Development of a Shear-thinning Therapeutic Biomimetic Hydrogel for Minimally-invasive in Situ Cardiac Tissue Engineering

Development of a Shear-thinning Therapeutic Biomimetic Hydrogel for Minimally-invasive in Situ Cardiac Tissue Engineering
Author: Amanda Nicole Steele
Publisher:
Total Pages:
Release: 2019
Genre:
ISBN:

Cardiovascular disease and its multiple sequelae comprise the leading cause of morbidity and mortality worldwide. Though overall mortality following myocardial infarction has improved substantially over the last half century, many patients will ultimately succumb to heart failure despite pharmacologic, revascularization, and reconstructive therapies. The gold standard treatments focus on pharmacologic management and macro-revascularization via percutaneous coronary intervention and/or coronary artery bypass graft. Yet these therapies fail to address the significant and pervasive microvascular malperfusion that occurs after myocardial infarction due to endothelial cell dysfunction and death and micro-occlusions. This microvascular malperfusion ultimately leads to cardiomyocyte injury and death, ventricular remodeling, and progressive functional deterioration. Targeted therapies via cardiovascular tissue engineering approaches offer an adjunct treatment to the gold standard via enhancing myocardial revascularization, repair and regeneration. To date, there has been modest and varied success with such approaches, likely due to limitations in mechanistic understanding and suboptimal delivery techniques. Thus, novel approaches to restore the microvasculature and repair myocardial tissue remain significant unmet needs. The Woo Lab studies endogenous mechanisms of myocardial angiogenesis, develops myocardial regeneration strategies, and translates novel molecular and biomaterial therapeutics for the prevention of heart failure. In this work, we aimed to elucidate and highlight the advantage of novel protein cytokine therapeutics delivered to the myocardium in translatable hydrogels for the treatment of myocardial ischemia. We examined the ability of an engineered dimeric fragment of hepatocyte growth factor (HGFdf) and an engineered variant of stromal cell-derived factor-1 (ESA) to stimulate cardioprotective functions in vitro on cardiac-relevant cell types including cardiomyocytes, endothelial progenitor cells, endothelial cells and fibroblasts. Additionally, we elucidated the advantage of delivering these cytokines in injectable hydrogels, which effectively prolonged their half-lives in vitro and in vivo, ultimately extending the therapeutic window. Harnessing lessons learned utilizing injectable hydrogels in small and large animal models motivated us to develop a novel, clinically translatable shear-thinning hydrogel, capable of being delivered through clinically relevant catheters. Further, due to the composition and structure of the hydrogel, we demonstrated biocompatibility and cell-signaling properties in addition to precise control over drug delivery via distinct cytokine release profiles. Finally, we translated this therapeutic hydrogel to small and large animal models of myocardial infarction, highlighting the clinical feasibility and potential of this hydrogel system to advance the field of cytokine therapy and hydrogels for the treatment of heart failure, potentially generating a significant impact on the treatment of patients afflicted with the most common cause of death worldwide.

Injectable Biomaterials

Injectable Biomaterials
Author: Brent Vernon
Publisher: Elsevier
Total Pages: 425
Release: 2011-01-24
Genre: Medical
ISBN: 0857091379

Novel injectable materials for non-invasive surgical procedures are becoming increasingly popular. An advantage of these materials include easy deliverability into the body, however the suitability of their mechanical properties must also be carefully considered. Injectable biomaterials covers the materials, properties and biomedical applications of injectable materials, as well as novel developments in the technology.Part one focuses on materials and properties, with chapters covering the design of injectable biomaterials as well as their rheological properties and the mechanical properties of injectable polymers and composites. Part two covers the clinical applications of injectable biomaterials, including chapters on drug delivery, tissue engineering and orthopaedic applications as well as injectable materials for gene delivery systems. In part three, existing and developing technologies are discussed. Chapters in this part cover such topics as environmentally responsive biomaterials, injectable nanotechnology, injectable biodegradable materials and biocompatibility. There are also chapters focusing on troubleshooting and potential future applications of injectable biomaterials.With its distinguished editor and international team of contributors, Injectable biomaterials is a standard reference for materials scientists and researchers working in the biomaterials industry, as well as those with an academic interest in the subject. It will also be beneficial to clinicians. Comprehensively examines the materials, properties and biomedical applications of injectable materials, as well as novel developments in the technology Reviews the design of injectable biomaterials as well as their rheological properties and the mechanical properties of injectable polymers and composites Explores clinical applications of injectable biomaterials, including drug delivery, tissue engineering, orthopaedic applications and injectable materials for gene delivery systems

Injectable Hydrogels for Regenerative Engineering

Injectable Hydrogels for Regenerative Engineering
Author: Lakshmi S. Nair
Publisher: World Scientific
Total Pages: 446
Release: 2015-12-28
Genre: Science
ISBN: 178326747X

"Regenerative engineering, with its ability to foster novel therapeutic techniques and strategies, has emerged as the most versatile and innovative technology of the 21st century. The past few years have seen a significant interest in the development of injectable hydrogels as a delivery system to realize the dream of regenerative engineering. The book will explain synthetic approaches towards developing injectable hydrogels, and the clinical implications and applications of injectable hydrogels for engineering various tissues. Injectable Hydrogels for Regenerative Engineering is the first of its kind to bring together the fields of injectable hydrogels and regenerative engineering to give a perspective of the emerging therapeutic strategies for a wide audience."--

Biomimetic Protein Based Elastomers

Biomimetic Protein Based Elastomers
Author: Namita Roy Choudhury
Publisher: Royal Society of Chemistry
Total Pages: 297
Release: 2022-04-20
Genre: Science
ISBN: 1839161027

Elastomeric proteins are ubiquitous in nature, where they have evolved precise structures and properties that are necessary to perform specific biological roles and functions. This book emphasizes the impact of amino acid sequence on modulating protein structure, properties, and function. Examples include conformational ensemble dynamics, environmental responsiveness, self-assembly, physico-mechanical properties, morphology, and properties tailored for biomedical applications. This foundational framework is not only critical to advance scientific understanding and knowledge on elastomeric proteins but also enables the conceptualization, rational design, and development of biosynthetic elastomers and their analogous polypeptides for a variety of applications. Edited and contributed by pioneering researchers in the field, the book provides a timely overview of the materials, along with the synthesis techniques, the unique characteristics of elastomeric proteins, and biomedical and industrial applications. The book will provide a reference for graduate students and researchers interested in designing biomimetic proteins tailored for various functions.

Development of Shear-thinning and Self-healing Hydrogels Through Guest-host Interactions for Biomedical Applications

Development of Shear-thinning and Self-healing Hydrogels Through Guest-host Interactions for Biomedical Applications
Author: Christopher B. Rodell
Publisher:
Total Pages: 622
Release: 2016
Genre:
ISBN:

Both GH and DC hydrogels were further explored in vivo, with application to attenuate the maladaptive left ventricular (LV) remodeling that occurs following myocardial infarction (MI) that can result in heart failure. DC hydrogels reduced stress within the infarct region, prevented early ventricular expansion and thereby ameliorated progressive LV remodeling. Moreover, the preservation of myocardial geometry reduced incidence and severity of ischemic mitral regurgitation — an undesirable and devastating consequence of LV remodeling. Overall, the body of work represents a novel approach to engineer biomaterials with unique properties toward biomedical therapies.

Development and Characterization of Multi-Crosslinking Injectable Hydrogels for Use in Cell and Drug Delivery

Development and Characterization of Multi-Crosslinking Injectable Hydrogels for Use in Cell and Drug Delivery
Author: Jennifer Etter
Publisher:
Total Pages: 272
Release: 2019
Genre: Alginates
ISBN:

Injectable hydrogels are important for use in tissue engineering due to their permeability and biocompatibility. Those that have shear thinning properties allow for minimally-invasive surgical procedures and a way to administer bioactive agents, and therapeutic cells by injection. Currently available injectable hydrogels have a single or dual input/stimulus for crosslinking which limits the range of mechanical properties and often utilize potentially toxic ultraviolet radiation that reduces viability of injected cells. To overcome these shortcomings, a tri-stimuli-responsive alginate-based injectable hydrogel was developed based on: 1) supramolecular complex formation between [beta]-cyclodextrin ([beta]-CD) conjugated alginate and thermo-responsive tri-block Pluronic® copolymers, 2) visible light crosslinking via acrylate conjugation, and 3) ionic crosslinking of the alginate backbone via exposure to calcium chloride. The capabilities of the novel multi-stimuli injectable hydrogel were demonstrated with a custom microfluidic devices (MFDs) to create microspheres encapsulating human mesenchymal stem cell (MSCs). These experiments proved that the new hydrogel was capable of serving as a stimuli responsive material for MSC cell delivery in the therapeutic range of 10-1000 [mu]m in diameter. In order to enhance the drug delivery capabilities of the hydrogel, heparin sodium was conjugated onto the alginate backbone. The affinity of the growth factor, vascular endothelial growth factor (VEGF), to the heparin helped to prevent denaturing of the protein and improved vascularization. This new tri-crosslinking hydrogel with conjugated heparin allows the end-user to control the final physicomechanical and biochemical properties of the hydrogel using different external stimuli. The tri-crosslinking hydrogel is a versatile material that has great promise for a variety of soft tissue repair applications.

Synthesis and Characterization of Tissue-engineered Collagen Hydrogels for the Delivery of Therapeutic Cells

Synthesis and Characterization of Tissue-engineered Collagen Hydrogels for the Delivery of Therapeutic Cells
Author: Kimberly A. McEwan
Publisher:
Total Pages:
Release: 2003
Genre: University of Ottawa theses
ISBN:

The expanding field of tissue engineering provides a new approach to regenerative medicine for common ailments such as cardiovascular disease and type-I diabetes. Biomaterials can be administered as a delivery vehicle to introduce therapeutic cells to sites of damaged or diseased tissue. A specific class of biomaterials, termed hydrogels, is suitable for this application as they can provide a biocompatible, biodegradable scaffold that mimics the physical properties of the native soft tissue. Injectable hydrogels are increasingly being developed for biomedical applications due to their ability to be delivered in a minimally invasive manner. One potential use for such materials is in the delivery of therapeutics such as cells or growth factor-releasing particles. In this study, the first aim was to determine the interactive effects between collagen-based hydrogels and additives (cells and microspheres) for cardiac regeneration. The results demonstrated that the addition of either cells or microspheres to a collagen-based hydrogel decreased its gelation time and increased its viscosity. Increased cross-linker concentrations resulted in lower cell viability. However, this cell loss could be minimized by delivering cells with the cross-linker neutralizing agent, glycine. As a potential application of these materials, the second aim of this study was to develop a hydrogel for use as an ectopic islet transplant site. Specifically, collagen-chitosan hydrogels were synthesized and characterized, with and without laminin, and tested for their ability to support angiogenic and islet cell survival and function. Matrices synthesized with lower chitosan content (20:1 collagen:chitosan) displayed greater cell compatibility for both angiogenic cells and for islets and weaker mechanical properties, while matrices with higher chitosan content (10:1 collagen:chitosan) had the opposite effect. Laminin did not affect the physical properties of the matrices, but did improve angiogenic cell and islet survival and function. Overall the proposed collagen-based hydrogels can be tailored to meet the physical property requirements for cardiac and islet tissue engineering applications and demonstrated promising cell support capabilities.

Hydrogels for Tissue Engineering and Regenerative Medicine

Hydrogels for Tissue Engineering and Regenerative Medicine
Author: J. Miguel Oliveira
Publisher: Academic Press
Total Pages: 851
Release: 2023-09-29
Genre: Science
ISBN: 0128242256

Hydrogels for Tissue Engineering and Regenerative Medicine: From Fundaments to Applications provides the reader with a comprehensive, concise and thoroughly up-to-date resource on the different types of hydrogels in tissue engineering and regenerative medicine. The book is divided into three main sections that describe biological activities and the structural and physicochemical properties of hydrogels, along with a wide range of applications, including their combination with emerging technologies. Written by a diverse range of international academics for professionals, researchers, undergraduate and graduate students, this groundbreaking publication fills a gap in literature needed in the tissue engineering and regenerative medicine field. Reviews the fundamentals and recent advances of hydrogels in tissue engineering and regenerative medicine applications Presents state-of-the-art methodologies for the synthesis and processing of different types of hydrogels Includes contributions by leading experts in engineering, the life sciences, microbiology and clinical medicine