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Dorogin J, Hochstatter HB, Shepherd SO, Svendsen JE, Benz MA, Powers AC, Fear KM, Townsend JM, Prell JS, Hosseinzadeh P, Hettiaratchi MH. Moderate-Affinity Affibodies Modulate the Delivery and Bioactivity of Bone Morphogenetic Protein-2. Adv Healthc Mater 2023; 12:e2300793. [PMID: 37379021 PMCID: PMC10592408 DOI: 10.1002/adhm.202300793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/16/2023] [Indexed: 06/29/2023]
Abstract
Uncontrolled bone morphogenetic protein-2 (BMP-2) release can lead to off-target bone growth and other adverse events. To tackle this challenge, yeast surface display is used to identify unique BMP-2-specific protein binders known as affibodies that bind to BMP-2 with different affinities. Biolayer interferometry reveals an equilibrium dissociation constant of 10.7 nm for the interaction between BMP-2 and high-affinity affibody and 34.8 nm for the interaction between BMP-2 and the low-affinity affibody. The low-affinity affibody-BMP-2 interaction also exhibits an off-rate constant that is an order of magnitude higher. Computational modeling of affibody-BMP-2 binding predicts that the high- and low-affinity affibodies bind to two distinct sites on BMP-2 that function as different cell-receptor binding sites. BMP-2 binding to affibodies reduces expression of the osteogenic marker alkaline phosphatase (ALP) in C2C12 myoblasts. Affibody-conjugated polyethylene glycol-maleimide hydrogels increase uptake of BMP-2 compared to affibody-free hydrogels, and high-affinity hydrogels exhibit lower BMP-2 release into serum compared to low-affinity hydrogels and affibody-free hydrogels over four weeks. Loading BMP-2 into affibody-conjugated hydrogels prolongs ALP activity of C2C12 myoblasts compared to soluble BMP-2. This work demonstrates that affibodies with different affinities can modulate BMP-2 delivery and activity, creating a promising approach for controlling BMP-2 delivery in clinical applications.
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Affiliation(s)
- Jonathan Dorogin
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
| | - Henry B. Hochstatter
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
- Department of Human Physiology, University of Oregon. 1320 E 15 Ave., Eugene, OR, USA. 97403
| | - Samantha O. Shepherd
- Department of Chemistry and Biochemistry, University of Oregon. 1253 University of Oregon, Eugene, OR, USA. 97403
| | - Justin E. Svendsen
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
- Department of Chemistry and Biochemistry, University of Oregon. 1253 University of Oregon, Eugene, OR, USA. 97403
| | - Morrhyssey A. Benz
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
- Department of Chemistry and Biochemistry, University of Oregon. 1253 University of Oregon, Eugene, OR, USA. 97403
| | - Andrew C. Powers
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
| | - Karly M. Fear
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
| | - Jakob M. Townsend
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
| | - James S. Prell
- Department of Chemistry and Biochemistry, University of Oregon. 1253 University of Oregon, Eugene, OR, USA. 97403
| | - Parisa Hosseinzadeh
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
- Department of Chemistry and Biochemistry, University of Oregon. 1253 University of Oregon, Eugene, OR, USA. 97403
| | - Marian H. Hettiaratchi
- Department of Bioengineering, Knight Campus for Accelerating Scientific Impact, University of Oregon. 6231 University of Oregon, Eugene, OR, USA. 97403
- Department of Chemistry and Biochemistry, University of Oregon. 1253 University of Oregon, Eugene, OR, USA. 97403
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Liu Y, Puthia M, Sheehy EJ, Ambite I, Petrlova J, Prithviraj S, Oxborg MW, Sebastian S, Vater C, Zwingenberger S, Struglics A, Bourgine PE, O'Brien FJ, Raina DB. Sustained delivery of a heterodimer bone morphogenetic protein-2/7 via a collagen hydroxyapatite scaffold accelerates and improves critical femoral defect healing. Acta Biomater 2023; 162:164-181. [PMID: 36967054 DOI: 10.1016/j.actbio.2023.03.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 03/14/2023] [Accepted: 03/20/2023] [Indexed: 04/07/2023]
Abstract
Despite the glimmer of hope provided by the discovery and commercialization of bone morphogenetic protein-2 (BMP-2) as a bone graft substitute, side effects related to the use of supraphysiological doses have hindered its clinical usage. In this study, we compared the osteoinductive potential of BMP-2 homodimer with a heterodimer of BMP-2/7, both delivered via a collagen-hydroxyapatite (CHA) scaffold delivery system, with the aim to reduce the overall therapeutic BMP doses and the associated side-effects. We first show that the incorporation of hydroxyapatite in collagen-based BMP delivery systems is pivotal for achieving efficient BMP sequestration and controlled release. Using an ectopic implantation model, we then showed that the CHA+BMP-2/7 was more osteoinductive than CHA+BMP-2. Further evaluation of the molecular mechanisms responsible for this increased osteoinductivity at an early stage in the regeneration process indicated that the CHA+BMP-2/7 enhanced progenitor cell homing at the implantation site, upregulated the key transcriptomic determinants of bone formation, and increased the production of bone extracellular matrix components. Using fluorescently labelled BMP-2/7 and BMP-2, we demonstrated that the CHA scaffold provided a long-term delivery of both molecules for at least 20 days. Finally, using a rat femoral defect model, we showed that an ultra-low dose (0.5 µg) of BMP-2/7 accelerated fracture healing and performed at a level comparable to 20-times higher BMP-2 dose. Our results indicate that the sustained delivery of BMP-2/7 via a CHA scaffold could bring us a step closer in the quest for the use of physiological growth factor doses in fracture healing. STATEMENT OF SIGNIFICANCE: • Incorporation of hydroxyapatite (HA) in a collagen scaffold dramatically improves bone morphogenic protein (BMP) sequestration via biophysical interactions with BMP, thereby providing more controlled BMP release compared with pristine collagen. • We then investigate the molecular mechanisms responsible for increased osteoinductive potential of a heterodimer BMP-2/7 with is clinically used counterpart, the BMP-2 homodimer. • The superior osteoinductive properties of BMP-2/7 are a consequence of its direct positive effect on progenitor cell homing at the implantation site, which consequently leads to upregulation of cartilage and bone related genes and biochemical markers. • An ultra-low dose of BMP-2/7 delivered via a collagen-HA (CHA) scaffold leads to accelerated healing of a critical femoral defect in rats while a 20-times higher BMP-2 dose was required to achieve comparable results.
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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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Teal CJ, Hettiaratchi MH, Ho MT, Ortin-Martinez A, Ganesh AN, Pickering AJ, Golinski AW, Hackel BJ, Wallace VA, Shoichet MS. Directed Evolution Enables Simultaneous Controlled Release of Multiple Therapeutic Proteins from Biopolymer-Based Hydrogels. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2202612. [PMID: 35790035 DOI: 10.1002/adma.202202612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/28/2022] [Indexed: 06/15/2023]
Abstract
With the advent of increasingly complex combination strategies of biologics, independent control over their delivery is the key to their efficacy; however, current approaches are hindered by the limited independent tunability of their release rates. To overcome these limitations, directed evolution is used to engineer highly specific, low affinity affibody binding partners to multiple therapeutic proteins to independently control protein release rates. As a proof-of-concept, specific affibody binding partners for two proteins with broad therapeutic utility: insulin-like growth factor-1 (IGF-1) and pigment epithelium-derived factor (PEDF) are identified. Protein-affibody binding interactions specific to these target proteins with equilibrium dissociation constants (KD ) between 10-7 and 10-8 m are discovered. The affibodies are covalently bound to the backbone of crosslinked hydrogels using click chemistry, enabling sustained, independent, and simultaneous release of bioactive IGF-1 and PEDF over 7 days. The system is tested with C57BL/6J mice in vivo, and the affibody-controlled release of IGF-1 results in sustained activity when compared to bolus IGF-1 delivery. This work demonstrates a new, broadly applicable approach to tune the release of therapeutic proteins simultaneously and independently and thus the way for precise control over the delivery of multicomponent therapies is paved.
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Affiliation(s)
- Carter J Teal
- Institute of Biomedical Engineering, 164 College Street, Toronto, ON, M5S 3G9, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
| | - Marian H Hettiaratchi
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON, M5S 3E5, Canada
| | - Margaret T Ho
- Institute of Biomedical Engineering, 164 College Street, Toronto, ON, M5S 3G9, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
| | - Arturo Ortin-Martinez
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada
| | - Ahil N Ganesh
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON, M5S 3E5, Canada
| | - Andrew J Pickering
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON, M5S 3E5, Canada
| | - Alex W Golinski
- Department of Chemical Engineering and Materials Science, University of Minnesota-Twin Cities, 421 Washington Avenue Southeast, 356 Amundson Hall, Minneapolis, MN, 55455, USA
| | - Benjamin J Hackel
- Department of Chemical Engineering and Materials Science, University of Minnesota-Twin Cities, 421 Washington Avenue Southeast, 356 Amundson Hall, Minneapolis, MN, 55455, USA
| | - Valerie A Wallace
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, ON, M5S 1A1, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, 340 College Street, Toronto, ON, M5T 3A9, Canada
| | - Molly S Shoichet
- Institute of Biomedical Engineering, 164 College Street, Toronto, ON, M5S 3G9, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON, M5S 3E5, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, 340 College Street, Toronto, ON, M5T 3A9, Canada
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON, M5S 3H6, Canada
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Li Y, Li Y, Li L, Wang H, Wang B, Feng L, Lin S, Li G. The emerging translational potential of GDF11 in chronic wound healing. J Orthop Translat 2022; 34:113-120. [PMID: 35891714 PMCID: PMC9283991 DOI: 10.1016/j.jot.2022.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/03/2022] [Accepted: 03/12/2022] [Indexed: 11/28/2022] Open
Abstract
Chronic skin wounds impose immense suffers and economic burdens. Current research mainly focuses on acute wound management which exhibits less effective in chronic wound healing. Growth differentiation factor 11 (GDF11) has profound effects on several important physiological processes related to chronic wound healing, such as inflammation, cell proliferation, migration, angiogenesis, and neurogenesis. This review summarizes recent advances in biology of chronic wounds and the potential role of GDF11 on wound healing with its regenerative effects, as well as the potential delivery methods of GDF11. The challenges and future perspectives of GDF11-based therapy for chronic wound care are also discussed. The Translational Potential of this Article: This review summarized the significance of GDF11 in the modulation of inflammation, vascularization, cell proliferation, and remodeling, which are important physiological processes of chronic wound healing. The potential delivery methods of GDF11 in the management of chronic wound healing is also summarized. This review may provide potential therapeutic approaches based on GDF11 for chronic wound healing.
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Pearson JJ, Temenoff JS. Growth Factor Immobilization Strategies for Musculoskeletal Disorders. Curr Osteoporos Rep 2022; 20:13-25. [PMID: 35118607 PMCID: PMC10772941 DOI: 10.1007/s11914-022-00718-x] [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] [Accepted: 11/22/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE OF REVIEW Tissue regenerative solutions for musculoskeletal disorders have become increasingly important with a growing aged population. Current growth factor treatments often require high dosages with the potential for off-target effects. Growth factor immobilization strategies offer approaches towards alleviating these concerns. This review summarizes current growth factor immobilization techniques (encapsulation, affinity interactions, and covalent binding) and the effects of immobilization on growth factor loading, release, and bioactivity. RECENT FINDINGS The breadth of immobilization techniques based on encapsulation, affinity, and covalent binding offer multiple methods to improve the therapeutic efficacy of growth factors by controlling bioactivity and release. Growth factor immobilization strategies have evolved to more complex systems with the capacity to load and release multiple growth factors with spatiotemporal control. The advancements in immobilization strategies allow for development of new, complex musculoskeletal tissue treatment strategies with improved spatiotemporal control of loading, release, and bioactivity.
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Affiliation(s)
- Joseph J Pearson
- W.H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Johnna S Temenoff
- W.H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Drive, Atlanta, GA, 30332, USA.
- Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, 315 Ferst Drive, Atlanta, GA, 30332, USA.
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Review of the Applications of Biomedical Compositions Containing Hydroxyapatite and Collagen Modified by Bioactive Components. MATERIALS 2021; 14:ma14092096. [PMID: 33919199 PMCID: PMC8122483 DOI: 10.3390/ma14092096] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/11/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023]
Abstract
Regenerative medicine is becoming a rapidly evolving technique in today’s biomedical progress scenario. Scientists around the world suggest the use of naturally synthesized biomaterials to repair and heal damaged cells. Hydroxyapatite (HAp) has the potential to replace drugs in biomedical engineering and regenerative drugs. HAp is easily biodegradable, biocompatible, and correlated with macromolecules, which facilitates their incorporation into inorganic materials. This review article provides extensive knowledge on HAp and collagen-containing compositions modified with drugs, bioactive components, metals, and selected nanoparticles. Such compositions consisting of HAp and collagen modified with various additives are used in a variety of biomedical applications such as bone tissue engineering, vascular transplantation, cartilage, and other implantable biomedical devices.
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8
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Dorogin J, Townsend JM, Hettiaratchi MH. Biomaterials for protein delivery for complex tissue healing responses. Biomater Sci 2021; 9:2339-2361. [PMID: 33432960 DOI: 10.1039/d0bm01804j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tissue repair requires a complex cascade of events mediated by a variety of cells, proteins, and matrix molecules; however, the healing cascade can be easily disrupted by numerous factors, resulting in impaired tissue regeneration. Recent advances in biomaterials for tissue regeneration have increased the ability to tailor the delivery of proteins and other biomolecules to injury sites to restore normal healing cascades and stimulate robust tissue repair. In this review, we discuss the evolution of the field toward creating biomaterials that precisely control protein delivery to stimulate tissue regeneration, with a focus on addressing complex and dynamic injury environments. We highlight biomaterials that leverage different mechanisms to deliver and present proteins involved in healing cascades, tissue targeting and mimicking strategies, materials that can be triggered by environmental cues, and integrated strategies that combine multiple biomaterial properties to improve protein delivery. Improvements in biomaterial design to address complex injury environments will expand our understanding of both normal and aberrant tissue repair processes and ultimately provide a better standard of patient care.
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Affiliation(s)
- Jonathan Dorogin
- Knight Campus for Accelerating Scientific Impact, University of Oregon, 6321 University of Oregon, Eugene, OR 97401, USA.
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Oliveira ÉR, Nie L, Podstawczyk D, Allahbakhsh A, Ratnayake J, Brasil DL, Shavandi A. Advances in Growth Factor Delivery for Bone Tissue Engineering. Int J Mol Sci 2021; 22:E903. [PMID: 33477502 PMCID: PMC7831065 DOI: 10.3390/ijms22020903] [Citation(s) in RCA: 84] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 12/17/2022] Open
Abstract
Shortcomings related to the treatment of bone diseases and consequent tissue regeneration such as transplants have been addressed to some extent by tissue engineering and regenerative medicine. Tissue engineering has promoted structures that can simulate the extracellular matrix and are capable of guiding natural bone repair using signaling molecules to promote osteoinduction and angiogenesis essential in the formation of new bone tissues. Although recent studies on developing novel growth factor delivery systems for bone repair have attracted great attention, taking into account the complexity of the extracellular matrix, scaffolding and growth factors should not be explored independently. Consequently, systems that combine both concepts have great potential to promote the effectiveness of bone regeneration methods. In this review, recent developments in bone regeneration that simultaneously consider scaffolding and growth factors are covered in detail. The main emphasis in this overview is on delivery strategies that employ polymer-based scaffolds for spatiotemporal-controlled delivery of both single and multiple growth factors in bone-regeneration approaches. From clinical applications to creating alternative structural materials, bone tissue engineering has been advancing constantly, and it is relevant to regularly update related topics.
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Affiliation(s)
- Érica Resende Oliveira
- Food Engineering Department, School of Agronomy, Universidade Federal de Goiás, Campus Samambaia, Goiânia CEP 74690-900, Goiás, Brazil;
| | - Lei Nie
- College of Life Sciences, Xinyang Normal University, Xinyang 464000, China
| | - Daria Podstawczyk
- Department of Process Engineering and Technology of Polymer and Carbon Materials, Faculty of Chemistry, Wroclaw University of Science and Technology, 4/6 Norwida Street, 50-373 Wroclaw, Poland;
| | - Ahmad Allahbakhsh
- Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487, Iran;
| | - Jithendra Ratnayake
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand;
| | - Dandara Lima Brasil
- Food Science Department, Universidade Federal de Lavras, Lavras CEP 37200-900, Minas Gerais, Brazil;
| | - Amin Shavandi
- BioMatter Unit—École Polytechnique de Bruxelles, Université Libre de Bruxelles, Avenue F.D. Roosevelt, 50—CP 165/61, 1050 Brussels, Belgium
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Bizeau J, Mertz D. Design and applications of protein delivery systems in nanomedicine and tissue engineering. Adv Colloid Interface Sci 2021; 287:102334. [PMID: 33341459 DOI: 10.1016/j.cis.2020.102334] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/24/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023]
Abstract
Proteins are biological macromolecules involved in a wide range of biological functions, which makes them very appealing as therapeutics agents. Indeed, compared to small molecule drugs, their endogenous nature ensures their biocompatibility and biodegradability, they can be used in a large range of applications and present a higher specificity and activity. However, they suffer from unfolding, enzymatic degradation, short half-life and poor membrane permeability. To overcome such drawbacks, the development of protein delivery systems to protect, carry and deliver them in a controlled way have emerged importantly these last years. In this review, the formulation of a wide panel of protein delivery systems either in the form of polymer or inorganic nanoengineered colloids and scaffolds are presented and the protein loading and release mechanisms are addressed. A section is also dedicated to the detection of proteins and the characterization methods of their release. Then, the main protein delivery systems developed these last three years for anticancer, tissue engineering or diabetes applications are presented, as well as the major in vivo models used to test them. The last part of this review aims at presenting the perspectives of the field such as the use of protein-rich material or the sequestration of proteins. This part will also deal with less common applications and gene therapy as an indirect method to deliver protein.
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11
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Guan N, Liu Z, Zhao Y, Li Q, Wang Y. Engineered biomaterial strategies for controlling growth factors in tissue engineering. Drug Deliv 2020; 27:1438-1451. [PMID: 33100031 PMCID: PMC7594870 DOI: 10.1080/10717544.2020.1831104] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/19/2020] [Accepted: 09/28/2020] [Indexed: 12/16/2022] Open
Abstract
Growth factors are multi-functional signaling molecules that coordinate multi-stage process of wound healing. During wound healing, growth factors are transmitted to wound environment in a positive and physiologically related way, therefore, there is a broad prospect for studying the mediated healing process through growth factors. However, growth factors (GFs) themselves have disadvantages of instability, short life, rapid inactivation of physiological conditions, low safety and easy degradation, which hinder the clinical use of GFs. Rapid development of delivery strategies for GFs has been trying to solve the instability and insecurity of GFs. Particularly, in recent years, GFs delivered by scaffolds based on biomaterials have become a hotspot in this filed. This review introduces various delivery strategies for growth factors based on new biodegradable materials, especially polysaccharides, which could provide guidance for the development of the delivery strategies for growth factors in clinic.
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Affiliation(s)
- Na Guan
- College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Qingdao, P. R. China
| | - Zhihai Liu
- College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Qingdao, P. R. China
| | - Yonghui Zhao
- Qingdao Central Hospital, The Second Affiliated Hospital of Qingdao University, Qingdao, P. R. China
| | - Qiu Li
- College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Qingdao, P. R. China
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau SAR, China
| | - Yitao Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau SAR, China
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Bone Morphogenetic Protein 2 (BMP-2) Aggregates Can be Solubilized by Albumin-Investigation of BMP-2 Aggregation by Light Scattering and Electrophoresis. Pharmaceutics 2020; 12:pharmaceutics12121143. [PMID: 33255722 PMCID: PMC7760923 DOI: 10.3390/pharmaceutics12121143] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/15/2020] [Accepted: 11/20/2020] [Indexed: 12/18/2022] Open
Abstract
Bone morphogenetic protein 2 (BMP-2) has a high tendency to aggregate at physiological pH and physiological ionic strength, which can complicate the development of growth factor delivery systems. The aggregation behavior in differently concentrated BMP-2 solutions was investigated using dynamic and static light scattering. It was found that at higher concentrations larger aggregates are formed, whose size decreases again with increasing dilution. A solubilizing effect and therefore less aggregation was observed upon the addition of albumin. Imaged capillary isoelectric focusing and the simulation of the surface charges of BMP-2 were used to find a possible explanation for the unusually low solubility of BMP-2 at physiological pH. In addition to hydrophobic interactions, attractive electrostatic interactions might be decisive in the aggregation of BMP-2 due to the particular distribution of surface charges. These results help to better understand the solubility behavior of BMP-2 and thus support future pharmaceutical research and the development of new strategies for the augmentation of bone healing.
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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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14
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Sundermann J, Oehmichen S, Sydow S, Burmeister L, Quaas B, Hänsch R, Rinas U, Hoffmann A, Menzel H, Bunjes H. Varying the sustained release of BMP-2 from chitosan nanogel-functionalized polycaprolactone fiber mats by different polycaprolactone surface modifications. J Biomed Mater Res A 2020; 109:600-614. [PMID: 32608183 DOI: 10.1002/jbm.a.37045] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 06/23/2020] [Indexed: 12/16/2022]
Abstract
Polycaprolactone (PCL) fiber mats with different surface modifications were functionalized with a chitosan nanogel coating to attach the growth factor human bone morphogenetic protein 2 (BMP-2). Three different hydrophilic surface modifications were compared with regard to the binding and in vitro release of BMP-2. The type of surface modification and the specific surface area derived from the fiber thickness had an important influence on the degree of protein loading. Coating the PCL fibers with polydopamine resulted in the binding of the largest BMP-2 quantity per surface area. However, most of the binding was irreversible over the investigated period of time, causing a low release in vitro. PCL fiber mats with a chitosan-graft-PCL coating and an additional alginate layer, as well as PCL fiber mats with an air plasma surface modification boundless BMP-2, but the immobilized protein could almost completely be released. With polydopamine and plasma modifications as well as with unmodified PCL, high amounts of BMP-2 could also be attached directly to the surface. Integration of BMP-2 into the chitosan nanogel functionalization considerably increased binding on all hydrophilized surfaces and resulted in a sustained release with an initial burst release of BMP-2 without detectable loss of bioactivity in vitro.
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Affiliation(s)
- Julius Sundermann
- Technische Universität Braunschweig, Institut für Pharmazeutische Technologie und Biopharmazie, Braunschweig, Germany
| | - Sarah Oehmichen
- Technische Universität Braunschweig, Institut für Technische Chemie, Braunschweig, Germany
| | - Steffen Sydow
- Technische Universität Braunschweig, Institut für Technische Chemie, Braunschweig, Germany
| | - Laura Burmeister
- Niedersächsisches Zentrum für Biomedizintechnik, Implantatforschung und Entwicklung (NIFE), Hannover, Germany.,Medizinische Hochschule Hannover (MHH), Labor für Biomechanik und Biomaterialien, Orthopädische Klinik, Gradierte Implantate und Regenerative Strategien im Skelettsystem, Hannover, Germany
| | - Bastian Quaas
- Leibniz Universität Hannover, Institut für Technische Chemie, Hannover, Germany
| | - Robert Hänsch
- Technische Universität Braunschweig, Institut für Pflanzenbiologie, Braunschweig, Germany.,Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing, China
| | - Ursula Rinas
- Leibniz Universität Hannover, Institut für Technische Chemie, Hannover, Germany.,Helmholtz-Zentrum für Infektionsforschung, Braunschweig, Germany
| | - Andrea Hoffmann
- Niedersächsisches Zentrum für Biomedizintechnik, Implantatforschung und Entwicklung (NIFE), Hannover, Germany.,Medizinische Hochschule Hannover (MHH), Labor für Biomechanik und Biomaterialien, Orthopädische Klinik, Gradierte Implantate und Regenerative Strategien im Skelettsystem, Hannover, Germany
| | - Henning Menzel
- Technische Universität Braunschweig, Institut für Technische Chemie, Braunschweig, Germany
| | - Heike Bunjes
- Technische Universität Braunschweig, Institut für Pharmazeutische Technologie und Biopharmazie, Braunschweig, Germany
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15
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Enriquez-Ochoa D, Robles-Ovalle P, Mayolo-Deloisa K, Brunck MEG. Immobilization of Growth Factors for Cell Therapy Manufacturing. Front Bioeng Biotechnol 2020; 8:620. [PMID: 32637403 PMCID: PMC7317031 DOI: 10.3389/fbioe.2020.00620] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/20/2020] [Indexed: 12/21/2022] Open
Abstract
Cell therapy products exhibit great therapeutic potential but come with a deterring price tag partly caused by their costly manufacturing processes. The development of strategies that lead to cost-effective cell production is key to expand the reach of cell therapies. Growth factors are critical culture media components required for the maintenance and differentiation of cells in culture and are widely employed in cell therapy manufacturing. However, they are expensive, and their common use in soluble form is often associated with decreased stability and bioactivity. Immobilization has emerged as a possible strategy to optimize growth factor use in cell culture. To date, several immobilization techniques have been reported for attaching growth factors onto a variety of biomaterials, but these have been focused on tissue engineering. This review briefly summarizes the current landscape of cell therapy manufacturing, before describing the types of chemistry that can be used to immobilize growth factors for cell culture. Emphasis is placed to identify strategies that could reduce growth factor usage and enhance bioactivity. Finally, we describe a case study for stem cell factor.
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Affiliation(s)
| | | | - Karla Mayolo-Deloisa
- Tecnologico de Monterrey, School of Engineering and Science, FEMSA Biotechnology Center, Monterrey, Mexico
| | - Marion E. G. Brunck
- Tecnologico de Monterrey, School of Engineering and Science, FEMSA Biotechnology Center, Monterrey, Mexico
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16
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Hettiaratchi MH, Krishnan L, Rouse T, Chou C, McDevitt TC, Guldberg RE. Heparin-mediated delivery of bone morphogenetic protein-2 improves spatial localization of bone regeneration. SCIENCE ADVANCES 2020; 6:eaay1240. [PMID: 31922007 PMCID: PMC6941907 DOI: 10.1126/sciadv.aay1240] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 11/07/2019] [Indexed: 05/25/2023]
Abstract
Supraphysiologic doses of bone morphogenetic protein-2 (BMP-2) are used clinically to promote bone formation in fracture nonunions, large bone defects, and spinal fusion. However, abnormal bone formation (i.e., heterotopic ossification) caused by rapid BMP-2 release from conventional collagen sponge scaffolds is a serious complication. We leveraged the strong affinity interactions between heparin microparticles (HMPs) and BMP-2 to improve protein delivery to bone defects. We first developed a computational model to investigate BMP-2-HMP interactions and demonstrated improved in vivo BMP-2 retention using HMPs. We then evaluated BMP-2-loaded HMPs as a treatment strategy for healing critically sized femoral defects in a rat model that displays heterotopic ossification with clinical BMP-2 doses (0.12 mg/kg body weight). HMPs increased BMP-2 retention in vivo, improving spatial localization of bone formation in large bone defects and reducing heterotopic ossification. Thus, HMPs provide a promising opportunity to improve the safety profile of scaffold-based BMP-2 delivery.
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Affiliation(s)
- Marian H. Hettiaratchi
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30322, USA
- The Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR 97403, USA
| | - Laxminarayanan Krishnan
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30322, USA
| | - Tel Rouse
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30322, USA
| | - Catherine Chou
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30322, USA
| | - Todd C. McDevitt
- The Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA 94158, USA
| | - Robert E. Guldberg
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30322, USA
- The Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR 97403, USA
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17
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Qasim M, Chae DS, Lee NY. Bioengineering strategies for bone and cartilage tissue regeneration using growth factors and stem cells. J Biomed Mater Res A 2019; 108:394-411. [PMID: 31618509 DOI: 10.1002/jbm.a.36817] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 10/03/2019] [Accepted: 10/10/2019] [Indexed: 12/14/2022]
Abstract
Bone and cartilage tissue engineering is an integrative approach that is inspired by the phenomena associated with wound healing. In this respect, growth factors have emerged as important moieties for the control and regulation of this process. Growth factors act as mediators and control the important physiological functions of bone regeneration. Herein, we discuss the importance of growth factors in bone and cartilage tissue engineering, their loading and delivery strategies, release kinetics, and their integration with biomaterials and stem cells to heal bone fractures. We also highlighted the role of growth factors in the determination of the bone tissue microenvironment based on the reciprocal signaling with cells and biomaterial scaffolds on which future bone and cartilage tissue engineering technologies and medical devices will be based upon.
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Affiliation(s)
- Muhammad Qasim
- Department of BioNano Technology, Gachon University, Seongnam-si, Republic of Korea
| | - Dong Sik Chae
- Department of Orthopedic Surgery, International St. Mary's Hospital, Catholic Kwandong University College of Medicine, Incheon, Republic of Korea
| | - Nae Yoon Lee
- Department of BioNano Technology, Gachon University, Seongnam-si, Republic of Korea
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18
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Abstract
Stem cell therapy is a promising alternative approach to the treatment of a number of incurable degenerative diseases. However, low cell retention and survival after transplantation limit the therapeutic efficacy of stem cells for clinical translational applications. The utilization of biomaterials has been progressively successful in controlling the fate of transplanted cells by imitating the cellular microenvironment for optimal tissue repair and regeneration. This review mainly focuses on the engineered microenvironments with synthetic biomaterials in modification of stem cell behaviors. Moreover, the possible advancements in translational therapy by using biomaterials with stem cells are prospected and the challenges of the current restriction in clinical applications are highlighted.
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19
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Hettiaratchi MH, Shoichet MS. Modulated Protein Delivery to Engineer Tissue Repair. Tissue Eng Part A 2019; 25:925-930. [PMID: 30848169 DOI: 10.1089/ten.tea.2019.0066] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
IMPACT STATEMENT Achieving targeted protein delivery to injured tissues is a core focus of the field of tissue engineering and has enormous clinical potential. This article highlights significant advances made in biomaterial-based protein delivery strategies over the last 25 years and how they will influence research in the next 25 years. These advances will enable protein release rates to be tuned with increased flexibility to deliberately address the challenges of the dynamic injury environment and ultimately lead to better solutions for patients.
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Affiliation(s)
- Marian H Hettiaratchi
- 1Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Canada.,2Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Molly S Shoichet
- 1Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Canada.,2Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada.,3Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada.,4Department of Chemistry, University of Toronto, Toronto, Canada
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20
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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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21
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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: 111] [Impact Index Per Article: 22.2] [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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22
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He C, Ji H, Qian Y, Wang Q, Liu X, Zhao W, Zhao C. Heparin-based and heparin-inspired hydrogels: size-effect, gelation and biomedical applications. J Mater Chem B 2019; 7:1186-1208. [DOI: 10.1039/c8tb02671h] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The size-effect, fabrication methods and biomedical applications of heparin-based and heparin-inspired hydrogels are reviewed.
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Affiliation(s)
- Chao He
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Haifeng Ji
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Yihui Qian
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Qian Wang
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Xiaoling Liu
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Weifeng Zhao
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Changsheng Zhao
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
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23
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Cai B, Zou Q, Zuo Y, Mei Q, Ma J, Lin L, Chen L, Li Y. Injectable Gel Constructs with Regenerative and Anti-Infective Dual Effects Based on Assembled Chitosan Microspheres. ACS APPLIED MATERIALS & INTERFACES 2018; 10:25099-25112. [PMID: 29952200 DOI: 10.1021/acsami.8b06648] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
There is increasing demand for biomaterials that both assist with bone regeneration and have anti-infection qualities in clinical applications. To achieve this goal, chitosan microspheres with either positive or negative charges were fabricated and then assembled as a gel for bone healing. The positively charged chitosan microspheres (CSM; ∼35.5 μm) and negatively charged O-carboxymethyl chitosan microspheres (CMCSM; ∼13.5 μm) were loaded, respectively, with bone morphogenetic protein (BMP-2) and berberine (Bbr) via swollen encapsulation and physical adsorption without a significant change in the electric charges. The release kinetics of BMP-2 and Bbr from the microspheres were also studied in vitro. The results showed that the Bbr/CMCSM microsphere group possessed high antibacterial activity against Staphylococcus aureus; the BMP-2/CSM microsphere group also had excellent cytocompatibility and improved osteoinductivity with the assistance of BMP-2. The assembled gel group consisting of Bbr/CMCSM and BMP-2/CSM had a porous structure that allowed biological signal transfer and tissue infiltration and exhibited significantly enhanced bone reconstruction compared with that of the respective microsphere groups, which should result from the osteoconductivity of the porous structure and the osteoinduction of the BMP-2 growth factor. The oppositely charged microspheres and their assembled gel provide a promising prospect for making injectable tissue-engineered constructs with regenerative and anti-infective dual effects for biomedical applications.
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Affiliation(s)
- Bin Cai
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
| | - Qin Zou
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
| | - Yi Zuo
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
| | - Quanjing Mei
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
| | - Jinqi Ma
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
| | - Lili Lin
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
| | - Li Chen
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
| | - Yubao Li
- Research Center for Nano-Biomaterial, Analytical & Testing Center , Sichuan University , Chengdu 610064 , China
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24
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Akhtar F, Wan X, Wu G, Kesse S, Wang S, He S. Low-Molecular-Weight Heparins: Reduced Size Particulate Systems for Improved Therapeutic Outcomes. Molecules 2018; 23:E1757. [PMID: 30021958 PMCID: PMC6100363 DOI: 10.3390/molecules23071757] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 06/21/2018] [Accepted: 07/04/2018] [Indexed: 01/10/2023] Open
Abstract
A wide range of diseases have been treated using low-molecular-weight heparins (LMWHs), the drug of choice for anticoagulation. Owing to their better pharmacokinetic features compared to those of unfractionated heparin (uFH), several systems incorporating LMWHs have been investigated to deliver and improve their therapeutic outcomes, especially through development of their micro- and nano-particles. This review article describes current perspectives on the fabrication, characterization, and application of LMWHs-loaded micro- and nano-particles to achieve ameliorated bioavailability. The valuable applications of LMWH will continue to encourage researchers to identify efficient delivery systems that have specific release characteristics and ameliorated bioavailability, overcoming the challenges presented by biological obstructions and the physicochemical properties of LMWHs.
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Affiliation(s)
- Fahad Akhtar
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China.
| | - Xinyu Wan
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China.
| | - Gang Wu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China.
| | - Samuel Kesse
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, School of Pharmacy, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
| | - Shaoda Wang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China.
| | - Shuying He
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China.
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25
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Cheng A, Krishnan L, Tran L, Stevens HY, Xia B, Lee N, Williams JK, Gibson G, Guldberg RE. The Effects of Age and Dose on Gene Expression and Segmental Bone Defect Repair After BMP-2 Delivery. JBMR Plus 2018; 3:e10068. [PMID: 30828685 PMCID: PMC6383700 DOI: 10.1002/jbm4.10068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/31/2018] [Accepted: 06/12/2018] [Indexed: 11/25/2022] Open
Abstract
Age is a well‐known influential factor in bone healing, with younger patients generally healing bone fractures more rapidly and suffering fewer complications compared with older patients. Yet the impact age has on the response to current bone healing treatments, such as delivery of bone morphogenetic protein 2 (BMP‐2), remains poorly characterized. It remains unclear how or if therapeutic dosing of BMP‐2 should be modified to account for age‐related differences in order to minimize potential adverse effects and consequently improve patient bone‐healing outcomes. For this study, we sought to address this issue by using a preclinical critically sized segmental bone defect model in rats to investigate age‐related differences in bone repair after delivery of BMP‐2 in a collagen sponge, the current clinical standard. Femoral defects were created in young (7‐week‐old) and adult (8‐month‐old) rats, and healing was assessed using gene expression analyses, longitudinal radiography, ex vivo micro‐computed tomography (µCT), as well as torsional testing. We found that young rats demonstrated elevated expression of genes related to osteogenesis, chondrogenesis, and matrix remodeling at the early 1‐week time point compared with adult rats. These early gene expression differences may have impacted long‐term healing as the regenerated bones of young rats exhibited higher bone mineral densities compared with those of adult rats after 12 weeks. Furthermore, the young rats demonstrated significantly more bone formation and increased mechanical strength when BMP‐2 dose was increased from 1 µg to 10 µg, a finding not observed in adult rats. Overall, these results indicate there are age‐related differences in BMP‐2‐mediated bone regeneration, including relative dose sensitivity, suggesting that age is an important consideration when implementing a BMP‐2 treatment strategy. © 2018 The Authors JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Albert Cheng
- George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology Atlanta GA USA.,Parker H. Petit Institute for Bioengineering and Bioscience Georgia Institute of Technology Atlanta GA USA
| | - Laxminarayanan Krishnan
- Parker H. Petit Institute for Bioengineering and Bioscience Georgia Institute of Technology Atlanta GA USA
| | - Lisa Tran
- Emory University School of Medicine Atlanta GA USA
| | - Hazel Y Stevens
- George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology Atlanta GA USA
| | - Boao Xia
- George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology Atlanta GA USA
| | - Nari Lee
- Emory University Pediatric Engineering Research Summer Experience Atlanta GA USA
| | | | - Greg Gibson
- Center for Integrative Genomics School of Biological Sciences Georgia Institute of Technology Atlanta GA USA
| | - Robert E Guldberg
- George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology Atlanta GA USA.,Parker H. Petit Institute for Bioengineering and Bioscience Georgia Institute of Technology Atlanta GA USA
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Rinker TE, Philbrick BD, Hettiaratchi MH, Smalley DM, McDevitt TC, Temenoff JS. Microparticle-mediated sequestration of cell-secreted proteins to modulate chondrocytic differentiation. Acta Biomater 2018; 68:125-136. [PMID: 29292168 DOI: 10.1016/j.actbio.2017.12.038] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/05/2017] [Accepted: 12/22/2017] [Indexed: 10/18/2022]
Abstract
Protein delivery is often used in tissue engineering applications to control differentiation processes, but is limited by protein instability and cost. An alternative approach is to control the cellular microenvironment through biomaterial-mediated sequestration of cell-secreted proteins important to differentiation. Thus, we utilized heparin-based microparticles to modulate cellular differentiation via protein sequestration in an in vitro model system of endochondral ossification. Heparin and poly(ethylene-glycol) (PEG; a low-binding material control)-based microparticles were incorporated into ATDC5 cell spheroids or incubated with ATDC5 cells in transwell culture. Reduced differentiation was observed in the heparin microparticle group as compared to PEG and no microparticle-containing groups. To determine if observed changes were due to sequestration of cell-secreted protein, the proteins sequestered by heparin microparticles were analyzed using SDS-PAGE and mass spectrometry. It was found that heparin microparticles bound insulin-like growth factor binding proteins (IGFBP)-3 and 5. When incubated with a small-molecule inhibitor of IGFBPs, NBI 31772, a similar delay in differentiation of ATDC5 cells was observed. These results indicate that heparin microparticles modulated chondrocytic differentiation in this system via sequestration of cell-secreted protein, a technique that could be beneficial in the future as a means to control cellular differentiation processes. STATEMENT OF SIGNIFICANCE In this work, we present a proof-of-principle set of experiments in which heparin-based microparticles are shown to modulate cellular differentiation through binding of cell-secreted protein. Unlike existing systems that rely on expensive protein with limited half-lives to elicit changes in cellular behavior, this technique focuses on temporal modulation of cell-generated proteins. This technique also provides a biomaterials-based method that can be used to further identify sequestered proteins of interest. Thus, this work indicates that glycosaminoglycan-based biomaterial approaches could be used as substitutes or additions to traditional methods for modulating and identifying the cell-secreted proteins involved in directing cellular behavior.
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Bruggeman KF, Williams RJ, Nisbet DR. Dynamic and Responsive Growth Factor Delivery from Electrospun and Hydrogel Tissue Engineering Materials. Adv Healthc Mater 2018; 7. [PMID: 29193871 DOI: 10.1002/adhm.201700836] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 09/04/2017] [Indexed: 12/21/2022]
Abstract
Tissue engineering scaffolds are designed to mimic physical, chemical, and biological features of the extracellular matrix, thereby providing a constant support that is crucial to improved regenerative medicine outcomes. Beyond mechanical and structural support, the next generation of these materials must also consider the more dynamic presentation and delivery of drugs or growth factors to guide new and regenerating tissue development. These two aspects are explored expansively separately, but they must interact synergistically to achieve optimal regeneration. This review explores common tissue engineering materials types, electrospun polymers and hydrogels, and strategies used for incorporating drug delivery systems into these scaffolds.
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Affiliation(s)
- Kiara F. Bruggeman
- Laboratory of Advanced Biomaterials; Research School of Engineering; The Australian National University; Canberra ACT 2601 Australia
| | - Richard J. Williams
- School of Engineering; RMIT University; Melbourne VIC 3001 Australia
- Biofab3D; Aikenhead Center for Medical Discovery; St. Vincent's Hospital; Melbourne VIC 3065 Australia
| | - David R. Nisbet
- Laboratory of Advanced Biomaterials; Research School of Engineering; The Australian National University; Canberra ACT 2601 Australia
- Biofab3D; Aikenhead Center for Medical Discovery; St. Vincent's Hospital; Melbourne VIC 3065 Australia
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28
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Hettiaratchi MH, Rouse T, Chou C, Krishnan L, Stevens HY, Li MTA, McDevitt TC, Guldberg RE. Enhanced in vivo retention of low dose BMP-2 via heparin microparticle delivery does not accelerate bone healing in a critically sized femoral defect. Acta Biomater 2017; 59:21-32. [PMID: 28645809 PMCID: PMC6546418 DOI: 10.1016/j.actbio.2017.06.028] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 05/09/2017] [Accepted: 06/19/2017] [Indexed: 11/20/2022]
Abstract
Bone morphogenetic protein-2 (BMP-2) is an osteoinductive growth factor used clinically to induce bone regeneration and fusion. Some complications associated with BMP-2 treatment have been attributed to rapid release of BMP-2 from conventional collagen scaffolds, motivating the development of tunable sustained-release strategies. We incorporated BMP-2-binding heparin microparticles (HMPs) into a hydrogel scaffold to improve spatiotemporal control of BMP-2 delivery to large bone defects. HMPs pre-loaded with BMP-2 were mixed into alginate hydrogels and compared to hydrogels containing BMP-2 alone. BMP-2 release from scaffolds in vitro, BMP-2 retention within injury sites in vivo, and bone regeneration in a critically sized femoral defect were evaluated. Compared to hydrogel delivery alone, BMP-2-loaded HMPs reduced BMP-2 release in vitro and increased early BMP-2 retention in the bone defect. BMP-2-loaded HMPs induced bone formation at both ectopic and orthotopic sites; however, the volume of induced bone was lower for defects treated with BMP-2-loaded HMPs compared to hydrogel delivery. To better understand the effect of HMPs on BMP-2 release kinetics, a computational model was developed to predict BMP-2 release from constructs in vivo. The model suggested that HMPs limited BMP-2 release into surrounding tissues, and that changing the HMP density could modulate BMP-2 release. Taken together, these experimental and computational results suggest the importance of achieving a balance of BMP-2 retention within the bone defect and BMP-2 release into surrounding soft tissues. HMP delivery of BMP-2 may provide a method of tuning BMP-2 release in vivo that can be further investigated to improve current methods of bone regeneration. STATEMENT OF SIGNIFICANCE The development of effective biomaterials for sustained protein delivery is a crucial component of tissue engineering strategies. However, in most applications, including bone repair, the optimal balance between protein presentation in the injury site and protein release into the surrounding tissues is unknown. Herein, we introduced heparin microparticles (HMPs) into a tissue engineered construct to increase in vivo retention of bone morphogenetic protein-2 (BMP-2) and enhance healing in femoral defects. Although HMPs induced bone regeneration, no increase in bone volume was observed, leading to further experimental and computational analysis of the effect of HMP-BMP-2 interactions on protein retention and release. Ultimately, this work provides insight into designing tunable protein-material interactions and their implications for controlling BMP-2 delivery.
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Affiliation(s)
- Marian H Hettiaratchi
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, United States
| | - Tel Rouse
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, United States; The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
| | - Catherine Chou
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, United States
| | - Laxminarayanan Krishnan
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
| | - Hazel Y Stevens
- The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Mon-Tzu A Li
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, United States
| | - Todd C McDevitt
- The Gladstone Institute of Cardiovascular Disease, San Francisco, CA, United States; The Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, United States
| | - Robert E Guldberg
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States; The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United States.
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