1
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Mondal J, Chakraborty K, Bunggulawa EJ, An JM, Revuri V, Nurunnabi M, Lee YK. Recent advancements of hydrogels in immunotherapy: Breast cancer treatment. J Control Release 2024; 372:1-30. [PMID: 38849092 DOI: 10.1016/j.jconrel.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 05/21/2024] [Accepted: 06/01/2024] [Indexed: 06/09/2024]
Abstract
Breast cancer is the most prevalent cancer among women and the leading cause of cancer-related deaths in this population. Recent advances in Immunotherapy, or combined immunotherapy, offering a more targeted and less toxic approach, expand the survival rate of patients more than conventional treatment. Notably, hydrogels, a versatile platform provided promising avenues to combat breast cancer in preclinical studies and extended to clinical practices. With advantages such as the alternation of tumor microenvironment, immunomodulation, targeted delivery of therapeutic agents, and their sustained release at specific sites of interest, hydrogels can potentially be used for the treatment of breast cancer. This review highlights the advantages, mechanisms of action, stimuli-responsiveness properties, and recent advancements of hydrogels for treating breast cancer immunotherapy. Moreover, post-treatment and its clinical translations are discussed in this review. The integration of hydrogels in immunotherapy strategies may pave the way for more effective, personalized, and patient-friendly approaches to combat breast cancer, ultimately contributing to a brighter future for breast cancer patients.
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Affiliation(s)
- Jagannath Mondal
- 4D Convergence Technology Institute, Korea National University of Transportation, Jeungpyeong 27909, Republic of Korea; Department of Green Bioengineering, Korea National University of Transportation, Chungju 27470, Republic of Korea; Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Kushal Chakraborty
- Department of IT and Energy Convergence (BK21 FOUR), Korea National University of Transportation, Chungju 27469, Republic of Korea
| | - Edwin J Bunggulawa
- Department of Green Bioengineering, Korea National University of Transportation, Chungju 27470, Republic of Korea
| | - Jeong Man An
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Vishnu Revuri
- Department of Green Bioengineering, Korea National University of Transportation, Chungju 27470, Republic of Korea
| | - Md Nurunnabi
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas at El Paso, El Paso, TX 79902, United States; Biomedical Engineering Program, College of Engineering, University of Texas at El Paso, El Paso, TX 79968, United States.
| | - Yong-Kyu Lee
- 4D Convergence Technology Institute, Korea National University of Transportation, Jeungpyeong 27909, Republic of Korea; Department of Green Bioengineering, Korea National University of Transportation, Chungju 27470, Republic of Korea; Department of Chemical & Biological Engineering, Korea National University of Transportation, Chungju 27470, Republic of Korea.
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2
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Suwannakot P, Nemec S, Peres NG, Du EY, Kilian KA, Gaus K, Kavallaris M, Gooding JJ. Electrostatic Assembly of Multiarm PEG-Based Hydrogels as Extracellular Matrix Mimics: Cell Response in the Presence and Absence of RGD Cell Adhesive Ligands. ACS Biomater Sci Eng 2023; 9:1362-1376. [PMID: 36826383 DOI: 10.1021/acsbiomaterials.2c01252] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Synthetic hydrogels have been used widely as extracellular matrix (ECM) mimics due to the ability to control and mimic physical and biochemical cues observed in natural ECM proteins such as collagen, laminin, and fibronectin. Most synthetic hydrogels are formed via covalent bonding resulting in slow gelation which is incompatible with drop-on-demand 3D bioprinting of cells and injectable hydrogels for therapeutic delivery. Herein, we developed an electrostatically crosslinked PEG-based hydrogel system for creating high-throughput 3D in vitro models using synthetic hydrogels to mimic the ECM cancer environment. A 3-arm PEG-based polymer backbone was first modified with either permanent cationic charged moieties (2-(methacryloyloxy)ethyl trimethylammonium) or permanent anionic charged moieties (3-sulfopropyl methacrylate potassium salt). The resulting charged polymers can be conjugated further with various amounts of cell adhesive RGD motifs (0, 25, 75, and 98%) to study the influences of RGD motifs on breast cancer (MCF-7) spheroid formation. Formation, stability, and mechanical properties of hydrogels were tested with, and without, RGD to evaluate the cellular response to material parameters in a 3D environment. The hydrogels can be degraded in the presence of salts at room temperature by breaking the interaction of oppositely charged polymer chains. MCF-7 cells could be released with high viability through brief exposure to NaCl solution. Flow cytometry characterization demonstrated that embedded MCF-7 cells proliferate better in a softer (60 Pa) 3D hydrogel environment compared to those that are stiffer (1160 Pa). As the stiffness increases, the RGD motif plays a role in promoting cell proliferation in the stiffer hydrogel. Flow cytometry characterization demonstrated that embedded MCF-7 cells proliferate better in a softer (60 Pa) 3D hydrogel environment compared to those that are stiffer (1160 Pa). As the stiffness increases, the RGD motif plays a role in promoting cell proliferation in the stiffer hydrogel. Additionally, cell viability was not impacted by the tested hydrogel stiffness range between 60 to 1160 Pa. Taken together, this PEG-based tuneable hydrogel system shows great promise as a 3D ECM mimic of cancer extracellular environments with controllable biophysical and biochemical properties. The ease of gelation and dissolution through salt concentration provides a way to quickly harvest cells for further analysis at any given time of interest without compromising cell viability.
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Affiliation(s)
- Panthipa Suwannakot
- School of Chemistry, UNSW, Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
| | - Stephanie Nemec
- School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia
| | - Newton Gil Peres
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, UNSW, Sydney, New South Wales 2052, Australia
| | - Eric Y Du
- School of Chemistry, UNSW, Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
| | - Kristopher A Kilian
- School of Chemistry, UNSW, Sydney, New South Wales 2052, Australia
- School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
| | - Katharina Gaus
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, UNSW, Sydney, New South Wales 2052, Australia
| | - Maria Kavallaris
- Children's Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
| | - J Justin Gooding
- School of Chemistry, UNSW, Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
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3
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LeValley PJ, Parsons AL, Sutherland BP, Kiick KL, Oakey JS, Kloxin AM. Microgels Formed by Spontaneous Click Chemistries Utilizing Microfluidic Flow Focusing for Cargo Release in Response to Endogenous or Exogenous Stimuli. Pharmaceutics 2022; 14:1062. [PMID: 35631649 PMCID: PMC9145542 DOI: 10.3390/pharmaceutics14051062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/04/2022] [Accepted: 05/09/2022] [Indexed: 02/05/2023] Open
Abstract
Protein therapeutics have become increasingly popular for the treatment of a variety of diseases owing to their specificity to targets of interest. However, challenges associated with them have limited their use for a range of ailments, including the limited options available for local controlled delivery. To address this challenge, degradable hydrogel microparticles, or microgels, loaded with model biocargoes were created with tunable release profiles or triggered burst release using chemistries responsive to endogenous or exogeneous stimuli, respectively. Specifically, microfluidic flow-focusing was utilized to form homogenous microgels with different spontaneous click chemistries that afforded degradation either in response to redox environments for sustained cargo release or light for on-demand cargo release. The resulting microgels were an appropriate size to remain localized within tissues upon injection and were easily passed through a needle relevant for injection, providing means for localized delivery. Release of a model biopolymer was observed over the course of several weeks for redox-responsive formulations or triggered for immediate release from the light-responsive formulation. Overall, we demonstrate the ability of microgels to be formulated with different materials chemistries to achieve various therapeutic release modalities, providing new tools for creation of more complex protein release profiles to improve therapeutic regimens.
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Affiliation(s)
- Paige J. LeValley
- Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA; (P.J.L.); (B.P.S.)
| | - Amanda L. Parsons
- Chemical Engineering, University of Wyoming, Laramie, WY 82071, USA;
| | - Bryan P. Sutherland
- Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA; (P.J.L.); (B.P.S.)
| | - Kristi L. Kiick
- Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA;
- Biomedical Engineering, University of Delaware, Newark, DE 19716, USA
| | - John S. Oakey
- Chemical Engineering, University of Wyoming, Laramie, WY 82071, USA;
| | - April M. Kloxin
- Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA; (P.J.L.); (B.P.S.)
- Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA;
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4
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Kazybayeva DS, Irmukhametova GS, Khutoryanskiy VV. Thiol-Ene “Click Reactions” as a Promising Approach to Polymer Materials. POLYMER SCIENCE SERIES B 2022. [DOI: 10.1134/s1560090422010055] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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5
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OʼShea TM, Wollenberg AL, Kim JH, Ao Y, Deming TJ, Sofroniew MV. Foreign body responses in mouse central nervous system mimic natural wound responses and alter biomaterial functions. Nat Commun 2020; 11:6203. [PMID: 33277474 PMCID: PMC7718896 DOI: 10.1038/s41467-020-19906-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 10/22/2020] [Indexed: 01/30/2023] Open
Abstract
Biomaterials hold promise for therapeutic applications in the central nervous system (CNS). Little is known about molecular factors that determine CNS foreign body responses (FBRs) in vivo, or about how such responses influence biomaterial function. Here, we probed these factors in mice using a platform of injectable hydrogels readily modified to present interfaces with different physiochemical properties to host cells. We found that biomaterial FBRs mimic specialized multicellular CNS wound responses not present in peripheral tissues, which serve to isolate damaged neural tissue and restore barrier functions. We show that the nature and intensity of CNS FBRs are determined by definable properties that significantly influence hydrogel functions, including resorption and molecular delivery when injected into healthy brain or stroke injuries. Cationic interfaces elicit stromal cell infiltration, peripherally derived inflammation, neural damage and amyloid production. Nonionic and anionic formulations show minimal levels of these responses, which contributes to superior bioactive molecular delivery. Our results identify specific molecular mechanisms that drive FBRs in the CNS and have important implications for developing effective biomaterials for CNS applications.
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Affiliation(s)
- Timothy M OʼShea
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095-1763, USA
| | - Alexander L Wollenberg
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, 90095-1600, USA
| | - Jae H Kim
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095-1763, USA
| | - Yan Ao
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095-1763, USA
| | - Timothy J Deming
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, 90095-1600, USA
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA, 90095-1600, USA
| | - Michael V Sofroniew
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095-1763, USA.
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6
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Marco-Dufort B, Willi J, Vielba-Gomez F, Gatti F, Tibbitt MW. Environment Controls Biomolecule Release from Dynamic Covalent Hydrogels. Biomacromolecules 2020; 22:146-157. [PMID: 32813504 PMCID: PMC7805009 DOI: 10.1021/acs.biomac.0c00895] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Moldable hydrogels composed of dynamic
covalent bonds are attractive
biomaterials for controlled release, as the dynamic exchange of bonds
in these networks enables minimally invasive application via injection.
Despite the growing interest in the biomedical application of dynamic
covalent hydrogels, there is a lack of fundamental understanding as
to how the network design and local environment control the release
of biomolecules from these materials. In this work, we fabricated
boronic-ester-based dynamic covalent hydrogels for the encapsulation
and in vitro release of a model biologic (β-galactosidase).
We systematically investigated the role of network properties and
of the external environment (temperature and presence of competitive
binders) on release from these dynamic covalent hydrogels. We observed
that surface erosion (and associated mass loss) governed biomolecule
release. In addition, we developed a statistical model of surface
erosion based on the binding equilibria in a boundary layer that described
the rates of release. In total, our results will guide the design
of dynamic covalent hydrogels as biomaterials for drug delivery applications.
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Affiliation(s)
- Bruno Marco-Dufort
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Jack Willi
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Felipe Vielba-Gomez
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Francesco Gatti
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Mark W Tibbitt
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
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Wilson RL, Connell JP, Grande-Allen KJ. Monitoring Oxygen Levels within Large, Tissue-Engineered Constructs Using Porphyin-Hydrogel Microparticles. ACS Biomater Sci Eng 2019; 5:4522-4530. [PMID: 33438417 DOI: 10.1021/acsbiomaterials.9b00257] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A major barrier to the creation of engineered organs is the limited diffusion of oxygen through biological tissues. Advances in biofabrication bring us increasingly closer to complex vascular networks capable of supplying oxygen to large cellularized scaffolds. However, technologies for monitoring oxygen levels in engineered tissues do not accommodate imaging depths of more than a few dozen micrometers. Here, we report the creation of fluorescent porphyrin-hydrogel microparticles that can be used at depths of 2 mm into artificial tissues. By combining an oxygen-responsive porphyrin dye with a reference dye, the microparticles generate a ratiometric signal that is photostable, unaffected by attenuation from biological material, and responsive to physiological change in oxygen concentration. These microparticles can measure long-distance oxygen gradients within 3D, cellularized constructs and accurately report cellular oxygen consumption rates. Furthermore, they are compatible with a number of hydrogel polymerization chemistries and cell types, including primary human cells. We believe this technology will significantly advance efforts to visualize oxygen gradients in cellularized constructs and inform efforts to tissue engineer solid organs.
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Affiliation(s)
- Reid L Wilson
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States.,Medical Scientist Training Program, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, United States
| | - Jennifer P Connell
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States
| | - K Jane Grande-Allen
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States
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8
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Gawade PM, Shadish JA, Badeau BA, DeForest CA. Logic-Based Delivery of Site-Specifically Modified Proteins from Environmentally Responsive Hydrogel Biomaterials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1902462. [PMID: 31265196 PMCID: PMC8296976 DOI: 10.1002/adma.201902462] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/26/2019] [Indexed: 05/17/2023]
Abstract
The controlled presentation of proteins from and within materials remains of significant interest for many bioengineering applications. Though "smart" platforms offer control over protein release in response to a single external cue, no strategy has been developed to trigger delivery in response to user-specified combinations of environmental inputs, nor to independently control the release of multiple species from a homogenous material. Here, a modular semisynthetic scheme is introduced to govern the release of site-specifically modified proteins from hydrogels following Boolean logic. A sortase-mediated transpeptidation reaction is used to generate recombinant proteins C-terminally tethered to gels through environmentally sensitive degradable linkers. By varying the connectivity of multiple stimuli-labile moieties within these customizable linkers, YES/OR/AND control of protein release is exhaustively demonstrated in response to one and two-input combinations involving enzyme, reductant, and light. Tethering of multiple proteins each through a different stimuli-sensitive linker permits their independent and sequential release from a common material. It is expected that these methodologies will enable new opportunities in tissue engineering and therapeutic delivery.
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Affiliation(s)
- Prathamesh Milind Gawade
- Department of Chemical Engineering, University of Washington, 3781 Okanogan Lane NE, Seattle, WA, 98195, USA
| | - Jared A Shadish
- Department of Chemical Engineering, University of Washington, 3781 Okanogan Lane NE, Seattle, WA, 98195, USA
| | - Barry A Badeau
- Department of Chemical Engineering, University of Washington, 3781 Okanogan Lane NE, Seattle, WA, 98195, USA
| | - Cole A DeForest
- Department of Chemical Engineering, University of Washington, 3781 Okanogan Lane NE, Seattle, WA, 98195, USA
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA, 98105, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, 850 Republican Street, Seattle, WA, 98109, USA
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9
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Paolini MS, Fenton OS, Bhattacharya C, Andresen JL, Langer R. Polymers for extended-release administration. Biomed Microdevices 2019; 21:45. [DOI: 10.1007/s10544-019-0386-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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10
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Abstract
Light as an external stimulus can be precisely manipulated in terms of irradiation time, site, wavelength, and density. As such, photoresponsive drug/gene delivery systems have been increasingly pursued and utilized for the spatiotemporal control of drug/gene delivery to enhance their therapeutic efficacy and safety. In this review, we summarized the recent research progress on photoresponsive drug/gene delivery, and two major categories of delivery systems were discussed. The first category is the direct responsive systems that experience photoreactions on the vehicle or drug themselves, and different materials as well as chemical structures responsive to UV, visible, and NIR light are summarized. The second category is the indirect responsive systems that require a light-generated mediator signal, such as heat, ROS, hypoxia, and gas molecules, to cascadingly trigger the structural transformation. The future outlook and challenges are also discussed at the end.
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Affiliation(s)
- Yang Zhou
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Huan Ye
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Yongbing Chen
- Department of Cardiothoracic Surgery , The Second Affiliated Hospital of Soochow University , Suzhou 215004 , China
| | - Rongying Zhu
- Department of Cardiothoracic Surgery , The Second Affiliated Hospital of Soochow University , Suzhou 215004 , China
| | - Lichen Yin
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
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11
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Sridhar BV, Janczy JR, Hatlevik Ø, Wolfson G, Anseth KS, Tibbitt MW. Thermal Stabilization of Biologics with Photoresponsive Hydrogels. Biomacromolecules 2018; 19:740-747. [PMID: 29394044 DOI: 10.1021/acs.biomac.7b01507] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Modern medicine, biological research, and clinical diagnostics depend on the reliable supply and storage of complex biomolecules. However, biomolecules are inherently susceptible to thermal stress and the global distribution of value-added biologics, including vaccines, biotherapeutics, and Research Use Only (RUO) proteins, requires an integrated cold chain from point of manufacture to point of use. To mitigate reliance on the cold chain, formulations have been engineered to protect biologics from thermal stress, including materials-based strategies that impart thermal stability via direct encapsulation of the molecule. While direct encapsulation has demonstrated pronounced stabilization of proteins and complex biological fluids, no solution offers thermal stability while enabling facile and on-demand release from the encapsulating material, a critical feature for broad use. Here we show that direct encapsulation within synthetic, photoresponsive hydrogels protected biologics from thermal stress and afforded user-defined release at the point of use. The poly(ethylene glycol) (PEG)-based hydrogel was formed via a bioorthogonal, click reaction in the presence of biologics without impact on biologic activity. Cleavage of the installed photolabile moiety enabled subsequent dissolution of the network with light and release of the encapsulated biologic. Hydrogel encapsulation improved stability for encapsulated enzymes commonly used in molecular biology (β-galactosidase, alkaline phosphatase, and T4 DNA ligase) following thermal stress. β-galactosidase and alkaline phosphatase were stabilized for 4 weeks at temperatures up to 60 °C, and for 60 min at 85 °C for alkaline phosphatase. T4 DNA ligase, which loses activity rapidly at moderately elevated temperatures, was protected during thermal stress of 40 °C for 24 h and 60 °C for 30 min. These data demonstrate a general method to employ reversible polymer networks as robust excipients for thermal stability of complex biologics during storage and shipment that additionally enable on-demand release of active molecules at the point of use.
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Affiliation(s)
- Balaji V Sridhar
- Nanoly Bioscience, Inc. , Denver , Colorado 80231 , United States
| | - John R Janczy
- Nanoly Bioscience, Inc. , Denver , Colorado 80231 , United States
| | - Øyvind Hatlevik
- Nanoly Bioscience, Inc. , Denver , Colorado 80231 , United States
| | - Gabriel Wolfson
- Nanoly Bioscience, Inc. , Denver , Colorado 80231 , United States
| | | | - Mark W Tibbitt
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering , ETH Zürich , 8092 Zürich , Switzerland
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12
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Epithelial-mesenchymal crosstalk influences cellular behavior in a 3D alveolus-fibroblast model system. Biomaterials 2017; 155:124-134. [PMID: 29175081 DOI: 10.1016/j.biomaterials.2017.11.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 11/12/2017] [Indexed: 01/22/2023]
Abstract
Interactions between lung epithelium and interstitial fibroblasts are increasingly recognized as playing a major role in the progression of several lung pathologies, including cancer. Three-dimensional in vitro co-culture systems offer tissue-relevant platforms to study the signaling interplay between diseased and healthy cell types. Such systems provide a controlled environment in which to probe the mechanisms involved in epithelial-mesenchymal crosstalk. To recapitulate the native alveolar tissue architecture, we employed a cyst templating technique to culture alveolar epithelial cells on photodegradable microspheres and subsequently encapsulated the cell-laden spheres within poly (ethylene glycol) (PEG) hydrogels containing dispersed pulmonary fibroblasts. A fibroblast cell line (CCL-210) was co-cultured with either healthy mouse alveolar epithelial primary cells or a cancerous alveolar epithelial cell line (A549) to probe the influence of tumor-stromal interactions on proliferation, migration, and matrix remodeling. In 3D co-culture, cancerous epithelial cells and fibroblasts had higher proliferation rates. When examining fibroblast motility, the fibroblasts migrated faster when co-cultured with cancerous A549 cells. Finally, a fluorescent peptide reporter for matrix metalloproteinase (MMP) activity revealed increased MMP activity when A549s and fibroblasts were co-cultured. When MMP activity was inhibited or when cells were cultured in gels with a non-degradable crosslinker, fibroblast migration was dramatically suppressed, and the increase in cancer cell proliferation in co-culture was abrogated. Together, this evidence supports the idea that there is an exchange between the alveolar epithelium and surrounding fibroblasts during cancer progression that depends on MMP activity and points to potential signaling routes that merit further investigation to determine targets for cancer treatment.
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13
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Huynh CT, Zheng Z, Nguyen MK, McMillan A, Yesilbag Tonga G, Rotello VM, Alsberg E. Cytocompatible Catalyst-Free Photodegradable Hydrogels for Light-Mediated RNA Release To Induce hMSC Osteogenesis. ACS Biomater Sci Eng 2017; 3:2011-2023. [DOI: 10.1021/acsbiomaterials.6b00796] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | - Gulen Yesilbag Tonga
- Department
of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| | - Vincent M. Rotello
- Department
of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
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14
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Foster GA, Headen DM, González-García C, Salmerón-Sánchez M, Shirwan H, García AJ. Protease-degradable microgels for protein delivery for vascularization. Biomaterials 2017; 113:170-175. [PMID: 27816000 PMCID: PMC5121008 DOI: 10.1016/j.biomaterials.2016.10.044] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/19/2016] [Accepted: 10/27/2016] [Indexed: 12/16/2022]
Abstract
Degradable hydrogels to deliver bioactive proteins represent an emerging platform for promoting tissue repair and vascularization in various applications. However, implanting these biomaterials requires invasive surgery, which is associated with complications such as inflammation, scarring, and infection. To address these shortcomings, we applied microfluidics-based polymerization to engineer injectable poly(ethylene glycol) microgels of defined size and crosslinked with a protease degradable peptide to allow for triggered release of proteins. The release rate of proteins covalently tethered within the microgel network was tuned by modifying the ratio of degradable to non-degradable crosslinkers, and the released proteins retained full bioactivity. Microgels injected into the dorsum of mice were maintained in the subcutaneous space and degraded within 2 weeks in response to local proteases. Furthermore, controlled release of VEGF from degradable microgels promoted increased vascularization compared to empty microgels or bolus injection of VEGF. Collectively, this study motivates the use of microgels as a viable method for controlled protein delivery in regenerative medicine applications.
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Affiliation(s)
- Greg A Foster
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Devon M Headen
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Cristina González-García
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; School of Engineering, Division of Biomedical Engineering, University of Glasgow, Glasgow, Scotland, UK
| | - Manuel Salmerón-Sánchez
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; School of Engineering, Division of Biomedical Engineering, University of Glasgow, Glasgow, Scotland, UK
| | - Haval Shirwan
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, USA
| | - Andrés J García
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA.
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15
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Manouras T, Vamvakaki M. Field responsive materials: photo-, electro-, magnetic- and ultrasound-sensitive polymers. Polym Chem 2017. [DOI: 10.1039/c6py01455k] [Citation(s) in RCA: 211] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Recent advances in field-responsive polymers, which have emerged as highly promising materials for numerous applications, are highlighted.
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Affiliation(s)
- Theodore Manouras
- Institute of Electronic Structure and Laser
- Foundation for Research and Technology-Hellas
- Heraklion
- Greece
| | - Maria Vamvakaki
- Institute of Electronic Structure and Laser
- Foundation for Research and Technology-Hellas
- Heraklion
- Greece
- University of Crete
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16
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Kim M, Chung H. Photo-responsive bio-inspired adhesives: facile control of adhesion strength via a photocleavable crosslinker. Polym Chem 2017. [DOI: 10.1039/c7py01535f] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A photo-responsive bio-inspired terpolymer adhesives consisting of a zwitterionic polymer, catechol moiety, and nitrobenzyl crosslinker was synthesized for convenient control of adhesion strength under UV irradiation.
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Affiliation(s)
- Minkyu Kim
- Department of Chemical and Biomedical Engineering
- Florida State University
- Tallahassee
- USA
| | - Hoyong Chung
- Department of Chemical and Biomedical Engineering
- Florida State University
- Tallahassee
- USA
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17
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Abstract
Hydrogel delivery systems can leverage therapeutically beneficial outcomes of drug delivery and have found clinical use. Hydrogels can provide spatial and temporal control over the release of various therapeutic agents, including small-molecule drugs, macromolecular drugs and cells. Owing to their tunable physical properties, controllable degradability and capability to protect labile drugs from degradation, hydrogels serve as a platform in which various physiochemical interactions with the encapsulated drugs control their release. In this Review, we cover multiscale mechanisms underlying the design of hydrogel drug delivery systems, focusing on physical and chemical properties of the hydrogel network and the hydrogel-drug interactions across the network, mesh, and molecular (or atomistic) scales. We discuss how different mechanisms interact and can be integrated to exert fine control in time and space over the drug presentation. We also collect experimental release data from the literature, review clinical translation to date of these systems, and present quantitative comparisons between different systems to provide guidelines for the rational design of hydrogel delivery systems.
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Affiliation(s)
- Jianyu Li
- John A. Paulson School of Engineering and Applied Sciences, and the Wyss Institute for biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
| | - David J Mooney
- John A. Paulson School of Engineering and Applied Sciences, and the Wyss Institute for biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
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18
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Methods for Generating Hydrogel Particles for Protein Delivery. Ann Biomed Eng 2016; 44:1946-58. [PMID: 27160672 DOI: 10.1007/s10439-016-1637-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
Abstract
Proteins represent a major class of therapeutic molecules with vast potential for the treatment of acute and chronic diseases and regenerative medicine applications. Hydrogels have long been investigated for their potential in carrying and delivering proteins. As compared to bulk hydrogels, hydrogel microparticles (microgels) hold promise in improving aspects of delivery owing to their less traumatic route of entry into the body and improved versatility. This review discusses common methods of fabricating microgels, including emulsion polymerization, microfluidic techniques, and lithographic techniques. Microgels synthesized from both natural and synthetic polymers are discussed, as are a series of microgels fashioned from environment-responsive materials.
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19
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Olejniczak J, Nguyen Huu VA, Lux J, Grossman M, He S, Almutairi A. Light-triggered chemical amplification to accelerate degradation and release from polymeric particles. Chem Commun (Camb) 2015; 51:16980-3. [PMID: 26445896 PMCID: PMC4819761 DOI: 10.1039/c5cc06143a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 09/25/2015] [Indexed: 11/23/2022]
Abstract
We describe a means of chemical amplification to accelerate triggered degradation of a polymer and particles composed thereof. We designed a light-degradable copolymer containing carboxylic acids masked by photolabile groups and ketals. Photolysis allows the unmasked acidic groups in the polymer backbone to accelerate ketal hydrolysis even at neutral pH.
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Affiliation(s)
- Jason Olejniczak
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA
| | - Viet Anh Nguyen Huu
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA.
| | - Jacques Lux
- Skaggs School of Pharmacy and Pharmaceutical Science, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA
| | - Madeleine Grossman
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA
| | - Sha He
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA.
| | - Adah Almutairi
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA. and Skaggs School of Pharmacy and Pharmaceutical Science, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA
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20
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de Gracia Lux C, Lux J, Collet G, He S, Chan M, Olejniczak J, Foucault-Collet A, Almutairi A. Short Soluble Coumarin Crosslinkers for Light-Controlled Release of Cells and Proteins from Hydrogels. Biomacromolecules 2015; 16:3286-96. [DOI: 10.1021/acs.biomac.5b00950] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Caroline de Gracia Lux
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
| | - Jacques Lux
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
| | - Guillaume Collet
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
| | - Sha He
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
| | - Minnie Chan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
| | - Jason Olejniczak
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
| | - Alexandra Foucault-Collet
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
| | - Adah Almutairi
- Skaggs School of Pharmacy and Pharmaceutical Sciences, §Department of NanoEngineering, ‡Department of Chemistry
and Biochemistry, and ∥Center for Excellence in Nanomedicine and Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0600, United States
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21
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Kharkar PM, Kiick KL, Kloxin AM. Design of Thiol- and Light-sensitive Degradable Hydrogels using Michael-type Addition Reactions. Polym Chem 2015; 6:5565-5574. [PMID: 26284125 PMCID: PMC4536978 DOI: 10.1039/c5py00750j] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Injectable depots that respond to exogenous and endogenous stimuli present an attractive strategy for tunable, patient-specific drug delivery. Here, the design of injectable and multimodal degradable hydrogels that respond to externally applied light and physiological stimuli, specifically aqueous and reducing microenvironments, is reported. Rapid hydrogel formation was achieved using a thiol-maleimide click reaction between multifunctional poly(ethylene glycol) macromers. Hydrogel degradation kinetics in response to externally applied cytocompatible light, reducing conditions, and hydrolysis were characterized, and degradation of the gel was controlled over multiple time scales from seconds to days. Further, tailored release of an encapsulated model cargo, fluorescent nanobeads, was demonstrated.
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Affiliation(s)
- Prathamesh M. Kharkar
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Kristi L. Kiick
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
- Department of Biomedical Engineering, University of Delaware, Newark, DE 19716, USA
- Delaware Biotechnology Institute, University of Delaware, Newark, DE 19716, USA
| | - April M. Kloxin
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA
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22
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Lewis KJR, Tibbitt MW, Zhao Y, Branchfield K, Sun X, Balasubramaniam V, Anseth KS. In vitro model alveoli from photodegradable microsphere templates. Biomater Sci 2015; 3:821-32. [PMID: 26221842 PMCID: PMC4871129 DOI: 10.1039/c5bm00034c] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Recreating the 3D cyst-like architecture of the alveolar epithelium in vitro has been challenging to achieve in a controlled fashion with primary lung epithelial cells. Here, we demonstrate model alveoli formed within a tunable synthetic biomaterial platform using photodegradable microspheres as templates to create physiologically relevant, cyst structures. Poly(ethylene glycol) (PEG)-based hydrogels were polymerized in suspension to form microspheres on the order of 120 μm in diameter. The gel chemistry was designed to allow erosion of the microspheres with cytocompatible light doses (≤15 min exposure to 10 mW cm(-2) of 365 nm light) via cleavage of a photolabile nitrobenzyl ether crosslinker. Epithelial cells were incubated with intact microspheres, modified with adhesive peptide sequences to facilitate cellular attachment to and proliferation on the surface. A tumor-derived alveolar epithelial cell line, A549, completely covered the microspheres after only 24 hours, whereas primary mouse alveolar epithelial type II (ATII) cells took ∼3 days. The cell-laden microsphere structures were embedded within a second hydrogel formulation at user defined densities; the microsphere templates were subsequently removed with light to render hollow epithelial cysts that were cultured for an additional 6 days. The resulting primary cysts stained positive for cell-cell junction proteins (β-catenin and ZO-1), indicating the formation of a functional epithelial layer. Typically, primary ATII cells differentiated in culture to the alveolar epithelial type I (ATI) phenotype; however, each cyst contained ∼1-5 cells that stained positive for an ATII marker (surfactant protein C), which is consistent with ATII cell numbers in native mouse alveoli. This biomaterial-templated alveoli culture system should be useful for future experiments to study lung development and disease progression, and is ideally suited for co-culture experiments where pulmonary fibroblasts or endothelial cells could be presented in the hydrogel surrounding the epithelial cysts.
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Affiliation(s)
- Katherine J R Lewis
- Department of Chemical and Biological Engineering, the BioFrontiers Institute, and the Howard Hughes Medical Institute, University of Colorado at Boulder, 3415 Colorado Ave, 596 UCB, Boulder, CO 80303, USA.
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23
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Jiang Y, Chen J, Deng C, Suuronen EJ, Zhong Z. Click hydrogels, microgels and nanogels: emerging platforms for drug delivery and tissue engineering. Biomaterials 2014; 35:4969-85. [PMID: 24674460 DOI: 10.1016/j.biomaterials.2014.03.001] [Citation(s) in RCA: 486] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 03/03/2014] [Indexed: 02/06/2023]
Abstract
Hydrogels, microgels and nanogels have emerged as versatile and viable platforms for sustained protein release, targeted drug delivery, and tissue engineering due to excellent biocompatibility, a microporous structure with tunable porosity and pore size, and dimensions spanning from human organs, cells to viruses. In the past decade, remarkable advances in hydrogels, microgels and nanogels have been achieved with click chemistry. It is a most promising strategy to prepare gels with varying dimensions owing to its high reactivity, superb selectivity, and mild reaction conditions. In particular, the recent development of copper-free click chemistry such as strain-promoted azide-alkyne cycloaddition, radical mediated thiol-ene chemistry, Diels-Alder reaction, tetrazole-alkene photo-click chemistry, and oxime reaction renders it possible to form hydrogels, microgels and nanogels without the use of potentially toxic catalysts or immunogenic enzymes that are commonly required. Notably, unlike other chemical approaches, click chemistry owing to its unique bioorthogonal feature does not interfere with encapsulated bioactives such as living cells, proteins and drugs and furthermore allows versatile preparation of micropatterned biomimetic hydrogels, functional microgels and nanogels. In this review, recent exciting developments in click hydrogels, microgels and nanogels, as well as their biomedical applications such as controlled protein and drug release, tissue engineering, and regenerative medicine are presented and discussed.
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Affiliation(s)
- Yanjiao Jiang
- Biomedical Polymers Laboratory, and Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Jing Chen
- Biomedical Polymers Laboratory, and Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Chao Deng
- Biomedical Polymers Laboratory, and Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China.
| | - Erik J Suuronen
- Division of Cardiac Surgery, University of Ottawa Heart Institute, Ottawa K1Y 4W7, Canada
| | - Zhiyuan Zhong
- Biomedical Polymers Laboratory, and Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China.
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24
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Fraser AK, Ki CS, Lin CC. PEG-Based Microgels Formed by Visible-Light-Mediated Thiol-Ene Photo-Click Reactions. MACROMOL CHEM PHYS 2014. [DOI: 10.1002/macp.201300731] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Andrew K. Fraser
- 723 W. Michigan St. SL220K, Department of Biomedical Engineering; Purdue School of Engineering and Technology; Indiana University-Purdue University Indianapolis; Indianapolis IN 46202 USA
| | - Chang Seok Ki
- 723 W. Michigan St. SL220K, Department of Biomedical Engineering; Purdue School of Engineering and Technology; Indiana University-Purdue University Indianapolis; Indianapolis IN 46202 USA
| | - Chien-Chi Lin
- 723 W. Michigan St. SL220K, Department of Biomedical Engineering; Purdue School of Engineering and Technology; Indiana University-Purdue University Indianapolis; Indianapolis IN 46202 USA
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25
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Pinkerton NM, Zhang SW, Youngblood RL, Gao D, Li S, Benson BR, Anthony J, Stone HA, Sinko PJ, Prud’homme RK. Gelation chemistries for the encapsulation of nanoparticles in composite gel microparticles for lung imaging and drug delivery. Biomacromolecules 2014; 15:252-61. [PMID: 24410445 PMCID: PMC3981107 DOI: 10.1021/bm4015232] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The formation of 10-40 μm composite gel microparticles (CGMPs) comprised of ∼100 nm drug containing nanoparticles (NPs) in a poly(ethylene glycol) (PEG) gel matrix is described. The CGMP particles enable targeting to the lung by filtration from the venous circulation. UV radical polymerization and Michael addition polymerization reactions are compared as approaches to form the PEG matrix. A fluorescent dye in the solid core of the NP was used to investigate the effect of reaction chemistry on the integrity of encapsulated species. When formed via UV radical polymerization, the fluorescence signal from the NPs indicated degradation of the encapsulated species by radical attack. The degradation decreased fluorescence by 90% over 15 min of UV exposure. When formed via Michael addition polymerization, the fluorescence was maintained. Emulsion processing using controlled shear stress enabled control of droplet size with narrow polydispersity. To allow for emulsion processing, the gelation rate was delayed by adjusting the solution pH. At a pH = 5.4, the gelation occurred at 3.5 h. The modulus of the gels was tuned over the range of 5 to 50 kPa by changing the polymer concentration between 20 and 70 vol %. NP aggregation during polymerization, driven by depletion forces, was controlled by the reaction kinetics. The ester bonds in the gel network enabled CGMP degradation. The gel modulus decreased by 50% over 27 days, followed by complete gel degradation after 55 days. This permits ultimate clearance of the CGMPs from the lungs. The demonstration of uniform delivery of 15.8 ± 2.6 μm CGMPs to the lungs of mice, with no deposition in other organs, is shown, and indicates the ability to concentrate therapeutics in the lung while avoiding off-target toxic exposure.
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Affiliation(s)
- Nathalie M. Pinkerton
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Stacey W. Zhang
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Richard L. Youngblood
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Dayuan Gao
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, United States
| | - Shike Li
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, United States
| | - Bryan R. Benson
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - John Anthony
- Department of Chemistry, University of Kentucky, Lexington, KY 40506, United States
| | - Howard A. Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Patrick J. Sinko
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, United States
| | - Robert K. Prud’homme
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
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26
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Kharkar PM, Kloxin AM, Kiick KL. Dually degradable click hydrogels for controlled degradation and protein release. J Mater Chem B 2014; 2:5511-5521. [PMID: 25908977 PMCID: PMC4405130 DOI: 10.1039/c4tb00496e] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Crosslinks that can undergo click bond cleavage and ester hydrolysis were incorporated to design glutathione-sensitive, dually degradable hydrogels for degradation-mediated, controlled release of cargo molecules.
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Affiliation(s)
- Prathamesh M. Kharkar
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - April M. Kloxin
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA
| | - Kristi L. Kiick
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
- Biomedical Engineering, University of Delaware, Newark, DE 19716, USA
- Delaware Biotechnology Institute, University of Delaware, Newark, DE 19716, USA
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27
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Kharkar PM, Kiick KL, Kloxin AM. Designing degradable hydrogels for orthogonal control of cell microenvironments. Chem Soc Rev 2013; 42:7335-72. [PMID: 23609001 PMCID: PMC3762890 DOI: 10.1039/c3cs60040h] [Citation(s) in RCA: 470] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Indexed: 12/12/2022]
Abstract
Degradable and cell-compatible hydrogels can be designed to mimic the physical and biochemical characteristics of native extracellular matrices and provide tunability of degradation rates and related properties under physiological conditions. Hence, such hydrogels are finding widespread application in many bioengineering fields, including controlled bioactive molecule delivery, cell encapsulation for controlled three-dimensional culture, and tissue engineering. Cellular processes, such as adhesion, proliferation, spreading, migration, and differentiation, can be controlled within degradable, cell-compatible hydrogels with temporal tuning of biochemical or biophysical cues, such as growth factor presentation or hydrogel stiffness. However, thoughtful selection of hydrogel base materials, formation chemistries, and degradable moieties is necessary to achieve the appropriate level of property control and desired cellular response. In this review, hydrogel design considerations and materials for hydrogel preparation, ranging from natural polymers to synthetic polymers, are overviewed. Recent advances in chemical and physical methods to crosslink hydrogels are highlighted, as well as recent developments in controlling hydrogel degradation rates and modes of degradation. Special attention is given to spatial or temporal presentation of various biochemical and biophysical cues to modulate cell response in static (i.e., non-degradable) or dynamic (i.e., degradable) microenvironments. This review provides insight into the design of new cell-compatible, degradable hydrogels to understand and modulate cellular processes for various biomedical applications.
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Affiliation(s)
- Prathamesh M. Kharkar
- Department of Materials Science and Engineering , University of Delaware , Newark , DE 19716 , USA . ;
| | - Kristi L. Kiick
- Department of Materials Science and Engineering , University of Delaware , Newark , DE 19716 , USA . ;
- Biomedical Engineering , University of Delaware , Newark , DE 19716 , USA
- Delaware Biotechnology Institute , University of Delaware , Newark , DE 19716 , USA
| | - April M. Kloxin
- Department of Materials Science and Engineering , University of Delaware , Newark , DE 19716 , USA . ;
- Department of Chemical and Biomolecular Engineering , University of Delaware , Newark , DE 19716 , USA
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28
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Rehmann MS, Garibian AC, Kloxin AM. Hydrolytically degradable thiol-ene hydrogels for protein release. ACTA ACUST UNITED AC 2013; 329:58-65. [PMID: 25309103 DOI: 10.1002/masy.201200133] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A new degradable PEG-diester-dinorbornene/PEG-triester-trithiol hydrogel was evaluated for protein release. The hydrogel polymerized rapidly with seconds of UV irradiation and subsequently hydrolytically degraded in aqueous buffer over the course of approximately 3 weeks. Further, the hydrogel enabled the encapsulation and release of a model protein, bovine serum albumin (BSA), over 7 days with ~ 90% released at 48 h. This study serves as a proof-of-concept for the creation of hydrolytically degradable, PEG-ester-thiol-based hydrogels by a photoinitiated step growth mechanism for protein release. With this approach, degradation and release rates could be tuned by varying the monomer molecular weight and functionality in future studies.
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Affiliation(s)
- Matthew S Rehmann
- Department of Chemical & Biomolecular Engineering, University of Delaware, 150 Academy Street, Colburn Laboratory, Newark, Delaware, U.S.A. 19716
| | - Andrew C Garibian
- Department of Chemical & Biomolecular Engineering, University of Delaware, 150 Academy Street, Colburn Laboratory, Newark, Delaware, U.S.A. 19716
| | - April M Kloxin
- Department of Chemical & Biomolecular Engineering, University of Delaware, 150 Academy Street, Colburn Laboratory, Newark, Delaware, U.S.A. 19716 ; Department of Materials Science & Engineering, University of Delaware, Newark, Delaware, U.S.A. 19716
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29
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Alge DL, Anseth KS. Thiol‐X Reactions in Tissue Engineering. THIOL‐X CHEMISTRIES IN POLYMER AND MATERIALS SCIENCE 2013. [DOI: 10.1039/9781849736961-00165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Thiol‐based click reactions have played a key role in the synthesis of biomaterial scaffolds for regenerative medicine applications. Of particular importance has been their use in creating cell‐laden hydrogel matrices for both fundamental and translational applications. Thiol‐X reactions are often exploited in biological applications as they allow for the facile incorporation of biofunctional components, which has led to many key advancements for the field of tissue engineering. In this chapter, we summarize the important considerations for cytocompatible macromolecular monomer design and subsequent cellular encapsulation in hydrogel formulations. Briefly, we review the main thiol‐X reactions that have been used to synthesize hydrogel cell scaffold systems; provide a generalized protocol for the preparation of cell‐laden hydrogels; present highlights that demonstrate specific advantages of thiol‐X reactions and advances in their application in regenerative medicine research; and conclude with a prospectus on future directions for the field in using thiol‐X chemistries to engineer more advanced hydrogel materials.
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Affiliation(s)
- Daniel L. Alge
- Department of Chemical and Biological Engineering University of Colorado, Boulder, CO 80303‐1904 USA
| | - Kristi S. Anseth
- Department of Chemical and Biological Engineering University of Colorado, Boulder, CO 80303‐1904 USA
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30
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Tibbitt MW, Kloxin AM, Anseth KS. Modeling Controlled Photodegradation in Optically Thick Hydrogels. JOURNAL OF POLYMER SCIENCE. PART A, POLYMER CHEMISTRY 2013; 51:1899-1911. [PMID: 24496479 PMCID: PMC3785226 DOI: 10.1002/pola.26574] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
There is a growing interest in developing dynamically responsive hydrogels whose material properties are modulated by environmental cues, including with light. These photoresponsive hydrogels afford spatiotemporal control of material properties through an array of photoaddition and photodegradation reactions. For photoresponsive hydrogels to be utilized most effectively in a broad range of applications, the photoreaction behavior should be well understood, enabling the design of dynamic materials with uniform or anisostropic material properties. Here, a general statistical-kinetic model has been developed to describe controlled photodegradation in hydrogel polymer networks containing photolabile crosslinks. The heterogeneous reaction rates that necessarily accompany photochemical reactions were described by solving a system of partial differential equations that quantify the photoreaction kinetics in the material. The kinetics were coupled with statistical descriptions of network structure in chain polymerized hydrogels to model material property changes and mass loss that occur during the photodegradation process. Finally, the physical relevance of the model was demonstrated by comparing model predictions with experimental data of mass loss and material property changes in photodegradable, PEG-based hydrogels.
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Affiliation(s)
- Mark W. Tibbitt
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303
| | - April M. Kloxin
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303
- Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, Colorado 80303
| | - Kristi S. Anseth
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303
- Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, Colorado 80303
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31
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Abstract
Photodegradable hydrogels have emerged as a powerful material platform for studying and directing cell behaviors, as well as for delivering drugs. The premise of this technique is to use a cytocompatible light source to cleave linkers within a hydrogel, thus causing reduction of matrix stiffness or liberation of matrix-tethered biomolecules in a spatial-temporally controlled manner. The most commonly used photodegradable units are molecules containing nitrobenzyl moieties that absorb light in the ultraviolet (UV) to lower visible wavelengths (~280 to 450 nm). Because photodegradable linkers and hydrogels reported in the literature thus far are all sensitive to UV light, highly efficient UV-mediated photopolymerizations are less likely to be used as the method to prepare these hydrogels. As a result, currently available photodegradable hydrogels are formed by redox-mediated radical polymerizations, emulsion polymerizations, Michael-type addition reactions, or orthogonal click chemistries. Here, we report the first photodegradable poly(ethylene glycol)-based hydrogel system prepared by step-growth photopolymerization. The model photolabile peptide cross-linkers, synthesized by conventional solid phase peptide synthesis, contained terminal cysteines for step-growth thiol-ene photo-click reactions and a UV-sensitive 2-nitrophenylalanine residue in the peptide backbone for photo-cleavage. Photolysis of this peptide was achieved through adjusting UV light exposure time and intensity. Photopolymerization of photodegradable hydrogels containing photolabile peptide cross-linkers was made possible via a highly efficient visible light-mediated thiol-ene photo-click reaction using a non-cleavage type photoinitiator eosin-Y. Rapid gelation was confirmed by in situ photo-rheometry. Flood UV irradiation at controlled wavelength and intensity was used to demonstrate the photodegradability of these photopolymerized hydrogels.
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Tibbitt MW, Kloxin AM, Sawicki L, Anseth KS. Mechanical Properties and Degradation of Chain and Step Polymerized Photodegradable Hydrogels. Macromolecules 2013; 46. [PMID: 24496435 PMCID: PMC3652617 DOI: 10.1021/ma302522x] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
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The relationship between polymeric
hydrogel microstructure and
macroscopic properties is of specific interest to the materials science
and polymer science communities for the rational design of materials
for targeted applications. Specifically, research has focused on elucidating
the role of network formation and connectivity on mechanical integrity
and degradation behavior. Here, we compared the mechanical properties
of chain- and step-polymerized, photodegradable hydrogels. Increased
ductility, tensile toughness, and shear strain to yield were observed
in step-polymerized hydrogels, as compared to the chain-polymerized
gels, indicating that increased homogeneity and network cooperativity
in the gel backbone improves mechanical integrity. Furthermore, the
ability to degrade the hydrogels in a controlled fashion with light
was exploited to explore how hydrogel microstructure influences photodegradation
and erosion. Here, the decreased network connectivity at the junction
points in the step-polymerized gels resulted in more rapid erosion.
Finally, a relationship between the reverse gelation threshold and
erosion rate was developed for the general class of photodegradable
hydrogels. In all, these studies further elucidate the relationship
between hydrogel formation and microarchitecture with macroscale behavior
to facilitate the future design of polymer networks and degradable
hydrogels, as well as photoresponsive materials such as cell culture
templates, drug delivery vehicles, responsive coatings, and anisotropic
materials.
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Affiliation(s)
- Mark W Tibbitt
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303 ; BioFrontiers Institute, University of Colorado Boulder, Boulder, Colorado 80303
| | - April M Kloxin
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303 ; Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, Colorado 80303
| | - Lisa Sawicki
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303
| | - Kristi S Anseth
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303 ; Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, Colorado 80303 ; BioFrontiers Institute, University of Colorado Boulder, Boulder, Colorado 80303
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Shenoy R, Tibbitt MW, Anseth K, Bowman CN. Formation of Core-Shell Particles by Interfacial Radical Polymerization Initiated by a Glucose Oxidase-Mediated Redox System. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2013; 25:761-767. [PMID: 23503321 PMCID: PMC3597198 DOI: 10.1021/cm303913f] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/10/2013] [Indexed: 05/13/2023]
Abstract
A unique design paradigm to form core-shell particles based on interfacial radical polymerization is described. The interfacial initiation system is comprised of an enzymatic reaction between glucose and glucose oxidase (GOx) to generate hydrogen peroxide, which, in the presence of iron (Fe2+), generates hydroxyl radicals that initiate polymerization. Shell formation on prefabricated polymeric cores is achieved by localizing the initiation reaction to the interface of the core and a surrounding aqueous monomer formulation into which it is immersed. The interfacially confined initiation reaction is accomplished by incorporating one or more of the initiating species in the particle core and the remainder of the complementary initiating components in the surrounding media such that interactions and the resulting initiation reaction occur at the interface. This work is focused on engineering the reaction behavior and mass transport processes to promote interfacially confined polymerization, controlling the rate of shell formation, and manipulating the structure of the core-shell particle. Specifically, incorporating GOx in the precursor solution used to fabricate cores ranging from 100 to 200 μm, and the remainder of the complementary initiating components and monomer in the bulk solution prior to interfacial polymerization yielded shells whose average thickness was 20 μm after 4 min of immersion and at a bulk iron concentration of 12.5 mM. When the locations of glucose and GOx are interchanged, the average thickness of the shell was 15 or 100 μm for bulk iron concentrations of 45 and 12.5 mM, respectively. The initial locations of glucose and GOx also determine the degree of interpenetration of the core and the shell. Specifically, for a bulk iron concentration of 45 mM, the thickness of the interpenetrating layer averaged 12 μm when GOx was initially within the core, whereas no interpenetrating layer was observed when glucose was incorporated in the core. The polymeric shell formed by this technique is also demonstrated to be self-supporting following core degradation. This behavior is accomplished by fabricating the particle core hydrogel from monomers possessing degradable groups that can be irreversibly cleaved by light exposure following shell formation. When the coated particle was exposed to light, the shell remained intact while the core degraded as evidenced by a dramatic change in diffusion coefficient of fluorescent beads immobilized within the core.
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Affiliation(s)
- Raveesh Shenoy
- Department of Chemical and Biological
Engineering, University of Colorado, UCB
596, Boulder, Colorado 80309, United States
| | - Mark W. Tibbitt
- Department of Chemical and Biological
Engineering, University of Colorado, UCB
596, Boulder, Colorado 80309, United States
| | - Kristi
S. Anseth
- Department of Chemical and Biological
Engineering, Howard Hughes Medical Institute, University
of Colorado, UCB 596, Boulder, Colorado 80309, United
States
| | - Christopher N. Bowman
- Department of Chemical and Biological
Engineering, University of Colorado, UCB
596, Boulder, Colorado 80309, United States
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34
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Kirschner CM, Anseth KS. In situ control of cell substrate microtopographies using photolabile hydrogels. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:578-84. [PMID: 23074095 PMCID: PMC3574214 DOI: 10.1002/smll.201201841] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Indexed: 05/26/2023]
Abstract
Substratum topography can play a significant role in regulating cellular function and fate. To study cellular responses to biophysical cues, researchers have developed dynamic methods for controlling cell morphology; however, many of these platforms are limited to one transition between two predefined substratum topographies. To afford the user additional control over the presentation of microtopographic cues to cell populations, a photolabile, PEG-based hydrogel system is presented in which precisely engineered topographic cues can be formed in situ by controlled erosion. Here, the ability to produce precisely engineered static microtopographies in the hydrogel surface is first established. Human mesenchymal stem cell (hMSC) response to topographies with features of subcellular dimensions (~5 to 40 μm) and with various aspect ratios increasing from 1:1 to infinity (e.g., channels) are quantified, and the dynamic nature of the culture system is demonstrated by sequentially presenting a series of topographies through in situ modifications and quantifying reversible changes in cell morphology in response to substratum topographies altered in real time.
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Affiliation(s)
- Chelsea M Kirschner
- Department of Chemical and Biological EngineeringUniversity of Colorado, 596 UCB, Boulder, Colorado, 80303-1904, USA
- The Biofrontiers Institute, University of Colorado596 UCB, Boulder, Colorado, 80303-1904, USA
| | - Kristi S Anseth
- The Biofrontiers Institute, University of Colorado596 UCB, Boulder, Colorado, 80303-1904, USA
- The Howard Hughes Medical Institute, University of Colorado596 UCB, Boulder, Colorado, 80303-1904, USA
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Kirschner CM, Anseth KS. Hydrogels in Healthcare: From Static to Dynamic Material Microenvironments. ACTA MATERIALIA 2013; 61:931-944. [PMID: 23929381 PMCID: PMC3735227 DOI: 10.1016/j.actamat.2012.10.037] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Advances in hydrogel design have revolutionized the way biomaterials are applied to address biomedical needs. Hydrogels were introduced in medicine over 50 years ago and have evolved from static, bioinert materials to dynamic, bioactive microenvironments, which can be used to direct specific biological responses such as cellular ingrowth in wound healing or on-demand delivery of therapeutics. Two general classes of mechanisms, those defined by the user and those dictated by the endogenous cells and tissues, can control dynamic hydrogel microenvironments. These highly tunable materials have provided bioengineers and biological scientists with new ways to not only treat patients in the clinic but to study the fundamental cellular responses to engineered microenvironments as well. Here, we provide a brief history of hydrogels in medicine and follow with a discussion of the synthesis and implementation of dynamic hydrogel microenvironments for healthcare-related applications.
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Affiliation(s)
- Chelsea M. Kirschner
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado, USA
| | - Kristi S. Anseth
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado, USA
- Biofrontiers Institute, University of Colorado, Boulder, Colorado, USA
- Howard Hughes Medical Institute, University of Colorado, Boulder, Colorado, USA
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36
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McCall J, Anseth KS. Thiol-ene photopolymerizations provide a facile method to encapsulate proteins and maintain their bioactivity. Biomacromolecules 2012; 13:2410-7. [PMID: 22741550 PMCID: PMC3421966 DOI: 10.1021/bm300671s] [Citation(s) in RCA: 158] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 06/26/2012] [Indexed: 12/11/2022]
Abstract
Photoinitiated polymerization remains a robust method for fabrication of hydrogels, as these reactions allow facile spatial and temporal control of gelation and high compatibility for encapsulation of cells and biologics. The chain-growth reaction of macromolecular monomers, such as acrylated PEG and hyaluronan, is commonly used to form hydrogels, but there is growing interest in step-growth photopolymerizations, such as the thiol-ene "click" reaction, as an alternative. Thiol-ene reactions are not susceptible to oxygen inhibition and rapidly form hydrogels using low initiator concentrations. In this work, we characterize the differences in recovery of bioactive proteins when exposed to similar photoinitiation conditions during thiol-ene versus acrylate polymerizations. Following exposure to chain polymerization of acrylates, lysozyme bioactivity was approximately 50%; after step-growth thiol-ene reaction, lysozyme retained nearly 100% of its prereaction activity. Bioactive protein recovery was enhanced 1000-fold in the presence of a thiol-ene reaction, relative to recovery from solutions containing identical primary radical concentrations, but without the thiol-ene components. When the cytokine TGFβ was encapsulated in PEG hydrogels formed via the thiol-ene reaction, full protein bioactivity was preserved.
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Affiliation(s)
- Joshua
D. McCall
- Department of Chemical
and Biological Engineering and the BioFrontiers
Institute, University of Colorado at Boulder, Boulder, Colorado, 80303, United States
| | - Kristi S. Anseth
- Department of Chemical
and Biological Engineering and the BioFrontiers
Institute, University of Colorado at Boulder, Boulder, Colorado, 80303, United States
- Howard Hughes Medical
Institute, University of Colorado at Boulder, Boulder, Colorado, 80303, United States
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