662 DOI: 10.1093/rb/rbaa005] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/17/2020] [Accepted: 02/17/2020] [Indexed: 12/12/2022] Open
Abstract
Defects in craniofacial bones occur congenitally, after high-energy impacts, and during the course of treatment for stroke and cancer. These injuries are difficult to heal due to the overwhelming size of the injury area and the inflammatory environment surrounding the injury. Significant inflammatory response after injury may greatly inhibit regenerative healing. We have developed mineralized collagen scaffolds that can induce osteogenic differentiation and matrix biosynthesis in the absence of osteogenic media or supplemental proteins. The amniotic membrane is derived from placentas and has been recently investigated as an extracellular matrix to prevent chronic inflammation. Herein, we hypothesized that a mineralized collagen–amnion composite scaffold could increase osteogenic activity in the presence of inflammatory cytokines. We report mechanical properties of a mineralized collagen–amnion scaffold and investigated osteogenic differentiation and mineral deposition of porcine adipose-derived stem cells within these scaffolds as a function of inflammatory challenge. Incorporation of amniotic membrane matrix promotes osteogenesis similarly to un-modified mineralized collagen scaffolds, and increases in mineralized collagen–amnion scaffolds under inflammatory challenge. Together, these findings suggest that a mineralized collagen–amnion scaffold may provide a beneficial environment to aid craniomaxillofacial bone repair, especially in the course of defects presenting significant inflammatory complications.
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Affiliation(s)
- Marley J Dewey
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA
| | - Eileen M Johnson
- Department of Bioengineering, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA
| | - Simona T Slater
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA
| | - Derek J Milner
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA
| | - Matthew B Wheeler
- Department of Bioengineering, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA.,Department of Animal Sciences, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA
| | - Brendan A C Harley
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave., Urbana, IL 61801, USA
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17
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Collier CD, Hausman BS, Zulqadar SH, Din ES, Anderson JM, Akkus O, Greenfield EM. Characterization of a reproducible model of fracture healing in mice using an open femoral osteotomy. Bone Rep 2020; 12:100250. [PMID: 32090156 PMCID: PMC7025178 DOI: 10.1016/j.bonr.2020.100250] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/26/2020] [Accepted: 02/03/2020] [Indexed: 01/03/2023] Open
Abstract
Purpose The classic fracture model, described by Bonnarens and Einhorn in 1984, enlists a blunt guillotine to generate a closed fracture in a pre-stabilized rodent femur. However, in less experienced hands, this technique yields considerable variability in fracture pattern and requires highly-specialized equipment. This study describes a reproducible and low-cost model of mouse fracture healing using an open femoral osteotomy. Methods Femur fractures were produced in skeletally mature male and female mice using an open femoral osteotomy after intramedullary stabilization. Mice were recovered for up to 28 days prior to analysis with microradiographs, histomorphometry, a novel μCT methodology, and biomechanical torsion testing at weekly intervals. Results Eight mice were excluded due to complications (8/193, 4.1%), including unacceptable fracture pattern (2/193, 1.0%). Microradiographs showed progression of the fracture site to mineralized callus by 14 days and remodelling 28 days after surgery. Histomorphometry from 14 to 28 days revealed decreased cartilage area and maintained bone area. μCT analysis demonstrated a reduction in mineral surface from 14 to 28 days, stable mineral volume, decreased strut number, and increased strut thickness. Torsion testing at 21 days showed that fractured femurs had 61% of the ultimate torque, 63% of the stiffness, and similar twist to failure when compared to unfractured contralateral femurs. Conclusions The fracture model described herein, an open femoral osteotomy, demonstrated healing comparable to that reported using closed techniques. This simple model could be used in future research with improved reliability and reduced costs compared to the current options. This study characterized a simple and reproducible model of fracture healing in mice using an open femoral osteotomy. Analysis by x-ray, histomorphometry, µCT, and biomechanical testing demonstrated healing comparable to current models. This simple model could be used to increase investigation into fracture healing, delayed union, and non-union.
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Affiliation(s)
- C D Collier
- Department of Orthopaedics, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA
| | - B S Hausman
- Department of Orthopaedics, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA
| | - S H Zulqadar
- Department of Orthopaedics, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA
| | - E S Din
- Department of Orthopaedics, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA
| | - J M Anderson
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - O Akkus
- Department of Orthopaedics, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA.,Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | - E M Greenfield
- Department of Orthopaedics, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA.,Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
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18
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Kadakia RJ, Devereaux EJ, Ahn H, Traub BC, Kephart D, Willett NJ, Bariteau JT. Development of a Small Animal Ankle Arthrodesis Model. Foot Ankle Int 2020; 41:101-108. [PMID: 31910053 DOI: 10.1177/1071100719873900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Our understanding of the biology of ankle arthrodesis is based largely on work in spine and long bone animal models. However, the local soft tissue and vascular anatomy of the foot and ankle is different from that of the spine. Accordingly, the objective of this study was to develop a small animal ankle arthrodesis model. METHODS A total of 12 Lewis rats successfully underwent ankle arthrodesis with stabilization consisting of a single Kirschner wire across the prepared tibiotalar joint. Based on high nonunion rates with this initial procedure, a modification was made consisting of a second pin crossing the joint. A total of 6 rats underwent the second procedure. Radiographs were taken postoperatively and in 2-week intervals up to 10 weeks. Micro computed tomography (µCT) and histological analysis was conducted at 10 weeks to assess the fusion mass. Osseous bridging of greater than 50% across the tibiotalar joint was deemed a successful fusion. RESULTS µCT analysis determined that 11 of the 12 rats in the single-pin cohort developed nonunions (8.3% fusion rate). In the dual-pin cohort, all 6 animals successfully fused (100% fusion rate). Histological analysis supported the radiographic imaging conclusions. CONCLUSION While the initial procedure had a high nonunion rate, enhancing the stability of the fixation greatly increased the union rate. CLINICAL RELEVANCE The present work demonstrates the first reliable small animal ankle arthrodesis model. We believe that this model can be used in the development of novel therapies aimed at decreasing complications and increasing fusion rates.
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Affiliation(s)
- Rishin J Kadakia
- Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | | | - Hyunhee Ahn
- The Atlanta Veterans Affairs Medical Center, Decatur, GA, USA
| | - Brian C Traub
- Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Donald Kephart
- Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Nick J Willett
- Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA, USA.,The Atlanta Veterans Affairs Medical Center, Decatur, GA, USA
| | - Jason T Bariteau
- Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA, USA
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19
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Greising SM, Corona BT, McGann C, Frankum JK, Warren GL. Therapeutic Approaches for Volumetric Muscle Loss Injury: A Systematic Review and Meta-Analysis. TISSUE ENGINEERING PART B-REVIEWS 2019; 25:510-525. [PMID: 31578930 DOI: 10.1089/ten.teb.2019.0207] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Our goal was to understand the impact of regenerative therapies on the functional capacity of skeletal muscle following volumetric muscle loss (VML) injury. An extensive database search (e.g., PubMed, Cochrane Library, and ClinicalTrials.gov) was conducted up through January 2019 to evaluate the following: "In humans or animals with VML injury, is treatment better than no treatment at recovering functional capacity?" Study eligibility criteria required studies to have both an untreated and at least one treated VML injury group. From 2312 study reports, 44 studies met the inclusion criteria. Quantitative functional capacity data (absolute and/or normalized strength) or proportional measures (histological analysis quantifying viable muscle tissue, mitochondrial function, and/or exhaustive treadmill running) were extracted for use. While both human and animal studies were included in the searches, only animal studies met the eligibility criteria. Using a random-effects model, Hedges' g was used as the effect size (ES) and calculated such that a positive ES indicated treatment efficacy. The overall ES was 0.75 (95% confidence interval: 0.53-0.96; p < 0.0000001), indicating that the treatments, on average, resulted in a significant improvement in functional capacity. From network meta-analyses, it was determined that an acellular biomaterial combined with stem and/or progenitor cells had the greatest treatment effectiveness. The findings indicate that various treatments in animal models of VML improve the functional capacity of muscle compared to leaving the injury untreated; however, the ∼16% beneficial effect is small. Our results suggest that current regenerative therapy paradigms require further maturation to achieve clinically meaningful improvements in the functional capacity of the muscle. Impact Statement Our most salient findings are that (1) various treatment approaches used in animal models of volumetric muscle loss (VML) injury improve functional capacity compared to leaving the injury untreated and (2) an acellular biomaterial in combination with cellular components was the most effective treatment to improve functional capacity following VML injury to date. The nature of our findings has substantial implications for regenerative medicine, biomedical engineering, and rehabilitative techniques currently being evaluated and developed for VML injury repair, and are pivotal to the progression of the regenerative medicine effort aimed at restoring maximal function to traumatized and disabled limbs.
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Affiliation(s)
- Sarah M Greising
- School of Kinesiology, University of Minnesota, Minneapolis, Minnesota
| | - Benjamin T Corona
- School of Medicine, Wake Forest University, Winston-Salem, North Carolina
| | - Christopher McGann
- Department of Physical Therapy, Georgia State University, Atlanta, Georgia
| | - Jeremy K Frankum
- Department of Physical Therapy, Georgia State University, Atlanta, Georgia
| | - Gordon L Warren
- Department of Physical Therapy, Georgia State University, Atlanta, Georgia
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20
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Wang Q, Pei S, Lu XL, Wang L, Wu Q. On the characterization of interstitial fluid flow in the skeletal muscle endomysium. J Mech Behav Biomed Mater 2019; 102:103504. [PMID: 31670258 DOI: 10.1016/j.jmbbm.2019.103504] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/05/2019] [Accepted: 10/17/2019] [Indexed: 10/25/2022]
Abstract
In this paper, the interstitial fluid flow in skeletal muscle endomysium was examined using an in-situ indentation testing in combination with theoretical modelling. The objective was to understand the transport properties of the three-dimensional and highly hierarchical muscular interstitial matrices, which play important roles in muscle-bone cross-talk and signaling during musculoskeletal development and maintenance. Gastrocnemius muscles from four 3-month old calves were harvested and subjected to a creeping test using a custom-designed device. The experiments, in combination with an anatomy-based theoretical model, were used to capture the spatial-temporal response of the skeletal muscle to external impacts. For the first time, the detailed load-induced interstitial fluid pressurization in the muscle endomyseal space was obtained. The relative contribution from the solid muscle fibers and the interstitial fluid to the temporal loading response was captured. The paper presented herein provides important information regarding the mechanical environment within the muscle tissue, which could help the future study of muscle's response to forces and its subsequent signaling to surrounding tissues in vivo.
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Affiliation(s)
- Qiuyun Wang
- Cellular Biomechanics and Sports Science Laboratory, Villanova University, 800 Lancaster Avenue, Villanova, PA, 19085, USA; Department of Mechanical Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA, 19085, USA
| | - Shaopeng Pei
- Department of Mechanical Engineering, University of Delaware, Newark, DE, 19716, USA
| | - X Lucas Lu
- Department of Mechanical Engineering, University of Delaware, Newark, DE, 19716, USA
| | - Liyun Wang
- Department of Mechanical Engineering, University of Delaware, Newark, DE, 19716, USA.
| | - Qianhong Wu
- Cellular Biomechanics and Sports Science Laboratory, Villanova University, 800 Lancaster Avenue, Villanova, PA, 19085, USA; Department of Mechanical Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA, 19085, USA.
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21
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Passipieri JA, Hu X, Mintz E, Dienes J, Baker HB, Wallace CH, Blemker SS, Christ GJ. In Silico and In Vivo Studies Detect Functional Repair Mechanisms in a Volumetric Muscle Loss Injury. Tissue Eng Part A 2019; 25:1272-1288. [PMID: 30882277 PMCID: PMC6760186 DOI: 10.1089/ten.tea.2018.0280] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 12/10/2018] [Indexed: 11/12/2022] Open
Abstract
IMPACT STATEMENT Despite medical advances, volumetric muscle loss (VML) injuries to craniofacial muscles represent an unmet clinical need. We report an implantable tissue-engineered construct that leads to substantial tissue regeneration and functional recovery in a preclinical model of VML injury that is dimensionally relevant to unilateral cleft lip repair, and a series of corresponding computational models that provide biomechanical insight into mechanism(s) responsible for the VML-induced functional deficits and recovery following tissue-engineered muscle repair implantation. This unique combined approach represents a critical first step toward establishing a crucial biomechanical basis for the development of efficacious regenerative technologies, considering the spectrum of VML injuries.
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Affiliation(s)
- Juliana A. Passipieri
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Xiao Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Ellen Mintz
- Department of Pathology, University of Virginia, Charlottesville, Virginia
| | - Jack Dienes
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Hannah B. Baker
- Wake Forest Institute for Regenerative Medicine, Wake Forest University, Winston-Salem, North Carolina
| | - C. Hunter Wallace
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Silvia S. Blemker
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia
- Department of Orthopaedic Surgery, University of Virginia, Charlottesville, Virginia
| | - George J. Christ
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
- Department of Orthopaedics, University of Virginia, Charlottesville, Virginia
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22
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Saiz AM, Gionet-Gonzales MA, Lee MA, Leach JK. Conditioning of myoblast secretome using mesenchymal stem/stromal cell spheroids improves bone repair. Bone 2019; 125:151-159. [PMID: 31102712 PMCID: PMC6589400 DOI: 10.1016/j.bone.2019.05.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 05/04/2019] [Accepted: 05/14/2019] [Indexed: 12/22/2022]
Abstract
Local muscle loss associated with open fractures remains an obstacle to functional recovery and bone healing. Muscle cells secrete bioactive myokines that elicit autocrine and paracrine effects and initiate signaling pathways for regenerating damaged muscle and bone. Mesenchymal stem/stromal cells (MSCs) are under investigation for the regeneration of both muscle and bone through their potent secretome. Compared to monodisperse cells, MSC spheroids exhibit a more complex secretome with heightened therapeutic potential. We hypothesized that the osteogenic potential of myokines would be enhanced when myoblasts were exposed to the MSC spheroid secretome. Conditioned media from MSC spheroids increased osteogenic response of MC3T3 pre-osteoblasts compared to myokines from L6 myoblasts alone. This effect was synergistically enhanced when conditioned media of MSC spheroids was serially delivered to myoblasts and then osteoprogenitor cells in vitro. We then delivered myoblast-stimulated conditioned media in the presence or absence of syngeneic rat bone marrow stromal cells (rBMSCs) from alginate hydrogels to a rat critical-sized segmental defect. We observed increased bone formation in defects treated with conditioned media compared to rBMSCs alone, while bone formation was greatest in defects treated with both conditioned media and rBMSCs over 12 weeks. This foundational study demonstrates a novel approach for capitalizing on the paracrine signaling of muscle cells to promote bone repair and provides additional evidence of the synergistic interaction between muscle and bone.
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Affiliation(s)
- Augustine M Saiz
- Department of Biomedical Engineering, University of California at Davis, Davis, CA 95616, United States of America; Department of Orthopaedic Surgery, UC Davis Health, Sacramento, CA 95817, United States of America
| | - Marissa A Gionet-Gonzales
- Department of Biomedical Engineering, University of California at Davis, Davis, CA 95616, United States of America
| | - Mark A Lee
- Department of Orthopaedic Surgery, UC Davis Health, Sacramento, CA 95817, United States of America
| | - J Kent Leach
- Department of Biomedical Engineering, University of California at Davis, Davis, CA 95616, United States of America; Department of Orthopaedic Surgery, UC Davis Health, Sacramento, CA 95817, United States of America.
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23
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Ruehle MA, Li MTA, Cheng A, Krishnan L, Willett NJ, Guldberg RE. Decorin-supplemented collagen hydrogels for the co-delivery of bone morphogenetic protein-2 and microvascular fragments to a composite bone-muscle injury model with impaired vascularization. Acta Biomater 2019; 93:210-221. [PMID: 30685477 PMCID: PMC6759335 DOI: 10.1016/j.actbio.2019.01.045] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/17/2019] [Accepted: 01/23/2019] [Indexed: 12/25/2022]
Abstract
Traumatic musculoskeletal injuries that result in bone defects or fractures often affect both bone and the surrounding soft tissue. Clinically, these types of multi-tissue injuries have increased rates of complications and long-term disability. Vascular integrity is a key clinical indicator of injury severity, and revascularization of the injury site is a critical early step of the bone healing process. Our lab has previously established a pre-clinical model of composite bone-muscle injury that exhibits impaired bone healing; however, the vascularization response in this model had not yet been investigated. Here, the early revascularization of a bone defect following composite injury is shown to be impaired, and subsequently the therapeutic potential of combined vascularization and osteoinduction was investigated to overcome the impaired regeneration in composite injuries. A decorin (DCN)-supplemented collagen hydrogel was developed as a biomaterial delivery vehicle for the co-delivery microvascular fragments (MVF), which are multicellular segments of mature vasculature, and bone morphogenetic protein-2 (BMP-2), a potent osteoinductive growth factor. We hypothesized that collagen + DCN would increase BMP-2 retention over collagen alone due to DCN's ability to sequester TGF-ß growth factors. We further hypothesized that MVF would increase both early vascularization and subsequent BMP-2-mediated bone regeneration. Contrary to our hypothesis, BMP + MVF decreased the number of blood vessels relative to BMP alone and had no effect on bone healing. However, collagen + DCN was demonstrated to be a BMP-2 delivery vehicle capable of achieving bridging in the challenging composite defect model that is comparable to that achieved with a well-established alginate-based delivery system. STATEMENT OF SIGNIFICANCE: We have previously established a model of musculoskeletal trauma that exhibits impaired bone healing. For the first time, this work shows that the early revascularization response is also significantly, albeit modestly, impaired. A decorin-supplemented collagen hydrogel was used for the first time in vivo as a delivery vehicle for both a cell-based vascular therapeutic, MVF, and an osteoinductive growth factor, BMP-2. While MVF did not improve vascular volume or bone healing, collagen + DCN is a BMP-2 delivery vehicle capable of achieving bridging in the challenging composite defect model. Based on its support of robust angiogenesis in vitro, collagen + DCN may be extended for future use with other vascular therapeutics such as pre-formed vascular networks.
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Affiliation(s)
- Marissa A Ruehle
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Mon-Tzu Alice Li
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Albert Cheng
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Laxminarayanan Krishnan
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Nick J Willett
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA; Department of Orthopedics, Emory University, Atlanta, GA, USA; Research Service, Atlanta VA Medical Center, Decatur, GA, USA
| | - Robert E Guldberg
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR, USA.
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24
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Abstract
Tissue engineering in orthopaedic trauma is needed. Progress has been made in all areas including regenerating bone, cartilage, soft tissue, and making up for bone defects with scaffolds. Bone regeneration and managing bone defects with scaffolds continue to be successful in the basic science realm with promising results, but currently, these successes are mostly limited to small animal models. Cartilage defects have more clinically available treatment options, but the benefits of "off-the-shelf" allograft options, and scaffolds, have little clinical evidence in the acute fracture setting. Most of the true chondrocyte replacement therapies such as matrix-induced autologous chondrocyte implantation and osteochondral allografts require delayed treatment while cell growth or graft matching occurs. Soft-tissue defects can be managed with tissue engineering for the skin with success, but muscle and nerve defects are still limited to the basic science arena. Although significant gains have been made in all areas for tissue engineering in basic science, and is very promising, this success currently comes with limited translation into clinical availability for the orthopaedic trauma patient.
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25
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Ruehle MA, Krishnan L, Vantucci CE, Wang Y, Stevens HY, Roy K, Guldberg RE, Willett NJ. Effects of BMP-2 dose and delivery of microvascular fragments on healing of bone defects with concomitant volumetric muscle loss. J Orthop Res 2019; 37:553-561. [PMID: 30648751 DOI: 10.1002/jor.24225] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 01/11/2019] [Indexed: 02/04/2023]
Abstract
Traumatic composite bone-muscle injuries, such as open fractures, often require multiple surgical interventions and still typically result in long-term disability. Clinically, a critical indicator of composite injury severity is vascular integrity; vascular damage alone is sufficient to assign an open fracture to the most severe category. Challenging bone injuries are often treated with bone morphogenetic protein 2 (BMP-2), an osteoinductive growth factor, delivered on collagen sponge. Previous studies in a composite defect model found that a minimally bridging dose in the segmental defect model was unable to overcome concomitant muscle damage, but the effect of BMP dose on composite injuries has not yet been studied. Here, we test the hypotheses that BMP-2-mediated functional regeneration of composite extremity injuries is dose dependent and can be further enhanced via co-delivery of adipose-derived microvascular fragments (MVF), which have been previously shown to increase tissue vascular volume. Although MVF did not improve healing outcomes, we observed a significant BMP-2 dose-dependent increase in regenerated bone volume and biomechanical properties. This is the first known report of an increased BMP-2 dose improving bone healing with concomitant muscle damage. While high dose BMP-2 delivery can induce heterotopic ossification (HO) and increased inflammation, the maximum 10 μg dose used in this study did not result in HO and was associated with a lower circulating inflammatory cytokine profile than the low dose (2.5 μg) group. These data support the potential benefits of an increased, though still moderate, BMP-2 dose for treatment of bone defects with concomitant muscle damage. Published 2019. This article is a U.S. Government work and is in the public domain in the USA. J Orthop Res.
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Affiliation(s)
- Marissa A Ruehle
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| | - Laxminarayanan Krishnan
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Casey E Vantucci
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| | - Yuyan Wang
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Hazel Y Stevens
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Krishnendu Roy
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| | - Robert E Guldberg
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, Oregon
| | - Nick J Willett
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia.,Research Service, Atlanta VA Medical Center, Decatur, Georgia.,Division of Orthopaedics, Emory University School of Medicine, 1670 Clairmont Rd, Room 5A125, Decatur 30033, Georgia
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26
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Subbiah R, Guldberg RE. Materials Science and Design Principles of Growth Factor Delivery Systems in Tissue Engineering and Regenerative Medicine. Adv Healthc Mater 2019; 8:e1801000. [PMID: 30398700 DOI: 10.1002/adhm.201801000] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 09/13/2018] [Indexed: 01/22/2023]
Abstract
Growth factors (GFs) are signaling molecules that direct cell development by providing biochemical cues for stem cell proliferation, migration, and differentiation. GFs play a key role in tissue regeneration, but one major limitation of GF-based therapies is dosage-related adverse effects. Additionally, the clinical applications and efficacy of GFs are significantly affected by the efficiency of delivery systems and other pharmacokinetic factors. Hence, it is crucial to design delivery systems that provide optimal activity, stability, and tunable delivery for GFs. Understanding the physicochemical properties of the GFs and the biomaterials utilized for the development of biomimetic GF delivery systems is critical for GF-based regeneration. Many different delivery systems have been developed to achieve tunable delivery kinetics for single or multiple GFs. The identification of ideal biomaterials with tunable properties for spatiotemporal delivery of GFs is still challenging. This review characterizes the types, properties, and functions of GFs, the materials science of widely used biomaterials, and various GF loading strategies to comprehensively summarize the current delivery systems for tunable spatiotemporal delivery of GFs aimed for tissue regeneration applications. This review concludes by discussing fundamental design principles for GF delivery vehicles based on the interactive physicochemical properties of the proteins and biomaterials.
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Affiliation(s)
- Ramesh Subbiah
- Parker H. Petit Institute for Bioengineering and Bioscience; George W. Woodruff School of Mechanical Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Robert E. Guldberg
- Parker H. Petit Institute for Bioengineering and Bioscience; George W. Woodruff School of Mechanical Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
- Phil and Penny Knight Campus for Accelerating Scientific Impact; 6231 University of Oregon; Eugene OR 97403 USA
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27
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Abstract
Tendons connect muscle to bone and play an integral role in bone and joint alignment and loading. Tendons act as pulleys that provide anchorage of muscle forces for joint motion and stability, as well as for fracture reduction and realignment. Patients that experience complex fractures also have concomitant soft tissue injuries, such as tendon damage or rupture. Tendon injuries that occur at the time of bone fracture have long-term ramifications on musculoskeletal health, yet these injuries are often disregarded in clinical treatment and diagnosis for patients with bone fractures as well as in basic science approaches for understanding bone repair processes. Delayed assessment of soft tissue injuries during evaluation of trauma can lead to chronic pain, dysfunction, and delayed bone healing even following successful fracture repair, highlighting the importance of identifying and treating damaged tendons early. Treatment strategies for bone repair, such as mechanical stabilization and biological therapeutics, can impact tendon healing and function. Because poor tendon healing following complex fracture can significantly impact the function of tendon during bone fracture healing, a need exists to understand the healing process of complex fractures more broadly, beyond the healing of bone. In this review, we explored the mechanical and biological interaction of bone and tendon in the context of complex fracture, as well as the relevance and potential ramifications of tendon damage following bone fracture, which has particular impact on patients that experience complex fractures, such as from combat, automobile accidents, and other trauma.
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Affiliation(s)
- Elahe Ganji
- Department of Biomedical Engineering, University of Delaware, Newark, Delaware 19716
- Department of Mechanical Engineering, University of Delaware, Newark, Delaware 19716
| | - Megan L. Killian
- Department of Biomedical Engineering, University of Delaware, Newark, Delaware 19716
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28
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Ho SS, Hung BP, Heyrani N, Lee MA, Leach JK. Hypoxic Preconditioning of Mesenchymal Stem Cells with Subsequent Spheroid Formation Accelerates Repair of Segmental Bone Defects. Stem Cells 2018; 36:1393-1403. [PMID: 29968952 PMCID: PMC6125201 DOI: 10.1002/stem.2853] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 03/24/2018] [Accepted: 04/13/2018] [Indexed: 12/25/2022]
Abstract
Cell-based approaches for musculoskeletal tissue repair are limited by poor cell survival and engraftment. Short-term hypoxic preconditioning of mesenchymal stem cells (MSCs) can prolong cell viability in vivo, while the aggregation of MSCs into spheroids increases cell survival, trophic factor secretion, and tissue formation in vivo. We hypothesized that preconditioning MSCs in hypoxic culture before spheroid formation would increase cell viability, proangiogenic potential, and resultant bone repair compared with that of individual MSCs. Human MSCs were preconditioned in 1% O2 in monolayer culture for 3 days (PC3) or kept in ambient air (PC0), formed into spheroids of increasing cell density, and then entrapped in alginate hydrogels. Hypoxia-preconditioned MSC spheroids were more resistant to apoptosis than ambient air controls and this response correlated with duration of hypoxia exposure. Spheroids of the highest cell density exhibited the greatest osteogenic potential in vitro and vascular endothelial growth factor (VEGF) secretion was greatest in PC3 spheroids. PC3 spheroids were then transplanted into rat critical-sized femoral segmental defects to evaluate their potential for bone healing. Spheroid-containing gels induced significantly more bone healing compared with gels containing preconditioned individual MSCs or acellular gels. These data demonstrate that hypoxic preconditioning represents a simple approach for enhancing the therapeutic potential of MSC spheroids when used for bone healing. Stem Cells 2018;36:1393-1403.
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Affiliation(s)
- Steve S. Ho
- Department of Biomedical Engineering, University of California, Davis, Davis CA 95616
| | - Ben P. Hung
- Department of Biomedical Engineering, University of California, Davis, Davis CA 95616
| | - Nasser Heyrani
- Department of Orthopaedic Surgery, UC Davis Health, Sacramento CA 95817
| | - Mark A. Lee
- Department of Orthopaedic Surgery, UC Davis Health, Sacramento CA 95817
| | - J. Kent Leach
- Department of Biomedical Engineering, University of California, Davis, Davis CA 95616
- Department of Orthopaedic Surgery, UC Davis Health, Sacramento CA 95817
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29
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Sarrafian TL, Bodine SC, Murphy B, Grayson JK, Stover SM. Extracellular matrix scaffolds for treatment of large volume muscle injuries: A review. Vet Surg 2018; 47:524-535. [PMID: 29603757 DOI: 10.1111/vsu.12787] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 10/11/2017] [Accepted: 11/03/2017] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Large muscular or musculotendinous defects present a dilemma because of the inadequacies of current treatment strategies. Extracellular matrices (ECM) are potential clinically applicable regenerative biomaterials. This review summarizes information from the preclinical literature evaluating the use of ECM for muscle regeneration in animal models of volumetric muscle loss (VML). STUDY DESIGN Literature review. SAMPLE POPULATION Animal models of VML in which surgical repair was performed with an ECM product, with or without added cell populations. METHODS PubMed, Google Scholar, CAB abstracts, and Scopus were searched for preclinical studies using ECM in animal models of VML. The search terms "extracellular matrix," "VML," "muscle regeneration," "cell seeded," and "scaffold" identified 40 articles that met inclusion criteria of an animal model of VML in which surgical repair was performed with an ECM product, with or without added cell populations. Key skeletal muscle repair mechanisms and experimental findings on scaffold type, VML location, and experimental animal species were summarized. CONCLUSIONS Satellite cells and basal lamina are key endogenous contributors to skeletal muscle regeneration. ECM as a dynamic tissue component may provide structural integrity, signaling molecules, and a 3-dimensional topography conducive to muscle regeneration. Preclinical models of muscle repair most commonly used mice and rats (88%). Most experimental lesions were created in abdominal wall (33%), anterior tibialis (33%), latissimus dorsi (10%), or quadriceps (10%) muscles. Matrices varied markedly in source and preparation. Experimental outcomes of ECM and cell-seeded ECM implantation for muscle regeneration in VML were highly variable and dependent on matrix tissue source, preparation method, and anatomic site of injury. Scar tissue formation likely contributes to load transfer. Nonappendicular lesions had better regenerative results compared with appendicular VML. CLINICAL SIGNIFICANCE The preponderance of current evidence supports the use of ECM for muscle defect repair only in specific instances, such as nonappendicular and/or partial-thickness defects. Consequently, clinical use of ECM in veterinary patients requires careful consideration of the specific ECM product, lesion size and location, and loading circumstances.
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Affiliation(s)
- Tiffany L Sarrafian
- J. D. Wheat Veterinary Orthopedic Research Laboratory, University of California, Davis, Davis, California.,Clinical Investigation Facility, David Grant US Air Force Medical Center, Travis Air Force Base, Fairfield, California
| | - Sue C Bodine
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, Davis, California
| | - Brian Murphy
- J. D. Wheat Veterinary Orthopedic Research Laboratory, University of California, Davis, Davis, California
| | - J Kevin Grayson
- Clinical Investigation Facility, David Grant US Air Force Medical Center, Travis Air Force Base, Fairfield, California
| | - Susan M Stover
- J. D. Wheat Veterinary Orthopedic Research Laboratory, University of California, Davis, Davis, California
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30
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Corona BT, Flanagan KE, Brininger CM, Goldman SM, Call JA, Greising SM. Impact of volumetric muscle loss injury on persistent motoneuron axotomy. Muscle Nerve 2018; 57:799-807. [PMID: 29144551 DOI: 10.1002/mus.26016] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/12/2017] [Accepted: 11/14/2017] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Volumetric muscle loss (VML) occurs following significant traumatic injury or surgical removal of skeletal muscle, resulting in nonrecoverable loss of tissue and long-term dysfunction. Perhaps less recognized is that VML injuries inherently disrupt the neuromuscular unit, resulting in fiber denervation and presumptive motor unit rearrangement, expansion, and/or loss. To characterize neural dysfunction we quantified motoneuron axotomy, in efforts to understand how this relates to the temporal coordination of neuromuscular and morphological alterations due to injury. METHODS In an established rat tibialis anterior (TA) VML injury model, we examined the motoneuron, skeletal muscle, and maximal isometric torque at 3, 7, 14, and 21 days postinjury. RESULTS Significant axotomy of 57-79% of all TA muscle motoneurons was observed through 21 days postinjury, which was coupled with a 45-90% TA maximal torque deficit. DISCUSSION A ∼20% partial ablation of the TA muscle causes disproportionate damage across the motor unit acutely postinjury. Muscle Nerve 57: 799-807, 2018.
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Affiliation(s)
- Benjamin T Corona
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, Texas, 78234, USA
| | - Kate E Flanagan
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, Texas, 78234, USA
| | - Christian M Brininger
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, Texas, 78234, USA
| | - Stephen M Goldman
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, Texas, 78234, USA
| | - Jarrod A Call
- Department of Kinesiology, University of Georgia, Athens, Georgia, USA.,Regenerative Bioscience Center, University of Georgia, Athens, Georgia, USA
| | - Sarah M Greising
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, Texas, 78234, USA
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31
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Corona BT, Rivera JC, Greising SM. Inflammatory and Physiological Consequences of Debridement of Fibrous Tissue after Volumetric Muscle Loss Injury. Clin Transl Sci 2017; 11:208-217. [PMID: 29193769 PMCID: PMC5867018 DOI: 10.1111/cts.12519] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 10/08/2017] [Indexed: 02/06/2023] Open
Abstract
Volumetric muscle loss (VML) injuries present chronic loss of muscle fibers followed by expansive fibrotic tissue deposition. Regenerative medicine therapies are under development to promote regeneration. However, mitigation of the expansive fibrous tissue is required for integration with the remaining muscle. Using a porcine VML model, delayed debridement of injury fibrosis was performed 3 months post‐VML and observed for an additional 4 weeks. A second group underwent the initial VML and was observed for 4 weeks, allowing comparison of initial fibrosis formation and debrided groups. The following salient observations were made: (i) debridement neither exacerbated nor ameliorated strength deficits; (ii) debridement results in recurrent fibrotic tissue deposition of a similar magnitude and composition as acute VML injury; and (iii) similarly upregulated transcriptional fibrotic and transcriptional pathways persist 4 weeks after initial VML or delayed debridement. This highlights the need for future studies to investigate adjunctive antifibrotic treatments for the fibrosed musculature.
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Affiliation(s)
- Benjamin T Corona
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Jessica C Rivera
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Sarah M Greising
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
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32
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Corona BT, Rivera JC, Wenke JC, Greising SM. Tacrolimus as an adjunct to autologous minced muscle grafts for the repair of a volumetric muscle loss injury. J Exp Orthop 2017; 4:36. [PMID: 29127611 PMCID: PMC5681453 DOI: 10.1186/s40634-017-0112-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 10/20/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Volumetric muscle loss (VML) following extremity orthopaedic trauma or surgery results in chronic functional deficits and disability. A current translational approach to address the devastating functional limitations due to VML injury is the use of an autologous minced muscle graft (~1 mm3 pieces of muscle tissue) replacement into the injured defect area, although limitations related to donor site morbidity are still unaddressed. This study was designed to explore adjunct pharmacological immunomodulation to enhance graft efficacy and promote muscle function following VML injury, and thereby reduce the amount of donor tissue required. FINDINGS Using a validated VML porcine injury model in which 20% of the muscle volume was surgically removed, this study examined muscle function over 3 months post-VML injury. In vivo isometric torque of the peroneus teritus (PT) muscle was not different before surgery among sham, non-repaired, non-repaired with tacrolimus, graft-repaired, and graft-repaired with tacrolimus VML groups. Bi-weekly torque analysis of the VML injured musculature presented a significant strength deficit of ~26% compared to pre-injury in the non-repaired, non-repaired with tacrolimus, and graft-repaired groups. Comparatively, the strength deficit in the graft-repair with systemic tacrolimus was marginally improved (~19%; p = 0.056). Both of the minced graft repaired groups presented a greater proportion of muscle tissue in full-thickness histology specimen. CONCLUSIONS We demonstrate that adjunctive use of tacrolimus with an ~50% minced muscle graft replacement resulted in modest improvements in muscle function 3 months after injury and repair, but the magnitude of improvement is not expected to elicit clinically meaningful functional improvements.
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Affiliation(s)
- Benjamin T Corona
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Jessica C Rivera
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Joseph C Wenke
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Sarah M Greising
- Extremity Trauma and Regenerative Medicine Task Area, United States Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA.
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Li MT, Ruehle MA, Stevens HY, Servies N, Willett NJ, Karthikeyakannan S, Warren GL, Guldberg RE, Krishnan L. * Skeletal Myoblast-Seeded Vascularized Tissue Scaffolds in the Treatment of a Large Volumetric Muscle Defect in the Rat Biceps Femoris Muscle. Tissue Eng Part A 2017; 23:989-1000. [PMID: 28372522 DOI: 10.1089/ten.tea.2016.0523] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
High velocity impact injuries can often result in loss of large skeletal muscle mass, creating defects devoid of matrix, cells, and vasculature. Functional regeneration within these regions of large volumetric muscle loss (VML) continues to be a significant clinical challenge. Large cell-seeded, space-filling tissue-engineered constructs that may augment regeneration require adequate vascularization to maintain cell viability. However, the long-term effect of improved vascularization and the effect of addition of myoblasts to vascularized constructs have not been determined in large VMLs. Here, our objective was to create a new VML model, consisting of a full-thickness, single muscle defect, in the rat biceps femoris muscle, and evaluate the ability of myoblast-seeded vascularized collagen hydrogel constructs to augment VML regeneration. Adipose-derived microvessels were cultured with or without myoblasts to form vascular networks within collagen constructs. In the animal model, the VML injury was created in the left hind limb, and treated with the harvested autograft itself, constructs with microvessel fragments (MVF) only, constructs with microvessels and myoblasts (MVF+Myoblasts), or left empty. We evaluated the formation of vascular networks in vitro by light microscopy, and the capacity of vascularized constructs to augment early revascularization and muscle regeneration in the VML using perfusion angiography and creatine kinase activity, respectively. Myoblasts (Pax7+) were able to differentiate into myotubes (sarcomeric myosin MF20+) in vitro. The MVF+Myoblast group showed longer and more branched microvascular networks than the MVF group in vitro, but showed similar overall defect site vascular volumes at 2 weeks postimplantation by microcomputed tomography angiography. However, a larger number of small-diameter vessels were observed in the vascularized construct-treated groups. Yet, both vascularized implant groups showed primarily fibrotic tissue with adipose infiltration, poor maintenance of tissue volume within the VML, and little muscle regeneration. These data suggest that while vascularization may play an important supportive role, other factors besides adequate vascularity may determine the fate of regenerating volumetric muscle defects.
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Affiliation(s)
- Mon-Tzu Li
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia .,2 Department of Biomedical Engineering, Emory University , Atlanta, Georgia
| | - Marissa A Ruehle
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia .,2 Department of Biomedical Engineering, Emory University , Atlanta, Georgia
| | - Hazel Y Stevens
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia
| | - Nick Servies
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia
| | - Nick J Willett
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia .,2 Department of Biomedical Engineering, Emory University , Atlanta, Georgia .,3 Department of Orthopaedics, Atlanta Veteran's Affairs Medical Center , Decatur, Georgia
| | - Sukhita Karthikeyakannan
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia
| | - Gordon L Warren
- 4 Department of Physical Therapy, Georgia State University , Atlanta, Georgia
| | - Robert E Guldberg
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia
| | - Laxminarayanan Krishnan
- 1 Georgia Institute of Technology, Petit Institute for Bioengineering and Biosciences , Atlanta, Georgia
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Hurtgen BJ, Ward CL, Leopold Wager CM, Garg K, Goldman SM, Henderson BEP, McKinley TO, Greising SM, Wenke JC, Corona BT. Autologous minced muscle grafts improve endogenous fracture healing and muscle strength after musculoskeletal trauma. Physiol Rep 2017; 5:e13362. [PMID: 28747511 PMCID: PMC5532491 DOI: 10.14814/phy2.13362] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 06/26/2017] [Accepted: 06/27/2017] [Indexed: 12/18/2022] Open
Abstract
The deleterious impact of concomitant muscle injury on fracture healing and limb function is commonly considered part of the natural sequela of orthopedic trauma. Recent reports suggest that heightened inflammation in the surrounding traumatized musculature is a primary determinant of fracture healing. Relatedly, there are emerging potential therapeutic approaches for severe muscle trauma (e.g., volumetric muscle loss [VML] injury), such as autologous minced muscle grafts (1 mm3 pieces of muscle; GRAFT), that can partially prevent chronic functional deficits and appear to have an immunomodulatory effect within VML injured muscle. The primary goal of this study was to determine if repair of VML injury with GRAFT rescues impaired fracture healing and improves the strength of the traumatized muscle in a male Lewis rat model of tibia open fracture. The most salient findings of the study were: (1) tibialis anterior (TA) muscle repair with GRAFT improved endogenous healing of fractured tibia and improved the functional outcome of muscle regeneration; (2) GRAFT repair attenuated the monocyte/macrophage (CD45+CDllb+) and T lymphocyte (CD3+) response to VML injury; (3) TA muscle protein concentrations of MCP1, IL-10, and IGF-1 were augmented in a proregenerative manner by GRAFT repair; (4) VML injury concomitant with osteotomy induced a heightened systemic presence of alarmins (e.g., soluble RAGE) and leukocytes (e.g., monocytes), and depressed IGF-1 concentration, which GRAFT repair ameliorated. Collectively, these data indicate that repair of VML injury with a regenerative therapy can modulate the inflammatory and regenerative phenotype of the treated muscle and in association improve musculoskeletal healing.
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Affiliation(s)
- Brady J Hurtgen
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Catherine L Ward
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Chrissy M Leopold Wager
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Koyal Garg
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Stephen M Goldman
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Beth E P Henderson
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Todd O McKinley
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Sarah M Greising
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Joseph C Wenke
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Benjamin T Corona
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, Texas
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Hurtgen BJ, Henderson BEP, Ward CL, Goldman SM, Garg K, McKinley TO, Greising SM, Wenke JC, Corona BT. Impairment of early fracture healing by skeletal muscle trauma is restored by FK506. BMC Musculoskelet Disord 2017; 18:253. [PMID: 28606129 PMCID: PMC5469075 DOI: 10.1186/s12891-017-1617-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 06/02/2017] [Indexed: 12/21/2022] Open
Abstract
Background Heightened local inflammation due to muscle trauma or disease is associated with impaired bone regeneration. Methods We hypothesized that FK506, an FDA approved immunomodulatory compound with neurotrophic and osteogenic effects, will rescue the early phase of fracture healing which is impaired by concomitant muscle trauma in male (~4 months old) Lewis rats. FK506 (1 mg/kg; i.p.) or saline was administered systemically for 14 days after an endogenously healing tibia osteotomy was created and fixed with an intermedullary pin, and the overlying tibialis anterior (TA) muscle was either left uninjured or incurred volumetric muscle loss injury (6 mm full thickness biopsy from middle third of the muscle). Results The salient observations of this study were that 1) concomitant TA muscle trauma impaired recovery of tibia mechanical properties 28 days post-injury, 2) FK506 administration rescued the recovery of tibia mechanical properties in the presence of concomitant TA muscle trauma but did not augment mechanical recovery of an isolated osteotomy (no muscle trauma), 3) T lymphocytes and macrophage presence within the traumatized musculature were heightened by trauma and attenuated by FK506 3 days post-injury, and 4) T lymphocyte but not macrophage presence within the fracture callus were attenuated by FK506 at 14 days post-injury. FK506 did not improve TA muscle isometric torque production Conclusion Collectively, these findings support the administration of FK506 to ameliorate healing of fractures with severe muscle trauma comorbidity. The results suggest one potential mechanism of action is a reduction in local T lymphocytes within the injured musculoskeletal tissue, though other mechanisms to include direct osteogenic effects of FK506 require further investigation. Electronic supplementary material The online version of this article (doi:10.1186/s12891-017-1617-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Brady J Hurtgen
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Beth E P Henderson
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Catherine L Ward
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Stephen M Goldman
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Koyal Garg
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Todd O McKinley
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Sarah M Greising
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Joseph C Wenke
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA
| | - Benjamin T Corona
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX, 78234, USA.
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Decellularized extracellular matrix repair of volumetric muscle loss injury impairs adjacent bone healing in a rat model of complex musculoskeletal trauma. J Trauma Acute Care Surg 2017; 81:S184-S190. [PMID: 27533905 DOI: 10.1097/ta.0000000000001212] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Traumatic muscle loss (i.e., volumetric muscle loss [VML] injury) impairs adjacent fracture healing but is often left untreated. A promising therapy for this application is a decellularized extracellular matrix (ECM) because of their capacity to regenerate a vascularized tissue bed. This study tested the hypothesis that repair of VML concomitant to fracture with a small intestine submucosa (SIS)-ECM improves musculoskeletal healing. METHODS In male Lewis rats (~375 g), a 3-mm segmental bone defect (SBD) was created in concomitance with a 6-mm, full-thickness VML injury to the adjacent tibialis anterior (TA) muscle. For all rats (n = 10), the SBD was treated with internal plate fixation and delivery of recombinant human bone morphogenetic protein 2 (1 μg) on a collagen sponge. The VML either had no repair or SIS-ECM repair (n = 5/group). Bone regeneration within the SBD (BV/TV [bone volume as a fraction of total volume]) was assessed via in vivo micro-computed tomography at 2, 4, and 6 weeks and histology at 6 weeks after injury. Tibialis anterior muscle in vivo strength and histologic assessments were performed at 6 weeks after injury. RESULTS Compared with no repair, SIS-ECM presented -21% (p = 0.09) and -27% (p = 0.004) BV/TV at 4 and 6 weeks after injury, respectively. At 6 weeks, the SBD gap length was shorter for the no repair than that for the SIS-ECM (2.64 ± 0.30 and 3.67 ± 0.41 mm, respectively; p = 0.09), whereas the distances from the end of each cortical segment to the center of the first stabilization screw were longer (1.86 ± 0.25 and 0.85 ± 0.30 mm, respectively; p = 0.035), indicating enhanced resorption in the SIS-ECM group. Both groups presented similar magnitude TA muscle strength deficits compared with their contralateral limbs (10-150 Hz: no repair, -58% to 67%; SIS-ECM, -51% to 74%). The TA muscle of the SIS-ECM group was remarkable for its presentation of fibrosis, edema, and immune cell presence. CONCLUSIONS Small intestine submucosa-ECM VML repair impaired open fracture healing and failed to improve skeletal muscle strength.
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Krishnan L, Priddy LB, Esancy C, Klosterhoff BS, Stevens HY, Tran L, Guldberg RE. Delivery vehicle effects on bone regeneration and heterotopic ossification induced by high dose BMP-2. Acta Biomater 2017; 49:101-112. [PMID: 27940197 DOI: 10.1016/j.actbio.2016.12.012] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 11/10/2016] [Accepted: 12/06/2016] [Indexed: 11/15/2022]
Abstract
Bone morphogenetic protein-2 (BMP-2), delivered on absorbable collagen sponge, is frequently used to treat bone defects. However, supraphysiological BMP-2 doses are common and often associated with complications such as heterotopic ossification and inflammation, causing pain and impaired mobility. This has prompted investigations into strategies to spatially control bone regeneration, for example growth factor delivery in appropriate scaffolds. Our objective was to investigate the spatiotemporal effects of high dose BMP-2 on bone regeneration as a function of the delivery vehicle. We hypothesized that an alginate delivery system would spatially restrict bone formation compared to a collagen sponge delivery system. In vitro, BMP-2 release was accelerated from collagen sponge compared to alginate constructs. In vivo, bone regeneration was evaluated over 12weeks in critically sized rat femoral segmental defects treated with 30μg rhBMP-2 in alginate hydrogel or collagen sponge, surrounded by perforated nanofiber meshes. Total bone volume, calculated from micro-CT reconstructions, was higher in the alginate group at 12weeks. Though bone volume within the central defect region was greater in the alginate group at 8 and 12weeks, heterotopic bone volume was similar between groups. Likewise, mechanical properties from ex vivo torsional testing were comparable between groups. Histology corroborated these findings and revealed heterotopic mineralization at 2weeks post-surgery in both groups. Overall, this study recapitulated the heterotopic ossification associated with high dose BMP-2 delivery, and demonstrated that the amount and spatial pattern of bone formation was dependent on the delivery matrix. STATEMENT OF SIGNIFICANCE Alginate hydrogel-based BMP-2 delivery has induced better spatiotemporal bone regeneration in animals, compared to clinically used collagen sponge, at lower BMP-2 doses. Lack of clear dose-response relationships for BMP-2 vis-à-vis bone regeneration has contributed to the use of higher doses clinically. We investigated the potential of the alginate system, with comparatively favorable BMP-2 release-kinetics, to reduce heterotopic ossification and promote bone regeneration, when used with a high BMP-2 dose. While defect mineralization improved with alginate hydrogel, the initial high-release phase and likely early tissue exposure to BMP-2 appeared sufficient to induce heterotopic ossification. The characterization presented here should provide the framework for future evaluations of strategies to optimize bone formation and minimize adverse effects of high dose BMP-2 therapy.
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Affiliation(s)
- Laxminarayanan Krishnan
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Lauren B Priddy
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Camden Esancy
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Brett S Klosterhoff
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA; George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Hazel Y Stevens
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, Atlanta, GA 30332, USA
| | - Lisa Tran
- Department of Surgery, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Robert E Guldberg
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332, USA; George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, Atlanta, GA 30332, USA.
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Greising SM, Dearth CL, Corona BT. Regenerative and Rehabilitative Medicine: A Necessary Synergy for Functional Recovery from Volumetric Muscle Loss Injury. Cells Tissues Organs 2016; 202:237-249. [PMID: 27825146 DOI: 10.1159/000444673] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2016] [Indexed: 01/04/2023] Open
Abstract
Volumetric muscle loss (VML) is a complex and heterogeneous problem due to significant traumatic or surgical loss of skeletal muscle tissue. The consequences of VML are substantial functional deficits in joint range of motion and skeletal muscle strength, resulting in life-long dysfunction and disability. Traditional physical medicine and rehabilitation paradigms do not address the magnitude of force loss due to VML and related musculoskeletal comorbidities. Recent advancements in regenerative medicine have set forth encouraging and emerging therapeutic options for VML injuries. There is significant potential that combined rehabilitative and regenerative therapies can restore limb and muscle function following VML injury in a synergistic manner. This review presents the current state of the VML field, spanning clinical and preclinical literature, with particular focus on rehabilitation and regenerative medicine in addition to their synergy. Moving forward, multidisciplinary collaboration between clinical and research fields is encouraged in order to continue to improve the treatment of VML injuries and specifically address the encompassing physiology, pathology, and specific needs of this patient population. This is a work of the US Government and is not subject to copyright protection in the USA. Foreign copyrights may apply. Published by S. Karger AG, Basel.
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Corona BT, Wenke JC, Ward CL. Pathophysiology of Volumetric Muscle Loss Injury. Cells Tissues Organs 2016; 202:180-188. [PMID: 27825160 DOI: 10.1159/000443925] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2016] [Indexed: 11/19/2022] Open
Abstract
Volumetric muscle loss (VML) injuries are prevalent in civilian and military trauma patients and are known to impart chronic functional deficits. The frank loss of muscle tissue that defines VML injuries is beyond the robust reparative and regenerative capacities of mammalian skeletal muscle. Given the nature of VML injuries, there is a clear need to develop therapies that promote de novo regeneration of skeletal muscle fibers, which can integrate with the remaining musculature and restore muscle strength. However, the pathophysiology of VML injuries is not completely defined, and, therefore, there may be other opportunities to improve functional outcomes other than de novo regeneration. Herein, clinical and preclinical studies of VML were reviewed to ascertain salient manifestations of VML injury that can impair limb function and muscle strength. The limited clinical data available highlighted proliferative fibrosis secondary to VML injury as a viable target to improve limb range of motion. Selected preclinical studies that used standardized neuromuscular functional assessments broadly identified that the muscle mass remaining after VML injury is performing suboptimally, and, therefore, percent VML strength deficits are significantly worse than can be explained by the initial frank loss of contractile machinery. Potential mechanisms of suboptimal strength of the remaining muscle mass suggested within the literature include intramuscular nerve damage, muscle architectural perturbations, and diminished transmission of force. Collectively, both clinical and preclinical data indicate a complex pathophysiology after VML that presents multiple therapeutic targets. This is a work of the US Government and is not subject to copyright protection in the USA. Foreign copyrights may apply. Published by S. Karger AG, Basel.
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Willett NJ, Krishnan L, Li MTA, Guldberg RE, Warren GL. Guidelines for Models of Skeletal Muscle Injury and Therapeutic Assessment. Cells Tissues Organs 2016; 202:214-226. [PMID: 27825151 DOI: 10.1159/000445345] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2016] [Indexed: 11/19/2022] Open
Abstract
Volumetric muscle loss (VML) injuries present a large clinical challenge with a significant need for new interventions. While there have been numerous reviews on muscle injury models, few have critically evaluated VML models. The objective of this review is to discuss current preclinical models of VML in terms of models, analytical outcomes, and therapeutic interventions, and to provide guidelines for the future use of preclinical VML models. This is a work of the US Government and is not subject to copyright protection in the USA. Foreign copyrights may apply. Published by S. Karger AG, Basel.
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Corona BT, Greising SM. Challenges to acellular biological scaffold mediated skeletal muscle tissue regeneration. Biomaterials 2016; 104:238-46. [DOI: 10.1016/j.biomaterials.2016.07.020] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 07/11/2016] [Accepted: 07/16/2016] [Indexed: 02/08/2023]
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McDermott AM, Mason DE, Lin ASP, Guldberg RE, Boerckel JD. Influence of structural load-bearing scaffolds on mechanical load- and BMP-2-mediated bone regeneration. J Mech Behav Biomed Mater 2016; 62:169-181. [PMID: 27208510 DOI: 10.1016/j.jmbbm.2016.05.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 05/04/2016] [Accepted: 05/05/2016] [Indexed: 01/03/2023]
Abstract
A common design constraint in functional tissue engineering is that scaffolds intended for use in load-bearing sites possess similar mechanical properties to the replaced tissue. Here, we tested the hypothesis that in vivo loading would enhance bone morphogenetic protein-2 (BMP-2)-mediated bone regeneration in the presence of a load-bearing PLDL scaffold, whose pores and central core were filled with BMP-2-releasing alginate hydrogel. First, we evaluated the effects of in vivo mechanical loading on bone regeneration in the structural scaffolds. Second, we compared scaffold-mediated bone regeneration, independent of mechanical loading, with alginate hydrogel constructs, without the structural scaffold, that have been shown previously to facilitate in vivo mechanical stimulation of bone formation. Contrary to our hypothesis, mechanical loading had no effect on bone formation, distribution, or biomechanical properties in structural scaffolds. Independent of loading, the structural scaffolds reduced bone formation compared to non-structural alginate, particularly in regions in which the scaffold was concentrated, resulting in impaired functional regeneration. This is attributable to a combination of stress shielding by the scaffold and inhibition of cellular infiltration and tissue ingrowth. Collectively, these data question the necessity of scaffold similarity to mature tissue at the time of implantation and emphasize development of an environment conducive to cellular activation of matrix production and ultimate functional regeneration.
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Affiliation(s)
- Anna M McDermott
- Department of Aerospace and Mechanical Engineering, Bioengineering Graduate Program, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Devon E Mason
- Department of Aerospace and Mechanical Engineering, Bioengineering Graduate Program, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Angela S P Lin
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Robert E Guldberg
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Joel D Boerckel
- Department of Aerospace and Mechanical Engineering, Bioengineering Graduate Program, University of Notre Dame, Notre Dame, IN 46556, USA.
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Hurtgen B, Ward C, Garg K, Pollot B, Goldman S, McKinley T, Wenke J, Corona B. Severe muscle trauma triggers heightened and prolonged local musculoskeletal inflammation and impairs adjacent tibia fracture healing. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2016; 16:122-34. [PMID: 27282456 PMCID: PMC5114355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
OBJECTIVES Complicated fracture healing is often associated with the severity of surrounding muscle tissue trauma. Since inflammation is a primary determinant of musculoskeletal health and regeneration, it is plausible that delayed healing and non-unions are partly caused by compounding local inflammation in response to concomitant muscle trauma. METHODS AND RESULTS To investigate this possibility, a Lewis rat open fracture model [tibia osteotomy with adjacent tibialis anterior (TA) muscle volumetric muscle loss (VML) injury] was interrogated. We observed that VML injury impaired tibia healing, as indicated by diminished mechanical strength and decreased mineralized bone within the fracture callus, as well as continued presence of cartilage instead of woven bone 28 days post-injury. The VML injured muscle presented innate and adaptive immune responses that were atypical of canonical muscle injury healing. Additionally, the VML injury resulted in a perturbation of the inflammatory phase of fracture healing, as indicated by elevations of CD3(+) lymphocytes and CD68+ macrophages in the fracture callus at 3 and 14d post-injury, respectively. CONCLUSIONS These data indicate that heightened and sustained innate and adaptive immune responses to traumatized muscle are associated with impaired fracture healing and may be targeted for the prevention of delayed and non-union following musculoskeletal trauma.
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Affiliation(s)
- B.J. Hurtgen
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, TX
| | - C.L. Ward
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, TX
| | - K. Garg
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, TX
| | - B.E. Pollot
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, TX
| | - S.M. Goldman
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, TX
| | - T.O. McKinley
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN
| | - J.C. Wenke
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, TX
| | - B.T. Corona
- Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, Fort Sam Houston, TX,Corresponding author: Benjamin T. Corona, Extremity Trauma and Regenerative Medicine Task Area, US Army Institute of Surgical Research, 3698 Chambers Pass, BHT1, Fort Sam Houston, TX 78234 E-mail: •
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Abstract
Volumetric muscle loss (VML) injury is prevalent in severe extremity trauma and is an emerging focus area among orthopedic and regenerative medicine fields. VML injuries are the result of an abrupt, frank loss of tissue and therefore of different etiology from other standard rodent injury models to include eccentric contraction, ischemia reperfusion, crush, and freeze injury. The current focus of many VML-related research efforts is to regenerate the lost muscle tissue and thereby improve muscle strength. Herein, we describe a VML model in the anterior compartment of the hindlimb that is permissible to repeated neuromuscular strength assessments and is validated in mouse, rat, and pig.
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Affiliation(s)
- Beth E Pollot
- Extremity Trauma and Regenerative Medicine, United States Army Institute of Surgical Research, 3698 Chambers Pass, Bldg 3611, Fort Sam Houston, TX, 78234-6315, USA
| | - Benjamin T Corona
- Extremity Trauma and Regenerative Medicine, United States Army Institute of Surgical Research, 3698 Chambers Pass, Bldg 3611, Fort Sam Houston, TX, 78234-6315, USA.
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Lampert FM, Momeni A, Filev F, Torio-Padron N, Finkenzeller G, Stark GB, Steiner D, Koulaxouzidis G. Utilization of a genetically modified muscle flap for local BMP-2 production and its effects on bone healing: a histomorphometric and radiological study in a rat model. J Orthop Surg Res 2015; 10:55. [PMID: 25924919 PMCID: PMC4424495 DOI: 10.1186/s13018-015-0196-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 03/10/2015] [Indexed: 12/20/2022] Open
Abstract
Aim of the study We developed an experimental rat model to explore the possibility of enhancing the healing of critical-size bone defects. The aim of this study was to demonstrate the feasibility of this concept by achieving high local BMP-2 expression via a transduced muscle flap that would facilitate bony union while minimizing systemic sequelae. Methods The transduction potential of the adenoviral vector encoding for BMP-2 was tested in different cell lines in vitro. In vivo experiments consisted of harvesting a pedicled quadriceps femoris muscle flap with subsequent creation of a critical-size defect in the left femur in Sprague-Dawley rats. Next, the pedicled muscle flap was perfused with high titers of Ad.BMP-2 and Ad.GFP virus, respectively. Twelve animals were divided into three groups comparing the effects of Ad.BMP-2 transduction to Ad.GFP and placebo. Bone healing was monitored radiologically with subsequent histological analysis post-mortem. Results The feasibility of this concept was demonstrated by successful transduction in vitro and in vivo as evidenced by a marked increase of BMP-2 expression. The three examined groups only showed minor difference regarding bone regeneration; however, one complete bridging of the defect was observed in the Ad.BMP-2 group. No evidence of systemic viral contamination was noted. Conclusions A marked increase of local BMP-2 expression (without untoward systemic sequelae) was detected. However, bone healing was not found to be significantly enhanced, possibly due to the small sample size of the study.
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Affiliation(s)
- Florian M Lampert
- Department of Plastic and Hand Surgery, University of Freiburg Medical Center, Hugstetterstr. 55, D-79106, Freiburg, Germany.
| | - Arash Momeni
- Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, 770 Welch Road, Suite 400, Palo Alto, CA, 94304-5715, USA.
| | - Filip Filev
- Department of Ophthalmology, University MedicalCenter Hamburg-Eppendorf, Haus West 40 (W40), Martinistr. 52, D-20246, Hamburg, Germany.
| | - Nestor Torio-Padron
- Department of Plastic and Hand Surgery, University of Freiburg Medical Center, Hugstetterstr. 55, D-79106, Freiburg, Germany.
| | - Günter Finkenzeller
- Department of Plastic and Hand Surgery, University of Freiburg Medical Center, Hugstetterstr. 55, D-79106, Freiburg, Germany.
| | - G Björn Stark
- Department of Plastic and Hand Surgery, University of Freiburg Medical Center, Hugstetterstr. 55, D-79106, Freiburg, Germany.
| | - Dominik Steiner
- Department of Plastic and Hand Surgery, University Hospital of Erlangen, Friedrich-Alexander-University of Erlangen-Nürnberg, Krankenhausstrasse 12, 91054, Erlangen, Germany.
| | - Georgios Koulaxouzidis
- Department of Plastic and Hand Surgery, University of Freiburg Medical Center, Hugstetterstr. 55, D-79106, Freiburg, Germany.
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Davis K, Griffin K, Chu TM, Wenke J, Corona B, McKinley T, Kacena M. Muscle-bone interactions during fracture healing. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2015; 15:1-9. [PMID: 25730647 PMCID: PMC4433554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Subscribe] [Scholar Register] [Accepted: 12/08/2014] [Indexed: 11/06/2022]
Abstract
Although it is generally accepted that the rate and strength of fracture healing is intimately linked to the integrity of surrounding soft tissues, the contribution of muscle has largely been viewed as a vascular supply for oxygen and nutrient exchange. However, more is becoming known about the cellular and paracrine contributions of muscle to the fracture healing process. Research has shown that muscle is capable of supplying osteoprogenitor cells in cases where the periosteum is insufficient, and the muscular osteoprogenitors possess similar osteogenic potential to those derived from the periosteum. Muscle's secrotome includes proteins capable of inhibiting or enhancing osteogenesis and myogenesis following musculoskeletal injury and can be garnered for therapeutic use in patients with traumatic musculoskeletal injuries. In this review, we will highlight the current knowledge on muscle-bone interaction in the context of fracture healing as well as concisely present the current models to study such interactions.
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Affiliation(s)
- K.M. Davis
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN
| | - K.S. Griffin
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN
| | - T-M.G. Chu
- Department of Restorative Dentistry, Indiana University School of Dentistry, Indianapolis, IN
| | - J.C. Wenke
- Extremity Trauma & Regenerative Medicine Task Area, United States Army Institute of Surgical Research, San Antonio, TX
| | - B.T. Corona
- Extremity Trauma & Regenerative Medicine Task Area, United States Army Institute of Surgical Research, San Antonio, TX
| | - T.O. McKinley
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN
| | - M.A. Kacena
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN
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Dosier CR, Uhrig BA, Willett NJ, Krishnan L, Li MTA, Stevens HY, Schwartz Z, Boyan BD, Guldberg RE. Effect of cell origin and timing of delivery for stem cell-based bone tissue engineering using biologically functionalized hydrogels. Tissue Eng Part A 2015; 21:156-65. [PMID: 25010532 PMCID: PMC4298752 DOI: 10.1089/ten.tea.2014.0057] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 06/25/2014] [Indexed: 01/14/2023] Open
Abstract
Despite progress in bone tissue engineering, the healing of critically sized diaphyseal defects remains a clinical challenge. A stem cell-based approach is an attractive alternative to current treatment techniques. The objective of this study was to examine the ability of adult stem cells to enhance bone formation when co-delivered with the osteoinductive factor bone morphogenetic protein-2 (BMP-2) in a biologically functionalized hydrogel. First, adipose and bone marrow-derived mesenchymal stem cells (ADSCs and BMMSCs) were screened for their potential to form bone when delivered in an RGD functionalized alginate hydrogel using a subcutaneous implant model. BMMSCs co-delivered with BMP-2 produced significantly more mineralized tissue compared with either ADSCs co-delivered with BMP-2 or acellular hydrogels containing BMP-2. Next, the ability of BMMSCs to heal a critically sized diaphyseal defect with a nonhealing dose of BMP-2 was tested using the alginate hydrogel as an injectable cell carrier. The effect of timing of therapeutic delivery on bone regeneration was also tested in the diaphyseal model. A 7 day delayed injection of the hydrogel into the defect site resulted in less mineralized tissue formation than immediate delivery of the hydrogel. By 12 weeks, BMMSC-loaded hydrogels produced significantly more bone than acellular constructs regardless of immediate or delayed treatment. For immediate delivery, bridging of defects treated with BMMSC-loaded hydrogels occurred at a rate of 75% compared with a 33% bridging rate for acellular-treated defects. No bridging was observed in any of the delayed delivery samples for any of the groups. Therefore, for this cell-based bone tissue engineering approach, immediate delivery of constructs leads to an overall enhanced healing response compared with delayed delivery techniques. Further, these studies demonstrate that co-delivery of adult stem cells, specifically BMMSCs, with BMP-2 enhances bone regeneration in a critically sized femoral segmental defect compared with acellular hydrogels containing BMP-2.
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Affiliation(s)
- Christopher R. Dosier
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Brent A. Uhrig
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Nick J. Willett
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Laxminarayanan Krishnan
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Mon-Tzu Alice Li
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Hazel Y. Stevens
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Zvi Schwartz
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
- VCU School of Engineering, Virginia Commonwealth University, Richmond, Virginia
| | - Barbara D. Boyan
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
- VCU School of Engineering, Virginia Commonwealth University, Richmond, Virginia
| | - Robert E. Guldberg
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
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Carlier A, van Gastel N, Geris L, Carmeliet G, Van Oosterwyck H. Size does matter: an integrative in vivo-in silico approach for the treatment of critical size bone defects. PLoS Comput Biol 2014; 10:e1003888. [PMID: 25375821 PMCID: PMC4222588 DOI: 10.1371/journal.pcbi.1003888] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 09/02/2014] [Indexed: 01/07/2023] Open
Abstract
Although bone has a unique restorative capacity, i.e., it has the potential to heal scarlessly, the conditions for spontaneous bone healing are not always present, leading to a delayed union or a non-union. In this work, we use an integrative in vivo - in silico approach to investigate the occurrence of non-unions, as well as to design possible treatment strategies thereof. The gap size of the domain geometry of a previously published mathematical model was enlarged in order to study the complex interplay of blood vessel formation, oxygen supply, growth factors and cell proliferation on the final healing outcome in large bone defects. The multiscale oxygen model was not only able to capture the essential aspects of in vivo non-unions, it also assisted in understanding the underlying mechanisms of action, i.e., the delayed vascularization of the central callus region resulted in harsh hypoxic conditions, cell death and finally disrupted bone healing. Inspired by the importance of a timely vascularization, as well as by the limited biological potential of the fracture hematoma, the influence of the host environment on the bone healing process in critical size defects was explored further. Moreover, dependent on the host environment, several treatment strategies were designed and tested for effectiveness. A qualitative correspondence between the predicted outcomes of certain treatment strategies and experimental observations was obtained, clearly illustrating the model's potential. In conclusion, the results of this study demonstrate that due to the complex non-linear dynamics of blood vessel formation, oxygen supply, growth factor production and cell proliferation and the interactions thereof with the host environment, an integrative in silico-in vivo approach is a crucial tool to further unravel the occurrence and treatments of challenging critical sized bone defects. In 5–10% of fracture patients, the bone fractures do not heal in the normal healing period (delayed healing) or do not heal at all (non-union). In order to investigate the causes of impaired healing and design potential treatment strategies, we have used a combined experimental and computational approach. More specifically, large bone defects were analyzed in mouse models and simulated by a previously published computational model. After showing that the predictions of the computational model match the observations of the experimental model, we have used the computational model to investigate the underlying mechanisms of action. In particular, the results indicated that the new blood vessels do not reach the central fracture zone in time due to the large defect size, which leads to insufficient oxygen delivery, increased cell death and disrupted bone healing. The healing, however, could be rescued by adequate blood vessel ingrowth from the overlying soft tissues. Moreover, potential treatment strategies were designed based on the influence of these soft tissues. In conclusion, this study demonstrates the potential of a combined experimental and computational approach to contribute to the understanding of pathological processes like the impaired bone regeneration in large bone defects and design future treatments thereof.
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Affiliation(s)
- Aurélie Carlier
- Biomechanics Section, KU Leuven, Leuven, Belgium
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Biomechanics Research Unit, University of Liège, Liège, Belgium
- * E-mail:
| | - Nick van Gastel
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Liesbet Geris
- Biomechanics Section, KU Leuven, Leuven, Belgium
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Biomechanics Research Unit, University of Liège, Liège, Belgium
| | - Geert Carmeliet
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Hans Van Oosterwyck
- Biomechanics Section, KU Leuven, Leuven, Belgium
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
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Lai X, Price C, Lu XL, Wang L. Imaging and quantifying solute transport across periosteum: implications for muscle-bone crosstalk. Bone 2014; 66:82-9. [PMID: 24928492 PMCID: PMC4125458 DOI: 10.1016/j.bone.2014.06.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 05/23/2014] [Accepted: 06/02/2014] [Indexed: 01/18/2023]
Abstract
Muscle and bone are known to act as a functional unit and communicate biochemically during tissue development and maintenance. Muscle-derived factors (myokines) have been found to affect bone functions in vitro. However, the transport times of myokines to penetrate into bone, a critical step required for local muscle-bone crosstalk, have not been quantified in situ or in vivo. In this study, we investigated the permeability of the periosteum, a major barrier to muscle-bone crosstalk by tracking and modeling fluorescent tracers that mimic myokines under confocal microscopy. Periosteal surface boundaries and tracer penetration within the boundaries were imaged in intact murine tibiae using reflected light and time-series xz confocal imaging, respectively. Four fluorescent tracers including sodium fluorescein (376Da) and dextrans (3kDa, 10kDa and 40kDa) were chosen because they represented a wide range of molecular weights (MW) of myokines. We found that i) murine periosteum was permeable to the three smaller tracers while the 40kDa could not penetrate beyond 40% of the outer periosteum within 8h, suggesting that periosteum is semi-permeable with a cut-off MW of approximately 40kDa, and ii) the characteristic penetration time through the periosteum (~60μm thick) increased with tracer MW and fit well with a relationship tcs=-4.43×10(4)-0.57×MWDa-4×10(4)-8.65×10(8)MWDa-4×10(4), from which, the characteristic penetration times of various myokines were extrapolated. To achieve effective muscle-bone crosstalk, likely signaling candidates should have shorter penetration time than their bioactive time, which we assumed to be 5 times of the molecule's half-lifetime in the body. Myokines such as PGE2, IGF-1, IL-15 and FGF-2 were predicted to satisfy this requirement. In summary, a novel imaging approach was developed and used to investigate the transport of myokine mimicking-tracers through the periosteum, enabling further quantitative studies of muscle-bone communication in physiologically normal and pathological conditions.
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Affiliation(s)
- Xiaohan Lai
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716, USA.
| | - Christopher Price
- Department of Biomedical Engineering, University of Delaware, Newark, DE 19716, USA.
| | - Xin Lucas Lu
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716, USA; Department of Biomedical Engineering, University of Delaware, Newark, DE 19716, USA.
| | - Liyun Wang
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716, USA; Department of Biomedical Engineering, University of Delaware, Newark, DE 19716, USA.
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Zhang D, Liu C, Zhang J, Cai D, Yang X, Li S, Zhong H. [RGD peptide-modified chitosan as a gene carrier of implant surface]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 2014; 32:336-340. [PMID: 25241532 PMCID: PMC7041066 DOI: 10.7518/hxkq.2014.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 05/20/2014] [Indexed: 06/03/2023]
Abstract
OBJECTIVE This study is conducted to explore new methods to perform surface biomodification of titanium implants and improve osteogenic efficiency. METHODS An RGD peptide and chitosan (CS) were combined by acylation reaction, forming RGD-CS. An RGD-CS/pDNA complex was subsequently prepared using a complex coacervation method and grafted on a pure titanium surface after physical and biochemical treatments were performed. The chemical structural characteristics of RGD-CS were evaluated using an infrared spectrometer and an elemental analyzer. The shape of this complex was then assessed by gel electrophoresis combined with atomic force microscopy. The grafting effect of this complex on the titanium surface was detected by EB staining. RESULTS CS and RGD peptides were coupled by an amide bond. The RGD-CS/pDNA complex was completely composited at N/P > or = 2. Atomic force microscopy results showed that the morphology of this complex was mainly spherical. EB staining experiments showed that this complex was successfully grafted on the titanium plate. CONCLUSION RGD peptide-modified CS can be used as a titanium implant surface plasmid package carrier of pDNA.
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