Non-viral DNA delivery from porous hyaluronic acid hydrogels in mice

Biomimetic Hydrogel Containing Copper Sulfide Nanoparticles and Deferoxamine for Photothermal Therapy of Infected Diabetic Wounds

Inducing cell migration from the edges to the center of a wound, promoting angiogenesis, and controlling bacterial infection are very important for diabetic wound healing. Incorporating growth factors and antibiotics into hydrogels for wound dressing is considered a potential strategy to meet these requirements. However, some present drawbacks greatly slow down their development toward application, such as the short half-life and high price of growth factors, low antibiotic efficiency against drug-resistant bacteria, insufficient ability of hydrogels to promote cell migration, etc. Deferoxamine (DFO) can upregulate the expression of HIF-1α, thus stimulating the secretion of angiogenesis-related endogenous growth factors. Copper sulfide (CuS) nanoparticles possess excellent antibacterial performance combined with photothermal therapy (PTT). Herein, DFO and CuS nanoparticles are incorporated into a biomimetic hydrogel, which mimics the structure and function of the extracellular matrix (ECM), abbreviated as DFO/CuS-ECMgel. This biomimetic hydrogel is expected to be able to promote cell adhesion and migration, be degraded by cell-secreted matrix metalloproteinases (MMPs), and then release DFO and CuS nanoparticles at the wound site to exert their therapeutic effects. As a result, the three crucial requirements for diabetic wound healing, "beneficial for cell adhesion and migration, promoting angiogenesis, effectively killing drug-resistant bacteria," can be achieved simultaneously.

Non-viral gene therapy using RNA interference with PDGFR-α mediated epithelial-mesenchymal transformation for proliferative vitreoretinopathy

Fibrotic eye diseases, a series of severe oculopathy, that will destroy normal ocular refractive media and imaging structures. It is characterized by the transformation of the epithelial cells into mesenchyme cells. Proliferative vitreoretinopathy (PVR) is one of these representative diseases. In this investigation, polyethylene glycol grafted branched Polyethyleneimine (PEI-g-PEG) was used as a non-viral gene vector in gene therapy of PVR to achieve anti-fibroblastic effects in vitro and in vivo by interfering with platelet-derived growth factor alpha receptor (PDGFR-α) in the epithelial-mesenchymal transition (EMT) of retinal pigment epithelium (RPE) cells. The plasmid was wrapped by electrostatic conjugation. Physical characterization of the complexes indicated that the gene complexes were successfully prepared. In vitro, cellular experiments showed excellent biocompatibility of PEI-g-PEG, efficient cellular uptake of the gene complexes, and successful expression of the corresponding fragments. Through gene silencing technique, PEI-g-PEG/PDGFR-α shRNA successfully inhibited the process of EMT in vitro. Furthermore, in vivo animal experiments suggested that this method could effectively inhibit the progression of fibroproliferative membranes of PVR. Herein, a feasible and promising clinical idea was provided for developing non-viral gene vectors and preventing fibroblastic eye diseases by RNA interference (RNAi) technology.

VEGF-Encoding, Gene-Activated Collagen-Based Matrices Promote Blood Vessel Formation and Improved Wound Repair

Disruption in vascularization during wound repair can severely impair healing. Proangiogenic growth factor therapies have shown great healing potential; however, controlling growth factor activity and cellular behavior over desired healing time scales remains challenging. In this study, we evaluated collagen-mimetic peptide (CMP) tethers for their capacity to control growth factor gene transfer and growth factor activity using our recently developed gene-activated hyaluronic acid-collagen matrix (GAHCM). GAHCM was comprised of DNA/polyethyleneimine (PEI) polyplexes that were retained on hyaluronic acid (HA)-collagen hydrogels using CMPs. We hypothesized that using CMP-collagen tethers to control vascular endothelial growth factor-A (VEGF-A) gene delivery in fibroblasts would provide a powerful strategy to modulate the proangiogenic behaviors of endothelial cells (ECs) for blood vessel formation, resulting in enhanced wound repair. In co-culture experiments, we observed that CMP-modified GAHCM induced tunable gene delivery in fibroblasts as predicted, and correspondingly, VEGF-A produced by the fibroblasts led to increased growth and persistent migration of ECs for at least 7 days, as compared to non-CMP-modified GAHCM. Moreover, when ECs were exposed to fibroblast-containing VEGF-GAHCM with higher levels of CMP modification (50% CMP-PEI, or 50 CP), high CD31 expression was stimulated, resulting in the formation of an interconnected EC network with a significantly higher network volume and a larger diameter network structure than controls. Application of VEGF-GAHCM with 50 CP in murine splinted excisional wounds facilitated prolonged prohealing and proangiogenic responses resulting in increased blood vessel formation, improved granulation tissue formation, faster re-epithelialization, and overall enhanced repair. These findings suggest the benefits of CMP-collagen tethers as useful tools to control gene transfer and growth factor activity for improved treatment of wounds.

Layer-by-Layer Biomimetic Microgels for 3D Cell Culture and Nonviral Gene Delivery

Localized release of nucleic acid therapeutics is essential for many biomedical applications, including gene therapy, tissue engineering, and medical implant coatings. We applied the substrate-mediated transfection and layer-by-layer (LbL) technique to achieve an efficient local gene delivery. In the experiments presented herein, we embeded lipoplexes containing plasmid DNA encoding for enhanced green fluorescent protein (pEGFP) within polyelectrolyte alginate-based microgels composed of poly(allylamine hydrochloride) (PAH), chondroitin sulfate (CS), and poly-l-lysine (PLL) with diameters between 70 and 90 μm. Droplet-based microfluidics was used as the main process to produce the alginate (ALG)-based microgels with discrete size, shape, and low coefficient of variation. The physicochemical and morphological properties of the polyelectrolyte microgels were characterized via optical microscopy, scanning electron microscopy (SEM), and zeta potential analysis. We found that polyelectrolyte microgels provide low cytotoxicity and cell-material interactions (adhesion, spreading, and proliferation). In addition, the microsystem showed the ability to load lipoplexes and a loading efficiency equal to 83%, and it enabled in vitro surface-based transfection of MCF-7 cells. This approach provides a new suitable route for cell adhesion and local gene delivery.

Nanotechnology-based therapeutic applications: in vitro and in vivo clinical studies for diabetic wound healing

Diabetic wounds often indicate chronic complications that are difficult to treat. Unfortunately, existing conventional treatment modalities often cause unpremeditated side effects, given the need to develop alternative therapeutic phenotypes that are safe or have minimal side effects and risks. Nanotechnology-based platforms, including nanotherapeutics, nanoparticles (NPs), nanofibers, nanohydrogels, and nanoscaffolds, have garnered attention for their groundbreaking potential to decipher the biological environment and offer personalized treatment methods for wound healing. These nanotechnology-based platforms can successfully overcome the impediments posed by drug toxicity, existing treatment modalities, and the physiology and complexity of the wound sites. Furthermore, studies have shown that they play an essential role in influencing angiogenesis, collagen production, and extracellular matrix (ECM) synthesis, which are integral in skin repair mechanisms. In this review, we emphasized the importance of various nanotechnology-based platforms for healing diabetic wounds and report on the innovative preclinical and clinical outcomes of different nanotechnology-based platforms. This review also outlined the limitations of existing conventional treatment modalities and summarized the physiology of acute and chronic diabetic wounds.

Role of functionalized self-assembled peptide hydrogels in in vitro vasculogenesis

Fabrication of vascularized tissue constructs plays an integral role in creating clinically relevant tissues. Scaffold materials should be sufficiently vascularized to mimic functional and complex native tissues. Herein, we report the development of bioactive and biomimetic self-assembled peptide (SAP) hydrogels that allow the rapid formation of a vascular structure in vitro. The KLDLKLDLKLDL (KLD peptide) SAP was functionalized with laminin derived peptides IKVAV (V1) and YIGSR (V2) through direct coupling to mimic the natural extracellular matrix (ECM) and human umbilical endothelial cells (HUVECs) and mesenchymal stem cells (MSCs) cultured in 0.5% and 1% SAP hydrogels organized into vascularized structures. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) images proved the molecular integration of the nanofibrous structure in SAP hydrogels. The stability of SAP hydrogels was confirmed by rheological and degradation measurements. Bioactive peptide scaffolds enhanced significantly HUVEC/hMSC proliferation depicted by MTT analysis compared to KLD. Furthermore, the real time quantitative polymerase chain reaction (rt-PCR) was performed to analyse vascular gene expressions such as platelet/endothelial cell adhesion molecule-1 (PECAM-1), von Willebrand factor (vWF), and vascular endothelial cadherin (VE-cadherin). The results indicated that the KLD-V2 hydrogel significantly induced vasculogenesis in hMSC/HUVEC co-culture compared to KLD-V1, Biogelx and KLD because YIGSR in KLD-V2 promoted cell population and ECM secretion by the interaction with cells and increased vasculogenesis. Overall, the designed SAP hydrogel represents an effective scaffold for vascularization of tissue constructs with useful tissue engineering applications.

Physical and mechanical cues affecting biomaterial-mediated plasmid DNA delivery: insights into non-viral delivery systems

BACKGROUND

Whilst traditional strategies to increase transfection efficiency of non-viral systems aimed at modifying the vector or the polyplexes/lipoplexes, biomaterial-mediated gene delivery has recently sparked increased interest. This review aims at discussing biomaterial properties and unravelling underlying mechanisms of action, for biomaterial-mediated gene delivery. DNA internalisation and cytoplasmic transport are initially discussed. DNA immobilisation, encapsulation and surface-mediated gene delivery (SMD), the role of extracellular matrix (ECM) and topographical cues, biomaterial stiffness and mechanical stimulation are finally outlined.

MAIN TEXT

Endocytic pathways and mechanisms to escape the lysosomal network are highly variable. They depend on cell and DNA complex types but can be diverted using appropriate biomaterials. 3D scaffolds are generally fabricated via DNA immobilisation or encapsulation. Degradation rate and interaction with the vector affect temporal patterns of DNA release and transgene expression. In SMD, DNA is instead coated on 2D surfaces. SMD allows the incorporation of topographical cues, which, by inducing cytoskeletal re-arrangements, modulate DNA endocytosis. Incorporation of ECM mimetics allows cell type-specific transfection, whereas in spite of discordances in terms of optimal loading regimens, it is recognised that mechanical loading facilitates gene transfection. Finally, stiffer 2D substrates enhance DNA internalisation, whereas in 3D scaffolds, the role of stiffness is still dubious.

CONCLUSION

Although it is recognised that biomaterials allow the creation of tailored non-viral gene delivery systems, there still are many outstanding questions. A better characterisation of endocytic pathways would allow the diversion of cell adhesion processes and cytoskeletal dynamics, in order to increase cellular transfection. Further research on optimal biomaterial mechanical properties, cell ligand density and loading regimens is limited by the fact that such parameters influence a plethora of other different processes (e.g. cellular adhesion, spreading, migration, infiltration, and proliferation, DNA diffusion and release) which may in turn modulate gene delivery. Only a better understanding of these processes may allow the creation of novel robust engineered systems, potentially opening up a whole new area of biomaterial-guided gene delivery for non-viral systems.

Design Challenges in Polymeric Scaffolds for Tissue Engineering

Numerous surgical procedures are daily performed worldwide to replace and repair damaged tissue. Tissue engineering is the field devoted to the regeneration of damaged tissue through the incorporation of cells in biocompatible and biodegradable porous constructs, known as scaffolds. The scaffolds act as host biomaterials of the incubating cells, guiding their attachment, growth, differentiation, proliferation, phenotype, and migration for the development of new tissue. Furthermore, cellular behavior and fate are bound to the biodegradation of the scaffold during tissue generation. This article provides a critical appraisal of how key biomaterial scaffold parameters, such as structure architecture, biochemistry, mechanical behavior, and biodegradability, impart the needed morphological, structural, and biochemical cues for eliciting cell behavior in various tissue engineering applications. Particular emphasis is given on specific scaffold attributes pertaining to skin and brain tissue generation, where further progress is needed (skin) or the research is at a relatively primitive stage (brain), and the enumeration of some of the most important challenges regarding scaffold constructs for tissue engineering.

Polymeric Delivery of Therapeutic Nucleic Acids

The advent of genome editing has transformed the therapeutic landscape for several debilitating diseases, and the clinical outlook for gene therapeutics has never been more promising. The therapeutic potential of nucleic acids has been limited by a reliance on engineered viral vectors for delivery. Chemically defined polymers can remediate technological, regulatory, and clinical challenges associated with viral modes of gene delivery. Because of their scalability, versatility, and exquisite tunability, polymers are ideal biomaterial platforms for delivering nucleic acid payloads efficiently while minimizing immune response and cellular toxicity. While polymeric gene delivery has progressed significantly in the past four decades, clinical translation of polymeric vehicles faces several formidable challenges. The aim of our Account is to illustrate diverse concepts in designing polymeric vectors towards meeting therapeutic goals of in vivo and ex vivo gene therapy. Here, we highlight several classes of polymers employed in gene delivery and summarize the recent work on understanding the contributions of chemical and architectural design parameters. We touch upon characterization methods used to visualize and understand events transpiring at the interfaces between polymer, nucleic acids, and the physiological environment. We conclude that interdisciplinary approaches and methodologies motivated by fundamental questions are key to designing high-performing polymeric vehicles for gene therapy.

Hyaluronic acid and chondroitin sulfate (meth)acrylate-based hydrogels for tissue engineering: Synthesis, characteristics and pre-clinical evaluation

Hydrogels based on photocrosslinkable Hyaluronic Acid Methacrylate (HAMA) and Chondroitin Sulfate Methacrylate (CSMA) are presently under investigation for tissue engineering applications. HAMA and CSMA gels offer tunable characteristics such as tailorable mechanical properties, swelling characteristics, and enzymatic degradability. This review gives an overview of the scientific literature published regarding the pre-clinical development of covalently crosslinked hydrogels that (partially) are based on HAMA and/or CSMA. Throughout the review, recommendations for the next steps in clinical translation of hydrogels based on HAMA or CSMA are made and potential pitfalls are defined. Specifically, a myriad of different synthetic routes to obtain polymerizable hyaluronic acid and chondroitin sulfate derivatives are described. The effects of important parameters such as degree of (meth)acrylation and molecular weight of the synthesized polymers on the formed hydrogels are discussed and useful analytical techniques for their characterization are summarized. Furthermore, the characteristics of the formed hydrogels including their enzymatic degradability are discussed. Finally, a summary of several recent applications of these hydrogels in applied fields such as cartilage and cardiac regeneration and advanced tissue modelling is presented.

Potential Applications of Nanomaterials and Technology for Diabetic Wound Healing

Diabetic wound shows delayed and incomplete healing processes, which in turn exposes patients to an environment with a high risk of infection. This article has summarized current developments of nanoparticles/hydrogels and nanotechnology used for promoting the wound healing process in either diabetic animal models or patients with diabetes mellitus. These nanoparticles/hydrogels promote diabetic wound healing by loading bioactive molecules (such as growth factors, genes, proteins/peptides, stem cells/exosomes, etc.) and non-bioactive substances (metal ions, oxygen, nitric oxide, etc.). Among them, smart hydrogels (a very promising method for loading many types of bioactive components) are currently favored by researchers. In addition, nanoparticles/hydrogels can be combined with some technology (including PTT, LBL self-assembly technique and 3D-printing technology) to treat diabetic wound repair. By reviewing the recent literatures, we also proposed new strategies for improving multifunctional treatment of diabetic wounds in the future.

Hydrogel-Based Localized Nonviral Gene Delivery in Regenerative Medicine Approaches-An Overview

Hydrogel-based nonviral gene delivery constitutes a powerful strategy in various regenerative medicine scenarios, as those concerning the treatment of musculoskeletal, cardiovascular, or neural tissues disorders as well as wound healing. By a minimally invasive administration, these systems can provide a spatially and temporarily defined supply of specific gene sequences into the target tissue cells that are overexpressing or silencing the original gene, which can promote natural repairing mechanisms to achieve the desired effect. In the present work, we provide an overview of the most avant-garde approaches using various hydrogels systems for controlled delivery of therapeutic nucleic acid molecules in different regenerative medicine approaches.

Bioactive ECM Mimic Hyaluronic Acid Dressing via Sustained Releasing of bFGF for Enhancing Skin Wound Healing

Successful dermal wound regeneration requires the coordination of repair cells and cellular signals with the extracellular matrix (ECM), which serves as an indispensable mechanical and biological supporter for cell functions and communications with varied cytokines during healing processes. Here, we developed an injectable bioactive wound dressing, methacrylated hyaluronic acid (Me-HA)-based hydrogel loading with basic fibroblast growth factor (bFGF), endowing the dressing with the pleiotropic bioactivity to mimic natural ECM. This bFGF@Me-HA dressing was applied to a mouse with full-thickness excisional wounds to investigate its positive roles in wound repair owing to the complementary functions of HA with sustained release of bioactive bFGF. Compared with the single Me-HA and bFGF group, bFGF@Me-HA hydrogel dressings significantly enhanced wound healing with accelerated re-epithelialization, granulation formation, collagen, deposition and skin appendage regeneration. Further investigations showed significantly promoted cell proliferation and vascularization in the bFGF@Me-HA group, which was mediated by the upregulation of transforming growth factor-β (TGF-β) and vascular endothelial growth factor (VEGF) expressions. In conclusion, this bFGF@Me-HA hydrogel realized the optimization of simple ECM mimic dressing via introducing the bioactive effector, bFGF, and has the potential to be widely used as an effective bioactive ECM-based wound dressing in future wound care.

Porous Biomimetic Hyaluronic Acid and Extracellular Matrix Protein Nanofiber Scaffolds for Accelerated Cutaneous Tissue Repair

Recent reports suggest the utility of extracellular matrix (ECM) molecules as raw components in scaffolding of engineered materials. However, rapid and tunable manufacturing of ECM molecules into fibrous structures remains poorly developed. Here we report on an immersion rotary jet-spinning (iRJS) method to show high-throughput manufacturing (up to ∼1 g/min) of hyaluronic acid (HA) and other ECM fiber scaffolds using different spinning conditions and postprocessing modifications. This system allowed control over a variety of scaffold material properties, which enabled the fabrication of highly porous (70-95%) and water-absorbent (swelling ratio ∼2000-6000%) HA scaffolds with soft-tissue mimetic mechanical properties (∼0.5-1.5 kPa). Tuning these scaffolds' properties enabled the identification of porosity (∼95%) as a key facilitator for rapid and in-depth cellular ingress in vitro. We then demonstrated that porous HA scaffolds accelerated granulation tissue formation, neovascularization, and reepithelialization in vivo, altogether potentiating faster wound closure and tissue repair. Collectively, this scalable and versatile manufacturing approach enabled the fabrication of tunable ECM-mimetic nanofiber scaffolds that may provide an ideal first building block for the design of all-in-one healing materials.

Injectable, Hyaluronic Acid-Based Scaffolds with Macroporous Architecture for Gene Delivery

INTRODUCTION

Biomaterials can provide localized reservoirs for controlled release of therapeutic biomolecules and drugs for applications in tissue engineering and regenerative medicine. As carriers of gene-based therapies, biomaterial scaffolds can improve efficiency and delivery-site localization of transgene expression. Controlled delivery of gene therapy vectors from scaffolds requires cell-scale macropores to facilitate rapid host cell infiltration. Recently, advanced methods have been developed to form injectable scaffolds containing cell-scale macropores. However, relative efficacy of in vivo gene delivery from scaffolds formulated using these general approaches has not been previously investigated. Using two of these methods, we fabricated scaffolds based on hyaluronic acid (HA) and compared how their unique, macroporous architectures affected their respective abilities to deliver transgenes via lentiviral vectors in vivo.

METHODS

Three types of scaffolds-nanoporous HA hydrogels (NP-HA), annealed HA microparticles (HA-MP) and nanoporous HA hydrogels containing protease-degradable poly(ethylene glycol) (PEG) microparticles as sacrificial porogens (PEG-MP)-were loaded with lentiviral particles encoding reporter transgenes and injected into mouse mammary fat. Scaffolds were evaluated for their ability to induce rapid infiltration of host cells and subsequent transgene expression.

RESULTS

Cell densities in scaffolds, distances into which cells penetrated scaffolds, and transgene expression levels significantly increased with delivery from HA-MP, compared to NP-HA and PEG-MP, scaffolds. Nearly 8-fold greater cell densities and up to 16-fold greater transgene expression levels were found in HA-MP, over NP-HA, scaffolds. Cell profiling revealed that within HA-MP scaffolds, macrophages (F4/80+), fibroblasts (ERTR7+) and endothelial cells (CD31+) were each present and expressed delivered transgene.

CONCLUSIONS

Results demonstrate that injectable scaffolds containing cell-scale macropores in an open, interconnected architecture support rapid host cell infiltration to improve efficiency of biomaterial-mediated gene delivery.

Hydrogel vehicles for sequential delivery of protein drugs to promote vascular regeneration

In recent years, as the mechanisms of vasculogenesis and angiogenesis have been uncovered, the functions of various pro-angiogenic growth factors (GFs) and cytokines have been identified. Therefore, therapeutic angiogenesis, by delivery of GFs, has been sought as a treatment for many vascular diseases. However, direct injection of these protein drugs has proven to have limited clinical success due to their short half-lives and systemic off-target effects. To overcome this, hydrogel carriers have been developed to conjugate single or multiple GFs with controllable, sustained, and localized delivery. However, these attempts have failed to account for the temporal complexity of natural angiogenic pathways, resulting in limited therapeutic effects. Recently, the emerging ideas of optimal sequential delivery of multiple GFs have been suggested to better mimic the biological processes and to enhance therapeutic angiogenesis. Incorporating sequential release into drug delivery platforms will likely promote the formation of neovasculature and generate vast therapeutic potential.

Bioprinting of Vascularized Tissue Scaffolds: Influence of Biopolymer, Cells, Growth Factors, and Gene Delivery

Over the past decades, tissue regeneration with scaffolds has achieved significant progress that would eventually be able to solve the worldwide crisis of tissue and organ regeneration. While the recent advancement in additive manufacturing technique has facilitated the biofabrication of scaffolds mimicking the host tissue, thick tissue regeneration remains challenging to date due to the growing complexity of interconnected, stable, and functional vascular network within the scaffold. Since the biological performance of scaffolds affects the blood vessel regeneration process, perfect selection and manipulation of biological factors (i.e., biopolymers, cells, growth factors, and gene delivery) are required to grow capillary and macro blood vessels. Therefore, in this study, a brief review has been presented regarding the recent progress in vasculature formation using single, dual, or multiple biological factors. Besides, a number of ways have been presented to incorporate these factors into scaffolds. The merits and shortcomings associated with the application of each factor have been highlighted, and future research direction has been suggested.

Biomaterial substrate modifications that influence cell-material interactions to prime cellular responses to nonviral gene delivery

IMPACT STATEMENT

This review summarizes how biomaterial substrate modifications (e.g. chemical modifications like natural coatings, ligands, or functional side groups, and/or physical modifications such as topography or stiffness) can prime the cellular response to nonviral gene delivery (e.g. affecting integrin binding and focal adhesion formation, cytoskeletal remodeling, endocytic mechanisms, and intracellular trafficking), to aid in improving gene delivery for applications where a cell-material interface might exist (e.g. tissue engineering scaffolds, medical implants and devices, sensors and diagnostics, wound dressings).

Surface- and Hydrogel-Mediated Delivery of Nucleic Acid Nanoparticles

Gene expression within a cell population can be directly altered through gene delivery approaches. Traditionally for nonviral delivery, plasmids or siRNA molecules, encoding or targeting the gene of interest, are packaged within nanoparticles. These nanoparticles are then delivered to the media surrounding cells seeded onto tissue culture plastic; this technique is termed bolus delivery. Although bolus delivery is widely utilized to screen for efficient delivery vehicles and to study gene function in vitro, this delivery strategy may not result in efficient gene transfer for all cell types or may not identify those delivery vehicles that will be efficient in vivo. Furthermore, bolus delivery cannot be used in applications where patterning of gene expression is needed. In this chapter, we describe methods that incorporate material surfaces (i.e., surface-mediated delivery) or hydrogel scaffolds (i.e., hydrogel-mediated delivery) to efficiently deliver genes. This chapter includes protocols for surface-mediated DNA delivery focusing on the simplest and most effective methods, which include nonspecific immobilization of DNA complexes (both polymer and lipid vectors) onto serum-coated cell culture polystyrene and self-assembled monolayers (SAMs) of alkanethiols on gold. Also, protocols for the encapsulation of DNA/cationic polymer nanoparticles into hydrogel scaffolds are described, including methods for the encapsulation of low amounts of DNA (<0.2 μg/μl) and high amounts of DNA (>0.2 μg/μl) since incorporation of high amounts of DNA pose significant challenges due to aggregation.

Shear-thinning hyaluronan-based fluid hydrogels to modulate viscoelastic properties of osteoarthritis synovial fluids

Hyaluronan-based injectable fluid hydrogel was prepared and used as an artificial synovial fluid for the treatment of osteoarthritis.

Hyaluronic acid hydrogel scaffolds loaded with cationic niosomes for efficient non-viral gene delivery

The lack of ideal non-viral gene carriers has motivated the combination of delivery systems and tissue-engineered scaffolds, which may offer relevant advantages such as enhanced stability and reduced toxicity. In this work, we evaluated a new combination between niosome non-viral vectors and hyaluronic acid (HA) hydrogel scaffolds, both widely studied due to their biocompatibility as well as their ability to incorporate a wide variety of molecules. We evaluated three different niosome formulations (niosomes 1, 2 and 3) varying in composition of cationic lipid, helper lipid and non-ionic tensioactives. Niosomes and nioplexes obtained upon the addition of plasmid DNA were characterized in terms of size, polydispersity, zeta potential and ability to transfect mouse bone marrow cloned mesenchymal stem cells (mMSCs) in 2D culture. Niosome 1 was selected for encapsulation in HA hydrogels due to its higher transfection efficiency and the formulation was concentrated in order to be able to incorporate higher amounts of DNA within HA hydrogels. Nioplex-loaded HA hydrogels were characterized in terms of biomechanical properties, particle distribution, nioplex release kinetics and ability to transfect encapsulated mMSCs in 3D culture. Our results showed that nioplex-loaded HA hydrogel scaffolds presented little or no particle aggregation, allowed for extensive cell spreading and were able to efficiently transfect encapsulated mMSCs with high cellular viability. We believe that the knowledge gained through this in vitro model can be utilized to design novel and effective platforms for in vivo local and non-viral gene delivery applications.

Nioplexes encapsulated in HA hydrogel scaffolds present no particle aggregation, incorporate high amount of DNA, allow extensive cell spreading and are able to efficiently transfect mesenchymal stem cells in 3D cultures with high cellular viability.

It's All in the Delivery: Designing Hydrogels for Cell and Non-viral Gene Therapies

Hydrogels provide a regenerative medicine platform with their ability to create an environment that supports transplanted or endogenous infiltrating cells and enables these cells to restore or replace the function of tissues lost to disease or trauma. Furthermore, these systems have been employed as delivery vehicles for therapeutic genes, which can direct and/or enhance the function of the transplanted or endogenous cells. Herein, we review recent advances in the development of hydrogels for cell and non-viral gene delivery through understanding the design parameters, including both physical and biological components, on promoting transgene expression, cell engraftment, and ultimately cell function. Furthermore, this review identifies emerging opportunities for combining cell and gene delivery approaches to overcome challenges to the field.

Correlation of the cytotoxic effects of cationic lipids with their headgroups

As effective non-viral vectors of gene therapy, cationic lipids still have the problem of toxicity, which has become one of the main bottlenecks for their applications. The toxicity of cationic lipids is strongly connected to the headgroup structures. In this article, we studied the cytotoxicity of two cationic lipids with a quaternary ammonium headgroup (CDA14) and a tri-peptide headgroup (CDO14), respectively, and with the same linker bond and hydrophobic domain. The IC50 values of CDA14 and CDO14 against NCI-H460 cells were 109.4 μg mL-1 and 340.5 μg mL-1, respectively. To determine the effects of headgroup structures of cationic lipids on cytotoxicity, apoptosis related pathways were investigated. As the lipids with a quaternary ammonium headgroup could induce more apoptotic cells than the ones with a peptide headgroup, the enzymatic activity of caspase-9 and caspase-3 increased obviously, whereas the mitochondrial membrane potential (MMP) decreased. At the same time, the reactive oxygen species (ROS) levels also increased and the cell cycle was arrested at the S phase. The results showed that the toxicity of the cationic lipid had a close relationship with its headgroup structures, and the cytotoxic mechanism was mainly via the caspase activation dependent signaling pathway and mitochondrial dysfunction. Through this study, we hope to provide the scientific basis for exploiting safer and more efficient cationic lipids for gene delivery.

In Situ Organ-Specific Vascularization in Tissue Engineering

Other than a few avascular tissues, almost all human tissues are connected to the systemic circulation via blood vessels that promote metabolism and function. Accordingly, engineered vascularization is a vital goal in tissue engineering for regenerative medicine. Endothelial cells (ECs) play a central role in vascularization with two significant specificities: physical interfaces between vascular stroma and blood, and phenotypic organ-specificity. Biomaterial scaffolding technologies that address these unique properties of ECs have been developed to promote the vascularization of various engineered tissues, and these have advanced from mimicking vascular architectures ex situ towards promoting spontaneous angiogenic remodeling in situ. Simultaneously, endothelial progenitor cells (EPCs) and organ-specific ECs are attracting more and more attention with the increasing awareness of the diversity of ECs in different organs.

Non-viral gene delivery systems for tissue repair and regeneration

Critical tissue defects frequently result from trauma, burns, chronic wounds and/or surgery. The ideal treatment for such tissue loss is autografting, but donor sites are often limited. Tissue engineering (TE) is an inspiring alternative for tissue repair and regeneration (TRR). One of the current state-of-the-art methods for TRR is gene therapy. Non-viral gene delivery systems (nVGDS) have great potential for TE and have several advantages over viral delivery including lower immunogenicity and toxicity, better cell specificity, better modifiability, and higher productivity. However, there is no ideal nVGDS for TRR, hence, there is widespread research to improve their properties. This review introduces the basic principles and key aspects of commonly-used nVGDSs. We focus on recent advances in their applications, current challenges, and future directions.

Redox-responsive micelles from disulfide bond-bridged hyaluronic acid-tocopherol succinate for the treatment of melanoma

Nanotechnology-based chemotherapy is efficient in cancer treatment due to the targeted delivery of small molecules via nano-carriers, which are usually regarded as "inert". However, nano-materials are more preferred as carriers since many cause synergistic anti-tumor effects along with the drug cargo. In this study, a "bioactive" tocopherol succinate (TOS) was grafted to hyaluronic acid (HA) via of disulfide bonds to obtain HA-ss-TOS conjugates which can assemble into nano-micelles but dissociate when exposed to reducing environments in vitro and in vivo. Moreover, paclitaxel-loaded HA-ss-TOS micelles (HA-ss-TOS-PTX) can be efficiently taken up by B16F10 cells overexpressing CD 44, thereafter exhibiting enhanced cytotoxicity. The in vivo imaging study here revealed much greater tumor accumulation of Dir-labeled HA-ss-TOS compared to the free Dir group. In vivo antitumor activities further ensured that the PTX-loaded HA-ss-TOS micelles provided superior antineoplastic responses versus PTX-loaded HA-TOS micelles and Taxol. Moreover, the subcellular dissociated TOS from HA-ss-TOS showed synergistic effects with PTX. These experimental results revealed that reduction-responsive PTX-loaded polymeric nano-micelles with multi-functional properties hold great potential for anti-tumor treatment and, thus, should be further studied.

Polymers and hydrogels for local nucleic acid delivery

This review focusses on the rational design of materials (from polymers to hydrogel materials) to achieve successful local delivery of therapeutic nucleic acids.

Modeling angiogenesis with micro- and nanotechnology

Angiogenesis plays an important role not only in the growth and regeneration of tissues in humans but also in pathological conditions such as inflammation, degenerative disease and the formation of tumors. Angiogenesis is also vital in thick engineered tissues and constructs, such as those for the heart and bone, as these can face difficulties in successful implantation if they are insufficiently vascularized or unable to connect to the host vasculature. Considerable research has been carried out on angiogenic processes using a variety of approaches. Pathological angiogenesis has been analyzed at the cellular level through investigation of cell migration and interactions, modeling tissue level interactions between engineered blood vessels and whole organs, and elucidating signaling pathways involved in different angiogenic stimuli. Approaches to regenerative angiogenesis in ischemic tissues or wound repair focus on the vascularization of tissues, which can be broadly classified into two categories: scaffolds to direct and facilitate tissue growth and targeted delivery of genes, cells, growth factors or drugs that promote the regeneration. With technological advancement, models have been designed and fabricated to recapitulate the innate microenvironment. Moreover, engineered constructs provide not only a scaffold for tissue ingrowth but a reservoir of agents that can be controllably released for therapeutic purposes. This review summarizes the current approaches for modeling pathological and regenerative angiogenesis in the context of micro-/nanotechnology and seeks to bridge these two seemingly distant aspects of angiogenesis. The ultimate aim is to provide insights and advances from various models in the realm of angiogenesis studies that can be applied to clinical situations.

Directing three-dimensional multicellular morphogenesis by self-organization of vascular mesenchymal cells in hyaluronic acid hydrogels

BACKGROUND

Physical scaffolds are useful for supporting cells to form three-dimensional (3D) tissue. However, it is non-trivial to develop a scheme that can robustly guide cells to self-organize into a tissue with the desired 3D spatial structures. To achieve this goal, the rational regulation of cellular self-organization in 3D extracellular matrix (ECM) such as hydrogel is needed.

RESULTS

In this study, we integrated the Turing reaction-diffusion mechanism with the self-organization process of cells and produced multicellular 3D structures with the desired configurations in a rational manner. By optimizing the components of the hydrogel and applying exogenous morphogens, a variety of multicellular 3D architectures composed of multipotent vascular mesenchymal cells (VMCs) were formed inside hyaluronic acid (HA) hydrogels. These 3D architectures could mimic the features of trabecular bones and multicellular nodules. Based on the Turing reaction-diffusion instability of morphogens and cells, a theoretical model was proposed to predict the variations observed in 3D multicellular structures in response to exogenous factors. It enabled the feasibility to obtain diverse types of 3D multicellular structures by addition of Noggin and/or BMP2.

CONCLUSIONS

The morphological consistency between the simulation prediction and experimental results probably revealed a Turing-type mechanism underlying the 3D self-organization of VMCs in HA hydrogels. Our study has provided new ways to create a variety of self-organized 3D multicellular architectures for regenerating biomaterial and tissues in a Turing mechanism-based approach.

Injectable supramolecular hydrogel formed from α-cyclodextrin and PEGylated arginine-functionalized poly(l-lysine) dendron for sustained MMP-9 shRNA plasmid delivery

Hydrogels have attracted much attention in cancer therapy and tissue engineering due to their sustained gene delivery ability. To obtain an injectable and high-efficiency gene delivery hydrogel, methoxypolyethylene glycol (MPEG) was used to conjugate with the arginine-functionalized poly(l-lysine) dendron (PLLD-Arg) by click reaction, and then the synthesized MPEG-PLLD-Arg interacted with α-cyclodextrin (α-CD) to form the supramolecular hydrogel by the host-guest interaction. The gelation dynamics, hydrogel strength and shear viscosity could be modulated by α-CD content in the hydrogel. MPEG-PLLD-Arg was confirmed to bind and deliver gene effectively, and its gene transfection efficiency was significantly higher than PEI-25k under its optimized condition. After gelation, MMP-9 shRNA plasmid (pMMP-9) could be encapsulated into the hydrogel matrix in situ and be released from the hydrogels sustainedly, as the release rate was dependent on α-CD content. The released MPEG-PLLD-Arg/pMMP-9 complex still showed better transfection efficiency than PEI-25k and induced sustained tumor cell apoptosis. Also, in vivo assays indicated that this pMMP-9-loaded supramolecular hydrogel could result in the sustained tumor growth inhibition meanwhile showed good biocompatibility. As an injectable, sustained and high-efficiency gene delivery system, this supramolecular hydrogel is a promising candidate for long-term gene therapy.

STATEMENT OF SIGNIFICANCE

To realize the sustained gene delivery for gene therapy, a supramolecular hydrogel with high-efficiency gene delivery ability was prepared through the host-guest interaction between α-cyclodextrin and PEGylated arginine-functionalized poly(l-lysine) dendron. The obtained hydrogel was injectable and biocompatible with adjustable physicochemical property. More importantly, the hydrogel showed the high-efficiency and sustained gene transfection to our used cells, better than PEI-25k. The supramolecular hydrogel resulted in the sustained tumor growth inhibition meanwhile keep good biocompatibility. As an injectable, sustained and high-efficiency gene delivery system, this supramolecular hydrogel is a promising candidate in long-term gene therapy and tissue engineering.

Hydration of hydrogels regulates vascularization in vivo

The key barrier to the clinical application of tissue engineering scaffolds is the limitation of rapid and sufficient vascularization.

Neovascularization Induced by the Hyaluronic Acid-Based Spongy-Like Hydrogels Degradation Products

Neovascularization has been a major challenge in many tissue regeneration strategies. Hyaluronic acid (HA) of 3-25 disaccharides is known to be angiogenic due to its interaction with endothelial cell receptors. This effect has been explored with HA-based structures but a transitory response is observed due to HA burst biodegradation. Herein we developed gellan gum (GG)-HA spongy-like hydrogels from semi-interpenetrating network hydrogels with different HA amounts. Enzymatic degradation was more evident in the GG-HA with high HA amount due to their lower mechanical stability, also resulting from the degradation itself, which facilitated the access of the enzyme to the HA in the bulk. GG-HA spongy-like hydrogels hyaluronidase-mediated degradation lead to the release of HA oligosaccharides of different amounts and sizes in a HA content-dependent manner which promoted in vitro proliferation of human umbilical cord vein endothelial cells (HUVECs) but not their migration. Although no effect was observed in human dermal microvascular endothelial cells (hDMECs) in vitro, the implantation of GG-HA spongy-like hydrogels in an ischemic hind limb mice model promoted neovascularization in a material-dependent manner, consistent with the in vitro degradation profile. Overall, GG-HA spongy-like hydrogels with a sustained release of HA oligomers are valuable options to improve tissue vascularization, a critical issue in several applications in the tissue engineering and regenerative medicine field.

Light-triggered RNA release and induction of hMSC osteogenesis via photodegradable, dual-crosslinked hydrogels

AIM

To engineer a photodegradable hydrogel system for actively controlled release of bioactive unmodified RNA at designated time points to induce hMSC osteogenesis.

MATERIALS & METHODS

RNA/polyethylenimine complexes were loaded into dual-crosslinked photodegradable hydrogels to examine the capacity of UV light application to trigger their release. The ability of released RNA to drive hMSC osteogenic differentiation was also investigated.

RESULTS & CONCLUSION

RNA release from photodegradable hydrogels was accelerated upon UV application, which was not observed in non-photodegradable hydrogels. Regardless of the presence of UV light, released siGFP exhibited high bioactivity by silencing GFP expression in HeLa cells. Importantly, siNoggin or miRNA-20a released from the hydrogels induced hMSC osteogenesis. This system provides a potentially valuable physician/patient-controlled 'on-demand' RNA delivery platform for biomedical applications.

Hydrogel as a bioactive material to regulate stem cell fate

The encapsulation of stem cells in a hydrogel substrate provides a promising future in biomedical applications. However, communications between hydrogels and stem cells is complicated; various factors such as porosity, different polymer types, stiffness, compatibility and degradation will lead to stem cell survival or death. Hydrogels mimic the three-dimensional extracellular matrix to provide a friendly environment for stem cells. On the other hand, stem cells can sense the surroundings to make the next progression, stretching out, proliferating or just to remain. As such, understanding the correlation between stem cells and hydrogels is crucial. In this Review, we first discuss the varying types of the hydrogels and stem cells, which are most commonly used in the biomedical fields and further investigate how hydrogels interact with stem cells from the perspective of their biomedical application, while providing insights into the design and development of hydrogels for drug delivery, tissue engineering and regenerative medicine purpose. In addition, we compare the results such as stiffness, degradation time and pore size as well as peptide types of hydrogels from respected journals. We also discussed most recently magnificent materials and their effects to regulate stem cell fate.

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Hydrogels as Extracellular Matrix (ECM) mimics stem cells proliferation and differentiation.

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Discuss how hydrogels interact with stem cells from the perspective of their biomedical applications.

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Recent magnificent materials and their effects to regulate stem cells fate.

Hydrogels for brain repair after stroke: an emerging treatment option

Stroke disability is the only major disease without an effective treatment. The substantial clinical burden of stroke in disabled survivors and the lack of a medical therapy that promotes recovery provide an opportunity to explore the use of biomaterials to promote brain repair after stroke. Hydrogels can be injected as a liquid and solidify in situ to form a gelatinous solid with similar mechanical properties to the brain. These biomaterials have been recently explored to generate pro-repair environments within the damaged organ. This review highlights the clinical problem of stroke treatment and discusses recent advances in using in situ forming hydrogels for brain repair.

Functional nucleic acid-based hydrogels for bioanalytical and biomedical applications

Hydrogels are crosslinked hydrophilic polymers that can absorb a large amount of water. By their hydrophilic, biocompatible and highly tunable nature, hydrogels can be tailored for applications in bioanalysis and biomedicine. Of particular interest are DNA-based hydrogels owing to the unique features of nucleic acids. Since the discovery of the DNA double helical structure, interest in DNA has expanded beyond its genetic role to applications in nanotechnology and materials science. In particular, DNA-based hydrogels present such remarkable features as stability, flexibility, precise programmability, stimuli-responsive DNA conformations, facile synthesis and modification. Moreover, functional nucleic acids (FNAs) have allowed the construction of hydrogels based on aptamers, DNAzymes, i-motif nanostructures, siRNAs and CpG oligodeoxynucleotides to provide additional molecular recognition, catalytic activities and therapeutic potential, making them key players in biological analysis and biomedical applications. To date, a variety of applications have been demonstrated with FNA-based hydrogels, including biosensing, environmental analysis, controlled drug release, cell adhesion and targeted cancer therapy. In this review, we focus on advances in the development of FNA-based hydrogels, which have fully incorporated both the unique features of FNAs and DNA-based hydrogels. We first introduce different strategies for constructing DNA-based hydrogels. Subsequently, various types of FNAs and the most recent developments of FNA-based hydrogels for bioanalytical and biomedical applications are described with some selected examples. Finally, the review provides an insight into the remaining challenges and future perspectives of FNA-based hydrogels.

Encapsulation of PEGylated low-molecular-weight PEI polyplexes in hyaluronic acid hydrogels reduces aggregation

The effective delivery of DNA locally could increase the applicability of gene therapy in tissue regeneration and therapeutic angiogenesis. One promising approach is through use of porous hydrogel scaffolds that incorporate and deliver DNA in the form of nanoparticles to the affected sites. While we have previously reported on caged nanoparticle encapsulation (CnE) to load DNA polyplexes within hydrogels at high concentrations without aggregation, frequent issues with limited polyplex release following CnE have been encountered. In this study, we report two alternative approaches to polyplex presentation for decreasing aggregation in porous hydrogels. The first approach reduces polyplex aggregation by utilizing polyethylene glycol modification of the gene carrier polymer polyethyleneimine (sPEG-PEI) to mitigate charge-charge interactions between polyplexes and the scaffold during gelation. The second approach electrostatically presents polyplexes on the surfaces of scaffold pores as opposed to an encapsulated presentation. The sPEG-PEI polymer formed a smaller, less toxic, and more stable polyplex that exhibited less aggregation within HA gels when compared to the traditionally used linear PEI (LPEI) polymer. Surface-coated polyplexes also resulted in a more homogenous distribution of polyplexes in hydrogels. Furthermore, sPEG-PEI polyplexes retained transfection abilities comparable to LPEI in 3D surface-coated transfections. These results demonstrate a significant improvement in scaffold-mediated gene delivery and show promise in applications to multi-gene delivery systems.

STATEMENT OF SIGNIFICANCE

A promising gene delivery approach for regenerative medicine is implanting porous hydrogel scaffolds loaded with DNA nanoparticles for delivery to affected sites. However, loading DNA polyplexes at high concentrations within hydrogels results in significant aggregation. Here, we describe two methods for decreasing aggregation of DNA polyplexes in porous gels. First, the gene carrier polymer polyethyleneimine (PEI) was modified with polyethylene glycol (sPEG-PEI) to mitigate the electrostatic interactions between polyplexes and scaffold polymer to in turn decrease aggregation. Second, polyplexes were presented along the surfaces of the pores of the hydrogel instead of being encapsulated within the gel. These methods allow for highly tunable and sustained transgene expression from scaffold-mediated gene delivery while avoiding polyplex aggregation.

Technologies for controlled, local delivery of siRNA

The discovery of RNAi in the late 1990s unlocked a new realm of therapeutic possibilities by enabling potent and specific silencing of theoretically any desired genetic target. Better elucidation of the mechanism of action, the impact of chemical modifications that stabilize and reduce nonspecific effects of siRNA molecules, and the key design considerations for effective delivery systems has spurred progress toward developing clinically-successful siRNA therapies. A logical aim for initial siRNA translation is local therapies, as delivering siRNA directly to its site of action helps to ensure that a sufficient dose reaches the target tissue, lessens the potential for off-target side effects, and circumvents the substantial systemic delivery barriers. While locally injected or topically applied siRNA has progressed into numerous clinical trials, an enormous opportunity exists to develop sustained-release, local delivery systems that enable both spatial and temporal control of gene silencing. This review focuses on material platforms that establish both localized and controlled gene silencing, with emphasis on the systems that show most promise for clinical translation.

Surface-mediated delivery of siRNA from fibrin hydrogels for knockdown of the BMP-2 binding antagonist noggin

Antagonists and inhibitory molecules responsible for maintaining tissue homeostasis can present a significant barrier to healing when tissue engineering/regenerative medicine strategies are employed. One example of this situation is the up-regulation of antagonists such as noggin in response to increasing concentrations of bone morphogenetic protein-2 (BMP-2) present from endogenous bone repair processes or delivered exogenously from biomaterials (synthetic bone grafts). While recombinant human (rh)BMP-2 delivered from synthetic bone grafts has been shown to be an effective alternative to autografts and allografts, the supraphysiological doses of rhBMP-2 have led to clinically-adverse side effects. The high rhBMP-2 dosage may be required, in part, to overcome the presence of antagonists such as noggin. Small interfering RNA (siRNA) is an appealing approach to overcome this problem because it can knock-down antagonists or inhibitory molecules in a temporary manner. Here, we conducted fundamental studies on the delivery of siRNA from material surfaces as a means to knock-down antagonists like noggin. Non-viral cationic lipid (Lipofectamine)-siRNA complexes were delivered from a fibrin hydrogel surface to MC3T3-E1 preosteoblasts that were treated with a supraphysiological dose of rhBMP-2 to achieve noggin mRNA expression levels higher than cells naïve to rhBMP-2. Confocal microscopy and flow cytometry showed intracellular uptake of siRNA in over 98% of MC3T3-E1 cells after 48 h. Doses of 0.5 and 1 μg noggin siRNA were able to significantly reduce noggin mRNA to levels equivalent to those in MC3T3-E1 cells not exposed to rhBMP-2 with no effects on cell viability.

STATEMENT OF SIGNIFICANCE

Small interfering RNA (siRNA) has been considered for treatment of diseases ranging from Alzheimer's to cancer. However, the ability to use siRNA in conjunction with biomaterials to direct tissue regeneration processes has received relatively little attention. Using the bone morphogenetic protein 2 antagonist, noggin, as a model, this research describes an approach to knock-down molecules that are inhibitory to desired regenerative pathways at the mRNA level via siRNA delivery from a hydrogel surface. Interactions between the material (fibrin) surface and polycation-siRNA complexes, release of the siRNA from the material surface, high levels of cellular uptake/internalization of siRNA, and significant knockdown of the targeting (noggin) mRNA are demonstrated. Broader future applications include those to nerve regeneration, cardiovascular tissue engineering, directing (stem) cell behavior, and mitigating inflammatory responses to materials.

Systematic evaluation of natural scaffolds in cutaneous wound healing

Current strategies to improve wound healing are often created from multiple components that may include a scaffold, cells, and bioactive cues. Acellular natural hydrogels are an attractive approach since the material's intrinsic biological activity can be paired with mechanical properties similar to soft tissue to induce a host's response toward healing. In this report, a systematic evaluation was conducted to study the effect of hydrogel scaffold implantation in skin healing using a human-relevant murine wound healing model. Fibrin, micro porous hyaluronic acid, and composite hydrogels were utilized to study the effect of conductive scaffolds on the wound healing process. Composite hydrogels were paired with plasmin-degradable VEGF nanocapsules to investigate its impact as an inductive composite hydrogel on tissue repair. By 7 days, wound healing and vessel maturation within the newly formed tissue was significantly improved by the inclusion of porous scaffold architecture and VEGF nanocapsules.

High Strength Multifunctional Multiwalled Hydrogel Tubes: Ion-Triggered Shape Memory, Antibacterial, and Anti-inflammatory Efficacies

In this study, ion-responsive hydrogen bonding strengthened hydrogels (termed as PVV) were synthesized by one-pot copolymerization of 2-vinyl-4,6-diamino-1,3,5-triazine (VDT), 1-vinylimidazole (VI), and polyethylene glycol diacrylate. The diaminotriazine-diaminotriazine (DAT-DAT) H-bonding interaction and copolymerization of VI contributed to a notable increase in comprehensive performances including tensile/compressive strength, elasticity, modulus, and fracture energy. In addition, introducing mM levels of zinc ions could further increase the mechanical properties of PVV hydrogels and fix a variety of temporary shapes due to the strong coordination of zinc with imidazole. The release of zinc ions from the hydrogel contributed to an antibacterial effect, without compromising the shape memory effect. Remarkably, a multiwalled hydrogel tube (MWHT) fixed with Zn(2+) demonstrated much higher flexural strengths and a more sustainable release of zinc ions than the solid hydrogel cylinder (SHC). A Zn(2+)-fixed MWHT was implanted subcutaneously in rats, and it was found that the Zn(2+)-fixed MWHT exhibited anti-inflammatory and wound healing efficacies. The reported high strength hydrogel with integrated functions holds potential as a tissue engineering scaffold.