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Nejati S, Mongeau L. In Vitro Investigation of Vocal Fold Cellular Response to Variations in Hydrogel Porosity and Elasticity. ACS Biomater Sci Eng 2024; 10:3909-3922. [PMID: 38783819 DOI: 10.1021/acsbiomaterials.4c00197] [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] [Indexed: 05/25/2024]
Abstract
Tissue regeneration is intricately influenced by the dynamic interplay between the physical attributes of tissue engineering scaffolds and the resulting biological responses. A tunable microporous hydrogel system was engineered using gelatin methacryloyl (GelMA) and polyethylene glycol diacrylate (PEGDA), with polyethylene glycol (PEG) serving as a porogen. Through systematic variation of PEGDA molecular weights, hydrogels with varying mechanical and architectural properties were obtained. The objective of the present study was to elucidate the impact of substrate mechanics and architecture on the immunological and reparative activities of vocal fold tissues. Mechanical characterization of the hydrogels was performed using tensile strength measurements and rheometry. Their morphological properties were investigated using scanning electron microscopy (SEM) and confocal microscopy. A series of biological assays were conducted. Cellular morphology, differentiation, and collagen synthesis of human vocal fold fibroblasts (hVFFs) were evaluated using immunostaining. Fibroblast proliferation was studied using the WST-1 assay, and cell migration was investigated via the Boyden chamber assay. Macrophage polarization and secretions were also examined using immunostaining and ELISA. The results revealed that increasing the molecular weight of PEGDA from 700 Da to 10,000 Da resulted in decreased hydrogel stiffness, from 62.6 to 8.8 kPa, and increased pore dimensions from approximately 64.9 to 137.4 μm. Biological evaluations revealed that hydrogels with a higher stiffness promoted fibroblast proliferation and spreading, albeit with an increased propensity for fibrosis, as indicated by a surge in myofibroblast differentiation and collagen synthesis. In contrast, hydrogels with greater molecular weights had a softer matrix with expanded pores, enhancing cellular migration and promoting an M2 macrophage phenotype conducive to tissue healing. The findings show that the hydrogels formulated with a PEGDA molecular weight of 6000 Da are best among the hydrogels considered for vocal fold repair. The microporous hydrogels could be tuned to serve in other tissue engineering applications.
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Affiliation(s)
- Sara Nejati
- Department of Mechanical Engineering, McGill University, Montreal H3A 0C3, Canada
| | - Luc Mongeau
- Department of Mechanical Engineering, McGill University, Montreal H3A 0C3, Canada
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2
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Kozan NG, Caswell S, Patel M, Grasman JM. Aligned Collagen Sponges with Tunable Pore Size for Skeletal Muscle Tissue Regeneration. J Funct Biomater 2023; 14:533. [PMID: 37998102 PMCID: PMC10672557 DOI: 10.3390/jfb14110533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/20/2023] [Accepted: 10/22/2023] [Indexed: 11/25/2023] Open
Abstract
Volumetric muscle loss (VML) is a traumatic injury where at least 20% of the mass of a skeletal muscle has been destroyed and functionality is lost. The standard treatment for VML, autologous tissue transfer, is limited as approximately 1 in 10 grafts fail because of necrosis or infection. Tissue engineering strategies seek to develop scaffolds that can regenerate injured muscles and restore functionality. Many of these scaffolds, however, are limited in their ability to restore muscle functionality because of an inability to promote the alignment of regenerating myofibers. For aligned myofibers to form on a scaffold, myoblasts infiltrate the scaffold and receive topographical cues to direct targeted myofiber growth. We seek to determine the optimal pore size for myoblast infiltration and differentiation. We developed a method of tuning the pore size within collagen scaffolds while inducing longitudinal alignment of these pores. Significantly different pore sizes were generated by adjusting the freezing rate of the scaffolds. Scaffolds frozen at -20 °C contained the largest pores. These scaffolds promoted the greatest level of cell infiltration and orientation in the direction of pore alignment. Further research will be conducted to induce higher levels of myofiber formation, to ultimately create an off-the-shelf treatment for VML injuries.
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Affiliation(s)
| | | | | | - Jonathan M. Grasman
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
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3
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Xu G, Xiao L, Guo P, Wang Y, Ke S, Lyu G, Ding X, Lu Q, Kaplan DL. Silk Nanofiber Scaffolds with Multiple Angiogenic Cues to Accelerate Wound Regeneration. ACS Biomater Sci Eng 2023; 9:5813-5823. [PMID: 37710361 DOI: 10.1021/acsbiomaterials.3c01023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Niches with multiple physical and chemical cues can influence the fate of cells and tissues in vivo. Simulating the in vivo niche in the design of bioactive materials is a challenge, particularly to tune multiple cues simultaneously in the same system. Here, an assembly strategy was developed to regulate multiple cues in the same scaffold based on the use of two silk nanofiber components that respond differently during the fabrication processes. An aqueous solution containing the two components, amorphous silk nanofibers (ASNFs) and β-sheet-rich silk nanofibers (BSNFs), was sequentially treated with an electrical field and freeze-drying processes where the BSNFs oriented to the electrical field, while the ASNFs formed stable porous structures during the lyophilization process to impact the mechanical properties. Bioactive cargo, such as deferoxamine (DFO), was loaded on the BSNFs to enrich cell responses with the scaffolds. The in vitro results revealed that the loaded DFO and the anisotropic structures with improved mechanical properties resulted in better vascularization than those of the scaffolds without the anisotropic features. The multiple cues in the scaffolds provided angiogenic niches to accelerate wound healing.
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Affiliation(s)
- Gang Xu
- Department of Orthopedics, The Affiliated Lianyungang Hospital of Xuzhou Medical University, Lianyungang 222061, People's Republic of China
- State Key Laboratory of Radiation Medicine and Radiation Protection, Institutes for Translational Medicine, Soochow University, Suzhou 215123, People's Republic of China
- Department of Orthopedics, The First Affiliated Hospital of Kanda College of Nanjing Medical University, Lianyungang 222061, People's Republic of China
| | - Liying Xiao
- State Key Laboratory of Radiation Medicine and Radiation Protection, Institutes for Translational Medicine, Soochow University, Suzhou 215123, People's Republic of China
| | - Peng Guo
- Engineering Research Center of the Ministry of Education for Wound Repair Technology, Jiangnan University, The Affiliated Hospital of Jiangnan University, Wuxi 214041, People's Republic of China
| | - Yuanyuan Wang
- State Key Laboratory of Radiation Medicine and Radiation Protection, Institutes for Translational Medicine, Soochow University, Suzhou 215123, People's Republic of China
| | - Shiyu Ke
- State Key Laboratory of Radiation Medicine and Radiation Protection, Institutes for Translational Medicine, Soochow University, Suzhou 215123, People's Republic of China
| | - Guozhong Lyu
- Engineering Research Center of the Ministry of Education for Wound Repair Technology, Jiangnan University, The Affiliated Hospital of Jiangnan University, Wuxi 214041, People's Republic of China
| | - Xiangsheng Ding
- Department of Burns, The Affiliated Lianyungang Hospital of Xuzhou Medical University, Lianyungang 222061, People's Republic of China
| | - Qiang Lu
- State Key Laboratory of Radiation Medicine and Radiation Protection, Institutes for Translational Medicine, Soochow University, Suzhou 215123, People's Republic of China
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
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4
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Castillo V, Díaz-Astudillo P, Corrales-Orovio R, San Martín S, Egaña JT. Comprehensive Characterization of Tissues Derived from Animals at Different Regenerative Stages: A Comparative Analysis between Fetal and Adult Mouse Skin. Cells 2023; 12:cells12091215. [PMID: 37174615 PMCID: PMC10177150 DOI: 10.3390/cells12091215] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/14/2023] [Accepted: 04/18/2023] [Indexed: 05/15/2023] Open
Abstract
Tissue regeneration capabilities vary significantly throughout an organism's lifespan. For example, mammals can fully regenerate until they reach specific developmental stages, after which they can only repair the tissue without restoring its original architecture and function. The high regenerative potential of fetal stages has been attributed to various factors, such as stem cells, the immune system, specific growth factors, and the presence of extracellular matrix molecules upon damage. To better understand the local differences between regenerative and reparative tissues, we conducted a comparative analysis of skin derived from mice at regenerative and reparative stages. Our findings show that both types of skin differ in their molecular composition, structure, and functionality. We observed a significant increase in cellular density, nucleic acid content, neutral lipid density, Collagen III, and glycosaminoglycans in regenerative skin compared with reparative skin. Additionally, regenerative skin had significantly higher porosity, metabolic activity, water absorption capacity, and elasticity than reparative skin. Finally, our results also revealed significant differences in lipid distribution, extracellular matrix pore size, and proteoglycans between the two groups. This study provides comprehensive data on the molecular and structural clues that enable full tissue regeneration in fetal stages, which could aid in developing new biomaterials and strategies for tissue engineering and regeneration.
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Affiliation(s)
- Valentina Castillo
- Institute for Biological and Medical Engineering, Schools of Engineering, Biological Sciences, and Medicine, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Pamela Díaz-Astudillo
- Biomedical Research Center, School of Medicine, Universidad de Valparaiso, Valparaiso 2540064, Chile
| | - Rocío Corrales-Orovio
- Institute for Biological and Medical Engineering, Schools of Engineering, Biological Sciences, and Medicine, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, LMU Munich, 81377 Munich, Germany
| | - Sebastián San Martín
- Biomedical Research Center, School of Medicine, Universidad de Valparaiso, Valparaiso 2540064, Chile
| | - José Tomás Egaña
- Institute for Biological and Medical Engineering, Schools of Engineering, Biological Sciences, and Medicine, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
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5
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Kaur H, Sharma P, Pal VK, Sen S, Roy S. Exploring Supramolecular Interactions between the Extracellular-Matrix-Derived Minimalist Bioactive Peptide and Nanofibrillar Cellulose for the Development of an Advanced Biomolecular Scaffold. ACS Biomater Sci Eng 2023; 9:1422-1436. [PMID: 36826412 DOI: 10.1021/acsbiomaterials.3c00014] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
It has been increasingly evident over the last few years that bioactive peptide hydrogels in conjugation with polymer hydrogels are emerging as a new class of supramolecular materials suitable for various biomedical applications owing to their specificity, tunability, and nontoxicity toward the biological system. Despite their unique biocompatible features, both polymer- and peptide-based scaffolds suffer from certain limitations, which restrict their use toward developing efficient matrices for controlling cellular behavior. The peptide hydrogels usually form soft matrices with low mechanical strength, whereas most of the polymer hydrogels lack biofunctionality. In this direction, combining polymers with peptides to develop a conjugate hydrogel can be explored as an emergent approach to overcome the limitations of the individual components. The polymer will provide high mechanical strength, whereas the biofunctionality of the material can be induced by the bioactive peptide sequence. In this study, we utilized TEMPO-oxidized nanofibrillar cellulose as the polymer counterpart, which was co-assembled with a short N-cadherin mimetic bioactive peptide sequence, Nap-HAVDI, to fabricate an NFC-peptide conjugate hydrogel. Interestingly, the mechanical strength of the peptide hydrogel was found to be significantly improved by combining the peptide with the NFC in the conjugate hydrogel. The addition of the peptide into the NFC also reduced the pore size within NFC matrices, which further helped in improving cellular adhesion, survival, and proliferation. Furthermore, the cells grown on the NFC and NFC-peptide hybrid hydrogel demonstrated normal expression of cytoskeleton proteins, i.e., β-tubulin in C6 cells and actin in L929 cells, respectively. The selective response of neuronal cells toward the specific bioactive peptide was further observed through a protein expression study. Thus, our study demonstrated the collective role of the cellulose-peptide composite material that revealed superior physical properties and biological response of this composite scaffold, which may open up a new platform for biomedical applications.
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Affiliation(s)
- Harsimran Kaur
- Institute of Nano Science and Technology (INST), Sector 81, Knowledge City, Mohali, Punjab 140306, India
| | - Pooja Sharma
- Institute of Nano Science and Technology (INST), Sector 81, Knowledge City, Mohali, Punjab 140306, India
| | - Vijay K Pal
- Institute of Nano Science and Technology (INST), Sector 81, Knowledge City, Mohali, Punjab 140306, India
| | - Sourav Sen
- Institute of Nano Science and Technology (INST), Sector 81, Knowledge City, Mohali, Punjab 140306, India
| | - Sangita Roy
- Institute of Nano Science and Technology (INST), Sector 81, Knowledge City, Mohali, Punjab 140306, India
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6
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Mohabatpour F, Duan X, Yazdanpanah Z, Tabil XL, Lobanova L, Zhu N, Papagerakis S, Chen X, Papagerakis P. Bioprinting of alginate-carboxymethyl chitosan scaffolds for enamel tissue engineering in vitro. Biofabrication 2022; 15. [PMID: 36583240 DOI: 10.1088/1758-5090/acab35] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 12/13/2022] [Indexed: 12/14/2022]
Abstract
Tissue engineering offers a great potential in regenerative dentistry and to this end, three dimensional (3D) bioprinting has been emerging nowadays to enable the incorporation of living cells into the biomaterials (such a mixture is referred as a bioink in the literature) to create scaffolds. However, the bioinks available for scaffold bioprinting are limited, particularly for dental tissue engineering, due to the complicated, yet compromised, printability, mechanical and biological properties simultaneously imposed on the bioinks. This paper presents our study on the development of a novel bioink from carboxymethyl chitosan (CMC) and alginate (Alg) for bioprinting scaffolds for enamel tissue regeneration. CMC was used due to its antibacterial ability and superior cell interaction properties, while Alg was added to enhance the printability and mechanical properties as well as to regulate the degradation rate. The bioinks with three mixture ratios of Alg and CMC (2-4, 3-3 and 4-2) were prepared, and then printed into the calcium chloride crosslinker solution (100 mM) to form a 3D structure of scaffolds. The printed scaffolds were characterized in terms of structural, swelling, degradation, and mechanical properties, followed by theirin vitrocharacterization for enamel tissue regeneration. The results showed that the bioinks with higher concentrations of Alg were more viscous and needed higher pressure for printing; while the printed scaffolds were highly porous and showed a high degree of printability and structural integrity. The hydrogels with higher CMC ratios had higher swelling ratios, faster degradation rates, and lower compressive modulus. Dental epithelial cell line, HAT-7, could maintain high viability in the printed constructs after 1, 7 and 14 d of culture. HAT-7 cells were also able to maintain their morphology and secrete alkaline phosphatase after 14 d of culture in the 3D printed scaffolds, suggesting the capacity of these cells for mineral deposition and enamel-like tissue formation. Among all combinations Alg4%-CMC2% and in a less degree 2%Alg-4%CMC showed the higher potential to promote ameloblast differentiation, Ca and P deposition and matrix mineralizationin vitro. Taken together, Alg-CMC has been illustrated to be suitable to print scaffolds with dental epithelial cells for enamel tissue regeneration.
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Affiliation(s)
- Fatemeh Mohabatpour
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada.,College of Dentistry, University of Saskatchewan, 105 Wiggins Rd, Saskatoon S7N 5E4 SK, Canada
| | - Xiaoman Duan
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada
| | - Zahra Yazdanpanah
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada
| | - Xavier Lee Tabil
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada
| | - Liubov Lobanova
- College of Dentistry, University of Saskatchewan, 105 Wiggins Rd, Saskatoon S7N 5E4 SK, Canada
| | - Ning Zhu
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada.,Canadian Light Source, University of Saskatchewan, 44 Innovation Blvd, Saskatoon S7N2V3 SK, Canada
| | - Silvana Papagerakis
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada.,Department of Surgery, College of Medicine, University of Saskatchewan, 107 Wiggins Rd, Saskatoon S7N 0W8 SK, Canada
| | - Xiongbiao Chen
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada.,Department of Mechanical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada
| | - Petros Papagerakis
- Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Dr, Saskatoon S7N 5A9 SK, Canada.,College of Dentistry, University of Saskatchewan, 105 Wiggins Rd, Saskatoon S7N 5E4 SK, Canada
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7
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Geevarghese R, Sajjadi SS, Hudecki A, Sajjadi S, Jalal NR, Madrakian T, Ahmadi M, Włodarczyk-Biegun MK, Ghavami S, Likus W, Siemianowicz K, Łos MJ. Biodegradable and Non-Biodegradable Biomaterials and Their Effect on Cell Differentiation. Int J Mol Sci 2022; 23:ijms232416185. [PMID: 36555829 PMCID: PMC9785373 DOI: 10.3390/ijms232416185] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 12/05/2022] [Accepted: 12/09/2022] [Indexed: 12/23/2022] Open
Abstract
Biomaterials for tissue scaffolds are key components in modern tissue engineering and regenerative medicine. Targeted reconstructive therapies require a proper choice of biomaterial and an adequate choice of cells to be seeded on it. The introduction of stem cells, and the transdifferentiation procedures, into regenerative medicine opened a new era and created new challenges for modern biomaterials. They must not only fulfill the mechanical functions of a scaffold for implanted cells and represent the expected mechanical strength of the artificial tissue, but furthermore, they should also assure their survival and, if possible, affect their desired way of differentiation. This paper aims to review how modern biomaterials, including synthetic (i.e., polylactic acid, polyurethane, polyvinyl alcohol, polyethylene terephthalate, ceramics) and natural (i.e., silk fibroin, decellularized scaffolds), both non-biodegradable and biodegradable, could influence (tissue) stem cells fate, regulate and direct their differentiation into desired target somatic cells.
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Affiliation(s)
- Rency Geevarghese
- Biotechnology Center, Silesian University of Technology, 44-100 Gliwice, Poland
| | - Seyedeh Sara Sajjadi
- School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran 1971653313, Iran
| | - Andrzej Hudecki
- Łukasiewicz Network-Institute of Non-Ferrous Metals, 44-121 Gliwice, Poland
| | - Samad Sajjadi
- School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran 1971653313, Iran
| | | | - Tayyebeh Madrakian
- Faculty of Chemistry, Bu-Ali Sina University, Hamedan 6516738695, Iran
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Mazaher Ahmadi
- Faculty of Chemistry, Bu-Ali Sina University, Hamedan 6516738695, Iran
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Małgorzata K. Włodarczyk-Biegun
- Biotechnology Center, Silesian University of Technology, 44-100 Gliwice, Poland
- Polymer Science, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Saeid Ghavami
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Department of Human Anatomy and Cell Science, University of Manitoba College of Medicine, Winnipeg, MB R3E 0V9, Canada
- Research Institutes of Oncology and Hematology, Cancer Care Manitoba-University of Manitoba, Winnipeg, MB R3E 0V9, Canada
- Biology of Breathing Theme, Children Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
- Faculty of Medicine in Zabrze, University of Technology in Katowice, 41-800 Zabrze, Poland
| | - Wirginia Likus
- Department of Anatomy, Faculty of Health Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
| | - Krzysztof Siemianowicz
- Department of Biochemistry, Faculty of Medicine in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
- Correspondence: (K.S.); (M.J.Ł.); Tel.: +48-32-237-2913 (M.J.Ł.)
| | - Marek J. Łos
- Biotechnology Center, Silesian University of Technology, 44-100 Gliwice, Poland
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Correspondence: (K.S.); (M.J.Ł.); Tel.: +48-32-237-2913 (M.J.Ł.)
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8
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Rickel AP, Sanyour HJ, Kinser C, Khatiwada N, Vogel H, Hong Z. Exploring the difference in the mechanics of vascular smooth muscle cells from wild-type and apolipoprotein-E knockout mice. Am J Physiol Cell Physiol 2022; 323:C1393-C1401. [PMID: 36121132 PMCID: PMC9602701 DOI: 10.1152/ajpcell.00046.2022] [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: 02/03/2022] [Revised: 08/30/2022] [Accepted: 09/14/2022] [Indexed: 11/22/2022]
Abstract
Atherosclerosis-related cardiovascular diseases are a leading cause of mortality worldwide. Vascular smooth muscle cells (VSMCs) comprise the medial layer of the arterial wall and undergo phenotypic switching during atherosclerosis to a synthetic phenotype capable of proliferation and migration. The surrounding environment undergoes alterations in extracellular matrix (ECM) stiffness and composition and an increase in cholesterol content. Using an atherosclerotic murine model, we analyzed how the mechanics of VSMCs isolated from Western diet-fed apolipoprotein-E knockout (ApoE-/-) and wild-type (WT) mice were altered during atherosclerosis. Increased stiffness of ApoE-/- VSMCs correlated with a greater degree of stress fiber alignment, as evidenced by atomic force microscopy (AFM)-generated force maps and stress fiber topography images. On type-1 collagen (COL1)-coated polyacrylamide (PA) gels (referred to as substrate) of varying stiffness, ApoE-/- VSMCs had lower adhesion forces to COL1 and N-cadherin (N-Cad) compared with WT cells. ApoE-/- VSMC stiffness was significantly greater than that of WT cells. Cell stiffness increased with increasing substrate stiffness for both ApoE-/- and WT VSMCs. In addition, ApoE-/- VSMCs showed an enhanced migration capability on COL1-coated substrates and a general decreasing trend in migration capacity with increasing substrate stiffness, correlating with lowered adhesion forces as compared with WT VSMCs. Altogether, these results demonstrate the potential contribution of the alteration in VSMC mechanics in the development of atherosclerosis.
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Affiliation(s)
- Alex P Rickel
- Biomedical Engineering Department, University of South Dakota, Sioux Falls, South Dakota
| | - Hanna J Sanyour
- Biomedical Engineering Department, University of South Dakota, Sioux Falls, South Dakota
| | - Courtney Kinser
- Biomedical Engineering Department, University of South Dakota, Sioux Falls, South Dakota
| | - Nisha Khatiwada
- Biomedical Engineering Department, University of South Dakota, Sioux Falls, South Dakota
- Mechanical Engineering Department, Texas Tech University, Lubbock, Texas
| | - Hayley Vogel
- Biomedical Engineering Department, University of South Dakota, Sioux Falls, South Dakota
| | - Zhongkui Hong
- Biomedical Engineering Department, University of South Dakota, Sioux Falls, South Dakota
- Mechanical Engineering Department, Texas Tech University, Lubbock, Texas
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9
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Jia W, Liu L, Li M, Zhou Y, Zhou H, Weng H, Gu G, Xiao M, Chen Z. Construction of enzyme-laden vascular scaffolds based on hyaluronic acid oligosaccharides-modified collagen nanofibers for antithrombosis and in-situ endothelialization of tissue-engineered blood vessels. Acta Biomater 2022; 153:287-298. [PMID: 36155095 DOI: 10.1016/j.actbio.2022.09.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/29/2022]
Abstract
The current use of synthetic grafts often yields low patency in the reconstruction of small-diameter blood vessels owing to the deposition of thrombi and imperfect coverage of the endothelium on the graft lumen. Therefore, the design of vascular scaffolds with antithrombotic performance and endothelialization is greatly required. Herein, we developed an enzyme-laden scaffold based on hyaluronic acid oligosaccharides-modified collagen nanofibers (labeled HA-COL) to improve the anti-platelet capacity and endothelialization of vascular grafts. In this study, HA-COL nanofibers not only encouraged the endothelialization of vascular scaffolds, but acted as an antiplatelet enzyme-laden platform. Apyrase (Apy) and 5'-nucleotidase (5'-NT) were covalently grafted onto the nanofibers, which in turn converted the platelet-sensitive substance: adenosine diphosphate (ADP) into adenosine monophosphate (AMP) and adenosine, thereby, improving the antithrombotic performance of the scaffolds. Notably, the catalytic end-product: adenosine would work in coordination with HA-COL to synergistically enhance the endothelialization of the vascular scaffolds. The results demonstrated that the enzyme-laden scaffolds maintained catalytic performance, reduced platelet adhesion and aggregation, and guaranteed higher patency after 1-month in situ transplantation. Moreover, these scaffolds showed optimal cytocompatibility, tissue compatibility, scaffold biodegradability and tissue regenerative capability during in vivo implantation. Overall, these engineered vascular scaffolds demonstrated their capacity for endothelialization and antithrombotic performance, suggesting their potential for small-diameter vascular tissue engineering applications. STATEMENT OF SIGNIFICANCE: Considering the critical problems in small-diameter vascular reconstruction, the enzyme-laden vascular scaffolds were prepared for improving in-situ endothelialization and antithrombotic performances of artificial blood vessels. The electrospun HA-COL nanofibers were used as the main matrix materials, which provided favorable structural templates for the regeneration of vasculature and functioned as a platform for the loading of enzymes. The enzyme-laden scaffolds with the biomimetic cascading reaction would convert ADP into adenosine, thereby, decreasing the sensitivity of platelets and improving the antithrombotic performance of tissue-engineered blood vessels (TEBVs). The nanofibrous scaffolds exhibited optimal cytocompatibility, tissue compatibility and regenerative capability, working together with catalytic products of dual-enzyme reaction that would synergistically contribute to TEBVs endothelialization. This study provides a new method for the improvement of in-situ endothelialization of small-diameter TEBVs while qualified with antithrombotic performance.
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Affiliation(s)
- Weibin Jia
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China; Hong Kong Centre for Cerebro-Cardiovascular Health Engineering, Hong Kong 999077, China
| | - Liling Liu
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China
| | - Min Li
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China
| | - Yuanmeng Zhou
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China
| | - Hang Zhou
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China
| | - Hongjuan Weng
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China
| | - Guofeng Gu
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China
| | - Min Xiao
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China
| | - Zonggang Chen
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine, Shandong University, Qingdao, 266237, China.
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10
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Zhang X, Xiao L, Ding Z, Lu Q, Kaplan DL. Engineered Tough Silk Hydrogels through Assembling β-Sheet Rich Nanofibers Based on a Solvent Replacement Strategy. ACS NANO 2022; 16:10209-10218. [PMID: 35587205 DOI: 10.1021/acsnano.2c01616] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
β-Sheet rich silk nanofiber hydrogels are suitable scaffolds in tissue regeneration and carriers for various drugs. However, unsatisfactory mechanical performance limits its applications. Here, insight into the silk nanofibers stimulates the remodeling of previous solvent systems to actively regulate the assembly of silk nanofibers. Formic acid, a solvent of regenerated silk fibroin, is used to shield the charge repulsion of silk nanofibers to facilitate the nanofiber assembly under concentrated solutions. Formic acid was replaced with water to solidify the assembly, which induced the formation of a tough hydrogel. The hydrogels generated with this process possessed a modulus of 5.88 ± 0.82 MPa, ultimate stress of 1.55 ± 0.06 MPa, and toughness of 0.85 ± 0.03 MJ m-3, superior to those of previous silk hydrogels prepared through complex cross-linking processes. Benefiting from the dense gel network and high β-sheet content, these silk nanofiber hydrogels had good stability and antiswelling ability. The modulus could be modulated via changing the silk nanofiber concentration to provide differentiation signals to stem cells. Improved mechanical and bioactive properties with these hydrogels suggest utility in biomedical and engineering fields. More importantly, our present study reveals that the in-depth understanding of silk nanofibers could infuse power into traditional fabrication systems to achieve more high performance biomaterials, which is seldom considered in silk material studies.
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Affiliation(s)
- Xiaoyi Zhang
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China
| | - Liying Xiao
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China
| | - Zhaozhao Ding
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China
| | - Qiang Lu
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
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11
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Fan Z, Liu H, Shi S, Ding Z, Zhang Z, Lu Q, Kaplan DL. Anisotropic silk nanofiber layers as regulators of angiogenesis for optimized bone regeneration. Mater Today Bio 2022; 15:100283. [PMID: 35634170 PMCID: PMC9130114 DOI: 10.1016/j.mtbio.2022.100283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/06/2022] [Accepted: 05/08/2022] [Indexed: 11/16/2022] Open
Abstract
Osteogenesis-angiogenesis coupling processes play a crucial role in bone regeneration. Here, electric field induced aligned nanofiber layers with tunable thickness were coated on the surface of pore walls inside the deferoxamine (DFO)-laden silk fibroin (SF) and hydroxyapatite (HA) composite scaffolds to regulate the release of DFO to control vascularization dynamically. Longer electric field treatments resulted in gradually thickening layers to reduce the release rate of DFO where the released amount of DFO decreased gradually from 84% to 63% after 28 days. Besides the osteogenic capacity of HA, the changeable release of DFO brought different angiogenic behaviors in bone regeneration process, which provided a desirable niche with osteogenic and angiogenic cues. Anisotropic cues were introduced to facilitate cell migration inside the scaffolds. Changeable cytokine secretion from endothelial cells cultured in the different scaffolds revealed the regulation of cell responses related to vascularization in vitro. Peak expression of angiogenic factors appeared at days 7, 21 and 35 for endothelial cells cultured in the scaffolds with different silk nanofier layers, suggesting the dynamical regulation of angiogenesis. Although all of the scaffolds had the same silk and HA composition, in vitro cell studies indicated different osteogenic capacities for the scaffolds, suggesting that the regulation of DFO release also influenced osteogenesis outcomes in vitro. In vivo, the best bone regeneration occurred in defects treated with the composite scaffolds that exhibited the best osteogenic capacity in vitro. Using a rat bone defect model, healing was achieved within 12 weeks, superior to those treated with previous SF-HA composite matrices. Controlling angiogenic properties of bone biomaterials dynamically is an effective strategy to improve bone regeneration capacity. Anisotropic silk nanofiber layers with tunable thickness control the sustained release of DFO dynamically. Dynamical regulation of angiogenesis was achieved in bone regeneration process through tuning the release behaviors of DFO. Significantly improved bone regeneration through the synergistic effect of optimal vascularization and osteogenesis.
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Affiliation(s)
- Zhihai Fan
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Soochow University, Suzhou, 215000, PR China
| | - Hongxiang Liu
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Soochow University, Suzhou, 215000, PR China
| | - Shilei Shi
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Soochow University, Suzhou, 215000, PR China
| | - Zhaozhao Ding
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, PR China
- Corresponding author.
| | - Zhen Zhang
- Department of Dermatology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200011, PR China
| | - Qiang Lu
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, PR China
- Corresponding author.
| | - David L. Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, United States
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12
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Zhang X, Hang Y, Ding Z, Xiao L, Cheng W, Lu Q. Macroporous Silk Nanofiber Cryogels with Tunable Properties. Biomacromolecules 2022; 23:2160-2169. [PMID: 35443774 DOI: 10.1021/acs.biomac.2c00222] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cryogels are widely used in tissue regeneration due to their porous structures and friendly hydrogel performance. Silk-based cryogels were developed but failed to exhibit desirable tunable properties to adapt various biomedical applications. Here, amorphous short silk nanofibers (SSFs) were introduced to fabricate silk cryogels with versatile cues. Compared to previous silk cryogels, the SSF cryogels prepared under same conditions showed significantly enhanced mechanical properties. The microporous cryogels were achieved under lower silk concentrations, confirming better tunability. Versatile cryogels with the modulus in the range of 0.5-283.7 kPa were developed through adjusting silk concentration and crosslinking conditions, superior to previous silk cryogel systems. Besides better cytocompatibility, the SSF cryogels were endowed with effective mechanical cues to control osteogenetic differentiation behaviors of BMSCs. The mechanical properties could be further regulated finely through the introduction of β-sheet-rich silk nanofibers (SNFs), which suggested possible optimization of mechanical niches. Bioactive cargo-laden SNFs were introduced to the SSF cryogel systems, bringing biochemical signals without the compromise of mechanical properties. Versatile SNF-based cryogels with different physical and biological cues were developed here to facilitate the applications in various tissue engineering.
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Affiliation(s)
- Xiaoyi Zhang
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, People's Republic of China
| | - Yingjie Hang
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, People's Republic of China
| | - Zhaozhao Ding
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, People's Republic of China
| | - Liying Xiao
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, People's Republic of China
| | - Weinan Cheng
- Department of Orthopedics, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361000, People's Republic of China
| | - Qiang Lu
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, People's Republic of China
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13
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Scaffold Pore Curvature Influences ΜSC Fate through Differential Cellular Organization and YAP/TAZ Activity. Int J Mol Sci 2022; 23:ijms23094499. [PMID: 35562890 PMCID: PMC9102667 DOI: 10.3390/ijms23094499] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/15/2022] [Accepted: 04/16/2022] [Indexed: 12/12/2022] Open
Abstract
Tissue engineering aims to repair, restore, and/or replace tissues in the human body as an alternative to grafts and prostheses. Biomaterial scaffolds can be utilized to provide a three-dimensional microenvironment to facilitate tissue regeneration. Previously, we reported that scaffold pore size influences vascularization and extracellular matrix composition both in vivo and in vitro, to ultimately influence tissue phenotype for regenerating cranial suture and bone tissues, which have markedly different tissue properties despite similar multipotent stem cell populations. To rationally design biomaterials for specific cell and tissue fate specification, it is critical to understand the molecular processes governed by cell-biomaterial interactions, which guide cell fate specification. Building on our previous work, in this report we investigated the hypothesis that scaffold pore curvature, the direct consequence of pore size, modulates the differentiation trajectory of mesenchymal stem cells (MSCs) through alterations in the cytoskeleton. First, we demonstrated that sufficiently small pores facilitate cell clustering in subcutaneous explants cultured in vivo, which we previously reported to demonstrate stem tissue phenotype both in vivo and in vitro. Based on this observation, we cultured cell-scaffold constructs in vitro to assess early time point interactions between cells and the matrix as a function of pore size. We demonstrate that principle curvature directly influences nuclear aspect and cell aggregation in vitro. Scaffold pores with a sufficiently low degree of principle curvature enables cell differentiation; pharmacologic inhibition of actin cytoskeleton polymerization in these scaffolds decreased differentiation, indicating a critical role of the cytoskeleton in transducing cues from the scaffold pore microenvironment to the cell nucleus. We fabricated a macropore model, which allows for three-dimensional confocal imaging and demonstrates that a higher principle curvature facilitates cell aggregation and the formation of a potentially protective niche within scaffold macropores which prevents MSC differentiation and retains their stemness. Sufficiently high principle curvature upregulates yes-associated protein (YAP) phosphorylation while decreased principle curvature downregulates YAP phosphorylation and increases YAP nuclear translocation with subsequent transcriptional activation towards an osteogenic differentiation fate. Finally, we demonstrate that the inhibition of the YAP/TAZ pathway causes a defect in differentiation, while YAP/TAZ activation causes premature differentiation in a curvature-dependent way when modulated by verteporfin (VP) and 1-oleyl-lysophosphatidic acid (LPA), respectively, confirming the critical role of biomaterials-mediated YAP/TAZ signaling in cell differentiation and fate specification. Our data support that the principle curvature of scaffold macropores is a critical design criterion which guides the differentiation trajectory of mesenchymal stem cells’ scaffolds. Biomaterial-mediated regulation of YAP/TAZ may significantly contribute to influencing the regenerative outcomes of biomaterials-based tissue engineering strategies through their specific pore design.
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14
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Tian KK, Huang SC, Xia XX, Qian ZG. Fibrous Structure and Stiffness of Designer Protein Hydrogels Synergize to Regulate Endothelial Differentiation of Bone Marrow Mesenchymal Stem Cells. Biomacromolecules 2022; 23:1777-1788. [PMID: 35312276 DOI: 10.1021/acs.biomac.2c00032] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Matrix stiffness and fibrous structure provided by the native extracellular matrix have been increasingly appreciated as important cues in regulating cell behaviors. Recapitulating these physical cues for cell fate regulation remains a challenge due to the inherent difficulties in making mimetic hydrogels with well-defined compositions, tunable stiffness, and structures. Here, we present two series of fibrous and porous hydrogels with tunable stiffness based on genetically engineered resilin-silk-like and resilin-like protein polymers. Using these hydrogels as substrates, the mechanoresponses of bone marrow mesenchymal stem cells to stiffness and fibrous structure were systematically studied. For both hydrogel series, increasing compression modulus from 8.5 to 14.5 and 23 kPa consistently promoted cell proliferation and differentiation. Nonetheless, the promoting effects were more pronounced on the fibrous gels than their porous counterparts at all three stiffness levels. More interestingly, even the softest fibrous gel (8.5 kPa) allowed the stem cells to exhibit higher endothelial differentiation capability than the toughest porous gel (23 kPa). The predominant role of fibrous structure on the synergistic regulation of endothelial differentiation was further explored. It was found that the stiffness signal activated Yes-associated protein (YAP), the main regulator of endothelial differentiation, via spreading of focal adhesions, whereas fibrous structure reinforced YAP activation by promoting the maturation of focal adhesions and associated F-actin alignment. Therefore, our results shed light on the interplay of physical cues in regulating stem cells and may guide the fabrication of designer proteinaceous matrices toward regenerative medicine.
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Affiliation(s)
- Kai-Kai Tian
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Sheng-Chen Huang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Xiao-Xia Xia
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Zhi-Gang Qian
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
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15
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Guo P, Du P, Zhao P, Chen X, Liu C, Du Y, Li J, Tang X, Yang F, Lv G. Regulating the mechanics of silk fibroin scaffolds promotes wound vascularization. Biochem Biophys Res Commun 2021; 574:78-84. [PMID: 34438350 DOI: 10.1016/j.bbrc.2021.08.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 07/25/2021] [Accepted: 08/09/2021] [Indexed: 01/13/2023]
Abstract
Functional blood vessels are crucial to wound healing, and faster vascularization means faster tissue repair to some extent. Increasing numbers of pro-vascularization wound coverings are being developed and studied. Moreover, mechanical properties of the extracellular matrix can guide the behaviour of related cells to some degree. Studies have shown that the mechanical range of 1-7 kPa contributes to the differentiation of stem cells into endothelial cells and thus to the process of wound vascularization. Unfortunately, the regulatory mechanics of vascularizing wound coverings have been poorly studied. Silk fibroin (SF) has attracted much attention because of its good biocompatibility, degradability and adjustable mechanical properties. In this paper, silk scaffolds with mechanical properties of 2 kPa and 5.9 kPa were prepared by adjusting the mechanics of silk scaffolds in terms of freezing temperature and aligned structure. The mechanical properties of the 5.9 kPa aligned silk scaffold (ASS) showed good vascularization ability. By adjusting the intermediate conformation and physical structure of Silk fibroin (SF), the mechanical strength of the silk scaffold could be increased, enabling us to better understand the mechanical regulation mode. At the same time, the aligned structure of the aligned silk scaffold (ASS) promoted the migration and proliferation of cells related to wound repair to a certain extent. By adjusting the mechanical properties and physical structure of the material, an aligned silk scaffold with vascularization function was constructed, providing more possibilities for faster wound repair.
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Affiliation(s)
- Peng Guo
- The University of Nantong, NanTong City, Jiangsu, 226000, China
| | - Pan Du
- The University of Jiangnan, WuXi City, Jiangsu, 214000, China
| | - Peng Zhao
- The Affiliated Hospital of Jiangnan University, Jiangsu, 214000, China
| | - Xue Chen
- The University of Jiangnan, WuXi City, Jiangsu, 214000, China
| | - Chenyang Liu
- Nanjing University of Chinese Medicine, Jiangsu, 210023, China
| | - Yong Du
- The University of Nantong, NanTong City, Jiangsu, 226000, China
| | - Jiadai Li
- The University of Nantong, NanTong City, Jiangsu, 226000, China
| | - Xiaoyu Tang
- The University of Nantong, NanTong City, Jiangsu, 226000, China
| | - Fengbo Yang
- The University of Nantong, NanTong City, Jiangsu, 226000, China
| | - Guozhong Lv
- The Affiliated Hospital of Jiangnan University, Jiangsu, 214000, China.
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16
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Hu Y, Yang Y, Tian F, Xu P, Du R, Xia X, Xu S. Fabrication of Stiffness Gradient Nanocomposite Hydrogels for Mimicking Cell Microenvironment. Macromol Res 2021. [DOI: 10.1007/s13233-021-9056-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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17
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Kochhar D, DeBari MK, Abbott RD. The Materiobiology of Silk: Exploring the Biophysical Influence of Silk Biomaterials on Directing Cellular Behaviors. Front Bioeng Biotechnol 2021; 9:697981. [PMID: 34239865 PMCID: PMC8259510 DOI: 10.3389/fbioe.2021.697981] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/31/2021] [Indexed: 11/13/2022] Open
Abstract
Biophysical properties of the extracellular environment dynamically regulate cellular fates. In this review, we highlight silk, an indispensable polymeric biomaterial, owing to its unique mechanical properties, bioactive component sequestration, degradability, well-defined architectures, and biocompatibility that can regulate temporospatial biochemical and biophysical responses. We explore how the materiobiology of silks, both mulberry and non-mulberry based, affect cell behaviors including cell adhesion, cell proliferation, cell migration, and cell differentiation. Keeping in mind the novel biophysical properties of silk in film, fiber, or sponge forms, coupled with facile chemical decoration, and its ability to match functional requirements for specific tissues, we survey the influence of composition, mechanical properties, topography, and 3D geometry in unlocking the body's inherent regenerative potential.
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Affiliation(s)
- Dakshi Kochhar
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Megan K. DeBari
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Rosalyn D. Abbott
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
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18
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Baruffaldi D, Palmara G, Pirri C, Frascella F. 3D Cell Culture: Recent Development in Materials with Tunable Stiffness. ACS APPLIED BIO MATERIALS 2021; 4:2233-2250. [PMID: 35014348 DOI: 10.1021/acsabm.0c01472] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
It is widely accepted that three-dimensional cell culture systems simulate physiological conditions better than traditional 2D systems. Although extracellular matrix components strongly modulate cell behavior, several studies underlined the importance of mechanosensing in the control of different cell functions such as growth, proliferation, differentiation, and migration. Human tissues are characterized by different degrees of stiffness, and various pathologies (e.g., tumor or fibrosis) cause changes in the mechanical properties through the alteration of the extracellular matrix structure. Additionally, these modifications have an impact on disease progression and on therapy response. Hence, the development of platforms whose stiffness could be modulated may improve our knowledge of cell behavior under different mechanical stress stimuli. In this review, we have analyzed the mechanical diversity of healthy and diseased tissues, and we have summarized recently developed materials with a wide range of stiffness.
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Affiliation(s)
- Désirée Baruffaldi
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy.,PolitoBIOMed Lab, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy
| | - Gianluca Palmara
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy.,PolitoBIOMed Lab, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy
| | - Candido Pirri
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy.,PolitoBIOMed Lab, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy.,Center for Sustainable Futures@Polito, Istituto Italiano di Tecnologia, Via Livorno 60, Turin 10144, Italy
| | - Francesca Frascella
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy.,PolitoBIOMed Lab, Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin 10129, Italy
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19
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Brouns JP, Dankers PYW. Introduction of Enzyme-Responsivity in Biomaterials to Achieve Dynamic Reciprocity in Cell-Material Interactions. Biomacromolecules 2021; 22:4-23. [PMID: 32813514 PMCID: PMC7805013 DOI: 10.1021/acs.biomac.0c00930] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/19/2020] [Indexed: 12/11/2022]
Abstract
Much effort has been made in the development of biomaterials that synthetically mimic the dynamics of the natural extracellular matrix in tissues. Most of these biomaterials specifically interact with cells, but lack the ability to adapt and truly communicate with the cellular environment. Communication between biomaterials and cells is achieved by the development of various materials with enzyme-responsive moieties in order to respond to cellular cues. In this perspective, we discuss different enzyme-responsive systems, from surfaces to supramolecular assemblies. Additionally, we highlight their further prospects in order to create, inspired by nature, fully autonomous adaptive biomaterials that display dynamic reciprocal behavior. This Perspective shows new strategies for the development of biomaterials that may find broad utility in regenerative medicine applications, from scaffolds for tissue engineering to systems for controlled drug delivery.
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Affiliation(s)
- Joyce
E. P. Brouns
- Eindhoven University of
Technology, Institute for Complex
Molecular Systems, Department of Biomedical Engineering, Laboratory
of Chemical Biology, Het
Kranenveld 14, 5612 AZ, Eindhoven, The Netherlands
| | - Patricia Y. W. Dankers
- Eindhoven University of
Technology, Institute for Complex
Molecular Systems, Department of Biomedical Engineering, Laboratory
of Chemical Biology, Het
Kranenveld 14, 5612 AZ, Eindhoven, The Netherlands
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20
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Rahmati M, Silva EA, Reseland JE, A Heyward C, Haugen HJ. Biological responses to physicochemical properties of biomaterial surface. Chem Soc Rev 2020; 49:5178-5224. [PMID: 32642749 DOI: 10.1039/d0cs00103a] [Citation(s) in RCA: 137] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Biomedical scientists use chemistry-driven processes found in nature as an inspiration to design biomaterials as promising diagnostic tools, therapeutic solutions, or tissue substitutes. While substantial consideration is devoted to the design and validation of biomaterials, the nature of their interactions with the surrounding biological microenvironment is commonly neglected. This gap of knowledge could be owing to our poor understanding of biochemical signaling pathways, lack of reliable techniques for designing biomaterials with optimal physicochemical properties, and/or poor stability of biomaterial properties after implantation. The success of host responses to biomaterials, known as biocompatibility, depends on chemical principles as the root of both cell signaling pathways in the body and how the biomaterial surface is designed. Most of the current review papers have discussed chemical engineering and biological principles of designing biomaterials as separate topics, which has resulted in neglecting the main role of chemistry in this field. In this review, we discuss biocompatibility in the context of chemistry, what it is and how to assess it, while describing contributions from both biochemical cues and biomaterials as well as the means of harmonizing them. We address both biochemical signal-transduction pathways and engineering principles of designing a biomaterial with an emphasis on its surface physicochemistry. As we aim to show the role of chemistry in the crosstalk between the surface physicochemical properties and body responses, we concisely highlight the main biochemical signal-transduction pathways involved in the biocompatibility complex. Finally, we discuss the progress and challenges associated with the current strategies used for improving the chemical and physical interactions between cells and biomaterial surface.
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Affiliation(s)
- Maryam Rahmati
- Department of Biomaterials, Institute of Clinical Dentistry, University of Oslo, 0317 Oslo, Norway. h.j.haugen.odont.uio.no
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21
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Zheng X, Ding Z, Cheng W, Lu Q, Kong X, Zhou X, Lu G, Kaplan DL. Microskin-Inspired Injectable MSC-Laden Hydrogels for Scarless Wound Healing with Hair Follicles. Adv Healthc Mater 2020; 9:e2000041. [PMID: 32338466 PMCID: PMC7473495 DOI: 10.1002/adhm.202000041] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 03/26/2020] [Indexed: 12/20/2022]
Abstract
Scarless skin regeneration with functional tissue remains a challenge for full-thickness wounds. Here, mesenchymal stem cell (MSC)-laden hydrogels are developed for scarless wound healing with hair follicles. Microgels composed of aligned silk nanofibers are used to load MSCs to modulate the paracrine. MSC-laden microgels are dispersed into injectable silk nanofiber hydrogels, forming composites biomaterials containing the cells. The injectable hydrogels protect and stabilize the MSCs in the wounds. The synergistic action of silk-based composite hydrogels and MSCs stimulated angiogenesis and M1-M2 phenotype switching of macrophages, provides a suitable niche for functional recovery of wounds. Compared to skin defects treated with MSC-free hydrogels, the defects treated with the MSC-laden composite hydrogels heal faster and form scarless tissues with hair follicles. Wound healing can be further improved by adjusting the ratio of silk nanofibers and particles and the loaded MSCs, suggesting tunability of the system. To the best of current knowledge, this is the first time scarless skin regeneration with hair follicles based on silk material systems is reported. The improved wound healing capacity of the systems suggests future in vivo studies to compare to other biomaterial systems related to clinical goals in skin regeneration in the absence of scarring.
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Affiliation(s)
- Xin Zheng
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, 215000, P. R. China
- Department of Orthopedics, Taizhou Municipal Hospital, Taizhou, 318000, P. R. China
| | - Zhaozhao Ding
- Department of Burns and Plastic Surgery, The Affiliated Hospital of Jiangnan University, Wuxi, 214041, P. R. China
- Engineering Research Center of the Ministry of Education for Wound Repair Technology, Jiangnan University, Wuxi, 214041, P. R. China
| | - Weinan Cheng
- Department of Orthopedics, The First Affiliated Hospital of Xiamen University, Xiamen, 361000, P. R. China
| | - Qiang Lu
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, 215000, P. R. China
- Department of Burns and Plastic Surgery, The Affiliated Hospital of Jiangnan University, Wuxi, 214041, P. R. China
- Engineering Research Center of the Ministry of Education for Wound Repair Technology, Jiangnan University, Wuxi, 214041, P. R. China
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Xiangdong Kong
- Zhejiang-Mauritius Joint Research Center for Biomaterials and Tissue Engineering, School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou, 310018, P. R. China
| | - Xiaozhong Zhou
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, 215000, P. R. China
| | - Guozhong Lu
- Department of Burns and Plastic Surgery, The Affiliated Hospital of Jiangnan University, Wuxi, 214041, P. R. China
- Engineering Research Center of the Ministry of Education for Wound Repair Technology, Jiangnan University, Wuxi, 214041, P. R. China
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
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22
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Rickel AP, Sanyour HJ, Leyda NA, Hong Z. Extracellular Matrix Proteins and Substrate Stiffness Synergistically Regulate Vascular Smooth Muscle Cell Migration and Cortical Cytoskeleton Organization. ACS APPLIED BIO MATERIALS 2020; 3:2360-2369. [PMID: 34327310 PMCID: PMC8318011 DOI: 10.1021/acsabm.0c00100] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Vascular smooth muscle cell (VSMC) migration is a critical step in the progression of cardiovascular disease and aging. Migrating VSMCs encounter a highly heterogeneous environment with the varying extracellular matrix (ECM) composition due to the differential synthesis of collagen and fibronectin (FN) in different regions and greatly changing stiffness, ranging from the soft necrotic core of plaques to hard calcifications within blood vessel walls. In this study, we demonstrate an application of a two-dimensional (2D) model consisting of an elastically tunable polyacrylamide gel of varying stiffness and ECM protein coating to study VSMC migration. This model mimics the in vivo microenvironment that VSMCs experience within a blood vessel wall, which may help identify potential therapeutic targets for the treatment of atherosclerosis. We found that substrate stiffness had differential effects on VSMC migration on type 1 collagen (COL1) and FN-coated substrates. VSMCs on COL1-coated substrates showed significantly diminished migration distance on stiffer substrates, while on FN-coated substrates VSMCs had significantly increased migration distance. In addition, cortical stress fiber orientation increased in VSMCs cultured on more rigid COL1-coated substrates, while decreasing on stiffer FN-coated substrates. On both proteins, a more disorganized cytoskeletal architecture was associated with faster migration. Overall, these results demonstrate that different ECM proteins can cause substrate stiffness to have differential effects on VSMC migration in the progression of cardiovascular diseases and aging.
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Affiliation(s)
- Alex P Rickel
- Department of Biomedical Engineering, University of South Dakota, Sioux Falls, South Dakota 57107, United States; BIOSNTR, Sioux Falls, South Dakota 57107, United States
| | - Hanna J Sanyour
- Department of Biomedical Engineering, University of South Dakota, Sioux Falls, South Dakota 57107, United States; BIOSNTR, Sioux Falls, South Dakota 57107, United States
| | - Neil A Leyda
- Department of Chemical Engineering, South Dakota School of Mines & Technology, Rapid City, South Dakota 57701, United States
| | - Zhongkui Hong
- Department of Biomedical Engineering, University of South Dakota, Sioux Falls, South Dakota 57107, United States; BIOSNTR, Sioux Falls, South Dakota 57107, United States
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23
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Xu G, Ding Z, Lu Q, Zhang X, Zhou X, Xiao L, Lu G, Kaplan DL. Electric field-driven building blocks for introducing multiple gradients to hydrogels. Protein Cell 2020; 11:267-285. [PMID: 32048173 PMCID: PMC7093350 DOI: 10.1007/s13238-020-00692-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 01/14/2020] [Indexed: 01/25/2023] Open
Abstract
Gradient biomaterials are considered as preferable matrices for tissue engineering due to better simulation of native tissues. The introduction of gradient cues usually needs special equipment and complex process but is only effective to limited biomaterials. Incorporation of multiple gradients in the hydrogels remains challenges. Here, beta-sheet rich silk nanofibers (BSNF) were used as building blocks to introduce multiple gradients into different hydrogel systems through the joint action of crosslinking and electric field. The blocks migrated to the anode along the electric field and gradually stagnated due to the solution-hydrogel transition of the systems, finally achieving gradient distribution of the blocks in the formed hydrogels. The gradient distribution of the blocks could be tuned easily through changing different factors such as solution viscosity, which resulted in highly tunable gradient of mechanical cues. The blocks were also aligned under the electric field, endowing orientation gradient simultaneously. Different cargos could be loaded on the blocks and form gradient cues through the same crosslinking-electric field strategy. The building blocks could be introduced to various hydrogels such as Gelatin and NIPAM, indicating the universality. Complex niches with multiple gradient cues could be achieved through the strategy. Silk-based hydrogels with suitable mechanical gradients were fabricated to control the osteogenesis and chondrogenesis. Chondrogenic-osteogenic gradient transition was obtained, which stimulated the ectopic osteochondral tissue regeneration in vivo. The versatility and highly controllability of the strategy as well as multifunction of the building blocks reveal the applicability in complex tissue engineering and various interfacial tissues.
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Affiliation(s)
- Gang Xu
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, 215000, China
- Department of Orthopedics, Affiliated Hospital of Xuzhou Medical University, Lianyungang, 222061, China
| | - Zhaozhao Ding
- Department of Burns and Plastic Surgery, Engineering Research Center of the Ministry of Education for Wound Repair Technology, The Affiliated Hospital of Jiangnan University, Wuxi, 214041, China
| | - Qiang Lu
- Department of Burns and Plastic Surgery, Engineering Research Center of the Ministry of Education for Wound Repair Technology, The Affiliated Hospital of Jiangnan University, Wuxi, 214041, China.
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, China.
| | - Xiaoyi Zhang
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, China
| | - Xiaozhong Zhou
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, 215000, China.
| | - Liying Xiao
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, China
| | - Guozhong Lu
- Department of Burns and Plastic Surgery, Engineering Research Center of the Ministry of Education for Wound Repair Technology, The Affiliated Hospital of Jiangnan University, Wuxi, 214041, China.
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
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24
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Zhang X, Zhang Z, Xiao L, Ding Z, He J, Lu G, Lu Q, Kaplan DL. Natural Nanofiber Shuttles for Transporting Hydrophobic Cargo into Aqueous Solutions. Biomacromolecules 2020; 21:1022-1030. [PMID: 31935078 DOI: 10.1021/acs.biomac.9b01739] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hydrophobic biomolecules realize their functions in vivo in aqueous environments, often through a delicate balance of amphiphilicity and chaperones. Introducing exogenous hydrophobic biomolecules into in vivo aqueous systems is a challenge in drug delivery and regenerative medicine, where labile linkers, carriers, and fusions or chimeric molecules are often designed to facilitate such aqueous interfaces. Here, we utilize naturally derived silk nanofiber shuttles with the capacity to transport hydrophobic cargos directly into aqueous solutions. These nanofibers disperse in organic solvents and in aqueous solutions because of their inherent amphiphilicity, with enriched hydrophobicity and strategically interspersed negatively charged groups. Hydrophobic molecules loaded on these shuttles in organic solvent-water systems separated from the solvent after centrifugation. These concentrated hydrophobic molecule-loaded nanofibers could then be dispersed into aqueous solution directly without modification. These shuttle systems were effective for different hydrophobic molecules such as drugs, vitamins, and dyes. Improved biological stability and functions of hydrophobic cargos after loading on these nanofibers suggest potential applications in drug delivery, cosmetology, medical diagnosis, and related health fields, with a relatively facile process.
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Affiliation(s)
- Xiaoyi Zhang
- Department of Burns and Plastic Surgery , The Affiliated Hospital of Jiangnan University , Wuxi 214041 , China.,National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Zhen Zhang
- Department of Dermatology, Shanghai Ninth People's Hospital , Shanghai Jiaotong University School of Medicine , Shanghai 200011 , China
| | - Liying Xiao
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Zhaozhao Ding
- Department of Burns and Plastic Surgery , The Affiliated Hospital of Jiangnan University , Wuxi 214041 , China
| | - Jiuyang He
- CAS Engineering Laboratory for Nanozyme, Key Laboratory of Protein and Peptide Pharmaceutical, Institute of Biophysics , Chinese Academy of Sciences , Beijing 100101 , China
| | - Guozhong Lu
- Department of Burns and Plastic Surgery , The Affiliated Hospital of Jiangnan University , Wuxi 214041 , China
| | - Qiang Lu
- Department of Burns and Plastic Surgery , The Affiliated Hospital of Jiangnan University , Wuxi 214041 , China.,National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - David L Kaplan
- Department of Biomedical Engineering , Tufts University , Medford , Massachusetts 02155 , United States
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