Advances in pulmonary therapy and drug development: Lung tissue engineering to lung-on-a-chip.

PubMed

Doryab, Ali; Amoabediny, Ghassem; Salehi-Najafabadi, Amir

2016-01-01

Lung disease is one of the major causes of death, and the rate of pulmonary diseases has been increasing for decades. Although lung transplantation is the only treatment for majority of patients, this method has been limited due to lack of donors. Therefore, recently, attentions have increased to some new strategies with the aid of tissue engineering and microfluidics techniques not only for the functional analysis, but also for drug screening. In fact, in tissue engineering, the engineered tissue is able to grow by using the patient's own cells without intervention in the immune system. On the other hand, microfluidics devices are applied in order to evaluate drug screenings, function analysis and toxicity. This article reviews new advances in lung tissue engineering and lung-on-a-chip. Furthermore, future directions, difficulties and drawbacks of pulmonary therapy in these areas are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

Advances in Meniscal Tissue Engineering

PubMed Central

Longo, Umile Giuseppe; Loppini, Mattia; Forriol, Francisco; Romeo, Giovanni; Maffulli, Nicola; Denaro, Vincenzo

2012-01-01

Meniscal tears are the most common knee injuries and have a poor ability of healing. In the last few decades, several techniques have been increasingly used to optimize meniscal healing. Current research efforts of tissue engineering try to combine cell-based therapy, growth factors, gene therapy, and reabsorbable scaffolds to promote healing of meniscal defects. Preliminary studies did not allow to draw definitive conclusions on the use of these techniques for routine management of meniscal lesions. We performed a review of the available literature on current techniques of tissue engineering for the management of meniscal tears. PMID:25098366

Current and future regenerative medicine — Principles, concepts, and therapeutic use of stem cell therapy and tissue engineering in equine medicine

PubMed Central

Koch, Thomas G.; Berg, Lise C.; Betts, Dean H.

2009-01-01

This paper provides a bird’s-eye perspective of the general principles of stem-cell therapy and tissue engineering; it relates comparative knowledge in this area to the current and future status of equine regenerative medicine. The understanding of equine stem cell biology, biofactors, and scaffolds, and their potential therapeutic use in horses are rudimentary at present. Mesenchymal stem cell isolation has been proclaimed from several equine tissues in the past few years. Based on the criteria of the International Society for Cellular Therapy, most of these cells are more correctly referred to as multipotent mesenchymal stromal cells, unless there is proof that they exhibit the fundamental in vivo characteristics of pluripotency and the ability to self-renew. That said, these cells from various tissues hold great promise for therapeutic use in horses. The 3 components of tissue engineering — cells, biological factors, and biomaterials — are increasingly being applied in equine medicine, fuelled by better scaffolds and increased understanding of individual biofactors and cell sources. The effectiveness of stem cell-based therapies and most tissue engineering concepts has not been demonstrated sufficiently in controlled clinical trials in equine patients to be regarded as evidence-based medicine. In the meantime, the medical mantra “do no harm” should prevail, and the application of stem cell-based therapies in the horse should be done critically and cautiously, and treatment outcomes (good and bad) should be recorded and reported. Stem cell and tissue engineering research in the horse has exciting comparative and equine specific perspectives that most likely will benefit the health of horses and humans. Controlled, well-designed studies are needed to move this new equine research field forward. PMID:19412395

Tissue engineering applications of therapeutic cloning.

PubMed

Atala, Anthony; Koh, Chester J

2004-01-01

Few treatment options are available for patients suffering from diseased and injured organs because of a severe shortage of donor organs available for transplantation. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for replacement therapy. Scientists in the field of tissue engineering apply the principles of cell transplantation, material science, and engineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. The present chapter reviews recent advances that have occurred in therapeutic cloning and tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

Pericyte-targeting drug delivery and tissue engineering.

PubMed

Kang, Eunah; Shin, Jong Wook

2016-01-01

Pericytes are contractile mural cells that wrap around the endothelial cells of capillaries and venules. Depending on the triggers by cellular signals, pericytes have specific functionality in tumor microenvironments, properties of potent stem cells, and plasticity in cellular pathology. These features of pericytes can be activated for the promotion or reduction of angiogenesis. Frontier studies have exploited pericyte-targeting drug delivery, using pericyte-specific peptides, small molecules, and DNA in tumor therapy. Moreover, the communication between pericytes and endothelial cells has been applied to the induction of vessel neoformation in tissue engineering. Pericytes may prove to be a novel target for tumor therapy and tissue engineering. The present paper specifically reviews pericyte-specific drug delivery and tissue engineering, allowing insight into the emerging research targeting pericytes.

Myocardial Tissue Engineering for Regenerative Applications.

PubMed

Fujita, Buntaro; Zimmermann, Wolfram-Hubertus

2017-09-01

This review provides an overview of the current state of tissue-engineered heart repair with a special focus on the anticipated modes of action of tissue-engineered therapy candidates and particular implications as to transplant immunology. Myocardial tissue engineering technologies have made tremendous advances in recent years. Numerous different strategies are under investigation and have reached different stages on their way to clinical translation. Studies in animal models demonstrated that heart repair requires either remuscularization by delivery of bona fide cardiomyocytes or paracrine support for the activation of endogenous repair mechanisms. Tissue engineering approaches result in enhanced cardiomyocyte retention and sustained remuscularization, but may also be explored for targeted paracrine or mechanical support. Some of the more advanced tissue engineering approaches are already tested clinically; others are at late stages of pre-clinical development. Process optimization towards cGMP compatibility and clinical scalability of contractile engineered human myocardium is an essential step towards clinical translation. Long-term allograft retention can be achieved under immune suppression. HLA matching may be an option to enhance graft retention and reduce the need for comprehensive immune suppression. Tissue-engineered heart repair is entering the clinical stage of the translational pipeline. Like in any effective therapy, side effects must be anticipated and carefully controlled. Allograft implantation under immune suppression is the most likely clinical scenario. Strategies to overcome transplant rejection are evolving and may further boost the clinical acceptance of tissue-engineered heart repair.

Engineering organs.

PubMed

Atala, Anthony

2009-10-01

Applications of regenerative medicine technology may offer novel therapies for patients with injuries, end-stage organ failure, or other clinical problems. Currently, patients suffering from diseased and injured organs can be treated with transplanted organs. However, there is a severe shortage of donor organs that is worsening yearly as the population ages and new cases of organ failure increase. Scientists in the field of regenerative medicine and tissue engineering are now applying the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. The stem cell field is also advancing rapidly, opening new avenues for this type of therapy. For example, therapeutic cloning and cellular reprogramming may one day provide a potentially limitless source of cells for tissue engineering applications. Although stem cells are still in the research phase, some therapies arising from tissue engineering endeavors have already entered the clinical setting successfully, indicating the promise regenerative medicine holds for the future.

Using Acellular Bioactive Extracellular Matrix Scaffolds to Enhance Endogenous Cardiac Repair

PubMed Central

Svystonyuk, Daniyil A.; Mewhort, Holly E. M.; Fedak, Paul W. M.

2018-01-01

An inability to recover lost cardiac muscle following acute ischemic injury remains the biggest shortcoming of current therapies to prevent heart failure. As compared to standard medical and surgical treatments, tissue engineering strategies offer the promise of improved heart function by inducing regeneration of functional heart muscle. Tissue engineering approaches that use stem cells and genetic manipulation have shown promise in preclinical studies but have also been challenged by numerous critical barriers preventing effective clinical translational. We believe that surgical intervention using acellular bioactive ECM scaffolds may yield similar therapeutic benefits with minimal translational hurdles. In this review, we outline the limitations of cellular-based tissue engineering strategies and the advantages of using acellular biomaterials with bioinductive properties. We highlight key anatomic targets enriched with cellular niches that can be uniquely activated using bioactive scaffold therapy. Finally, we review the evolving cardiovascular tissue engineering landscape and provide critical insights into the potential therapeutic benefits of acellular scaffold therapy. PMID:29696148

Non-genetic engineering of cells for drug delivery and cell-based therapy.

PubMed

Wang, Qun; Cheng, Hao; Peng, Haisheng; Zhou, Hao; Li, Peter Y; Langer, Robert

2015-08-30

Cell-based therapy is a promising modality to address many unmet medical needs. In addition to genetic engineering, material-based, biochemical, and physical science-based approaches have emerged as novel approaches to modify cells. Non-genetic engineering of cells has been applied in delivering therapeutics to tissues, homing of cells to the bone marrow or inflammatory tissues, cancer imaging, immunotherapy, and remotely controlling cellular functions. This new strategy has unique advantages in disease therapy and is complementary to existing gene-based cell engineering approaches. A better understanding of cellular systems and different engineering methods will allow us to better exploit engineered cells in biomedicine. Here, we review non-genetic cell engineering techniques and applications of engineered cells, discuss the pros and cons of different methods, and provide our perspectives on future research directions. Copyright © 2014 Elsevier B.V. All rights reserved.

Stem cell homing-based tissue engineering using bioactive materials

NASA Astrophysics Data System (ADS)

Yu, Yinxian; Sun, Binbin; Yi, Chengqing; Mo, Xiumei

2017-06-01

Tissue engineering focuses on repairing tissue and restoring tissue functions by employing three elements: scaffolds, cells and biochemical signals. In tissue engineering, bioactive material scaffolds have been used to cure tissue and organ defects with stem cell-based therapies being one of the best documented approaches. In the review, different biomaterials which are used in several methods to fabricate tissue engineering scaffolds were explained and show good properties (biocompatibility, biodegradability, and mechanical properties etc.) for cell migration and infiltration. Stem cell homing is a recruitment process for inducing the migration of the systemically transplanted cells, or host cells, to defect sites. The mechanisms and modes of stem cell homing-based tissue engineering can be divided into two types depending on the source of the stem cells: endogenous and exogenous. Exogenous stem cell-based bioactive scaffolds have the challenge of long-term culturing in vitro and for endogenous stem cells the biochemical signal homing recruitment mechanism is not clear yet. Although the stem cell homing-based bioactive scaffolds are attractive candidates for tissue defect therapies, based on in vitro studies and animal tests, there is still a long way before clinical application.

Stem Cells for Cardiac Regeneration by Cell Therapy and Myocardial Tissue Engineering

NASA Astrophysics Data System (ADS)

Wu, Jun; Zeng, Faquan; Weisel, Richard D.; Li, Ren-Ke

Congestive heart failure, which often occurs progressively following a myocardial infarction, is characterized by impaired myocardial perfusion, ventricular dilatation, and cardiac dysfunction. Novel treatments are required to reverse these effects - especially in older patients whose endogenous regenerative responses to currently available therapies are limited by age. This review explores the current state of research for two related approaches to cardiac regeneration: cell therapy and tissue engineering. First, to evaluate cell therapy, we review the effectiveness of various cell types for their ability to limit ventricular dilatation and promote functional recovery following implantation into a damaged heart. Next, to assess tissue engineering, we discuss the characteristics of several biomaterials for their potential to physically support the infarcted myocardium and promote implanted cell survival following cardiac injury. Finally, looking ahead, we present recent findings suggesting that hybrid constructs combining a biomaterial with stem and supporting cells may be the most effective approaches to cardiac regeneration.

Tissue engineering for lateral ridge augmentation with recombinant human bone morphogenetic protein 2 combination therapy: a case report.

PubMed

Mandelaris, George A; Spagnoli, Daniel B; Rosenfeld, Alan L; McKee, James; Lu, Mei

2015-01-01

This case report describes a tissue-engineered reconstruction with recombinant human bone morphogenetic protein 2/acellular collagen sponge (rhBMP-2/ ACS) + cancellous allograft and space maintenance via Medpor Contain mesh in the treatment of a patient requiring maxillary and mandibular horizontal ridge augmentation to enable implant placement. The patient underwent a previously unsuccessful corticocancellous bone graft at these sites. Multiple and contiguous sites in the maxilla and in the mandibular anterior, demonstrating advanced lateral ridge deficiencies, were managed using a tissue engineering approach as an alternative to autogenous bone harvesting. Four maxillary and three mandibular implants were placed 9 and 10 months, respectively, after tissue engineering reconstruction, and all were functioning successfully after 24 months of follow-up. Histomorphometric analysis of a bone core obtained at the time of the maxillary implant placement demonstrated a mean of 76.1% new vital bone formation, 22.2% marrow/cells, and 1.7% residual graft tissue. Tissue engineering for lateral ridge augmentation with combination therapy requires further research to determine predictability and limitations.

Tissue engineering: current strategies and future directions.

PubMed

Olson, Jennifer L; Atala, Anthony; Yoo, James J

2011-04-01

Novel therapies resulting from regenerative medicine and tissue engineering technology may offer new hope for patients with injuries, end-stage organ failure, or other clinical issues. Currently, patients with diseased and injured organs are often treated with transplanted organs. However, there is a shortage of donor organs that is worsening yearly as the population ages and as the number of new cases of organ failure increases. Scientists in the field of regenerative medicine and tissue engineering are now applying the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that can restore and maintain normal function in diseased and injured tissues. In addition, the stem cell field is a rapidly advancing part of regenerative medicine, and new discoveries in this field create new options for this type of therapy. For example, new types of stem cells, such as amniotic fluid and placental stem cells that can circumvent the ethical issues associated with embryonic stem cells, have been discovered. The process of therapeutic cloning and the creation of induced pluripotent cells provide still other potential sources of stem cells for cell-based tissue engineering applications. Although stem cells are still in the research phase, some therapies arising from tissue engineering endeavors that make use of autologous, adult cells have already entered the clinical setting, indicating that regenerative medicine holds much promise for the future.

Cartilage tissue engineering: recent advances and perspectives from gene regulation/therapy.

PubMed

Li, Kuei-Chang; Hu, Yu-Chen

2015-05-01

Diseases in articular cartilages affect millions of people. Despite the relatively simple biochemical and cellular composition of articular cartilages, the self-repair ability of cartilage is limited. Successful cartilage tissue engineering requires intricately coordinated interactions between matrerials, cells, biological factors, and phycial/mechanical factors, and still faces a multitude of challenges. This article presents an overview of the cartilage biology, current treatments, recent advances in the materials, biological factors, and cells used in cartilage tissue engineering/regeneration, with strong emphasis on the perspectives of gene regulation (e.g., microRNA) and gene therapy. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bone tissue engineering: state of the art and future trends.

PubMed

Salgado, António J; Coutinho, Olga P; Reis, Rui L

2004-08-09

Although several major progresses have been introduced in the field of bone regenerative medicine during the years, current therapies, such as bone grafts, still have many limitations. Moreover, and in spite of the fact that material science technology has resulted in clear improvements in the field of bone substitution medicine, no adequate bone substitute has been developed and hence large bone defects/injuries still represent a major challenge for orthopaedic and reconstructive surgeons. It is in this context that TE has been emerging as a valid approach to the current therapies for bone regeneration/substitution. In contrast to classic biomaterial approach, TE is based on the understanding of tissue formation and regeneration, and aims to induce new functional tissues, rather than just to implant new spare parts. The present review pretends to give an exhaustive overview on all components needed for making bone tissue engineering a successful therapy. It begins by giving the reader a brief background on bone biology, followed by an exhaustive description of all the relevant components on bone TE, going from materials to scaffolds and from cells to tissue engineering strategies, that will lead to "engineered" bone. Scaffolds processed by using a methodology based on extrusion with blowing agents.

Two-photon induced collagen cross-linking in bioartificial cardiac tissue

NASA Astrophysics Data System (ADS)

Kuetemeyer, Kai; Kensah, George; Heidrich, Marko; Meyer, Heiko; Martin, Ulrich; Gruh, Ina; Heisterkamp, Alexander

2011-08-01

Cardiac tissue engineering is a promising strategy for regenerative therapies to overcome the shortage of donor organs for transplantation. Besides contractile function, the stiffness of tissue engineered constructs is crucial to generate transplantable tissue surrogates with sufficient mechanical stability to withstand the high pressure present in the heart. Although several collagen cross-linking techniques have proven to be efficient in stabilizing biomaterials, they cannot be applied to cardiac tissue engineering, as cell death occurs in the treated area. Here, we present a novel method using femtosecond (fs) laser pulses to increase the stiffness of collagen-based tissue constructs without impairing cell viability. Raster scanning of the fs laser beam over riboflavin-treated tissue induced collagen cross-linking by two-photon photosensitized singlet oxygen production. One day post-irradiation, stress-strain measurements revealed increased tissue stiffness by around 40% being dependent on the fibroblast content in the tissue. At the same time, cells remained viable and fully functional as demonstrated by fluorescence imaging of cardiomyocyte mitochondrial activity and preservation of active contraction force. Our results indicate that two-photon induced collagen cross-linking has great potential for studying and improving artificially engineered tissue for regenerative therapies.

Tissue engineering and regenerative medicine in applied research: a year in review of 2014.

PubMed

Lin, Xunxun; Huang, Jia; Shi, Yuan; Liu, Wei

2015-04-01

Tissue engineering and regenerative medicine (TERM) remains to be one of the fastest growing fields, which covers a wide scope of topics of both basic and applied biological researches. This overview article summarized the advancements in applied researches of TERM area, including stem cell-mediated tissue regeneration, material science, and TERM clinical trial. These achievements demonstrated the great potential of clinical regenerative therapy of tissue/organ disease or defect through stem cells and tissue engineering approaches.

Tissue engineering in dentistry.

PubMed

Abou Neel, Ensanya Ali; Chrzanowski, Wojciech; Salih, Vehid M; Kim, Hae-Won; Knowles, Jonathan C

2014-08-01

of this review is to inform practitioners with the most updated information on tissue engineering and its potential applications in dentistry. The authors used "PUBMED" to find relevant literature written in English and published from the beginning of tissue engineering until today. A combination of keywords was used as the search terms e.g., "tissue engineering", "approaches", "strategies" "dentistry", "dental stem cells", "dentino-pulp complex", "guided tissue regeneration", "whole tooth", "TMJ", "condyle", "salivary glands", and "oral mucosa". Abstracts and full text articles were used to identify causes of craniofacial tissue loss, different approaches for craniofacial reconstructions, how the tissue engineering emerges, different strategies of tissue engineering, biomaterials employed for this purpose, the major attempts to engineer different dental structures, finally challenges and future of tissue engineering in dentistry. Only those articles that dealt with the tissue engineering in dentistry were selected. There have been a recent surge in guided tissue engineering methods to manage periodontal diseases beyond the traditional approaches. However, the predictable reconstruction of the innate organisation and function of whole teeth as well as their periodontal structures remains challenging. Despite some limited progress and minor successes, there remain distinct and important challenges in the development of reproducible and clinically safe approaches for oral tissue repair and regeneration. Clearly, there is a convincing body of evidence which confirms the need for this type of treatment, and public health data worldwide indicates a more than adequate patient resource. The future of these therapies involving more biological approaches and the use of dental tissue stem cells is promising and advancing. Also there may be a significant interest of their application and wider potential to treat disorders beyond the craniofacial region. Considering the interests of the patients who could possibly be helped by applying stem cell-based therapies should be carefully assessed against current ethical concerns regarding the moral status of the early embryo. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Tissue engineering therapies for the vocal fold lamina propria.

PubMed

Kutty, Jaishankar K; Webb, Ken

2009-09-01

The vocal folds are laryngeal connective tissues with complex matrix composition/organization that provide the viscoelastic mechanical properties required for voice production. Vocal fold injury results in alterations in tissue structure and corresponding changes in tissue biomechanics that reduce vocal quality. Recent work has begun to elucidate the biochemical changes underlying injury-induced pathology and to apply tissue engineering principles to the prevention and reversal of vocal fold scarring. Based on the extensive history of injectable biomaterials in laryngeal surgery, a major focus of regenerative therapies has been the development of novel scaffolds with controlled in vivo residence time and viscoelastic properties approximating the native tissue. Additional strategies have included cell transplantation and delivery of the antifibrotic cytokine hepatocyte growth factor, as well as investigation of the effects of the unique vocal fold vibratory microenvironment using in vitro dynamic culture systems. Recent achievements of significant reductions in fibrosis and improved recovery of native tissue viscoelasticity and vibratory/functional performance in animal models are rapidly moving vocal fold tissue engineering toward clinical application.

Engineering Lubrication in Articular Cartilage

PubMed Central

McNary, Sean M.; Athanasiou, Kyriacos A.

2012-01-01

Despite continuous progress toward tissue engineering of functional articular cartilage, significant challenges still remain. Advances in morphogens, stem cells, and scaffolds have resulted in enhancement of the bulk mechanical properties of engineered constructs, but little attention has been paid to the surface mechanical properties. In the near future, engineered tissues will be able to withstand and support the physiological compressive and tensile forces in weight-bearing synovial joints such as the knee. However, there is an increasing realization that these tissue-engineered cartilage constructs will fail without the optimal frictional and wear properties present in native articular cartilage. These characteristics are critical to smooth, pain-free joint articulation and a long-lasting, durable cartilage surface. To achieve optimal tribological properties, engineered cartilage therapies will need to incorporate approaches and methods for functional lubrication. Steady progress in cartilage lubrication in native tissues has pushed the pendulum and warranted a shift in the articular cartilage tissue-engineering paradigm. Engineered tissues should be designed and developed to possess both tribological and mechanical properties mirroring natural cartilage. In this article, an overview of the biology and engineering of articular cartilage structure and cartilage lubrication will be presented. Salient progress in lubrication treatments such as tribosupplementation, pharmacological, and cell-based therapies will be covered. Finally, frictional assays such as the pin-on-disk tribometer will be addressed. Knowledge related to the elements of cartilage lubrication has progressed and, thus, an opportune moment is provided to leverage these advances at a critical step in the development of mechanically and tribologically robust, biomimetic tissue-engineered cartilage. This article is intended to serve as the first stepping stone toward future studies in functional tissue engineering of articular cartilage that begins to explore and incorporate methods of lubrication. PMID:21955119

21 CFR 5.1100 - Headquarters.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Laboratories Complex Staff. Division of Engineering Services. Environment, Safety And Strategic Initiatives.... Office of Cellular, Tissue, and Gene Therapies. Regulatory Management Staff. Division of Cellular and Gene Therapies. Division of Clinical Evaluation and Pharmacology/Toxicology. Division of Human Tissues...

The Use of Mathematical Modelling for Improving the Tissue Engineering of Organs and Stem Cell Therapy.

PubMed

Lemon, Greg; Sjoqvist, Sebastian; Lim, Mei Ling; Feliu, Neus; Firsova, Alexandra B; Amin, Risul; Gustafsson, Ylva; Stuewer, Annika; Gubareva, Elena; Haag, Johannes; Jungebluth, Philipp; Macchiarini, Paolo

2016-01-01

Regenerative medicine is a multidisciplinary field where continued progress relies on the incorporation of a diverse set of technologies from a wide range of disciplines within medicine, science and engineering. This review describes how one such technique, mathematical modelling, can be utilised to improve the tissue engineering of organs and stem cell therapy. Several case studies, taken from research carried out by our group, ACTREM, demonstrate the utility of mechanistic mathematical models to help aid the design and optimisation of protocols in regenerative medicine.

Emerging Roles for Extracellular Vesicles in Tissue Engineering and Regenerative Medicine

PubMed Central

Lamichhane, Tek N.; Sokic, Sonja; Schardt, John S.; Raiker, Rahul S.; Lin, Jennifer W.

2015-01-01

Extracellular vesicles (EVs)—comprising a heterogeneous population of cell-derived lipid vesicles including exosomes, microvesicles, and others—have recently emerged as both mediators of intercellular information transfer in numerous biological systems and vehicles for drug delivery. In both roles, EVs have immense potential to impact tissue engineering and regenerative medicine applications. For example, the therapeutic effects of several progenitor and stem cell-based therapies have been attributed primarily to EVs secreted by these cells, and EVs have been recently reported to play direct roles in injury-induced tissue regeneration processes in multiple physiological systems. In addition, EVs have been utilized for targeted drug delivery in regenerative applications and possess unique potential to be harnessed as patient-derived drug delivery vehicles for personalized medicine. This review discusses EVs in the context of tissue repair and regeneration, including their utilization as drug carriers and their crucial role in cell-based therapies. Furthermore, the article highlights the growing need for bioengineers to understand, consider, and ultimately design and specifically control the activity of EVs to maximize the efficacy of tissue engineering and regenerative therapies. PMID:24957510

Periosteum tissue engineering-a review.

PubMed

Li, Nanying; Song, Juqing; Zhu, Guanglin; Li, Xiaoyu; Liu, Lei; Shi, Xuetao; Wang, Yingjun

2016-10-18

As always, the clinical therapy of critical size bone defects caused by trauma, tumor removal surgery or congenital malformation is facing great challenges. Currently, various approaches including autograft, allograft and cell-biomaterial composite based tissue-engineering strategies have been implemented to reconstruct injured bone. However, due to damage during the transplantation processes or design negligence of the bionic scaffolds, these methods expose vulnerabilities without the assistance of periosteum, a bilayer membrane on the outer surface of the bone. Periosteum plays a significant role in bone formation and regeneration as a store for progenitor cells, a source of local growth factors and a scaffold to recruit cells and growth factors, and more and more researchers have recognized its great value in tissue engineering application. Besides direct transplantation, periosteum-derived cells can be cultured on various scaffolds for osteogenesis or chondrogenesis application due to their availability. Research studies also provide a biomimetic methodology to synthesize artificial periosteum which mimic native periosteum in structure or function. According to the studies, these tissue-engineered periostea did obviously enhance the therapeutic effects of bone graft and scaffold engineering while they could be directly used as substitutes of native periosteum. Periosteum tissue engineering, whose related research studies have provided new opportunities for the development of bone tissue engineering and therapy, has gradually become a hot spot and there are still lots to consummate. In this review, tissue-engineered periostea were classified into four kinds and discussed, which might help subsequent researchers get a more systematic view of pseudo-periosteum.

The role of nanotechnology in induced pluripotent and embryonic stem cells research.

PubMed

Chen, Lukui; Qiu, Rong; Li, Lushen

2014-12-01

This paper reviews the recent studies on development of nanotechnology in the field of induced pluripotent and embryonic stem cells. Stem cell therapy is a promising therapy that can improve the quality of life for patients with refractory diseases. However, this option is limited by the scarcity of tissues, ethical problem, and tumorigenicity. Nanotechnology is another promising therapy that can be used to mimic the extracellular matrix, label the implanted cells, and also can be applied in the tissue engineering. In this review, we briefly introduce implementation of nanotechnology in induced pluripotent and embryonic stem cells research. Finally, the potential application of nanotechnology in tissue engineering and regenerative medicine is also discussed.

Tissue engineering in urothelium regeneration.

PubMed

Vaegler, Martin; Maurer, Sabine; Toomey, Patricia; Amend, Bastian; Sievert, Karl-Dietrich

2015-03-01

The development of therapeutic treatments to regenerate urothelium, manufacture tissue equivalents or neourethras for in-vivo application is a significant challenge in the field of tissue engineering. Many studies have focused on urethral defects that, in most cases, inadequately address current therapies. This article reviews the primary tissue engineering strategies aimed at the clinical requirements for urothelium regeneration while concentrating on promising investigations in the use of grafts, cellular preparations, as well as seeded or unseeded natural and synthetic materials. Despite significant progress being made in the development of scaffolds and matrices, buccal mucosa transplants have not been replaced. Recently, graft tissues appear to have an advantage over the use of matrices. These therapies depend on cell isolation and propagation in vitro that require, not only substantial laboratory resources, but also subsequent surgical implant procedures. The choice of the correct cell source is crucial when determining an in-vivo application because of the risks of tissue changes and abnormalities that may result in donor site morbidity. Addressing an appropriately-designed animal model and relevant regulatory issues is of fundamental importance for the principal investigators when a therapy using cellular components has been developed for clinical use. Copyright © 2014 Elsevier B.V. All rights reserved.

Tissue engineering and cell-based therapy toward integrated strategy with artificial organs.

PubMed

Gojo, Satoshi; Toyoda, Masashi; Umezawa, Akihiro

2011-09-01

Research in order that artificial organs can supplement or completely replace the functions of impaired or damaged tissues and internal organs has been underway for many years. The recent clinical development of implantable left ventricular assist devices has revolutionized the treatment of patients with heart failure. The emerging field of regenerative medicine, which uses human cells and tissues to regenerate internal organs, is now advancing from basic and clinical research to clinical application. In this review, we focus on the novel biomaterials, i.e., fusion protein, and approaches such as three-dimensional and whole-organ tissue engineering. We also compare induced pluripotent stem cells, directly reprogrammed cardiomyocytes, and somatic stem cells for cell source of future cell-based therapy. Integrated strategy of artificial organ and tissue engineering/regenerative medicine should give rise to a new era of medical treatment to organ failure.

Cell and Tissue Engineering for Liver Disease

PubMed Central

Bhatia, Sangeeta N.; Underhill, Gregory H.; Zaret, Kenneth S.; Fox, Ira J.

2015-01-01

Despite the tremendous hurdles presented by the complexity of the liver’s structure and function, advances in liver physiology, stem cell biology and reprogramming, and the engineering of tissues and devices are accelerating the development of cell-based therapies for treating liver disease and liver failure. This State of the Art Review discusses both the near and long-term prospects for such cell-based therapies and the unique challenges for clinical translation. PMID:25031271

The potential of nanofibers in tissue engineering and stem cell therapy.

PubMed

Gholizadeh-Ghaleh Aziz, Shiva; Gholizadeh-Ghaleh Aziz, Sara; Akbarzadeh, Abolfazl

2016-08-01

Electrospinning is a technique in which materials in solution are shaped into continuous nano- and micro-sized fibers. Combining stem cells with biomaterial scaffolds and nanofibers affords a favorable approach for bone tissue engineering, stem cell growth and transfer, ocular surface reconstruction, and treatment of congenital corneal diseases. This review seeks to describe the current examples of the use of scaffolds in stem cell therapy. Stem cells are classified as adult or embryonic stem (ES) cells, and the advantages and drawbacks of each group are detailed. The nanofibers and scaffolds are further classified in Tables I and II , which describe specific examples from the literature. Finally, the current applications of biomaterial scaffolds containing stem cells for tissue engineering applications are presented. Overall, this review seeks to give an overview of the biomaterials available for use in combination with stem cells, and the application of nanofibers in stem cell therapy.

Piezoelectric polymers as biomaterials for tissue engineering applications.

PubMed

Ribeiro, Clarisse; Sencadas, Vítor; Correia, Daniela M; Lanceros-Méndez, Senentxu

2015-12-01

Tissue engineering often rely on scaffolds for supporting cell differentiation and growth. Novel paradigms for tissue engineering include the need of active or smart scaffolds in order to properly regenerate specific tissues. In particular, as electrical and electromechanical clues are among the most relevant ones in determining tissue functionality in tissues such as muscle and bone, among others, electroactive materials and, in particular, piezoelectric ones, show strong potential for novel tissue engineering strategies, in particular taking also into account the existence of these phenomena within some specific tissues, indicating their requirement also during tissue regeneration. This referee reports on piezoelectric materials used for tissue engineering applications. The most used materials for tissue engineering strategies are reported together with the main achievements, challenges and future needs for research and actual therapies. This review provides thus a compilation of the most relevant results and strategies and a start point for novel research pathways in the most relevant and challenging open questions. Copyright © 2015 Elsevier B.V. All rights reserved.

Clinical Application of Stem Cells in the Cardiovascular System

NASA Astrophysics Data System (ADS)

Stamm, Christof; Klose, Kristin; Choi, Yeong-Hoon

Regenerative medicine encompasses "tissue engineering" - the in vitro fabrication of tissues and/or organs using scaffold material and viable cells - and "cell therapy" - the transplantation or manipulation of cells in diseased tissue in vivo. In the cardiovascular system, tissue engineering strategies are being pursued for the development of viable replacement blood vessels, heart valves, patch material, cardiac pacemakers and contractile myocardium. Anecdotal clinical applications of such vessels, valves and patches have been described, but information on systematic studies of the performance of such implants is not available, yet. Cell therapy for cardiovascular regeneration, however, has been performed in large series of patients, and numerous clinical studies have produced sometimes conflicting results. The purpose of this chapter is to summarize the clinical experience with cell therapy for diseases of the cardiovascular system, and to analyse possible factors that may influence its outcome.

The early career researcher's toolkit: translating tissue engineering, regenerative medicine and cell therapy products.

PubMed

Rafiq, Qasim A; Ortega, Ilida; Jenkins, Stuart I; Wilson, Samantha L; Patel, Asha K; Barnes, Amanda L; Adams, Christopher F; Delcassian, Derfogail; Smith, David

2015-11-01

Although the importance of translation for the development of tissue engineering, regenerative medicine and cell-based therapies is widely recognized, the process of translation is less well understood. This is particularly the case among some early career researchers who may not appreciate the intricacies of translational research or make decisions early in development which later hinders effective translation. Based on our own research and experiences as early career researchers involved in tissue engineering and regenerative medicine translation, we discuss common pitfalls associated with translational research, providing practical solutions and important considerations which will aid process and product development. Suggestions range from effective project management, consideration of key manufacturing, clinical and regulatory matters and means of exploiting research for successful commercialization.

Application of Disposable Bag Bioreactors in Tissue Engineering and for the Production of Therapeutic Agents

NASA Astrophysics Data System (ADS)

Eibl, R.; Eibl, D.

In order to increase process efficiency, many pharmaceutical and biotechnology companies have introduced disposable bag technology over the last 10 years. Because this technology also greatly reduces the risk of cross-contamination, disposable bags are preferred in applications in which an absolute or improved process safety is a necessity, namely the production of functional tissue for implantation (tissue engineering), the production of human cells for the treatment of cancer and immune system diseases (cellular therapy), the production of viruses for gene therapies, the production of therapeutic proteins, and veterinary as well as human vaccines.

Therapeutic cloning and tissue engineering.

PubMed

Koh, Chester J; Atala, Anthony

2004-01-01

A severe shortage of donor organs available for transplantation in the United States leaves patients suffering from diseased and injured organs with few treatment options. Scientists in the field of tissue engineering apply the principles of cell transplantation, material science, and engineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The present chapter reviews recent advances that have occurred in therapeutic cloning and tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

Current Therapeutic Strategies for Adipose Tissue Defects/Repair Using Engineered Biomaterials and Biomolecule Formulations.

PubMed

Mahoney, Christopher M; Imbarlina, Cayla; Yates, Cecelia C; Marra, Kacey G

2018-01-01

Tissue engineered scaffolds for adipose restoration/repair has significantly evolved in recent years. Patients requiring soft tissue reconstruction, caused by defects or pathology, require biomaterials that will restore void volume with new functional tissue. The gold standard of autologous fat grafting (AFG) is not a reliable option. This review focuses on the latest therapeutic strategies for the treatment of adipose tissue defects using biomolecule formulations and delivery, and specifically engineered biomaterials. Additionally, the clinical need for reliable off-the-shelf therapies, animal models, and challenges facing current technologies are discussed.

Effects of mechanical loading on human mesenchymal stem cells for cartilage tissue engineering.

PubMed

Choi, Jane Ru; Yong, Kar Wey; Choi, Jean Yu

2018-03-01

Today, articular cartilage damage is a major health problem, affecting people of all ages. The existing conventional articular cartilage repair techniques, such as autologous chondrocyte implantation (ACI), microfracture, and mosaicplasty, have many shortcomings which negatively affect their clinical outcomes. Therefore, it is essential to develop an alternative and efficient articular repair technique that can address those shortcomings. Cartilage tissue engineering, which aims to create a tissue-engineered cartilage derived from human mesenchymal stem cells (MSCs), shows great promise for improving articular cartilage defect therapy. However, the use of tissue-engineered cartilage for the clinical therapy of articular cartilage defect still remains challenging. Despite the importance of mechanical loading to create a functional cartilage has been well demonstrated, the specific type of mechanical loading and its optimal loading regime is still under investigation. This review summarizes the most recent advances in the effects of mechanical loading on human MSCs. First, the existing conventional articular repair techniques and their shortcomings are highlighted. The important parameters for the evaluation of the tissue-engineered cartilage, including chondrogenic and hypertrophic differentiation of human MSCs are briefly discussed. The influence of mechanical loading on human MSCs is subsequently reviewed and the possible mechanotransduction signaling is highlighted. The development of non-hypertrophic chondrogenesis in response to the changing mechanical microenvironment will aid in the establishment of a tissue-engineered cartilage for efficient articular cartilage repair. © 2017 Wiley Periodicals, Inc.

Mechanical Stimulation of Adipose-Derived Stem Cells for Functional Tissue Engineering of the Musculoskeletal System via Cyclic Hydrostatic Pressure, Simulated Microgravity, and Cyclic Tensile Strain.

PubMed

Nordberg, Rachel C; Bodle, Josie C; Loboa, Elizabeth G

2018-01-01

It is critical that human adipose stem cell (hASC) tissue-engineering therapies possess appropriate mechanical properties in order to restore function of the load bearing tissues of the musculoskeletal system. In an effort to elucidate the hASC response to mechanical stimulation and develop mechanically robust tissue engineered constructs, recent research has utilized a variety of mechanical loading paradigms including cyclic tensile strain, cyclic hydrostatic pressure, and mechanical unloading in simulated microgravity. This chapter describes methods for applying these mechanical stimuli to hASC to direct differentiation for functional tissue engineering of the musculoskeletal system.

Challenges in Cardiac Tissue Engineering

PubMed Central

Tandon, Nina; Godier, Amandine; Maidhof, Robert; Marsano, Anna; Martens, Timothy P.; Radisic, Milica

2010-01-01

Cardiac tissue engineering aims to create functional tissue constructs that can reestablish the structure and function of injured myocardium. Engineered constructs can also serve as high-fidelity models for studies of cardiac development and disease. In a general case, the biological potential of the cell—the actual “tissue engineer”—is mobilized by providing highly controllable three-dimensional environments that can mediate cell differentiation and functional assembly. For cardiac regeneration, some of the key requirements that need to be met are the selection of a human cell source, establishment of cardiac tissue matrix, electromechanical cell coupling, robust and stable contractile function, and functional vascularization. We review here the potential and challenges of cardiac tissue engineering for developing therapies that could prevent or reverse heart failure. PMID:19698068

Periodontics--tissue engineering and the future.

PubMed

Douglass, Gordon L

2005-03-01

Periodontics has a long history of utilizing advances in science to expand and improve periodontal therapies. Recently the American Academy of Periodontology published the findings of the Contemporary Science Workshop, which conducted state-of-the-art evidence-based reviews of current and emerging areas in periodontics. The findings of this workshop provide the basis for an evidence-based approach to periodontal therapy. While the workshop evaluated all areas of periodontics, it is in the area of tissue engineering that the most exciting advances are becoming a reality.

Tissue engineering and regenerative medicine: concepts for clinical application.

PubMed

Atala, Anthony

2004-01-01

Patients suffering from diseased and injured organs may be treated with transplanted organs. However, there is a severe shortage of donor organs that is worsening yearly given the aging population. Scientists in the field of regenerative medicine and tissue engineering apply the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy. This paper reviews recent advances that have occurred in regenerative medicine and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

Engineering tissues, organs and cells.

PubMed

Atala, Anthony

2007-01-01

Patients suffering from diseased and injured organs may be treated with transplanted organs; however, there is a severe shortage of donor organs that is worsening yearly, given the ageing population. In the field of regenerative medicine and tissue engineering, scientists apply the principles of cell transplantation, materials science and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy, including the use of amniotic and placental fetal stem cells. This review covers recent advances that have occurred in regenerative medicine and describes applications of these technologies using chemical compounds that may offer novel therapies for patients with end-stage organ failure. 2007 John Wiley & Sons, Ltd

Tissue engineering of ligaments for reconstructive surgery.

PubMed

Hogan, MaCalus V; Kawakami, Yohei; Murawski, Christopher D; Fu, Freddie H

2015-05-01

The use of musculoskeletal bioengineering and regenerative medicine applications in orthopaedic surgery has continued to evolve. The aim of this systematic review was to address tissue-engineering strategies for knee ligament reconstruction. A systematic review of PubMed/Medline using the terms "knee AND ligament" AND "tissue engineering" OR "regenerative medicine" was performed. Two authors performed the search, independently assessed the studies for inclusion, and extracted the data for inclusion in the review. Both preclinical and clinical studies were reviewed, and the articles deemed most relevant were included in this article to provide relevant basic science and recent clinical translational knowledge concerning "tissue-engineering" strategies currently used in knee ligament reconstruction. A total of 224 articles were reviewed in our initial PubMed search. Non-English-language studies were excluded. Clinical and preclinical studies were identified, and those with a focus on knee ligament tissue-engineering strategies including stem cell-based therapies, growth factor administration, hybrid biomaterial, and scaffold development, as well as mechanical stimulation modalities, were reviewed. The body of knowledge surrounding tissue-engineering strategies for ligament reconstruction continues to expand. Presently, various tissue-engineering techniques have some potential advantages, including faster recovery, better ligamentization, and possibly, a reduction of recurrence. Preclinical research of these novel therapies continues to provide promising results. There remains a need for well-designed, high-powered comparative clinical studies to serve as a foundation for successful translation into the clinical setting going forward. Level IV, systematic review of Level IV studies. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Customized biomaterials to augment chondrocyte gene therapy.

PubMed

Aguilar, Izath Nizeet; Trippel, Stephen; Shi, Shuiliang; Bonassar, Lawrence J

2017-04-15

A persistent challenge in enhancing gene therapy is the transient availability of the target gene product. This is particularly true in tissue engineering applications. The transient exposure of cells to the product could be insufficient to promote tissue regeneration. Here we report the development of a new material engineered to have a high affinity for a therapeutic gene product. We focus on insulin-like growth factor-I (IGF-I) for its highly anabolic effects on many tissues such as spinal cord, heart, brain and cartilage. One of the ways that tissues store IGF-I is through a group of insulin like growth factor binding proteins (IGFBPs), such as IGFBP-5. We grafted the IGF-I binding peptide sequence from IGFBP-5 onto alginate in order to retain the endogenous IGF-I produced by transfected chondrocytes. This novel material bound IGF-I and released the growth factor for at least 30days in culture. We found that this binding enhanced the biosynthesis of transfected cells up to 19-fold. These data demonstrate the coordinated engineering of cell behavior and material chemistry to greatly enhance extracellular matrix synthesis and tissue assembly, and can serve as a template for the enhanced performance of other therapeutic proteins. The present manuscript focuses on the enhancement of chondrocyte gene therapy through the modification of scaffold materials to enhance the retention of targeted gene products. This study combined tissue engineering and gene therapy, where customized biomaterials augmented the action of IGF-I by enhancing the retention of protein produced by transfection of the IGF-I gene. This approach enabled tuning of binding of IGF-I to alginate, which increased GAG and HYPRO production by transfected chondrocytes. To our knowledge, peptide-based modification of materials to augment growth factor-targeted gene therapy has not been reported previously. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Towards autotrophic tissue engineering: Photosynthetic gene therapy for regeneration.

PubMed

Chávez, Myra Noemi; Schenck, Thilo Ludwig; Hopfner, Ursula; Centeno-Cerdas, Carolina; Somlai-Schweiger, Ian; Schwarz, Christian; Machens, Hans-Günther; Heikenwalder, Mathias; Bono, María Rosa; Allende, Miguel L; Nickelsen, Jörg; Egaña, José Tomás

2016-01-01

The use of artificial tissues in regenerative medicine is limited due to hypoxia. As a strategy to overcome this drawback, we have shown that photosynthetic biomaterials can produce and provide oxygen independently of blood perfusion by generating chimeric animal-plant tissues during dermal regeneration. In this work, we demonstrate the safety and efficacy of photosynthetic biomaterials in vivo after engraftment in a fully immunocompetent mouse skin defect model. Further, we show that it is also possible to genetically engineer such photosynthetic scaffolds to deliver other key molecules in addition to oxygen. As a proof-of-concept, biomaterials were loaded with gene modified microalgae expressing the angiogenic recombinant protein VEGF. Survival of the algae, growth factor delivery and regenerative potential were evaluated in vitro and in vivo. This work proposes the use of photosynthetic gene therapy in regenerative medicine and provides scientific evidence for the use of engineered microalgae as an alternative to deliver recombinant molecules for gene therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

A bird's-eye view of cell therapy and tissue engineering for cardiac regeneration.

PubMed

Soler-Botija, Carolina; Bagó, Juli R; Bayes-Genis, Antoni

2012-04-01

Complete recovery of ischemic cardiac muscle after myocardial infarction is still an unresolved concern. In recent years, intensive research efforts have focused on mimicking the physical and biological properties of myocardium for cardiac repair. Here we show how heart regeneration approaches have evolved from cell therapy to refined tissue engineering. Despite progressive improvements, the best cell type and delivery strategy are not well established. Our group has identified a new population of cardiac adipose tissue-derived progenitor cells with inherent cardiac and angiogenic potential that is a promising candidate for cell therapy to restore ischemic myocardium. We also describe results from three strategies for cell delivery into a murine model of myocardial infarction: intramyocardial injection, implantation of a fibrin patch loaded with cells, and an engineered bioimplant (a combination of chemically designed scaffold, peptide hydrogel, and cells); dual-labeling noninvasive bioluminescence imaging enables in vivo monitoring of cardiac-specific markers and cell survival. © 2012 New York Academy of Sciences.

Physical non-viral gene delivery methods for tissue engineering.

PubMed

Mellott, Adam J; Forrest, M Laird; Detamore, Michael S

2013-03-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that "fits-all" cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications.

Physical non-viral gene delivery methods for tissue engineering

PubMed Central

Mellott, Adam J.; Forrest, M. Laird; Detamore, Michael S.

2016-01-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that “fits-all” cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications. PMID:23099792

Cutting-edge platforms in cardiac tissue engineering.

PubMed

Fleischer, Sharon; Feiner, Ron; Dvir, Tal

2017-10-01

As cardiac disease takes a higher toll with each passing year, the need for new therapies to deal with the scarcity in heart donors becomes ever more pressing. Cardiac tissue engineering holds the promise of creating functional replacement tissues to repair heart tissue damage. In an attempt to bridge the gap between the lab and clinical realization, the field has made major strides. In this review, we will discuss state of the art technologies such as layer-by-layer assembly, bioprinting and bionic tissue engineering, all developed to overcome some of the major hurdles faced in the field. Copyright © 2017 Elsevier Ltd. All rights reserved.

Periodontal tissue engineering strategies based on nonoral stem cells.

PubMed

Requicha, João Filipe; Viegas, Carlos Alberto; Muñoz, Fernando; Reis, Rui Luís; Gomes, Manuela Estima

2014-01-01

Periodontal disease is an inflammatory disease which constitutes an important health problem in humans due to its enormous prevalence and life threatening implications on systemic health. Routine standard periodontal treatments include gingival flaps, root planning, application of growth/differentiation factors or filler materials and guided tissue regeneration. However, these treatments have come short on achieving regeneration ad integrum of the periodontium, mainly due to the presence of tissues from different embryonic origins and their complex interactions along the regenerative process. Tissue engineering (TE) aims to regenerate damaged tissue by providing the repair site with a suitable scaffold seeded with sufficient undifferentiated cells and, thus, constitutes a valuable alternative to current therapies for the treatment of periodontal defects. Stem cells from oral and dental origin are known to have potential to regenerate these tissues. Nevertheless, harvesting cells from these sites implies a significant local tissue morbidity and low cell yield, as compared to other anatomical sources of adult multipotent stem cells. This manuscript reviews studies describing the use of non-oral stem cells in tissue engineering strategies, highlighting the importance and potential of these alternative stem cells sources in the development of advanced therapies for periodontal regeneration. Copyright © 2013 Wiley Periodicals, Inc.

Tissue-Engineering Approaches to Restore Kidney Function.

PubMed

Katari, Ravi; Edgar, Lauren; Wong, Theresa; Boey, Angela; Mancone, Sarah; Igel, Daniel; Callese, Tyler; Voigt, Marcia; Tamburrini, Riccardo; Zambon, Joao Paulo; Perin, Laura; Orlando, Giuseppe

2015-10-01

Kidney transplantation for the treatment of chronic kidney disease has established outcome and quality of life. However, its implementation is severely limited by a chronic shortage of donor organs; consequently, most candidates remain on dialysis and on the waiting list while accruing further morbidity and mortality. Furthermore, those patients that do receive kidney transplants are committed to a life-long regimen of immunosuppressive drugs that also carry significant adverse risk profiles. The disciplines of tissue engineering and regenerative medicine have the potential to produce alternative therapies which circumvent the obstacles posed by organ shortage and immunorejection. This review paper describes some of the most promising tissue-engineering solutions currently under investigation for the treatment of acute and chronic kidney diseases. The various stem cell therapies, whole embryo transplantation, and bioengineering with ECM scaffolds are outlined and summarized.

Comparative study of chitosan and chitosan-gelatin scaffold for tissue engineering

NASA Astrophysics Data System (ADS)

Kumar, Pawan; Dehiya, Brijnandan S.; Sindhu, Anil

2017-12-01

A number of orthopedic disorders and bone defect issues are solved by scaffold-based therapy in tissue engineering. The biocompatibility of chitosan (polysaccharide) and its similarity with glycosaminoglycan makes it a bone-grafting material. The current work focus on the synthesis of chitosan and chitosan-gelatin scaffold for hard tissue engineering. The chitosan and chitosan-gelatin scaffold have shown improved specific surface area, density, porosity, mechanical properties, biodegradability and absorption. These scaffolds can lead to the development or artificial fabrication of hard tissue alternates. The porous scaffold samples were prepared by freeze-drying method. The microstructure, mechanical and degradable properties of chitosan and chitosan-gelatin scaffolds were analyzed and results revealed that the scaffolds prepared from chitosan-gelatin can be utilized as a useful matrix for tissue engineering.

Articular cartilage tissue engineering with plasma-rich in growth factors and stem cells with nano scaffolds

NASA Astrophysics Data System (ADS)

Montaser, Laila M.; Abbassy, Hadeer A.; Fawzy, Sherin M.

2016-09-01

The ability to heal soft tissue injuries and regenerate cartilage is the Holy Grail of musculoskeletal medicine. Articular cartilage repair and regeneration is considered to be largely intractable due to the poor regenerative properties of this tissue. Due to their low self-repair ability, cartilage defects that result from joint injury, aging, or osteoarthritis, are the most often irreversible and are a major cause of joint pain and chronic disability. However, current methods do not perfectly restore hyaline cartilage and may lead to the apparition of fibro- or continue hypertrophic cartilage. The lack of efficient modalities of treatment has prompted research into tissue engineering combining stem cells, scaffold materials and environmental factors. The field of articular cartilage tissue engineering, which aims to repair, regenerate, and/or improve injured or diseased cartilage functionality, has evoked intense interest and holds great potential for improving cartilage therapy. Plasma-rich in growth factors (PRGF) and/or stem cells may be effective for tissue repair as well as cartilage regenerative processes. There is a great promise to advance current cartilage therapies toward achieving a consistently successful approach for addressing cartilage afflictions. Tissue engineering may be the best way to reach this objective via the use of stem cells, novel biologically inspired scaffolds and, emerging nanotechnology. In this paper, current and emergent approach in the field of cartilage tissue engineering is presented for specific application. In the next years, the development of new strategies using stem cells, in scaffolds, with supplementation of culture medium could improve the quality of new formed cartilage.

Craniofacial Tissue Engineering by Stem Cells

PubMed Central

Mao, J.J.; Giannobile, W.V.; Helms, J.A.; Hollister, S.J.; Krebsbach, P.H.; Longaker, M.T.; Shi, S.

2008-01-01

Craniofacial tissue engineering promises the regeneration or de novo formation of dental, oral, and craniofacial structures lost to congenital anomalies, trauma, and diseases. Virtually all craniofacial structures are derivatives of mesenchymal cells. Mesenchymal stem cells are the offspring of mesenchymal cells following asymmetrical division, and reside in various craniofacial structures in the adult. Cells with characteristics of adult stem cells have been isolated from the dental pulp, the deciduous tooth, and the periodontium. Several craniofacial structures—such as the mandibular condyle, calvarial bone, cranial suture, and subcutaneous adipose tissue—have been engineered from mesenchymal stem cells, growth factor, and/or gene therapy approaches. As a departure from the reliance of current clinical practice on durable materials such as amalgam, composites, and metallic alloys, biological therapies utilize mesenchymal stem cells, delivered or internally recruited, to generate craniofacial structures in temporary scaffolding biomaterials. Craniofacial tissue engineering is likely to be realized in the foreseeable future, and represents an opportunity that dentistry cannot afford to miss. PMID:17062735

Nano-regenerative medicine towards clinical outcome of stem cell and tissue engineering in humans

PubMed Central

Arora, Pooja; Sindhu, Annu; Dilbaghi, Neeraj; Chaudhury, Ashok; Rajakumar, Govindasamy; Rahuman, Abdul Abdul

2012-01-01

Nanotechnology is a fast growing area of research that aims to create nanomaterials or nanostructures development in stem cell and tissue-based therapies. Concepts and discoveries from the fields of bio nano research provide exciting opportunities of using stem cells for regeneration of tissues and organs. The application of nanotechnology to stem-cell biology would be able to address the challenges of disease therapeutics. This review covers the potential of nanotechnology approaches towards regenerative medicine. Furthermore, it focuses on current aspects of stem- and tissue-cell engineering. The magnetic nanoparticles-based applications in stem-cell research open new frontiers in cell and tissue engineering. PMID:22260258

Biomechanical properties of the spinal cord: implications for tissue engineering and clinical translation.

PubMed

Bartlett, Richard D; Choi, David; Phillips, James B

2016-10-01

Spinal cord injury is a severely debilitating condition which can leave individuals paralyzed and suffering from autonomic dysfunction. Regenerative medicine may offer a promising solution to this problem. Previous research has focused primarily on exploring the cellular and biological aspects of the spinal cord, yet relatively little remains known about the biomechanical properties of spinal cord tissue. Given that a number of regenerative strategies aim to deliver cells and materials in the form of tissue-engineered therapies, understanding the biomechanical properties of host spinal cord tissue is important. We review the relevant biomechanical properties of spinal cord tissue and provide the baseline knowledge required to apply these important physical concepts to spinal cord tissue engineering.

Recent progresses in gene delivery-based bone tissue engineering.

PubMed

Lu, Chia-Hsin; Chang, Yu-Han; Lin, Shih-Yeh; Li, Kuei-Chang; Hu, Yu-Chen

2013-12-01

Gene therapy has converged with bone engineering over the past decade, by which a variety of therapeutic genes have been delivered to stimulate bone repair. These genes can be administered via in vivo or ex vivo approach using either viral or nonviral vectors. This article reviews the fundamental aspects and recent progresses in the gene therapy-based bone engineering, with emphasis on the new genes, viral vectors and gene delivery approaches. © 2013.

Genetic engineering for skeletal regenerative medicine.

PubMed

Gersbach, Charles A; Phillips, Jennifer E; García, Andrés J

2007-01-01

The clinical challenges of skeletal regenerative medicine have motivated significant advances in cellular and tissue engineering in recent years. In particular, advances in molecular biology have provided the tools necessary for the design of gene-based strategies for skeletal tissue repair. Consequently, genetic engineering has emerged as a promising method to address the need for sustained and robust cellular differentiation and extracellular matrix production. As a result, gene therapy has been established as a conventional approach to enhance cellular activities for skeletal tissue repair. Recent literature clearly demonstrates that genetic engineering is a principal factor in constructing effective methods for tissue engineering approaches to bone, cartilage, and connective tissue regeneration. This review highlights this literature, including advances in the development of efficacious gene carriers, novel cell sources, successful delivery strategies, and optimal target genes. The current status of the field and the challenges impeding the clinical realization of these approaches are also discussed.

An exploratory survey on the views of European tissue engineers concerning the ethical issues of tissue engineering research.

PubMed

Trommelmans, Leen; Selling, Joseph; Dierickx, Kris

2009-09-01

We present the first exploratory survey about the views of tissue engineers on the ethical issues of tissue engineering (TE), conducted among participants of a large European TE consortium. We analyzed the topics for which ethical guidance is necessary and the preferred dissemination channels, which are relevant issues and goals of clinical trials with human tissue-engineered products, and which information is to be given to trial participants. The need for comprehensive, specific ethical guidance of TE is a first key finding of this survey. Second, it becomes clear that little clarity exists on some crucial issues in the setup and conduct of clinical trials in TE. Identifying the unique features of TE and their repercussions for the ethical conduct of TE research and therapy is necessary. Third, prospective trial participants are to be informed about a wide variety of issues before taking part in the trial.

Cardiovascular tissue engineering: where we come from and where are we now?

PubMed

Smit, Francis E; Dohmen, Pascal M

2015-01-27

Abstract Tissue engineering was introduced by Vacanti and Langer in the 80's, exploring the potential of this new technology starting with the well-known "human ear on the mouse back". The goal is to create a substitute which supplies an individual therapy for patients with regeneration, remodeling and growth potential. The growth potential of these subjects is of special interest in congenital cardiac surgery, avoiding repeated interventions and surgery. Initial applications of tissue engineered created substitutes were relatively simple cardiovascular grafts seeded initially by end-differentiated autologous endothelial cells. Important data were collected from these initial clinical autologous endothelial cell seeded grafts in peripheral and coronary vessel disease. After these initial successfully implantation bone marrow cell were used to seed patches and pulmonary conduits were implanted in patients. Driven by the positive results of tissue engineered material implanted under low pressure circumstances, first tissue engineered patches were implanted in the systemic circulation followed by the implantation of tissue engineered aortic heart valves. Tissue engineering is an extreme dynamic technology with continuously modifications and improvements to optimize clinical products. New technologies are unified and so this has also be done with tissue engineering and new application features, so called transcatheter valve intervention. First studies are initiated to apply tissue engineered heart valves with this new transcatheter delivery system less invasive. Simultaneously studies have been started on tissue engineering of so-called whole organs since organ transplantation is restricted due to donor shortage and tissue engineering could overcome this problem. Initial studies of whole heart engineering in the rat model are promising and larger size models are initiated.

Review paper: critical issues in tissue engineering: biomaterials, cell sources, angiogenesis, and drug delivery systems.

PubMed

Naderi, Hojjat; Matin, Maryam M; Bahrami, Ahmad Reza

2011-11-01

Tissue engineering is a newly emerging biomedical technology, which aids and increases the repair and regeneration of deficient and injured tissues. It employs the principles from the fields of materials science, cell biology, transplantation, and engineering in an effort to treat or replace damaged tissues. Tissue engineering and development of complex tissues or organs, such as heart, muscle, kidney, liver, and lung, are still a distant milestone in twenty-first century. Generally, there are four main challenges in tissue engineering which need optimization. These include biomaterials, cell sources, vascularization of engineered tissues, and design of drug delivery systems. Biomaterials and cell sources should be specific for the engineering of each tissue or organ. On the other hand, angiogenesis is required not only for the treatment of a variety of ischemic conditions, but it is also a critical component of virtually all tissue-engineering strategies. Therefore, controlling the dose, location, and duration of releasing angiogenic factors via polymeric delivery systems, in order to ultimately better mimic the stem cell niche through scaffolds, will dictate the utility of a variety of biomaterials in tissue regeneration. This review focuses on the use of polymeric vehicles that are made of synthetic and/or natural biomaterials as scaffolds for three-dimensional cell cultures and for locally delivering the inductive growth factors in various formats to provide a method of controlled, localized delivery for the desired time frame and for vascularized tissue-engineering therapies.

Cartilage tissue engineering: From biomaterials and stem cells to osteoarthritis treatments.

PubMed

Vinatier, C; Guicheux, J

2016-06-01

Articular cartilage is a non-vascularized and poorly cellularized connective tissue that is frequently damaged as a result of trauma and degenerative joint diseases such as osteoarthrtis. Because of the absence of vascularization, articular cartilage has low capacity for spontaneous repair. Today, and despite a large number of preclinical data, no therapy capable of restoring the healthy structure and function of damaged articular cartilage is clinically available. Tissue-engineering strategies involving the combination of cells, scaffolding biomaterials and bioactive agents have been of interest notably for the repair of damaged articular cartilage. During the last 30 years, cartilage tissue engineering has evolved from the treatment of focal lesions of articular cartilage to the development of strategies targeting the osteoarthritis process. In this review, we focus on the different aspects of tissue engineering applied to cartilage engineering. We first discuss cells, biomaterials and biological or environmental factors instrumental to the development of cartilage tissue engineering, then review the potential development of cartilage engineering strategies targeting new emerging pathogenic mechanisms of osteoarthritis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Engineering blood vessels by gene and cell therapy.

PubMed

Zarbiv, Gabriel; Preis, Meir; Ben-Yosef, Yaara; Flugelman, Moshe Y

2007-08-01

Cardiovascular-related syndromes are the leading cause of morbidity and mortality worldwide. Arterial narrowing and blockage due to atherosclerosis cause reduced blood flow to the brain, heart and legs. Bypass surgery to improve blood flow to the heart and legs in these patients is performed in hundreds of thousands of patients every year. Autologous grafts, such as the internal thoracic artery and saphenous vein, are used in most patients, but in a significant number of patients such grafts are not available and synthetic grafts are used. Synthetic grafts have higher failure rates than autologous grafts due to thrombosis and scar formation within graft lumen. Cell and gene therapy combined with tissue engineering hold a great promise to provide grafts that will be biocompatible and durable. This review describes the field of vascular grafts in the context of tissue engineering using cell and gene therapies.

Genetic engineering of mesenchymal stem cells and its application in human disease therapy.

PubMed

Hodgkinson, Conrad P; Gomez, José A; Mirotsou, Maria; Dzau, Victor J

2010-11-01

The use of stem cells for tissue regeneration and repair is advancing both at the bench and bedside. Stem cells isolated from bone marrow are currently being tested for their therapeutic potential in a variety of clinical conditions including cardiovascular injury, kidney failure, cancer, and neurological and bone disorders. Despite the advantages, stem cell therapy is still limited by low survival, engraftment, and homing to damage area as well as inefficiencies in differentiating into fully functional tissues. Genetic engineering of mesenchymal stem cells is being explored as a means to circumvent some of these problems. This review presents the current understanding of the use of genetically engineered mesenchymal stem cells in human disease therapy with emphasis on genetic modifications aimed to improve survival, homing, angiogenesis, and heart function after myocardial infarction. Advancements in other disease areas are also discussed.

Strategies to Maximize the Potential of Marine Biomaterials as a Platform for Cell Therapy

PubMed Central

Kim, Hyeongmin; Lee, Jaehwi

2016-01-01

Marine biopolymers have been explored as a promising cell therapy system for efficient cell delivery and tissue engineering. However, the marine biomaterial-based systems themselves have exhibited limited performance in terms of maintenance of cell viability and functions, promotion of cell proliferation and differentiation as well as cell delivery efficiency. Thus, numerous novel strategies have been devised to improve cell therapy outcomes. The strategies include optimization of physical and biochemical properties, provision of stimuli-responsive functions, and design of platforms for efficient cell delivery and tissue engineering. These approaches have demonstrated substantial improvement of therapeutic outcomes in a variety of research settings. In this review, therefore, research progress made with marine biomaterials as a platform for cell therapy is reported along with current research directions to further advance cell therapies as a tool to cure incurable diseases. PMID:26821034

Regenerative dentistry: translating advancements in basic science research to the dental practice.

PubMed

Garcia-Godoy, Franklin; Murray, Peter

2010-01-01

Scientific advances in the creation of restorative biomaterials, in vitro cell culture technology, tissue engineering, molecular biology and the human genome project provide the basis for the introduction of new technologies into dentistry. This review provides an assessment of how tissue engineering, stem cell, genetic transfer, biomaterial and growth factor therapies can be integrated into clinical dental therapies to restore and regenerate oral tissues. In parallel to the creation of a new field in general medicine called "regenerative medicine," we call this field "regenerative dentistry." While the problems of introducing regenerative therapies are substantial, the potential benefits to patients and the profession are equally ground-breaking. In this review, we outline a few areas of interest for the future of oral and dental medicine in which advancements in basic science have already been adapted to fit the goals of 21st century dentistry.

The Impact of Biomechanics in Tissue Engineering and Regenerative Medicine

PubMed Central

Butler, David L.; Goldstein, Steven A.; Guo, X. Edward; Kamm, Roger; Laurencin, Cato T.; McIntire, Larry V.; Mow, Van C.; Nerem, Robert M.; Sah, Robert L.; Soslowsky, Louis J.; Spilker, Robert L.; Tranquillo, Robert T.

2009-01-01

Biomechanical factors profoundly influence the processes of tissue growth, development, maintenance, degeneration, and repair. Regenerative strategies to restore damaged or diseased tissues in vivo and create living tissue replacements in vitro have recently begun to harness advances in understanding of how cells and tissues sense and adapt to their mechanical environment. It is clear that biomechanical considerations will be fundamental to the successful development of clinical therapies based on principles of tissue engineering and regenerative medicine for a broad range of musculoskeletal, cardiovascular, craniofacial, skin, urinary, and neural tissues. Biomechanical stimuli may in fact hold the key to producing regenerated tissues with high strength and endurance. However, many challenges remain, particularly for tissues that function within complex and demanding mechanical environments in vivo. This paper reviews the present role and potential impact of experimental and computational biomechanics in engineering functional tissues using several illustrative examples of past successes and future grand challenges. PMID:19583462

3D Bioprinting Technologies for Hard Tissue and Organ Engineering

PubMed Central

Wang, Xiaohong; Ao, Qiang; Tian, Xiaohong; Fan, Jun; Wei, Yujun; Hou, Weijian; Tong, Hao; Bai, Shuling

2016-01-01

Hard tissues and organs, including the bones, teeth and cartilage, are the most extensively exploited and rapidly developed areas in regenerative medicine field. One prominent character of hard tissues and organs is that their extracellular matrices mineralize to withstand weight and pressure. Over the last two decades, a wide variety of 3D printing technologies have been adapted to hard tissue and organ engineering. These 3D printing technologies have been defined as 3D bioprinting. Especially for hard organ regeneration, a series of new theories, strategies and protocols have been proposed. Some of the technologies have been applied in medical therapies with some successes. Each of the technologies has pros and cons in hard tissue and organ engineering. In this review, we summarize the advantages and disadvantages of the historical available innovative 3D bioprinting technologies for used as special tools for hard tissue and organ engineering. PMID:28773924

3D Bioprinting Technologies for Hard Tissue and Organ Engineering.

PubMed

Wang, Xiaohong; Ao, Qiang; Tian, Xiaohong; Fan, Jun; Wei, Yujun; Hou, Weijian; Tong, Hao; Bai, Shuling

2016-09-27

Hard tissues and organs, including the bones, teeth and cartilage, are the most extensively exploited and rapidly developed areas in regenerative medicine field. One prominent character of hard tissues and organs is that their extracellular matrices mineralize to withstand weight and pressure. Over the last two decades, a wide variety of 3D printing technologies have been adapted to hard tissue and organ engineering. These 3D printing technologies have been defined as 3D bioprinting. Especially for hard organ regeneration, a series of new theories, strategies and protocols have been proposed. Some of the technologies have been applied in medical therapies with some successes. Each of the technologies has pros and cons in hard tissue and organ engineering. In this review, we summarize the advantages and disadvantages of the historical available innovative 3D bioprinting technologies for used as special tools for hard tissue and organ engineering.

77 FR 61004 - Request for Nominations for Voting Members on Public Advisory Committees

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-05

...--individuals knowledgeable in tissue engineering/regenerative medicine, orthopedic oncology. [[Page 61005... Committee, Cellular, Tissue and Gene Therapies Advisory Committee, and Transmissible Spongiform and... . Advisory Committee. Gail Dapolito, Center for Biologics Cellular, Tissue and Gene Evaluation and Research...

A tetracycline expression system in combination with Sox9 for cartilage tissue engineering.

PubMed

Yao, Yi; He, Yu; Guan, Qian; Wu, Qiong

2014-02-01

Cartilage tissue engineering using controllable transcriptional therapy together with synthetic biopolymer scaffolds shows higher potential for overcoming chondrocyte degradation and constructing artificial cartilages both in vivo and in vitro. Here, the potential regulating tetracycline expression (Tet-on) system was used to express Sox9 both in vivo and in vitro. Chondrocyte degradation was measured in vitro and overcome by Soxf9 expression. Experiments confirmed the feasibility of the combined use of Sox9 and Tet-on system in cartilage tissue engineering. Engineered poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds were seeded with recombinant chondrocytes which were transfected with Tet-induced Sox9 expression; the scaffolds were implanted under the skin of 8-week-old rats. The experimental group was injected with Dox in the abdomen, while the control group was injected with normal saline. After 4 or 8 days of implantation in vivo, the newly formed pieces of articular chondrocytes were taken out and measured. Dox injection in vivo showed positive effect on recombinant chondrocytes, in which Sox9 expression was up-regulated by an inducible system with specific matrix proteins. The results demonstrate this controllable transcriptional therapy is a potential approach for tissue engineering. Copyright © 2013 Elsevier Ltd. All rights reserved.

Current Approaches to Bone Tissue Engineering: The Interface between Biology and Engineering.

PubMed

Li, Jiao Jiao; Ebied, Mohamed; Xu, Jen; Zreiqat, Hala

2018-03-01

The successful regeneration of bone tissue to replace areas of bone loss in large defects or at load-bearing sites remains a significant clinical challenge. Over the past few decades, major progress is achieved in the field of bone tissue engineering to provide alternative therapies, particularly through approaches that are at the interface of biology and engineering. To satisfy the diverse regenerative requirements of bone tissue, the field moves toward highly integrated approaches incorporating the knowledge and techniques from multiple disciplines, and typically involves the use of biomaterials as an essential element for supporting or inducing bone regeneration. This review summarizes the types of approaches currently used in bone tissue engineering, beginning with those primarily based on biology or engineering, and moving into integrated approaches in the areas of biomaterial developments, biomimetic design, and scalable methods for treating large or load-bearing bone defects, while highlighting potential areas for collaboration and providing an outlook on future developments. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tissue engineering of reproductive tissues and organs.

PubMed

Atala, Anthony

2012-07-01

Regenerative medicine and tissue engineering technology may soon offer new hope for patients with serious injuries and end-stage reproductive organ failure. Scientists are now applying the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that can restore and maintain normal function in diseased and injured reproductive tissues. In addition, the stem cell field is advancing, and new discoveries in this field will lead to new therapeutic strategies. For example, newly discovered types of stem cells have been retrieved from uterine tissues such as amniotic fluid and placental stem cells. The process of therapeutic cloning and the creation of induced pluripotent cells provide still other potential sources of stem cells for cell-based tissue engineering applications. Although stem cells are still in the research phase, some therapies arising from tissue engineering endeavors that make use of autologous adult cells have already entered the clinic. This article discusses these tissue engineering strategies for various organs in the male and female reproductive tract. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Enhanced Intracellular Delivery and Tissue Retention of Nanoparticles by Mussel-Inspired Surface Chemistry.

PubMed

Chen, Kai; Xu, Xiaoqiu; Guo, Jiawei; Zhang, Xuelin; Han, Songling; Wang, Ruibing; Li, Xiaohui; Zhang, Jianxiang

2015-11-09

Nanomaterials have been broadly studied for intracellular delivery of diverse compounds for diagnosis or therapy. Currently it remains challenging for discovering new biomolecules that can prominently enhance cellular internalization and tissue retention of nanoparticles (NPs). Herein we report for the first time that a mussel-inspired engineering approach may notably promote cellular uptake and tissue retention of NPs. In this strategy, the catechol moiety is covalently anchored onto biodegradable NPs. Thus, fabricated NPs can be more effectively internalized by sensitive and multidrug resistant tumor cells, as well as some normal cells, resulting in remarkably potentiated in vitro activity when an antitumor drug is packaged. Moreover, the newly engineered NPs afford increased tissue retention post local or oral delivery. This biomimetic approach is promising for creating functional nanomaterials for drug delivery, vaccination, and cell therapy.

Integrated approaches to spatiotemporally directing angiogenesis in host and engineered tissues.

PubMed

Kant, Rajeev J; Coulombe, Kareen L K

2018-03-15

The field of tissue engineering has turned towards biomimicry to solve the problem of tissue oxygenation and nutrient/waste exchange through the development of vasculature. Induction of angiogenesis and subsequent development of a vascular bed in engineered tissues is actively being pursued through combinations of physical and chemical cues, notably through the presentation of topographies and growth factors. Presenting angiogenic signals in a spatiotemporal fashion is beginning to generate improved vascular networks, which will allow for the creation of large and dense engineered tissues. This review provides a brief background on the cells, mechanisms, and molecules driving vascular development (including angiogenesis), followed by how biomaterials and growth factors can be used to direct vessel formation and maturation. Techniques to accomplish spatiotemporal control of vascularization include incorporation or encapsulation of growth factors, topographical engineering, and 3D bioprinting. The vascularization of engineered tissues and their application in angiogenic therapy in vivo is reviewed herein with an emphasis on the most densely vascularized tissue of the human body - the heart. Vascularization is vital to wound healing and tissue regeneration, and development of hierarchical networks enables efficient nutrient transfer. In tissue engineering, vascularization is necessary to support physiologically dense engineered tissues, and thus the field seeks to induce vascular formation using biomaterials and chemical signals to provide appropriate, pro-angiogenic signals for cells. This review critically examines the materials and techniques used to generate scaffolds with spatiotemporal cues to direct vascularization in engineered and host tissues in vitro and in vivo. Assessment of the field's progress is intended to inspire vascular applications across all forms of tissue engineering with a specific focus on highlighting the nuances of cardiac tissue engineering for the greater regenerative medicine community. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Allograft integration in a rabbit transgenic model for anterior cruciate ligament reconstruction.

PubMed

Bachy, M; Sherifi, I; Zadegan, F; Petite, H; Vialle, R; Hannouche, D

2016-04-01

Tissue engineering strategies include both cell-based and cell homing therapies. Ligamentous tissues are highly specialized and constitute vital components of the musculoskeletal system. Their damage causes significant morbidity and loss in function. The aim of this study is to analyze tendinous graft integration, cell repopulation and ligamentization by using GFP+/- allografts in GFP+/- transgenic New Zealand white (NZW) rabbits. Graft implantation was designed to closely mimic anterior cruciate ligament (ACL) repair surgery. Allografts were implanted in 8 NZW rabbits and assessed at 5 days, 3 weeks and 6 weeks through: (1) arthroCT imaging, (2) morphological analysis of the transplanted allograft, (3) histological analysis, (4) collagen type I immunochemistry, and (5) GFP cell tracking. Collagen remodeling was appreciated at 3 and 6 weeks. Graft repopulation with host cells, chondrocyte-like cells at the tendon-bone interface and graft corticalization in the bone tunnels were noticed at 3 weeks. By contrast we noticed a central necrosis aspect in the allografts intra-articularly at 6 weeks with a cell migration towards the graft edge near the synovium. Our study has served to gain a better understanding of tendinous allograft bone integration, ligamentization and allograft repopulation. We believe that both cell-based therapies and cell homing therapies are beneficial in ligament tissue engineering. Future studies may elucidate whether cell repopulation occurs with pre-differentiated or progenitor cells. We believe that both cell-based therapies and cell homing therapies are beneficial in ligament tissue engineering. Level V (animal study). Copyright © 2015 Elsevier Masson SAS. All rights reserved.

How Can Nanotechnology Help to Repair the Body? Advances in Cardiac, Skin, Bone, Cartilage and Nerve Tissue Regeneration

PubMed Central

Perán, Macarena; García, María Angel; Lopez-Ruiz, Elena; Jiménez, Gema; Marchal, Juan Antonio

2013-01-01

Nanotechnologists have become involved in regenerative medicine via creation of biomaterials and nanostructures with potential clinical implications. Their aim is to develop systems that can mimic, reinforce or even create in vivo tissue repair strategies. In fact, in the last decade, important advances in the field of tissue engineering, cell therapy and cell delivery have already been achieved. In this review, we will delve into the latest research advances and discuss whether cell and/or tissue repair devices are a possibility. Focusing on the application of nanotechnology in tissue engineering research, this review highlights recent advances in the application of nano-engineered scaffolds designed to replace or restore the followed tissues: (i) skin; (ii) cartilage; (iii) bone; (iv) nerve; and (v) cardiac. PMID:28809213

Induced Pluripotent Stem Cells and Periodontal Regeneration.

PubMed

Du, Mi; Duan, Xuejing; Yang, Pishan

Periodontitis is a chronic inflammatory disease which leads to destruction of both the soft and hard tissues of the periodontium. Tissue engineering is a therapeutic approach in regenerative medicine that aims to induce new functional tissue regeneration via the synergistic combination of cells, biomaterials, and/or growth factors. Advances in our understanding of the biology of stem cells, including embryonic stem cells and mesenchymal stem cells, have provided opportunities for periodontal tissue engineering. However, there remain a number of limitations affecting their therapeutic efficiency. Due to the considerable proliferation and differentiation capacities, recently described induced pluripotent stem cells (iPSCs) provide a new way for cell-based therapies for periodontal regeneration. This review outlines the latest status of periodontal tissue engineering and highlights the potential use of iPSCs in periodontal tissue regeneration.

Engineering a clinically-useful matrix for cell therapy.

PubMed

Prestwich, Glenn D

2008-01-01

The design criteria for matrices for encapsulation of cells for cell therapy include chemical, biological, engineering, marketing, regulatory, and financial constraints. What is required is a biocompatible material for culture of cells in three-dimensions (3-D) that offers ease of use, experimental flexibility to alter composition and compliance, and a composition that would permit a seamless transition from in vitro to in vivo use. The challenge is to replicate the complexity of the native extracellular matrix (ECM) environment with the minimum number of components necessary to allow cells to rebuild a given tissue. Our approach is to deconstruct the ECM to a few modular components that can be reassembled into biomimetic materials that meet these criteria. These semi-synthetic ECMs (sECMs) employ thiol-modified derivatives of hyaluronic acid (HA) that can form covalently crosslinked, biodegradable hydrogels. These sECMs are "living" biopolymers, meaning that they can be crosslinked in the presence of cells or tissues to enable cell therapy and tissue engineering. Moreover, the sECMs allow inclusion of the appropriate biological cues needed to simulate the complexity of the ECM of a given tissue. Taken together, the sECM technology offers a manufacturable, highly reproducible, flexible, FDA-approvable, and affordable vehicle for cell expansion and differentiation in 3-D.

The Crosstalk between Tissue Engineering and Pharmaceutical Biotechnology: Recent Advances and Future Directions.

PubMed

Pacheco, Daniela P; Reis, Rui L; Correlo, Vítor M; Marques, Alexandra P

2015-01-01

Tissue-engineered constructs made of biotechnology-derived materials have been preferred due to their chemical and physical composition, which offers both high versatility and a support to enclose/ incorporate relevant signaling molecules and/or genes known to therapeutically induce tissue repair. Herein, a critical overview of the impact of different biotechnology-derived materials, scaffolds, and recombinant signaling molecules over the behavior of cells, another element of tissue engineered constructs, as well its regulatory role in tissue regeneration and disease progression is given. Additionally, these tissue-engineered constructs evolved to three-dimensional (3D) tissue-like models that, as an advancement of two-dimensional standard culture methods, are expected to be a valuable tool in the field of drug discovery and pharmaceutical research. Despite the improved design and conception of current proposed 3D tissue-like models, advanced control systems to enable and accelerate streamlining and automation of the numerous labor-intensive steps intrinsic to the development of tissue-engineered constructs are still to be achieved. In this sense, this review intends to present the biotechnology- derived materials that are being explored in the field of tissue engineering to generate 3D tissue-analogues and briefly highlight their foremost breakthroughs in tissue regeneration and drug discovery. It also aims to reinforce that the crosstalk between tissue engineering and pharmaceutical biotechnology has been fostering the outcomes of tissue engineering approaches through the use of biotechnology-derived signaling molecules. Gene delivery/therapy is also discussed as a forefront area that represents another cross point between tissue engineering and pharmaceutical biotechnology, in which nucleic acids can be considered a "super pharmaceutical" to drive biological responses, including tissue regeneration.

Bone tissue engineering using silica-based mesoporous nanobiomaterials:Recent progress.

PubMed

Shadjou, Nasrin; Hasanzadeh, Mohammad

2015-10-01

Bone disorders are of significant concern due to increase in the median age of our population. It is in this context that tissue engineering has been emerging as a valid approach to the current therapies for bone regeneration/substitution. Tissue-engineered bone constructs have the potential to alleviate the demand arising from the shortage of suitable autograft and allograft materials for augmenting bone healing. Silica based mesostructured nanomaterials possessing pore sizes in the range 2-50 nm and surface reactive functionalities have elicited immense interest due to their exciting prospects in bone tissue engineering. In this review we describe application of silica-based mesoporous nanomaterials for bone tissue engineering. We summarize the preparation methods, the effect of mesopore templates and composition on the mesopore-structure characteristics, and different forms of these materials, including particles, fibers, spheres, scaffolds and composites. Also, the effect of structural and textural properties of mesoporous materials on development of new biomaterials for production of bone implants and bone cements was discussed. Also, application of different mesoporous materials on construction of manufacture 3-dimensional scaffolds for bone tissue engineering was discussed. It begins by giving the reader a brief background on tissue engineering, followed by a comprehensive description of all the relevant components of silica-based mesoporous biomaterials on bone tissue engineering, going from materials to scaffolds and from cells to tissue engineering strategies that will lead to "engineered" bone. Copyright © 2015 Elsevier B.V. All rights reserved.

Therapeutic cloning applications for organ transplantation.

PubMed

Koh, Chester J; Atala, Anthony

2004-04-01

A severe shortage of donor organs available for transplantation in the United States leaves patients suffering from diseased and injured organs with few treatment options. Scientists in the field of tissue engineering apply the principles of cell transplantation, material science, and engineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The present chapter reviews recent advances that have occurred in therapeutic cloning and tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure. Copyright 2004 Elsevier B.V.

Site-Specific Genome Engineering in Human Pluripotent Stem Cells.

PubMed

Merkert, Sylvia; Martin, Ulrich

2016-06-24

The possibility to generate patient-specific induced pluripotent stem cells (iPSCs) offers an unprecedented potential of applications in clinical therapy and medical research. Human iPSCs and their differentiated derivatives are tools for diseases modelling, drug discovery, safety pharmacology, and toxicology. Moreover, they allow for the engineering of bioartificial tissue and are promising candidates for cellular therapies. For many of these applications, the ability to genetically modify pluripotent stem cells (PSCs) is indispensable, but efficient site-specific and safe technologies for genetic engineering of PSCs were developed only recently. By now, customized engineered nucleases provide excellent tools for targeted genome editing, opening new perspectives for biomedical research and cellular therapies.

Extraction and Assembly of Tissue-Derived Gels for Cell Culture and Tissue Engineering

PubMed Central

Uriel, Shiri; Labay, Edwardine; Francis-Sedlak, Megan; Moya, Monica L.; Weichselbaum, Ralph R.; Ervin, Natalia; Cankova, Zdravka

2009-01-01

Interactions with the extracellular matrix (ECM) play an important role in regulating cell function. Cells cultured in, or on, three-dimensional ECM recapitulate similar features to those found in vivo that are not present in traditional two-dimensional culture. In addition, both natural and synthetic materials containing ECM components have shown promise in a number of tissue engineering applications. Current materials available for cell culture and tissue engineering do not adequately reflect the diversity of ECM composition between tissues. In this paper, a method is presented for extracting solutions of proteins and glycoproteins from soft tissues and inducing assembly of these proteins into gels. The extracts contain ECM proteins specific to the tissue source with low levels of intracellular molecules. Gels formed from the tissue-derived extracts have nanostructure similar to ECM in vivo and can be used to culture cells as both a thin substrate coating and a thick gel. This technique could be used to assemble hydrogels with varying composition depending upon the tissue source, hydrogels for three-dimensional culture, as scaffolds for tissue engineering therapies, and to study cell–matrix interactions. PMID:19115821

[Reconstruction of penile function with tissue engineering techniques].

PubMed

Song, Lu-jie; Pan, Lian-jun; Xu, Yue-min

2007-04-01

Tissue engineering techniques, with their potential applied value for penile reconstruction, are of special interest for andrologists. The purpose of this review is to appraise the recent development and publications in this field. In the past few years, great efforts have been made to develop corpus cavernosum tissues by combining smooth muscle and endothelial cells seeded on biodegradable polyglycolic acid polymer (PGA) or acellular corporal collagen matrices scaffolds. Animal experiment demonstrated that the engineered corpus cavernosum achieved adequate structural and functional parameters. Engineered cartilage rods as an alternative for the current clinical standard of semirigid or inflatable penile implants could be created by seeding chondrocyte cylindrical PGA. A series of studies showed that, compared to commercially available silicone implants, the engineered rods were flexible, elastic and stable. Besides, a variety of decellularized biological materials have been used as grafts not only for substitution of tunica albuginea but also for penile enhancement, with promising results. For treating erectile dysfunction, a new approach to recovering erectile function by cell-based therapy could be the injection of functional cells into corpus cavernosum, which seemed to be promising when combined with cell manipulation by gene therapy prior to cell transfer.

Bioreactors as engineering support to treat cardiac muscle and vascular disease.

PubMed

Massai, Diana; Cerino, Giulia; Gallo, Diego; Pennella, Francesco; Deriu, Marco A; Rodriguez, Andres; Montevecchi, Franco M; Bignardi, Cristina; Audenino, Alberto; Morbiducci, Umberto

2013-01-01

Cardiovascular disease is the leading cause of morbidity and mortality in the Western World. The inability of fully differentiated, load-bearing cardiovascular tissues to in vivo regenerate and the limitations of the current treatment therapies greatly motivate the efforts of cardiovascular tissue engineering to become an effective clinical strategy for injured heart and vessels. For the effective production of organized and functional cardiovascular engineered constructs in vitro, a suitable dynamic environment is essential, and can be achieved and maintained within bioreactors. Bioreactors are technological devices that, while monitoring and controlling the culture environment and stimulating the construct, attempt to mimic the physiological milieu. In this study, a review of the current state of the art of bioreactor solutions for cardiovascular tissue engineering is presented, with emphasis on bioreactors and biophysical stimuli adopted for investigating the mechanisms influencing cardiovascular tissue development, and for eventually generating suitable cardiovascular tissue replacements.

Multifunctional cell-culture platform for aligned cell sheet monitoring, transfer printing, and therapy.

PubMed

Kim, Seok Joo; Cho, Hye Rim; Cho, Kyoung Won; Qiao, Shutao; Rhim, Jung Soo; Soh, Min; Kim, Taeho; Choi, Moon Kee; Choi, Changsoon; Park, Inhyuk; Hwang, Nathaniel S; Hyeon, Taeghwan; Choi, Seung Hong; Lu, Nanshu; Kim, Dae-Hyeong

2015-03-24

While several functional platforms for cell culturing have been proposed for cell sheet engineering, a soft integrated system enabling in vitro physiological monitoring of aligned cells prior to their in vivo applications in tissue regeneration has not been reported. Here, we present a multifunctional, soft cell-culture platform equipped with ultrathin stretchable nanomembrane sensors and graphene-nanoribbon cell aligners, whose system modulus is matched with target tissues. This multifunctional platform is capable of aligning plated cells and in situ monitoring of cellular physiological characteristics during proliferation and differentiation. In addition, it is successfully applied as an in vitro muscle-on-a-chip testing platform. Finally, a simple but high-yield transfer printing mechanism is proposed to deliver cell sheets for scaffold-free, localized cell therapy in vivo. The muscle-mimicking stiffness of the platform allows the high-yield transfer printing of multiple cell sheets and results in successful therapies in diseased animal models. Expansion of current results to stem cells will provide unique opportunities for emerging classes of tissue engineering and cell therapy technologies.

Nanotechnology meets 3D in vitro models: tissue engineered tumors and cancer therapies.

PubMed

da Rocha, E L; Porto, L M; Rambo, C R

2014-01-01

Advances in nanotechnology are providing to medicine a new dimension. Multifunctional nanomaterials with diagnostics and treatment modalities integrated in one nanoparticle or in cooperative nanosystems are promoting new insights to cancer treatment and diagnosis. The recent convergence between tissue engineering and cancer is gradually moving towards the development of 3D disease models that more closely resemble in vivo characteristics of tumors. However, the current nanomaterials based therapies are accomplished mainly in 2D cell cultures or in complex in vivo models. The development of new platforms to evaluate nano-based therapies in parallel with possible toxic effects will allow the design of nanomaterials for biomedical applications prior to in vivo studies. Therefore, this review focuses on how 3D in vitro models can be applied to study tumor biology, nanotoxicology and to evaluate nanomaterial based therapies. © 2013.

Artificial membrane-binding proteins stimulate oxygenation of stem cells during engineering of large cartilage tissue

NASA Astrophysics Data System (ADS)

Armstrong, James P. K.; Shakur, Rameen; Horne, Joseph P.; Dickinson, Sally C.; Armstrong, Craig T.; Lau, Katherine; Kadiwala, Juned; Lowe, Robert; Seddon, Annela; Mann, Stephen; Anderson, J. L. Ross; Perriman, Adam W.; Hollander, Anthony P.

2015-06-01

Restricted oxygen diffusion can result in central cell necrosis in engineered tissue, a problem that is exacerbated when engineering large tissue constructs for clinical application. Here we show that pre-treating human mesenchymal stem cells (hMSCs) with synthetic membrane-active myoglobin-polymer-surfactant complexes can provide a reservoir of oxygen capable of alleviating necrosis at the centre of hyaline cartilage. This is achieved through the development of a new cell functionalization methodology based on polymer-surfactant conjugation, which allows the delivery of functional proteins to the hMSC membrane. This new approach circumvents the need for cell surface engineering using protein chimerization or genetic transfection, and we demonstrate that the surface-modified hMSCs retain their ability to proliferate and to undergo multilineage differentiation. The functionalization technology is facile, versatile and non-disruptive, and in addition to tissue oxygenation, it should have far-reaching application in a host of tissue engineering and cell-based therapies.

Biomaterials and scaffolds in reparative medicine

NASA Technical Reports Server (NTRS)

Chaikof, Elliot L.; Matthew, Howard; Kohn, Joachim; Mikos, Antonios G.; Prestwich, Glenn D.; Yip, Christopher M.; McIntire, L. V. (Principal Investigator)

2002-01-01

Most approaches currently pursued or contemplated within the framework of reparative medicine, including cell-based therapies, artificial organs, and engineered living tissues, are dependent on our ability to synthesize or otherwise generate novel materials, fabricate or assemble materials into appropriate 2-D and 3-D forms, and precisely tailor material-related physical and biological properties so as to achieve a desired clinical response. This paper summarizes the scientific and technological opportunities within the fields of biomaterials science and molecular engineering that will likely establish new enabling technologies for cellular and molecular therapies directed at the repair, replacement, or reconstruction of diseased or damaged organs and tissues.

New Challenges for Intervertebral Disc Treatment Using Regenerative Medicine

PubMed Central

Masuda, Koichi

2010-01-01

The development of tissue engineering therapies for the intervertebral disc is challenging due to ambiguities of disease and pain mechanisms in patients, and lack of consensus on preclinical models for safety and efficacy testing. Although the issues associated with model selection for studying orthopedic diseases or treatments have been discussed often, the multifaceted challenges associated with developing intervertebral disc tissue engineering therapies require special discussion. This review covers topics relevant to the clinical translation of tissue-engineered technologies: (1) the unmet clinical need, (2) appropriate models for safety and efficacy testing, (3) the need for standardized model systems, and (4) the translational pathways leading to a clinical trial. For preclinical evaluation of new therapies, we recommend establishing biologic plausibility of efficacy and safety using models of increasing complexity, starting with cell culture, small animals (rats and rabbits), and then large animals (goat and minipig) that more closely mimic nutritional, biomechanical, and surgical realities of human application. The use of standardized and reproducible experimental procedures and outcome measures is critical for judging relative efficacy. Finally, success will hinge on carefully designed clinical trials with well-defined patient selection criteria, gold-standard controls, and objective outcome metrics to assess performance in the early postoperative period. PMID:19903086

Carbon Nanoparticle Enhance Photoacoustic Imaging and Therapy for Bone Tissue Engineering

NASA Astrophysics Data System (ADS)

Talukdar, Yahfi

Healing critical sized bone defects has been a challenge that led to innovations in tissue engineering scaffolds and biomechanical stimulations that enhance tissue regeneration. Carbon nanocomposite scaffolds have gained interest due to their enhanced mechanical properties. However, these scaffolds are only osteoconductive and not osteoinductive. Stimulating regeneration of bone tissue, osteoinductivity, has therefore been a subject of intense research. We propose the use of carbon nanoparticle enhanced photoacoustic (PA) stimulation to promote and enhance tissue regeneration in bone tissue-engineering scaffolds. In this study we test the feasibility of using carbon nanoparticles and PA for in vivo tissue engineering applications. To this end, we investigate 1) the effect of carbon nanoparticles, such as graphene oxide nanoplatelets (GONP), graphene oxide nano ribbons (GONR) and graphene nano onions (GNO), in vitro on mesenchymal stem cells (MSC), which are crucial for bone regeneration; 2) the use of PA imaging to detect and monitor tissue engineering scaffolds in vivo; and 3) we demonstrate the potential of carbon nanoparticle enhanced PA stimulation to promote tissue regeneration and healing in an in vivo rat fracture model. The results from these studies demonstrate that carbon nanoparticles such as GNOP, GONR and GNO do not affect viability or differentiation of MSCs and could potentially be used in vivo for tissue engineering applications. Furthermore, PA imaging can be used to detect and longitudinally monitor subcutaneously implanted carbon nanotubes incorporated polymeric nanocomposites in vivo. Oxygen saturation data from PA imaging could also be used as an indicator for tissue regeneration within the scaffolds. Lastly, we demonstrate that daily stimulation with carbon nanoparticle enhanced PA increases bone fracture healing. Rats stimulated for 10 minutes daily for two weeks showed 3 times higher new cortical bone BV/TV and 1.8 times bone mineral density, compared to non-stimulated controls. The results taken together indicate that carbon nanoparticle enhanced PA stimulation serves as an anabolic stimulus for bone regeneration. The results suggest opportunities towards the development of implant device combination therapies for bone loss due to disease or trauma.

Tissue Engineering the Cornea: The Evolution of RAFT

PubMed Central

Levis, Hannah J.; Kureshi, Alvena K.; Massie, Isobel; Morgan, Louise; Vernon, Amanda J.; Daniels, Julie T.

2015-01-01

Corneal blindness affects over 10 million people worldwide and current treatment strategies often involve replacement of the defective layer with healthy tissue. Due to a worldwide donor cornea shortage and the absence of suitable biological scaffolds, recent research has focused on the development of tissue engineering techniques to create alternative therapies. This review will detail how we have refined the simple engineering technique of plastic compression of collagen to a process we now call Real Architecture for 3D Tissues (RAFT). The RAFT production process has been standardised, and steps have been taken to consider Good Manufacturing Practice compliance. The evolution of this process has allowed us to create biomimetic epithelial and endothelial tissue equivalents suitable for transplantation and ideal for studying cell-cell interactions in vitro. PMID:25809689

Stem cells in drug discovery, tissue engineering, and regenerative medicine: emerging opportunities and challenges.

PubMed

Nirmalanandhan, Victor Sanjit; Sittampalam, G Sitta

2009-08-01

Stem cells, irrespective of their origin, have emerged as valuable reagents or tools in human health in the past 2 decades. Initially, a research tool to study fundamental aspects of developmental biology is now the central focus of generating transgenic animals, drug discovery, and regenerative medicine to address degenerative diseases of multiple organ systems. This is because stem cells are pluripotent or multipotent cells that can recapitulate developmental paths to repair damaged tissues. However, it is becoming clear that stem cell therapy alone may not be adequate to reverse tissue and organ damage in degenerative diseases. Existing small-molecule drugs and biologicals may be needed as "molecular adjuvants" or enhancers of stem cells administered in therapy or adult stem cells in the diseased tissues. Hence, a combination of stem cell-based, high-throughput screening and 3D tissue engineering approaches is necessary to advance the next wave of tools in preclinical drug discovery. In this review, the authors have attempted to provide a basic account of various stem cells types, as well as their biology and signaling, in the context of research in regenerative medicine. An attempt is made to link stem cells as reagents, pharmacology, and tissue engineering as converging fields of research for the next decade.

Fiber-reinforced scaffolds in soft tissue engineering

PubMed Central

Wang, Wei; Fan, Yubo; Wang, Xiumei; Watari, Fumio

2017-01-01

Abstract Soft tissue engineering has been developed as a new strategy for repairing damaged or diseased soft tissues and organs to overcome the limitations of current therapies. Since most of soft tissues in the human body are usually supported by collagen fibers to form a three-dimensional microstructure, fiber-reinforced scaffolds have the advantage to mimic the structure, mechanical and biological environment of natural soft tissues, which benefits for their regeneration and remodeling. This article reviews and discusses the latest research advances on design and manufacture of novel fiber-reinforced scaffolds for soft tissue repair and how fiber addition affects their structural characteristics, mechanical strength and biological activities in vitro and in vivo. In general, the concept of fiber-reinforced scaffolds with adjustable microstructures, mechanical properties and degradation rates can provide an effective platform and promising method for developing satisfactory biomechanically functional implantations for soft tissue engineering or regenerative medicine. PMID:28798872

Tissue-engineered cartilage with inducible and tunable immunomodulatory properties

PubMed Central

Glass, Katherine A.; Link, Jarrett M.; Brunger, Jonathan M.; Moutos, Franklin T.; Gersbach, Charles A.; Guilak, Farshid

2014-01-01

The pathogenesis of osteoarthritis is mediated in part by inflammatory cytokines including interleukin-1 (IL-1), which promote degradation of articular cartilage and prevent human mesenchymal stem cell (MSC) chondrogenesis. In this study, we combined gene therapy and functional tissue engineering to develop engineered cartilage with immunomodulatory properties that allow chondrogenesis in the presence of pathologic levels of IL-1 by inducing overexpression of IL-1 receptor antagonist (IL-1Ra) in MSCs via scaffold-mediated lentiviral gene delivery. A doxycycline-inducible vector was used to transduce MSCs in monolayer or within 3D woven PCL scaffolds to enable tunable IL-1Ra production. In the presence of IL-1, IL-1Ra-expressing engineered cartilage produced cartilage-specific extracellular matrix, while resisting IL-1-induced upregulation of matrix metalloproteinases and maintaining mechanical properties similar to native articular cartilage. The ability of functional engineered cartilage to deliver tunable anti-inflammatory cytokines to the joint may enhance the long-term success of therapies for cartilage injuries or osteoarthritis. PMID:24767790

Sustained secretion of anti-tumor necrosis factor α monoclonal antibody from ex vivo genetically engineered dermal tissue demonstrates therapeutic activity in mouse model of rheumatoid arthritis.

PubMed

Zafir-Lavie, Inbal; Miari, Reem; Sherbo, Shay; Krispel, Simi; Tal, Osnat; Liran, Atar; Shatil, Tamar; Badinter, Felix; Goltsman, Haim; Shapir, Nir; Benhar, Itai; Neil, Garry A; Panet, Amos

2017-08-01

Rheumatoid arthritis (RA) is a symmetric inflammatory polyarthritis associated with high concentrations of pro-inflammatory, cytokines including tumor necrosis factor (TNF)-α. Adalimumab is a monoclonal antibody (mAb) that binds TNF-α, and is widely used to treat RA. Despite its proven clinical efficacy, adalimumab and other therapeutic mAbs have disadvantages, including the requirement for repeated bolus injections and the appearance of treatment limiting anti-drug antibodies. To address these issues, we have developed an innovative ex vivo gene therapy approach, termed transduced autologous restorative gene therapy (TARGT), to produce and secrete adalimumab for the treatment of RA. Helper-dependent (HD) adenovirus vector containing adalimumab light and heavy chain coding sequences was used to transduce microdermal tissues and cells of human and mouse origin ex vivo, rendering sustained secretion of active adalimumab. The genetically engineered tissues were subsequently implanted in a mouse model of RA. Transduced human microdermal tissues implanted in SCID mice demonstrated 49 days of secretion of active adalimumab in the blood, at levels of tens of microgram per milliliter. In addition, transduced autologous dermal cells were implanted in the RA mouse model and demonstrated statistically significant amelioration in RA symptoms compared to naïve cell implantation and were similar to recombinant adalimumab bolus injections. The results of the present study report microdermal tissues engineered to secrete active adalimumab as a proof of concept for sustained secretion of antibody from the novel ex vivo gene therapy TARGT platform. This technology may now be applied to a range of antibodies for the therapy of other diseases. Copyright © 2017 John Wiley & Sons, Ltd.

Real-time quantitation of internal metabolic activity of three-dimensional engineered tissues using an oxygen microelectrode and optical coherence tomography.

PubMed

Kagawa, Yuki; Haraguchi, Yuji; Tsuneda, Satoshi; Shimizu, Tatsuya

2017-05-01

Recent progress in tissue engineering technology has enabled us to develop thick tissue constructs that can then be transplanted in regenerative therapies. In clinical situations, it is vital that the engineered tissues to be implanted are safe and functional before use. However, there is currently a limited number of studies on real-time quality evaluation of thick living tissue constructs. Here we developed a system for quantifying the internal activities of engineered tissues, from which we can evaluate its quality in real-time. The evaluation was achieved by measuring oxygen concentration profiles made along the vertical axis and the thickness of the tissues estimated from cross-sectional images obtained noninvasively by an optical coherence tomography system. Using our novel system, we obtained (i) oxygen concentration just above the tissues, (ii) gradient of oxygen along vertical axis formed above the tissues within culture medium, and (iii) gradient of oxygen formed within the tissues in real-time. Investigating whether these three parameters could be used to evaluate engineered tissues during culturing, we found that only the third parameter was a good candidate. This implies that the activity of living engineered tissues can be monitored in real-time by measuring the oxygen gradient within the tissues. The proposed measuring strategy can be applied to developing more efficient culturing methods to support the fabrication of engineered thick tissues, as well as providing methods to confirm the quality in real-time. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 855-864, 2017. © 2015 Wiley Periodicals, Inc.

Cardiovascular Bio-Engineering: Current State of the Art.

PubMed

Simon-Yarza, Teresa; Bataille, Isabelle; Letourneur, Didier

2017-04-01

Despite the introduction of new drugs and innovative devices contributing in the last years to improve patients' quality of life, morbidity and mortality from cardiovascular diseases remain high. There is an urgent need for addressing the underlying problem of the loss of cardiac or vascular tissues and therefore developing new therapies. Autologous vascular transplants are often limited by poor quality of donor sites and heart organ transplantation by donor shortage. Vascular and cardiac tissue engineering, whose aim is to repair or replace cardiovascular tissues by the use of cells, engineering and materials, as well as biochemical and physicochemical factors, appears in this scenario as a promising tool to repair the damaged hearts and vessels. We will present a general overview on the fundamentals in the area of cardiac and vascular tissue engineering as well as on the latest progresses and challenges.

Tissue Engineering of Urinary Bladder and Urethra: Advances from Bench to Patients

PubMed Central

Bouhout, Sara; Chabaud, Stéphane; Bolduc, Stéphane

2013-01-01

Urinary tract is subjected to many varieties of pathologies since birth including congenital anomalies, trauma, inflammatory lesions, and malignancy. These diseases necessitate the replacement of involved organs and tissues. Shortage of organ donation, problems of immunosuppression, and complications associated with the use of nonnative tissues have urged clinicians and scientists to investigate new therapies, namely, tissue engineering. Tissue engineering follows principles of cell transplantation, materials science, and engineering. Epithelial and muscle cells can be harvested and used for reconstruction of the engineered grafts. These cells must be delivered in a well-organized and differentiated condition because water-seal epithelium and well-oriented muscle layer are needed for proper function of the substitute tissues. Synthetic or natural scaffolds have been used for engineering lower urinary tract. Harnessing autologous cells to produce their own matrix and form scaffolds is a new strategy for engineering bladder and urethra. This self-assembly technique avoids the biosafety and immunological reactions related to the use of biodegradable scaffolds. Autologous equivalents have already been produced for pigs (bladder) and human (urethra and bladder). The purpose of this paper is to present a review for the existing methods of engineering bladder and urethra and to point toward perspectives for their replacement. PMID:24453796

Advanced therapies of skin injuries.

PubMed

Maver, Tina; Maver, Uroš; Kleinschek, Karin Stana; Raščan, Irena Mlinarič; Smrke, Dragica Maja

2015-12-01

The loss of tissue is still one of the most challenging problems in healthcare. Efficient laboratory expansion of skin tissue to reproduce the skins barrier function can make the difference between life and death for patients with extensive full-thickness burns, chronic wounds, or genetic disorders such as bullous conditions. This engineering has been initiated based on the acute need in the 1980s and today, tissue-engineered skin is the reality. The human skin equivalents are available not only as models for permeation and toxicity screening, but are frequently applied in vivo as clinical skin substitutes. This review aims to introduce the most important recent development in the extensive field of tissue engineering and to describe already approved, commercially available skin substitutes in clinical use.

Characterization and evaluation of graphene oxide scaffold for periodontal wound healing of class II furcation defects in dog.

PubMed

Kawamoto, Kohei; Miyaji, Hirofumi; Nishida, Erika; Miyata, Saori; Kato, Akihito; Tateyama, Akito; Furihata, Tomokazu; Shitomi, Kanako; Iwanaga, Toshihiko; Sugaya, Tsutomu

2018-01-01

The 3-dimensional scaffold plays a key role in volume and quality of repair tissue in periodontal tissue engineering therapy. We fabricated a novel 3D collagen scaffold containing carbon-based 2-dimensional layered material, named graphene oxide (GO). The aim of this study was to characterize and assess GO scaffold for periodontal tissue healing of class II furcation defects in dog. GO scaffolds were prepared by coating the surface of a 3D collagen sponge scaffold with GO dispersion. Scaffolds were characterized using cytotoxicity and tissue reactivity tests. In addition, GO scaffold was implanted into dog class II furcation defects and periodontal healing was investigated at 4 weeks postsurgery. GO scaffold exhibited low cytotoxicity and enhanced cellular ingrowth behavior and rat bone forming ability. In addition, GO scaffold stimulated healing of dog class II furcation defects. Periodontal attachment formation, including alveolar bone, periodontal ligament-like tissue, and cementum-like tissue, was significantly increased by GO scaffold implantation, compared with untreated scaffold. The results suggest that GO scaffold is biocompatible and possesses excellent bone and periodontal tissue formation ability. Therefore, GO scaffold would be beneficial for periodontal tissue engineering therapy.

An update to space biomedical research: tissue engineering in microgravity bioreactors.

PubMed

Barzegari, Abolfazl; Saei, Amir Ata

2012-01-01

The severe need for constructing replacement tissues in organ transplanta-tion has necessitated the development of tissue engineering approaches and bioreactors that can bring these approaches to reality. The inherent limitations of conventional bioreactors in generating realistic tissue constructs led to the devise of the microgravity tissue engineering that uses Rotating Wall Vessel (RWV) bioreactors initially developed by NASA. In this review article, we intend to highlight some major advances and accomplishments in the rapidly-growing field of tissue engineering that could not be achieved without using microgravity. Research is now focused on assembly of 3 dimensional (3D) tissue fragments from various cell types in human body such as chon-drocytes, osteoblasts, embryonic and mesenchymal stem cells, hepatocytes and pancreas islet cells. Hepatocytes cultured under microgravity are now being used in extracorporeal bioartificial liver devices. Tissue constructs can be used not only in organ replacement therapy, but also in pharmaco-toxicology and food safety assessment. 3D models of vari-ous cancers may be used in studying cancer development and biology or in high-throughput screening of anticancer drug candidates. Finally, 3D heterogeneous assemblies from cancer/immune cells provide models for immunotherapy of cancer. Tissue engineering in (simulated) microgravity has been one of the stunning impacts of space research on biomedical sciences and their applications on earth.

Tissue-engineered human bioartificial muscles expressing a foreign recombinant protein for gene therapy

NASA Technical Reports Server (NTRS)

Powell, C.; Shansky, J.; Del Tatto, M.; Forman, D. E.; Hennessey, J.; Sullivan, K.; Zielinski, B. A.; Vandenburgh, H. H.

1999-01-01

Murine skeletal muscle cells transduced with foreign genes and tissue engineered in vitro into bioartificial muscles (BAMs) are capable of long-term delivery of soluble growth factors when implanted into syngeneic mice (Vandenburgh et al., 1996b). With the goal of developing a therapeutic cell-based protein delivery system for humans, similar genetic tissue-engineering techniques were designed for human skeletal muscle stem cells. Stem cell myoblasts were isolated, cloned, and expanded in vitro from biopsied healthy adult (mean age, 42 +/- 2 years), and elderly congestive heart failure patient (mean age, 76 +/- 1 years) skeletal muscle. Total cell yield varied widely between biopsies (50 to 672 per 100 mg of tissue, N = 10), but was not significantly different between the two patient groups. Percent myoblasts per biopsy (73 +/- 6%), number of myoblast doublings prior to senescence in vitro (37 +/- 2), and myoblast doubling time (27 +/- 1 hr) were also not significantly different between the two patient groups. Fusion kinetics of the myoblasts were similar for the two groups after 20-22 doublings (74 +/- 2% myoblast fusion) when the biopsy samples had been expanded to 1 to 2 billion muscle cells, a number acceptable for human gene therapy use. The myoblasts from the two groups could be equally transduced ex vivo with replication-deficient retroviral expression vectors to secrete 0.5 to 2 microg of a foreign protein (recombinant human growth hormone, rhGH)/10(6) cells/day, and tissue engineered into human BAMs containing parallel arrays of differentiated, postmitotic myofibers. This work suggests that autologous human skeletal myoblasts from a potential patient population can be isolated, genetically modified to secrete foreign proteins, and tissue engineered into implantable living protein secretory devices for therapeutic use.

Micropatterned nanostructures: a bioengineered approach to mass-produce functional myocardial grafts.

PubMed

Serpooshan, Vahid; Mahmoudi, Morteza

2015-02-13

Cell-based therapies are a recently established path for treating a wide range of human disease. Tissue engineering of contractile heart muscle for replacement therapy is among the most exciting and important of these efforts. However, current in vitro techniques of cultivating functional mature cardiac grafts have only been moderately successful due to the poor capability of traditional two-dimensional cell culture systems to recapitulate necessary in vivo conditions. In this issue, Kiefer et al introduce a laser-patterned nanostructured substrate (Al/Al2O3 nanowires) for efficient maintenance of oriented human cardiomyocytes, with great potential to open new roads to mass-production of contractile myocardial grafts for cardiovascular tissue engineering.

Micropatterned nanostructures: a bioengineered approach to mass-produce functional myocardial grafts

NASA Astrophysics Data System (ADS)

Serpooshan, Vahid; Mahmoudi, Morteza

2015-02-01

Cell-based therapies are a recently established path for treating a wide range of human disease. Tissue engineering of contractile heart muscle for replacement therapy is among the most exciting and important of these efforts. However, current in vitro techniques of cultivating functional mature cardiac grafts have only been moderately successful due to the poor capability of traditional two-dimensional cell culture systems to recapitulate necessary in vivo conditions. In this issue, Kiefer et al [1] introduce a laser-patterned nanostructured substrate (Al/Al2O3 nanowires) for efficient maintenance of oriented human cardiomyocytes, with great potential to open new roads to mass-production of contractile myocardial grafts for cardiovascular tissue engineering.

Advances in combining gene therapy with cell and tissue engineering-based approaches to enhance healing of the meniscus

PubMed Central

Cucchiarini, M.; McNulty, A.L.; Mauck, R.L.; Setton, L.A.; Guilak, F.; Madry, H.

2017-01-01

SUMMARY Meniscal lesions are common problems in orthopaedic surgery and sports medicine, and injury or loss of the meniscus accelerates the onset of knee osteoarthritis. Despite a variety of therapeutic options in the clinics, there is a critical need for improved treatments to enhance meniscal repair. In this regard, combining gene-, cell-, and tissue engineering-based approaches is an attractive strategy to generate novel, effective therapies to treat meniscal lesions. In the present work, we provide an overview of the tools currently available to improve meniscal repair and discuss the progress and remaining challenges for potential future translation in patients. PMID:27063441

A Review of Injectable Polymeric Hydrogel Systems for Application in Bone Tissue Engineering.

PubMed

Kondiah, Pariksha J; Choonara, Yahya E; Kondiah, Pierre P D; Marimuthu, Thashree; Kumar, Pradeep; du Toit, Lisa C; Pillay, Viness

2016-11-21

Biodegradable, stimuli-responsive polymers are essential platforms in the field of drug delivery and injectable biomaterials for application of bone tissue engineering. Various thermo-responsive hydrogels display water-based homogenous properties to encapsulate, manipulate and transfer its contents to the surrounding tissue, in the least invasive manner. The success of bioengineered injectable tissue modified delivery systems depends significantly on their chemical, physical and biological properties. Irrespective of shape and defect geometry, injectable therapy has an unparalleled advantage in which intricate therapy sites can be effortlessly targeted with minimally invasive procedures. Using material testing, it was found that properties of stimuli-responsive hydrogel systems enhance cellular responses and cell distribution at any site prior to the transitional phase leading to gelation. The substantially hydrated nature allows significant simulation of the extracellular matrix (ECM), due to its similar structural properties. Significant current research strategies have been identified and reported to date by various institutions, with particular attention to thermo-responsive hydrogel delivery systems, and their pertinent focus for bone tissue engineering. Research on future perspective studies which have been proposed for evaluation, have also been reported in this review, directing considerable attention to the modification of delivering natural and synthetic polymers, to improve their biocompatibility and mechanical properties.

An adipoinductive role of inflammation in adipose tissue engineering: key factors in the early development of engineered soft tissues.

PubMed

Lilja, Heidi E; Morrison, Wayne A; Han, Xiao-Lian; Palmer, Jason; Taylor, Caroline; Tee, Richard; Möller, Andreas; Thompson, Erik W; Abberton, Keren M

2013-05-15

Tissue engineering and cell implantation therapies are gaining popularity because of their potential to repair and regenerate tissues and organs. To investigate the role of inflammatory cytokines in new tissue development in engineered tissues, we have characterized the nature and timing of cell populations forming new adipose tissue in a mouse tissue engineering chamber (TEC) and characterized the gene and protein expression of cytokines in the newly developing tissues. EGFP-labeled bone marrow transplant mice and MacGreen mice were implanted with TEC for periods ranging from 0.5 days to 6 weeks. Tissues were collected at various time points and assessed for cytokine expression through ELISA and mRNA analysis or labeled for specific cell populations in the TEC. Macrophage-derived factors, such as monocyte chemotactic protein-1 (MCP-1), appear to induce adipogenesis by recruiting macrophages and bone marrow-derived precursor cells to the TEC at early time points, with a second wave of nonbone marrow-derived progenitors. Gene expression analysis suggests that TNFα, LCN-2, and Interleukin 1β are important in early stages of neo-adipogenesis. Increasing platelet-derived growth factor and vascular endothelial cell growth factor expression at early time points correlates with preadipocyte proliferation and induction of angiogenesis. This study provides new information about key elements that are involved in early development of new adipose tissue.

Genetically Engineered Vaccinia Viruses As Agents for Cancer Treatment, Imaging, and Transgene Delivery

PubMed Central

Haddad, Dana

2017-01-01

Despite advances in technology, the formidable challenge of treating cancer, especially if advanced, still remains with no significant improvement in survival rates, even with the most common forms of cancer. Oncolytic viral therapies have shown great promise for the treatment of various cancers, with the possible advantages of stronger treatment efficacy compared to conventional therapy due to higher tumor selectivity, and less toxicity. They are able to preferentially and selectively propagate in cancer cells, consequently destroying tumor tissue mainly via cell lysis, while leaving non-cancerous tissues unharmed. Several wild-type and genetically engineered vaccinia virus (VACV) strains have been tested in both preclinical and clinical trials with promising results. Greater understanding and advancements in molecular biology have enabled the generation of genetically engineered oncolytic viruses for safer and more efficacious treatment, including arming VACVs with cytokines and immunostimulatory molecules, anti-angiogenic agents, and enzyme prodrug therapy, in addition to combining VACVs with conventional external and systemic radiotherapy, chemotherapy, immunotherapy, and other virus strains. Furthermore, novel oncolytic vaccinia virus strains have been generated that express reporter genes for the tracking and imaging of viral therapy and monitoring of therapeutic response. Further study is needed to unlock VACVs’ full potential as part of the future of cancer therapy. PMID:28589082

Salidroside promotes peripheral nerve regeneration based on tissue engineering strategy using Schwann cells and PLGA: in vitro and in vivo

NASA Astrophysics Data System (ADS)

Liu, Hui; Lv, Peizhen; Zhu, Yongjia; Wu, Huayu; Zhang, Kun; Xu, Fuben; Zheng, Li; Zhao, Jinmin

2017-01-01

Salidriside (SDS), a phenylpropanoid glycoside derived from Rhodiola rosea L, has been shown to be neuroprotective in many studies, which may be promising in nerve recovery. In this study, the neuroprotective effects of SDS on engineered nerve constructed by Schwann cells (SCs) and Poly (lactic-co-glycolic acid) (PLGA) were studied in vitro. We further investigated the effect of combinational therapy of SDS and PLGA/SCs based tissue engineering on peripheral nerve regeneration based on the rat model of nerve injury by sciatic transection. The results showed that SDS dramatically enhanced the proliferation and function of SCs. The underlying mechanism may be that SDS affects SCs growth through the modulation of neurotrophic factors (BDNF, GDNF and CNTF). 12 weeks after implantation with a 12 mm gap of sciatic nerve injury, SDS-PLGA/SCs achieved satisfying outcomes of nerve regeneration, as evidenced by morphological and functional improvements upon therapy by SDS, PLGA/SCs or direct suture group assessed by sciatic function index, nerve conduction assay, HE staining and immunohistochemical analysis. Our results demonstrated the significant role of introducing SDS into neural tissue engineering to promote nerve regeneration.

Clinical application of cell, gene and tissue therapies in Spain.

PubMed

Gálvez-Martín, P; Ruiz, A; Clares, B

2018-05-01

Scientific and technical advances in the areas of biomedicine and regenerative medicine have enabled the development of new treatments known as "advanced therapies", which encompass cell therapy, genetics and tissue engineering. The biologic products that can be manufactured from these elements are classified from the standpoint of the Spanish Agency of Medication and Health Products in advanced drug therapies, blood products and transplants. This review seeks to provide scientific and administrative information for clinicians on the use of these biologic resources. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

Three-Dimensional Printing and Cell Therapy for Wound Repair.

PubMed

van Kogelenberg, Sylvia; Yue, Zhilian; Dinoro, Jeremy N; Baker, Christopher S; Wallace, Gordon G

2018-05-01

Significance: Skin tissue damage is a major challenge and a burden on healthcare systems, from burns and other trauma to diabetes and vascular disease. Although the biological complexities are relatively well understood, appropriate repair mechanisms are scarce. Three-dimensional bioprinting is a layer-based approach to regenerative medicine, whereby cells and cell-based materials can be dispensed in fine spatial arrangements to mimic native tissue. Recent Advances: Various bioprinting techniques have been employed in wound repair-based skin tissue engineering, from laser-induced forward transfer to extrusion-based methods, and with the investigation of the benefits and shortcomings of each, with emphasis on biological compatibility and cell proliferation, migration, and vitality. Critical issues: Development of appropriate biological inks and the vascularization of newly developed tissues remain a challenge within the field of skin tissue engineering. Future Directions: Progress within bioprinting requires close interactions between material scientists, tissue engineers, and clinicians. Microvascularization, integration of multiple cell types, and skin appendages will be essential for creation of complex skin tissue constructs.

Tissue-engineered cartilage with inducible and tunable immunomodulatory properties.

PubMed

Glass, Katherine A; Link, Jarrett M; Brunger, Jonathan M; Moutos, Franklin T; Gersbach, Charles A; Guilak, Farshid

2014-07-01

The pathogenesis of osteoarthritis is mediated in part by inflammatory cytokines including interleukin-1 (IL-1), which promote degradation of articular cartilage and prevent human mesenchymal stem cell (MSC) chondrogenesis. In this study, we combined gene therapy and functional tissue engineering to develop engineered cartilage with immunomodulatory properties that allow chondrogenesis in the presence of pathologic levels of IL-1 by inducing overexpression of IL-1 receptor antagonist (IL-1Ra) in MSCs via scaffold-mediated lentiviral gene delivery. A doxycycline-inducible vector was used to transduce MSCs in monolayer or within 3D woven PCL scaffolds to enable tunable IL-1Ra production. In the presence of IL-1, IL-1Ra-expressing engineered cartilage produced cartilage-specific extracellular matrix, while resisting IL-1-induced upregulation of matrix metalloproteinases and maintaining mechanical properties similar to native articular cartilage. The ability of functional engineered cartilage to deliver tunable anti-inflammatory cytokines to the joint may enhance the long-term success of therapies for cartilage injuries or osteoarthritis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biomaterials in myocardial tissue engineering

PubMed Central

Reis, Lewis A.; Chiu, Loraine L. Y.; Feric, Nicole; Fu, Lara; Radisic, Milica

2016-01-01

Cardiovascular disease is the leading cause of death in the developed world, and as such there is a pressing need for treatment options. Cardiac tissue engineering emerged from the need to develop alternate sources and methods of replacing tissue damaged by cardiovascular diseases, as the ultimate treatment option for many who suffer from end-stage heart failure is a heart transplant. In this review we focus on biomaterial approaches to augment injured or impaired myocardium with specific emphasis on: the design criteria for these biomaterials; the types of scaffolds—composed of natural or synthetic biomaterials, or decellularized extracellular matrix—that have been used to develop cardiac patches and tissue models; methods to vascularize scaffolds and engineered tissue, and finally injectable biomaterials (hydrogels)designed for endogenous repair, exogenous repair or as bulking agents to maintain ventricular geometry post-infarct. The challenges facing the field and obstacles that must be overcome to develop truly clinically viable cardiac therapies are also discussed. PMID:25066525

Overcoming the Roadblocks to Cardiac Cell Therapy Using Tissue Engineering.

PubMed

Yanamandala, Mounica; Zhu, Wuqiang; Garry, Daniel J; Kamp, Timothy J; Hare, Joshua M; Jun, Ho-Wook; Yoon, Young-Sup; Bursac, Nenad; Prabhu, Sumanth D; Dorn, Gerald W; Bolli, Roberto; Kitsis, Richard N; Zhang, Jianyi

2017-08-08

Transplantations of various stem cells or their progeny have repeatedly improved cardiac performance in animal models of myocardial injury; however, the benefits observed in clinical trials have been generally less consistent. Some of the recognized challenges are poor engraftment of implanted cells and, in the case of human cardiomyocytes, functional immaturity and lack of electrical integration, leading to limited contribution to the heart's contractile activity and increased arrhythmogenic risks. Advances in tissue and genetic engineering techniques are expected to improve the survival and integration of transplanted cells, and to support structural, functional, and bioenergetic recovery of the recipient hearts. Specifically, application of a prefabricated cardiac tissue patch to prevent dilation and to improve pumping efficiency of the infarcted heart offers a promising strategy for making stem cell therapy a clinical reality. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Bioprocess Forces and Their Impact on Cell Behavior: Implications for Bone Regeneration Therapy

PubMed Central

Brindley, David; Moorthy, Kishaani; Lee, Jae-Ho; Mason, Chris; Kim, Hae-Won; Wall, Ivan

2011-01-01

Bioprocess forces such as shear stress experienced during routine cell culture are considered to be harmful to cells. However, the impact of physical forces on cell behavior is an area of growing interest within the tissue engineering community, and it is widely acknowledged that mechanical stimulation including shear stress can enhance osteogenic differentiation. This paper considers the effects of bioprocess shear stress on cell responses such as survival and proliferation in several contexts, including suspension-adapted cells used for recombinant protein and monoclonal antibody manufacture, adherent cells for therapy in suspension, and adherent cells attached to their growth substrates. The enhanced osteogenic differentiation that fluid flow shear stress is widely found to induce is discussed, along with the tissue engineering of mineralized tissue using perfusion bioreactors. Recent evidence that bioprocess forces produced during capillary transfer or pipetting of cell suspensions can enhance osteogenic responses is also discussed. PMID:21904661

Murine tissue-engineered stomach demonstrates epithelial differentiation.

PubMed

Speer, Allison L; Sala, Frederic G; Matthews, Jamil A; Grikscheit, Tracy C

2011-11-01

Gastric cancer remains the second largest cause of cancer-related mortality worldwide. Postgastrectomy morbidity is considerable and quality of life is poor. Tissue-engineered stomach is a potential replacement solution to restore adequate food reservoir and gastric physiology. In this study, we performed a detailed investigation of the development of tissue-engineered stomach in a mouse model, specifically evaluating epithelial differentiation, proliferation, and the presence of putative stem cell markers. Organoid units were isolated from <3 wk-old mouse glandular stomach and seeded onto biodegradable scaffolds. The constructs were implanted into the omentum of adult mice. Implants were harvested at designated time points and analyzed with histology and immunohistochemistry. Tissue-engineered stomach grows as an expanding sphere with a simple columnar epithelium organized into gastric glands and an adjacent muscularis. The regenerated gastric epithelium demonstrates differentiation of all four cell types: mucous, enteroendocrine, chief, and parietal cells. Tissue-engineered stomach epithelium proliferates at a rate comparable to native glandular stomach and expresses two putative stem cell markers: DCAMKL-1 and Lgr5. This study demonstrates the successful generation of tissue-engineered stomach in a mouse model for the first time. Regenerated gastric epithelium is able to appropriately proliferate and differentiate. The generation of murine tissue-engineered stomach is a necessary advance as it provides the transgenic tools required to investigate the molecular and cellular mechanisms of this regenerative process. Delineating the mechanism of how tissue-engineered stomach develops in vivo is an important precursor to its use as a human stomach replacement therapy. Copyright © 2011 Elsevier Inc. All rights reserved.

Liver regenerative medicine: advances and challenges.

PubMed

Chistiakov, Dimitry A

2012-01-01

Liver transplantation is the standard care for many end-stage liver diseases. However, donor organs are scarce and some people succumb to liver failure before a donor is found. Liver regenerative medicine is a special interdisciplinary field of medicine focused on the development of new therapies incorporating stem cells, gene therapy and engineered tissues in order to repair or replace the damaged organ. In this review we consider the emerging progress achieved in the hepatic regenerative medicine within the last decade. The review starts with the characterization of liver organogenesis, fetal and adult stem/progenitor cells. Then, applications of primary hepatocytes, embryonic and adult (mesenchymal, hematopoietic and induced pluripotent) stem cells in cell therapy of liver diseases are considered. Current advances and challenges in producing mature hepatocytes from stem/progenitor cells are discussed. A section about hepatic tissue engineering includes consideration of synthetic and natural biomaterials in engineering scaffolds, strategies and achievements in the development of 3D bioactive matrices and 3D hepatocyte cultures, liver microengineering, generating bioartificial liver and prospects for fabrication of the bioengineered liver. Copyright © 2012 S. Karger AG, Basel.

Cell therapy, 3D culture systems and tissue engineering for cardiac regeneration.

PubMed

Emmert, Maximilian Y; Hitchcock, Robert W; Hoerstrup, Simon P

2014-04-01

Ischemic Heart Disease (IHD) still represents the "Number One Killer" worldwide accounting for the death of numerous patients. However the capacity for self-regeneration of the adult heart is very limited and the loss of cardiomyocytes in the infarcted heart leads to continuous adverse cardiac-remodeling which often leads to heart-failure (HF). The concept of regenerative medicine comprising cell-based therapies, bio-engineering technologies and hybrid solutions has been proposed as a promising next-generation approach to address IHD and HF. Numerous strategies are under investigation evaluating the potential of regenerative medicine on the failing myocardium including classical cell-therapy concepts, three-dimensional culture techniques and tissue-engineering approaches. While most of these regenerative strategies have shown great potential in experimental studies, the translation into a clinical setting has either been limited or too rapid leaving many key questions unanswered. This review summarizes the current state-of-the-art, important challenges and future research directions as to regenerative approaches addressing IHD and resulting HF. Copyright © 2014 Elsevier B.V. All rights reserved.

Advanced therapies for the treatment of hemophilia: future perspectives.

PubMed

Liras, Antonio; Segovia, Cristina; Gabán, Aline S

2012-12-13

Monogenic diseases are ideal candidates for treatment by the emerging advanced therapies, which are capable of correcting alterations in protein expression that result from genetic mutation. In hemophilia A and B such alterations affect the activity of coagulation factors VIII and IX, respectively, and are responsible for the development of the disease. Advanced therapies may involve the replacement of a deficient gene by a healthy gene so that it generates a certain functional, structural or transport protein (gene therapy); the incorporation of a full array of healthy genes and proteins through perfusion or transplantation of healthy cells (cell therapy); or tissue transplantation and formation of healthy organs (tissue engineering). For their part, induced pluripotent stem cells have recently been shown to also play a significant role in the fields of cell therapy and tissue engineering. Hemophilia is optimally suited for advanced therapies owing to the fact that, as a monogenic condition, it does not require very high expression levels of a coagulation factor to reach moderate disease status. As a result, significant progress has been possible with respect to these kinds of strategies, especially in the fields of gene therapy (by using viral and non-viral vectors) and cell therapy (by means of several types of target cells). Thus, although still considered a rare disorder, hemophilia is now recognized as a condition amenable to gene therapy, which can be administered in the form of lentiviral and adeno-associated vectors applied to adult stem cells, autologous fibroblasts, platelets and hematopoietic stem cells; by means of non-viral vectors; or through the repair of mutations by chimeric oligonucleotides. In hemophilia, cell therapy approaches have been based mainly on transplantation of healthy cells (adult stem cells or induced pluripotent cell-derived progenitor cells) in order to restore alterations in coagulation factor expression.

78 FR 78370 - Government-Owned Inventions; Availability for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-26

... via the antibody binding fragment of the CAR. By engineering a T-cell to express a CAR that is...) developed in tissue that has been propagated by serial transplantation (rather than cell culture), (b... marrow transplantation, stem cell therapy, tissue regeneration) Competitive Advantages: Labeling markers...

Micro- and Nanoscale Hydrogel Systems for Drug Delivery and Tissue Engineering

PubMed Central

Schwall, Christine T.; Banerjee, Ipsita A.

2009-01-01

The pursuit for targeted drug delivery systems has led to the development of highly improved biomaterials with enhanced biocompatibility and biodegradability properties. Micro- and nanoscale components of hydrogels prepared from both natural and artificial components have been gaining significant importance due to their potential uses in cell based therapies, tissue engineering, liquid micro-lenses, cancer therapy, and drug delivery. In this review some of the recent methodologies used in the preparation of a number of synthetic hydrogels such as poly(N-isopropylacrylamide) (pNIPAm), poly(ethylene glycol) (PEG), poly(ethylene oxide) (PEO), polyvinyl alcohol methylacrylate co-polymers (PVA-MA) and polylactic acid (PLA), as well as some of the natural hydrogels and their applications have been discussed in detail.

Advances in combining gene therapy with cell and tissue engineering-based approaches to enhance healing of the meniscus.

PubMed

Cucchiarini, M; McNulty, A L; Mauck, R L; Setton, L A; Guilak, F; Madry, H

2016-08-01

Meniscal lesions are common problems in orthopaedic surgery and sports medicine, and injury or loss of the meniscus accelerates the onset of knee osteoarthritis (OA). Despite a variety of therapeutic options in the clinics, there is a critical need for improved treatments to enhance meniscal repair. In this regard, combining gene-, cell-, and tissue engineering-based approaches is an attractive strategy to generate novel, effective therapies to treat meniscal lesions. In the present work, we provide an overview of the tools currently available to improve meniscal repair and discuss the progress and remaining challenges for potential future translation in patients. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

[Strategies to choose scaffold materials for tissue engineering].

PubMed

Gao, Qingdong; Zhu, Xulong; Xiang, Junxi; Lü, Yi; Li, Jianhui

2016-02-01

Current therapies of organ failure or a wide range of tissue defect are often not ideal. Transplantation is the only effective way for long time survival. But it is hard to meet huge patients demands because of donor shortage, immune rejection and other problems. Tissue engineering could be a potential option. Choosing a suitable scaffold material is an essential part of it. According to different sources, tissue engineering scaffold materials could be divided into three types which are natural and its modified materials, artificial and composite ones. The purpose of tissue engineering scaffold is to repair the tissues or organs damage, so could reach the ideal recovery in its function and structure aspect. Therefore, tissue engineering scaffold should even be as close as much to the original tissue or organs in function and structure. We call it "organic scaffold" and this strategy might be the drastic perfect substitute for the tissues or organs in concern. Optimized organization with each kind scaffold materials could make up for biomimetic structure and function of the tissue or organs. Scaffold material surface modification, optimized preparation procedure and cytosine sustained-release microsphere addition should be considered together. This strategy is expected to open new perspectives for tissue engineering. Multidisciplinary approach including material science, molecular biology, and engineering might find the most ideal tissue engineering scaffold. Using the strategy of drawing on each other strength and optimized organization with each kind scaffold material to prepare a multifunctional biomimetic tissue engineering scaffold might be a good method for choosing tissue engineering scaffold materials. Our research group had differentiated bone marrow mesenchymal stem cells into bile canaliculi like cells. We prepared poly(L-lactic acid)/poly(ε-caprolactone) biliary stent. The scaffold's internal played a part in the long-term release of cytokines which mixed with sustained-release nano-microsphere containing growth factors. What's more, the stent internal surface coated with glue/collagen matrix mixing layer containing bFGF and EGF so could supplying the early release of the two cytokines. Finally, combining the poly(L-lactic acid)/poly(ε-caprolactone) biliary stent with the induced cells was the last step for preparing tissue-engineered bile duct. This literature reviewed a variety of the existing tissue engineering scaffold materials and briefly introduced the impact factors on the characteristics of tissue engineering scaffold materials such as preparation procedure, surface modification of scaffold, and so on. We explored the choosing strategy of desired tissue engineering scaffold materials.

Next Generation Mesenchymal Stem Cell (MSC)–Based Cartilage Repair Using Scaffold-Free Tissue Engineered Constructs Generated with Synovial Mesenchymal Stem Cells

PubMed Central

Shimomura, Kazunori; Ando, Wataru; Moriguchi, Yu; Sugita, Norihiko; Yasui, Yukihiko; Koizumi, Kota; Fujie, Hiromichi; Hart, David A.; Yoshikawa, Hideki

2015-01-01

Because of its limited healing capacity, treatments for articular cartilage injuries are still challenging. Since the first report by Brittberg, autologous chondrocyte implantation has been extensively studied. Recently, as an alternative for chondrocyte-based therapy, mesenchymal stem cell–based therapy has received considerable research attention because of the relative ease in handling for tissue harvest, and subsequent cell expansion and differentiation. This review summarizes latest development of stem cell therapies in cartilage repair with special attention to scaffold-free approaches. PMID:27340513

Characterization and evaluation of graphene oxide scaffold for periodontal wound healing of class II furcation defects in dog

PubMed Central

Kawamoto, Kohei; Miyaji, Hirofumi; Nishida, Erika; Miyata, Saori; Kato, Akihito; Tateyama, Akito; Furihata, Tomokazu; Shitomi, Kanako; Iwanaga, Toshihiko; Sugaya, Tsutomu

2018-01-01

Introduction The 3-dimensional scaffold plays a key role in volume and quality of repair tissue in periodontal tissue engineering therapy. We fabricated a novel 3D collagen scaffold containing carbon-based 2-dimensional layered material, named graphene oxide (GO). The aim of this study was to characterize and assess GO scaffold for periodontal tissue healing of class II furcation defects in dog. Materials and methods GO scaffolds were prepared by coating the surface of a 3D collagen sponge scaffold with GO dispersion. Scaffolds were characterized using cytotoxicity and tissue reactivity tests. In addition, GO scaffold was implanted into dog class II furcation defects and periodontal healing was investigated at 4 weeks postsurgery. Results GO scaffold exhibited low cytotoxicity and enhanced cellular ingrowth behavior and rat bone forming ability. In addition, GO scaffold stimulated healing of dog class II furcation defects. Periodontal attachment formation, including alveolar bone, periodontal ligament-like tissue, and cementum-like tissue, was significantly increased by GO scaffold implantation, compared with untreated scaffold. Conclusion The results suggest that GO scaffold is biocompatible and possesses excellent bone and periodontal tissue formation ability. Therefore, GO scaffold would be beneficial for periodontal tissue engineering therapy. PMID:29713167

Treatment of chronic desquamative gingivitis using tissue-engineered human cultured gingival epithelial sheets: a case report.

PubMed

Okuda, Kazuhiro; Momose, Manabu; Murata, Masashi; Saito, Yoshinori; lnoie, Masukazu; Shinohara, Chikara; Wolff, Larry F; Yoshie, Hiromasa

2004-04-01

Human cultured gingival epithelial sheets were used as an autologous grafting material for regenerating gingival tissue in the maxillary left and mandibular right quadrants of a patient with chronic desquamative gingivitis. Six months post-surgery in both treated areas, there were gains in keratinized gingiva and no signs of gingival inflammation compared to presurgery. In the maxillary left quadrant, preoperative histopathologic findings revealed the epithelium was separated from the connective tissue and inflammatory cells were extensive. After grafting with the gingival epithelial sheets, inflammatory cells were decreased and separation between epithelium and connective tissue was not observed. The human cultured gingival epithelial sheets fabricated using tissue engineering technology showed significant promise for gingival augmentation in periodontal therapy.

Bone Tissue Engineering: Recent Advances and Challenges

PubMed Central

Amini, Ami R.; Laurencin, Cato T.; Nukavarapu, Syam P.

2013-01-01

The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regeneration. Specifically, we discuss widely investigated biomaterial scaffolds, micro- and nano-structural properties of these scaffolds, and the incorporation of biomimetic properties and/or growth factors. In addition, we examine various cellular approaches, including the use of mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), adult stem cells, induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), and their clinical application strengths and limitations. We conclude by overviewing the challenges that face the bone tissue engineering field, such as the lack of sufficient vascularization at the defect site, and the research aimed at functional bone tissue engineering. These challenges will drive future research in the field. PMID:23339648

Low-intensity pulsed ultrasound in dentofacial tissue engineering.

PubMed

Tanaka, Eiji; Kuroda, Shingo; Horiuchi, Shinya; Tabata, Akira; El-Bialy, Tarek

2015-04-01

Oral and maxillofacial diseases affect millions of people worldwide and hence tissue engineering can be considered an interesting and clinically relevant approach to regenerate orofacial tissues after being affected by different diseases. Among several innovations for tissue regeneration, low-intensity pulsed ultrasound (LIPUS) has been used extensively in medicine as a therapeutic, operative, and diagnostic tool. LIPUS is accepted to promote bone fracture repair and regeneration. Furthermore, the effect of LIPUS on soft tissues regeneration has been paid much attention, and many studies have performed to evaluate the potential use of LIPUS to tissue engineering soft tissues. The present article provides an overview about the status of LIPUS stimulation as a tool to be used to enhance regeneration/tissue engineering. This review consists of five parts. Part 1 is a brief introduction of the acoustic description of LIPUS and mechanical action. In Part 2, biological problems in dentofacial tissue engineering are proposed. Part 3 explores biologic mechanisms of LIPUS to cells and tissues in living body. In Part 4, the effectiveness of LIPUS on cell metabolism and tissue regeneration in dentistry are summarized. Finally, Part 5 relates the possibility of clinical application of LIPUS in orthodontics. The present review brings out better understanding of the bioeffect of LIPUS therapy on orofacial tissues which is essential to the successful integration of management remedies for tissue regeneration/engineering. To develop an evidence-based approach to clinical management and treatment of orofacial degenerative diseases using LIPUS, we would like to be in full pursuit of LIPUS biotherapy. Still, there are many challenges for this relatively new strategy, but the up to date achievements using it promises to go far beyond the present possibilities.

Dental Pulp and Dentin Tissue Engineering and Regeneration – Advancement and Challenge

PubMed Central

Huang, George T.-J.

2012-01-01

Hard tissue is difficult to repair especially dental structures. Tooth enamel is incapable of self-repairing whereas dentin and cememtum can regenerate with limited capacity. Enamel and dentin are commonly under the attack by caries. Extensive forms of caries destroy enamel and dentin and can lead to dental pulp infection. Entire pulp amputation followed by the pulp space disinfection and filled with an artificial rubber-like material is employed to treat the infection --commonly known as root canal or endodontic therapy. Regeneration of dentin relies on having vital pulps; however, regeneration of pulp tissue has been difficult as the tissue is encased in dentin without collateral blood supply except from the root apical end. With the advent of modern tissue engineering concept and the discovery of dental stem cells, regeneration of pulp and dentin has been tested. This article will review the recent endeavor on pulp and dentin tissue engineering and regeneration. The prospective outcome of the current advancement and challenge in this line of research will be discussed. PMID:21196351

Carbon nanotubes: their potential and pitfalls for bone tissue regeneration and engineering.

PubMed

Newman, Peter; Minett, Andrew; Ellis-Behnke, Rutledge; Zreiqat, Hala

2013-11-01

The extracellular environment which supports cell life is composed of a hierarchy of maintenance, force and regulatory systems which integrate from the nano- through to macroscale. For this reason, strategies to recreate cell supporting environments have been investigating the use of nanocomposite biomaterials. Here, we review the use of carbon nanotubes as part of a bottom-up approach for use in bone tissue engineering. We evaluate the properties of carbon nanotubes in the context of synthetic tissue substrates and contrast them with the nanoscale features of the extracellular environment. Key studies are evaluated with an emphasis on understanding the mechanisms through which carbon nanotubes interact with biological systems. This includes an examination of how the different properties of carbon nanotubes affect tissue growth, how these properties and variation to them might be leveraged in regenerative tissue therapies and how impurities or contaminates affect their toxicity and biological interaction. In this comprehensive review, the authors describe the status and potential applications of carbon nanotubes in bone tissue engineering. © 2013.

Design and Fabrication of an MRI-Compatible, Autonomous Incubation System.

PubMed

Khalilzad-Sharghi, Vahid; Xu, Huihui

2015-10-01

Tissue engineers have long sought access to an autonomous, imaging-compatible tissue incubation system that, with minimum operator handling, can provide real-time visualization and quantification of cells, tissue constructs, and organs. This type of screening system, capable of operating noninvasively to validate tissue, can overcome current limitations like temperature shock, unsustainable cellular environments, sample contamination, and handling/stress. However, this type of system has been a major challenge, until now. Here, we describe the design, fabrication, and characterization of an innovative, autonomous incubation system that is compatible with a 9.4 T magnetic resonance imaging (MRI) scanner. Termed the e-incubator (patent pending; application number: 13/953,984), this microcontroller-based system is integrated into an MRI scanner and noninvasively screens cells and tissue cultures in an environment where temperature, pH, and media/gas handling are regulated. The 4-week study discussed herein details the continuous operation of the e-incubator for a tissue-engineered osteogenic construct, validated by LIVE/DEAD(®) cell assays and histology. The evolving MR quantitative parameters of the osteogenic construct were used as biomarkers for bone tissue engineering and to further validate the quality of the product noninvasively before harvesting. Importantly, the e-incubator reliably facilitates culturing cells and tissue constructs to create engineered tissues and/or investigate disease therapies.

Bone Tissue Engineering and Regeneration: From Discovery to the Clinic—An Overview

PubMed Central

2011-01-01

A National Institutes of Health sponsored workshop “Bone Tissue Engineering and Regeneration: From Discovery to the Clinic” gathered thought leaders from medicine, science, and industry to determine the state of art in the field and to define the barriers to translating new technologies to novel therapies to treat bone defects. Tissue engineering holds enormous promise to improve human health through prevention of disease and the restoration of healthy tissue functions. Bone tissue engineering, similar to that for other tissues and organs, requires integration of multiple disciplines such as cell biology, stem cells, developmental and molecular biology, biomechanics, biomaterials science, and immunology and transplantation science. Although each of the research areas has undergone enormous advances in last decade, the translation to clinical care and the development of tissue engineering composites to replace human tissues has been limited. Bone, similar to other tissue and organs, has complex structure and functions and requires exquisite interactions between cells, matrices, biomechanical forces, and gene and protein regulatory factors for sustained function. The process of engineering bone, thus, requires a comprehensive approach with broad expertise. Although in vitro and preclinical animal studies have been pursued with a large and diverse collection of scaffolds, cells, and biomolecules, the field of bone tissue engineering remains fragmented up to the point that a clear translational roadmap has yet to emerge. Translation is particularly important for unmet clinical needs such as large segmental defects and medically compromised conditions such as tumor removal and infection sites. Collectively, manuscripts in this volume provide luminary examples toward identification of barriers and strategies for translation of fundamental discoveries into clinical therapeutics. PMID:21902614

Bone tissue engineering and regeneration: from discovery to the clinic--an overview.

PubMed

O'Keefe, Regis J; Mao, Jeremy

2011-12-01

A National Institutes of Health sponsored workshop "Bone Tissue Engineering and Regeneration: From Discovery to the Clinic" gathered thought leaders from medicine, science, and industry to determine the state of art in the field and to define the barriers to translating new technologies to novel therapies to treat bone defects. Tissue engineering holds enormous promise to improve human health through prevention of disease and the restoration of healthy tissue functions. Bone tissue engineering, similar to that for other tissues and organs, requires integration of multiple disciplines such as cell biology, stem cells, developmental and molecular biology, biomechanics, biomaterials science, and immunology and transplantation science. Although each of the research areas has undergone enormous advances in last decade, the translation to clinical care and the development of tissue engineering composites to replace human tissues has been limited. Bone, similar to other tissue and organs, has complex structure and functions and requires exquisite interactions between cells, matrices, biomechanical forces, and gene and protein regulatory factors for sustained function. The process of engineering bone, thus, requires a comprehensive approach with broad expertise. Although in vitro and preclinical animal studies have been pursued with a large and diverse collection of scaffolds, cells, and biomolecules, the field of bone tissue engineering remains fragmented up to the point that a clear translational roadmap has yet to emerge. Translation is particularly important for unmet clinical needs such as large segmental defects and medically compromised conditions such as tumor removal and infection sites. Collectively, manuscripts in this volume provide luminary examples toward identification of barriers and strategies for translation of fundamental discoveries into clinical therapeutics. © Mary Ann Liebert, Inc.

The implications of recent advances in carboxymethyl chitosan based targeted drug delivery and tissue engineering applications.

PubMed

Upadhyaya, Laxmi; Singh, Jay; Agarwal, Vishnu; Tewari, Ravi Prakash

2014-07-28

Over the last decade carboxymethyl chitosan (CMCS) has emerged as a promising biopolymer for the development of new drug delivery systems and improved scaffolds along with other tissue engineering devices for regenerative medicine that is currently one of the most rapidly growing fields in the life sciences. CMCS is amphiprotic ether, derived from chitosan, exhibiting enhanced aqueous solubility, excellent biocompatibility, controllable biodegradability, osteogenesis ability and numerous other outstanding physicochemical and biological properties. More strikingly, it can load hydrophobic drugs and displays strong bioactivity which highlight its suitability and extensive usage for preparing different drug delivery and tissue engineering formulations respectively. This review provides a comprehensive introduction to various types of CMCS based formulations for delivery of therapeutic agents and tissue regeneration and further describes their preparation procedures and applications in different tissues/organs. Detailed information of CMCS based nano/micro systems for targeted delivery of drugs with emphasis on cancer specific and organ specific drug delivery have been described. Further, we have discussed various CMCS based tissue engineering biomaterials along with their preparation procedures and applications in different tissues/organs. The article then, gives a brief account of therapy combining drug delivery and tissue engineering. Finally, identification of major challenges and opportunities for current and ongoing application of CMCS based systems in the field are summarised. Copyright © 2014 Elsevier B.V. All rights reserved.

Clinical Translation of Cell Therapy, Tissue Engineering, and Regenerative Medicine Product in Malaysia and Its Regulatory Policy.

PubMed

Bt Hj Idrus, Ruszymah; Abas, Arpah; Ab Rahim, Fazillahnor; Saim, Aminuddin Bin

2015-12-01

With the worldwide growth of cell and tissue therapy (CTT) in treating diseases, the need of a standardized regulatory policy is of paramount concern. Research in CTT in Malaysia has reached stages of clinical trials and commercialization. In Malaysia, the regulation of CTT is under the purview of the National Pharmaceutical Control Bureau (NPCB), Ministry of Health (MOH). NPCB is given the task of regulating CTT, under a new Cell and Gene Therapy Products framework, and the guidelines are currently being formulated. Apart from the laboratory accreditation, researchers are advised to follow Guidelines for Stem Cell Research and Therapy from the Medical Development Division, MOH, published in 2009.

Clinical Translation of Cell Therapy, Tissue Engineering, and Regenerative Medicine Product in Malaysia and Its Regulatory Policy

PubMed Central

Abas, Arpah; Ab Rahim, Fazillahnor; Saim, Aminuddin Bin

2015-01-01

With the worldwide growth of cell and tissue therapy (CTT) in treating diseases, the need of a standardized regulatory policy is of paramount concern. Research in CTT in Malaysia has reached stages of clinical trials and commercialization. In Malaysia, the regulation of CTT is under the purview of the National Pharmaceutical Control Bureau (NPCB), Ministry of Health (MOH). NPCB is given the task of regulating CTT, under a new Cell and Gene Therapy Products framework, and the guidelines are currently being formulated. Apart from the laboratory accreditation, researchers are advised to follow Guidelines for Stem Cell Research and Therapy from the Medical Development Division, MOH, published in 2009. PMID:26192075

Development of Causative Treatment Strategies for Lacrimal Gland Insufficiency by Tissue Engineering and Cell Therapy. Part 2: Reconstruction of Lacrimal Gland Tissue: What Has Been Achieved So Far and What Are the Remaining Challenges?

PubMed

Massie, Isobel; Dietrich, Jana; Roth, Mathias; Geerling, Gerd; Mertsch, Sonja; Schrader, Stefan

2016-10-01

The lacrimal gland is located in the upper temporal compartment of the orbita, and along with the ocular surface, eye lids, and sensory and motor nerves forms the lacrimal functional unit (LFU). The LFU is responsible for producing, distributing, and maintaining the tear film in order to maintain a smooth, moist, and regular ocular surface epithelium such that appropriate refractive properties are achieved and the eyeball is protected against dust, debris, and pathogens. If the main lacrimal gland is impaired (due to either disease or injury), this balance is disrupted, and severe quantitative dry eye syndrome (DES) can develop. DES treatments remain palliative, with the most commonly used therapies being based on tear substitution, tear retention, and control of inflammation on the ocular surface. Causative treatments such as salivary gland transplantation have shown to reduce symptoms in very severe cases, however can cause problems on the ocular surface due to different properties of saliva and tears. Therefore, causative approaches for treating DES by regeneration or reconstruction of lacrimal gland tissue depending on disease severity seem highly appealing. This article reviews current approaches for in vitro reconstruction of lacrimal gland tissue. Finally, the limitations that must be overcome before a new, tissue-engineered therapy may be delivered to clinic will be discussed.

Current Advancements and Strategies in Tissue Engineering for Wound Healing: A Comprehensive Review.

PubMed

Ho, Jasmine; Walsh, Claire; Yue, Dominic; Dardik, Alan; Cheema, Umber

2017-06-01

Significance: With an aging population leading to an increase in diabetes and associated cutaneous wounds, there is a pressing clinical need to improve wound-healing therapies. Recent Advances: Tissue engineering approaches for wound healing and skin regeneration have been developed over the past few decades. A review of current literature has identified common themes and strategies that are proving successful within the field: The delivery of cells, mainly mesenchymal stem cells, within scaffolds of the native matrix is one such strategy. We overview these approaches and give insights into mechanisms that aid wound healing in different clinical scenarios. Critical Issues: We discuss the importance of the biomimetic niche, and how recapitulating elements of the native microenvironment of cells can help direct cell behavior and fate. Future Directions: It is crucial that during the continued development of tissue engineering in wound repair, there is close collaboration between tissue engineers and clinicians to maintain the translational efficacy of this approach.

Current Advancements and Strategies in Tissue Engineering for Wound Healing: A Comprehensive Review

PubMed Central

Ho, Jasmine; Walsh, Claire; Yue, Dominic; Dardik, Alan; Cheema, Umber

2017-01-01

Significance: With an aging population leading to an increase in diabetes and associated cutaneous wounds, there is a pressing clinical need to improve wound-healing therapies. Recent Advances: Tissue engineering approaches for wound healing and skin regeneration have been developed over the past few decades. A review of current literature has identified common themes and strategies that are proving successful within the field: The delivery of cells, mainly mesenchymal stem cells, within scaffolds of the native matrix is one such strategy. We overview these approaches and give insights into mechanisms that aid wound healing in different clinical scenarios. Critical Issues: We discuss the importance of the biomimetic niche, and how recapitulating elements of the native microenvironment of cells can help direct cell behavior and fate. Future Directions: It is crucial that during the continued development of tissue engineering in wound repair, there is close collaboration between tissue engineers and clinicians to maintain the translational efficacy of this approach. PMID:28616360

Tissue-engineered thyroid cell sheet rescued hypothyroidism in rat models after receiving total thyroidectomy comparing with nontransplantation models.

PubMed

Arauchi, Ayumi; Shimizu, Tatsuya; Yamato, Masayuki; Obara, Takao; Okano, Teruo

2009-12-01

For hormonal deficiency caused by endocrine organ diseases, continuous oral hormone administration is indispensable to supplement the shortage of hormones. In this study, as a more effective therapy, we have tried to reconstruct the three-dimensional thyroid tissue by the cell sheet technology, a novel tissue engineering approach. The cell suspension obtained from rat thyroid gland was cultured on temperature-responsive culture dishes, from which confluent cells detach as a cell sheet simply by reducing temperature without any enzymatic treatment. The 8-week-old Lewis rats were exposed to total thyroidectomy as hypothyroidism models and received thyroid cell sheet transplantation 1 week after total thyroidectomy. Serum levels of free triiodothyronine (fT(3)) and free thyroxine (fT(4)) significantly decreased 1 week after total thyroidectomy. On the other hand, transplantation of the thyroid cell sheets was able to restore the thyroid function 1 week after the cell sheet transplantation, and improvement was maintained for 4 weeks. Moreover, morphological analyses showed typical thyroid follicle organization, and anti-thyroid-transcription-factor-1 antibody staining demonstrated the presence of follicle epithelial cells. The presence of functional microvessels was also detected within the engineered thyroid tissues. In conclusion, our results indicate that thyroid cell sheets transplanted in a model of total thyroidectomy can reorganize histologically to resemble a typical thyroid gland and restore thyroid function in vivo. In this study, we are the first to confirm that engineered thyroid tissue can repair hypothyroidism models in rats and, therefore, cell sheet transplantation of endocrine organs may be suitable for the therapy of hormonal deficiency.

Cardiac Conduction through Engineered Tissue

PubMed Central

Choi, Yeong-Hoon; Stamm, Christof; Hammer, Peter E.; Kwaku, Kevin F.; Marler, Jennifer J.; Friehs, Ingeborg; Jones, Mara; Rader, Christine M.; Roy, Nathalie; Eddy, Mau-Thek; Triedman, John K.; Walsh, Edward P.; McGowan, Francis X.; del Nido, Pedro J.; Cowan, Douglas B.

2006-01-01

In children, interruption of cardiac atrioventricular (AV) electrical conduction can result from congenital defects, surgical interventions, and maternal autoimmune diseases during pregnancy. Complete AV conduction block is typically treated by implanting an electronic pacemaker device, although long-term pacing therapy in pediatric patients has significant complications. As a first step toward developing a substitute treatment, we implanted engineered tissue constructs in rat hearts to create an alternative AV conduction pathway. We found that skeletal muscle-derived cells in the constructs exhibited sustained electrical coupling through persistent expression and function of gap junction proteins. Using fluorescence in situ hybridization and polymerase chain reaction analyses, myogenic cells in the constructs were shown to survive in the AV groove of implanted hearts for the duration of the animal’s natural life. Perfusion of hearts with fluorescently labeled lectin demonstrated that implanted tissues became vascularized and immunostaining verified the presence of proteins important in electromechanical integration of myogenic cells with surrounding recipient rat cardiomyocytes. Finally, using optical mapping and electrophysiological analyses, we provide evidence of permanent AV conduction through the implant in one-third of recipient animals. Our experiments provide a proof-of-principle that engineered tissue constructs can function as an electrical conduit and, ultimately, may offer a substitute treatment to conventional pacing therapy. PMID:16816362

Remote Control of Tissue Interactions via Engineered Photo-switchable Cell Surfaces

NASA Astrophysics Data System (ADS)

Luo, Wei; Pulsipher, Abigail; Dutta, Debjit; Lamb, Brian M.; Yousaf, Muhammad N.

2014-09-01

We report a general cell surface molecular engineering strategy via liposome fusion delivery to create a dual photo-active and bio-orthogonal cell surface for remote controlled spatial and temporal manipulation of microtissue assembly and disassembly. Cell surface tailoring of chemoselective functional groups was achieved by a liposome fusion delivery method and quantified by flow cytometry and characterized by a new cell surface lipid pull down mass spectrometry strategy. Dynamic co-culture spheroid tissue assembly in solution and co-culture tissue multilayer assembly on materials was demonstrated by an intercellular photo-oxime ligation that could be remotely cleaved and disassembled on demand. Spatial and temporal control of microtissue structures containing multiple cell types was demonstrated by the generation of patterned multilayers for controlling stem cell differentiation. Remote control of cell interactions via cell surface engineering that allows for real-time manipulation of tissue dynamics may provide tools with the scope to answer fundamental questions of cell communication and initiate new biotechnologies ranging from imaging probes to drug delivery vehicles to regenerative medicine, inexpensive bioreactor technology and tissue engineering therapies.

Induction of angiogenesis in tissue-engineered scaffolds designed for bone repair: a combined gene therapy-cell transplantation approach.

PubMed

Jabbarzadeh, Ehsan; Starnes, Trevor; Khan, Yusuf M; Jiang, Tao; Wirtel, Anthony J; Deng, Meng; Lv, Qing; Nair, Lakshmi S; Doty, Steven B; Laurencin, Cato T

2008-08-12

One of the fundamental principles underlying tissue engineering approaches is that newly formed tissue must maintain sufficient vascularization to support its growth. Efforts to induce vascular growth into tissue-engineered scaffolds have recently been dedicated to developing novel strategies to deliver specific biological factors that direct the recruitment of endothelial cell (EC) progenitors and their differentiation. The challenge, however, lies in orchestration of the cells, appropriate biological factors, and optimal factor doses. This study reports an approach as a step forward to resolving this dilemma by combining an ex vivo gene transfer strategy and EC transplantation. The utility of this approach was evaluated by using 3D poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds for bone tissue engineering applications. Our goal was achieved by isolation and transfection of adipose-derived stromal cells (ADSCs) with adenovirus encoding the cDNA of VEGF. We demonstrated that the combination of VEGF releasing ADSCs and ECs results in marked vascular growth within PLAGA scaffolds. We thereby delineate the potential of ADSCs to promote vascular growth into biomaterials.

Recent advances in gene-enhanced bone tissue engineering.

PubMed

Betz, Volker M; Kochanek, Stefan; Rammelt, Stefan; Müller, Peter E; Betz, Oliver B; Messmer, Carolin

2018-03-30

The loss of bone tissue represents a critical clinical condition that is frequently faced by surgeons. Substantial progress has been made in the area of bone research, providing insight into the biology of bone under physiological and pathological conditions, as well as tools for the stimulation of bone regeneration. The present review discusses recent advances in the field of gene-enhanced bone tissue engineering. Gene transfer strategies have emerged as highly effective tissue engineering approaches for supporting the repair of the musculoskeletal system. By contrast to treatment with recombinant proteins, genetically engineered cells can release growth factors at the site of injury over extended periods of time. Of particular interest are the expedited technologies that can be applied during a single surgical procedure in a cost-effective manner, allowing translation from bench to bedside. Several promising methods based on the intra-operative genetic manipulation of autologous cells or tissue fragments have been developed in preclinical studies. Moreover, gene therapy for bone regeneration has entered the clinical stage with clinical trials for the repair of alveolar bone. Current trends in gene-enhanced bone engineering are also discussed with respect to the movement of the field towards expedited, translational approaches. It is possible that gene-enhanced bone tissue engineering will become a clinical reality within the next few years. Copyright © 2018 John Wiley & Sons, Ltd.

Introduction to regenerative medicine and tissue engineering.

PubMed

Stoltz, J-F; Decot, V; Huseltein, C; He, X; Zhang, L; Magdalou, J; Li, Y P; Menu, P; Li, N; Wang, Y Y; de Isla, N; Bensoussan, D

2012-01-01

Human tissues don't regenerate spontaneously, explaining why regenerative medicine and cell therapy represent a promising alternative treatment (autologous cells or stem cells of different origins). The principle is simple: cells are collected, expanded and introduced with or without modification into injured tissues or organs. Among middle-term therapeutic applications, cartilage defects, bone repair, cardiac insufficiency, burns, liver or bladder, neurodegenerative disorders could be considered.

MicroRNAs in vascular tissue engineering and post-ischemic neovascularization☆

PubMed Central

Caputo, Massimo; Saif, Jaimy; Rajakaruna, Cha; Brooks, Marcus; Angelini, Gianni D.; Emanueli, Costanza

2015-01-01

Increasing numbers of paediatric patients with congenital heart defects are surviving to adulthood, albeit with continuing clinical needs. Hence, there is still scope for revolutionary new strategies to correct vascular anatomical defects. Adult patients are also surviving longer with the adverse consequences of ischemic vascular disease, especially after acute coronary syndromes brought on by plaque erosion and rupture. Vascular tissue engineering and therapeutic angiogenesis provide new hope for these patients. Both approaches have shown promise in laboratory studies, but have not yet been able to deliver clear evidence of clinical success. More research into biomaterials, molecular medicine and cell and molecular therapies is necessary. This review article focuses on the new opportunities offered by targeting microRNAs for the improved production and greater empowerment of vascular cells for use in vascular tissue engineering or for increasing blood perfusion of ischemic tissues by amplifying the resident microvascular network. PMID:25980937

Chitosan for gene delivery and orthopedic tissue engineering applications.

PubMed

Raftery, Rosanne; O'Brien, Fergal J; Cryan, Sally-Ann

2013-05-15

Gene therapy involves the introduction of foreign genetic material into cells in order exert a therapeutic effect. The application of gene therapy to the field of orthopaedic tissue engineering is extremely promising as the controlled release of therapeutic proteins such as bone morphogenetic proteins have been shown to stimulate bone repair. However, there are a number of drawbacks associated with viral and synthetic non-viral gene delivery approaches. One natural polymer which has generated interest as a gene delivery vector is chitosan. Chitosan is biodegradable, biocompatible and non-toxic. Much of the appeal of chitosan is due to the presence of primary amine groups in its repeating units which become protonated in acidic conditions. This property makes it a promising candidate for non-viral gene delivery. Chitosan-based vectors have been shown to transfect a number of cell types including human embryonic kidney cells (HEK293) and human cervical cancer cells (HeLa). Aside from its use in gene delivery, chitosan possesses a range of properties that show promise in tissue engineering applications; it is biodegradable, biocompatible, has anti-bacterial activity, and, its cationic nature allows for electrostatic interaction with glycosaminoglycans and other proteoglycans. It can be used to make nano- and microparticles, sponges, gels, membranes and porous scaffolds. Chitosan has also been shown to enhance mineral deposition during osteogenic differentiation of MSCs in vitro. The purpose of this review is to critically discuss the use of chitosan as a gene delivery vector with emphasis on its application in orthopedic tissue engineering.

Combining Gene and Stem Cell Therapy for Peripheral Nerve Tissue Engineering.

PubMed

Busuttil, Francesca; Rahim, Ahad A; Phillips, James B

2017-02-15

Despite a substantially increased understanding of neuropathophysiology, insufficient functional recovery after peripheral nerve injury remains a significant clinical challenge. Nerve regeneration following injury is dependent on Schwann cells, the supporting cells in the peripheral nervous system. Following nerve injury, Schwann cells adopt a proregenerative phenotype, which supports and guides regenerating nerves. However, this phenotype may not persist long enough to ensure functional recovery. Tissue-engineered nerve repair devices containing therapeutic cells that maintain the appropriate phenotype may help enhance nerve regeneration. The combination of gene and cell therapy is an emerging experimental strategy that seeks to provide the optimal environment for axonal regeneration and reestablishment of functional circuits. This review aims to summarize current preclinical evidence with potential for future translation from bench to bedside.

X-ray Phase Contrast Imaging of Calcified Tissue and Biomaterial Structure in Bioreactor Engineered Tissues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Appel, Alyssa A.; Larson, Jeffery C.; Garson, III, Alfred B.

2014-11-04

Tissues engineered in bioreactor systems have been used clinically to replace damaged tissues and organs. In addition, these systems are under continued development for many tissue engineering applications. The ability to quantitatively assess material structure and tissue formation is critical for evaluating bioreactor efficacy and for preimplantation assessment of tissue quality. These techniques allow for the nondestructive and longitudinal monitoring of large engineered tissues within the bioreactor systems and will be essential for the translation of these strategies to viable clinical therapies. X-ray Phase Contrast (XPC) imaging techniques have shown tremendous promise for a number of biomedical applications owing tomore » their ability to provide image contrast based on multiple X-ray properties, including absorption, refraction, and scatter. In this research, mesenchymal stem cell-seeded alginate hydrogels were prepared and cultured under osteogenic conditions in a perfusion bioreactor. The constructs were imaged at various time points using XPC microcomputed tomography (µCT). Imaging was performed with systems using both synchrotron- and tube-based X-ray sources. XPC µCT allowed for simultaneous three-dimensional (3D) quantification of hydrogel size and mineralization, as well as spatial information on hydrogel structure and mineralization. Samples were processed for histological evaluation and XPC showed similar features to histology and quantitative analysis consistent with the histomorphometry. Furthermore, these results provide evidence of the significant potential of techniques based on XPC for noninvasive 3D imaging engineered tissues grown in bioreactors.« less

Rheological Properties of Cross-Linked Hyaluronan–Gelatin Hydrogels for Tissue Engineering

PubMed Central

Vanderhooft, Janssen L.; Alcoutlabi, Mataz; Magda, Jules J.; Prestwich, Glenn D.

2009-01-01

Hydrogels that mimic the natural extracellular matrix (ECM) are used in three-dimensional cell culture, cell therapy, and tissue engineering. A semi-synthetic ECM based on cross-linked hyaluronana offers experimental control of both composition and gel stiffness. The mechanical properties of the ECM in part determine the ultimate cell phenotype. We now describe a rheological study of synthetic ECM hydrogels with storage shear moduli that span three orders of magnitude, from 11 to 3 500 Pa, a range important for engineering of soft tissues. The concentration of the chemically modified HA and the cross-linking density were the main determinants of gel stiffness. Increase in the ratio of thiol-modified gelatin reduced gel stiffness by diluting the effective concentration of the HA component. PMID:18839402

TOPICAL REVIEW: Trend report on international and Japanese standardization activities for bioceramics and tissue engineered medical products

NASA Astrophysics Data System (ADS)

Tsutsumi, Sadami

2010-02-01

Since porous and injectable bioceramics have recently been utilized often as scaffolds for bone regenerative medicine, the need for their standardization has increased. One of the standard proposals in ISO/TC150 and JIS has been a draft for characterization of the porous bioceramic scaffolds in both micro- and macro-scopic aspects. ISO/TC150/SC7 (Tissue engineered medical products) has been co-chaired by Professor J E Lemons, Department of Surgery, University of Alabama at Birmingham and Dr R Nakaoka, Division of Medical Devices, National Institute of Health Sciences, Japan. The scope of SC7 has been specified as 'Standardization for the general requirements and performance of tissue engineered medical products with the exclusion of gene therapy, transplantation and transfusion'.

Naturally derived myocardial matrix as an injectable scaffold for cardiac tissue engineering

PubMed Central

Singelyn, Jennifer M.; DeQuach, Jessica A.; Seif-Naraghi, Sonya B.; Littlefield, Robert B.; Schup-Magoffin, Pamela J.; Christman, Karen L.

2009-01-01

Myocardial tissue lacks the ability to significantly regenerate itself following a myocardial infarction, thus tissue engineering strategies are required for repair. Several injectable materials have been examined for cardiac tissue engineering; however, none have been designed specifically to mimic the myocardium. The goal of this study was to investigate the in vitro properties and in vivo potential of an injectable myocardial matrix designed to mimic the natural myocardial extracellular environment. Porcine myocardial tissue was decellularized and processed to form a myocardial matrix with the ability to gel in vitro at 37°C and in vivo upon injection into rat myocardium. The resulting myocardial matrix maintained a complex composition, including glycosaminoglycan content, and was able to self-assemble to form a nanofibrous structure. Endothelial cells and smooth muscle cells were shown to migrate towards the myocardial matrix both in vitro and in vivo, with a significant increase in arteriole formation at 11 days post-injection. The matrix was also successfully pushed through a clinically used catheter, demonstrating its potential for minimally invasive therapy. Thus, we have demonstrated the initial feasibility and potential of a naturally derived myocardial matrix as an injectable scaffold for cardiac tissue engineering. PMID:19608268

Development of biomaterial scaffold for nerve tissue engineering: Biomaterial mediated neural regeneration

PubMed Central

2009-01-01

Neural tissue repair and regeneration strategies have received a great deal of attention because it directly affects the quality of the patient's life. There are many scientific challenges to regenerate nerve while using conventional autologous nerve grafts and from the newly developed therapeutic strategies for the reconstruction of damaged nerves. Recent advancements in nerve regeneration have involved the application of tissue engineering principles and this has evolved a new perspective to neural therapy. The success of neural tissue engineering is mainly based on the regulation of cell behavior and tissue progression through the development of a synthetic scaffold that is analogous to the natural extracellular matrix and can support three-dimensional cell cultures. As the natural extracellular matrix provides an ideal environment for topographical, electrical and chemical cues to the adhesion and proliferation of neural cells, there exists a need to develop a synthetic scaffold that would be biocompatible, immunologically inert, conducting, biodegradable, and infection-resistant biomaterial to support neurite outgrowth. This review outlines the rationale for effective neural tissue engineering through the use of suitable biomaterials and scaffolding techniques for fabrication of a construct that would allow the neurons to adhere, proliferate and eventually form nerves. PMID:19939265

European research and commercialisation activities in the field of tissue engineering and liver support in world wide competition.

PubMed

Marx, U; Bushnaq, H; Yalcin, E

1998-02-01

Tissue engineering is seen as an interesting field of technology which could improve medical therapy and could also be considered as a commercial opportunity for the European biotechnological industry. Research in the state of the art of science using the MedLine and the Science Citation Index databases, in the patent situation and of the industry dealing with tissue engineering was done. A special method, based on the Science Citation Index Journal Citation Report 1993, for evaluating scientific work was defined. The main countries working in the field of tissue engineering were evaluated in regard to their scientific performance and their patents. The R&D of German industry was investigated as an exemplary European country. Out of all activities, different tissues were rated with respect to the attention received from research and industry and with regard to the frequency in which patents were applied for. USA, Germany and Japan rank first in most tissues, especially liver. After comparing German patents with the German scientific and industrial work, it seems that the potential in German patents and research is underestimated by German industry and inefficiently exploited.

Strategies to improve homing of mesenchymal stem cells for greater efficacy in stem cell therapy.

PubMed

Naderi-Meshkin, Hojjat; Bahrami, Ahmad Reza; Bidkhori, Hamid Reza; Mirahmadi, Mahdi; Ahmadiankia, Naghmeh

2015-01-01

Stem/progenitor cell-based therapeutic approach in clinical practice has been an elusive dream in medical sciences, and improvement of stem cell homing is one of major challenges in cell therapy programs. Stem/progenitor cells have a homing response to injured tissues/organs, mediated by interactions of chemokine receptors expressed on the cells and chemokines secreted by the injured tissue. For improvement of directed homing of the cells, many techniques have been developed either to engineer stem/progenitor cells with higher amount of chemokine receptors (stem cell-based strategies) or to modulate the target tissues to release higher level of the corresponding chemokines (target tissue-based strategies). This review discusses both of these strategies involved in the improvement of stem cell homing focusing on mesenchymal stem cells as most frequent studied model in cellular therapies. © 2014 International Federation for Cell Biology.

Nanotechnology for regenerative medicine.

PubMed

Khang, Dongwoo; Carpenter, Joseph; Chun, Young Wook; Pareta, Rajesh; Webster, Thomas J

2010-08-01

Future biomaterials must simultaneously enhance tissue regeneration while minimizing immune responses and inhibiting infection. While the field of tissue engineering has promised to develop materials that can promote tissue regeneration for the entire body, such promises have not become reality. However, tissue engineering has experienced great progress due to the recent emergence of nanotechnology. Specifically, it has now been well established that increased tissue regeneration can be achieved on almost any surface by employing novel nano-textured surface features. Numerous studies have reported that nanotechnology accelerates various regenerative therapies, such as those for the bone, vascular, heart, cartilage, bladder and brain tissue. Various nano-structured polymers and metals (alloys) have been investigated for their bio (and cyto) compatibility properties. This review paper discusses several of the latest nanotechnology findings in regenerative medicine (also now called nanomedicine) as well as their relative levels of success.

Current Treatment Limitations in Age-Related Macular Degeneration and Future Approaches Based on Cell Therapy and Tissue Engineering

PubMed Central

Fernández-Robredo, P.; Sancho, A.; Johnen, S.; Recalde, S.; Gama, N.; Thumann, G.; Groll, J.; García-Layana, A.

2014-01-01

Age-related macular degeneration (AMD) is the leading cause of blindness in the Western world. With an ageing population, it is anticipated that the number of AMD cases will increase dramatically, making a solution to this debilitating disease an urgent requirement for the socioeconomic future of the European Union and worldwide. The present paper reviews the limitations of the current therapies as well as the socioeconomic impact of the AMD. There is currently no cure available for AMD, and even palliative treatments are rare. Treatment options show several side effects, are of high cost, and only treat the consequence, not the cause of the pathology. For that reason, many options involving cell therapy mainly based on retinal and iris pigment epithelium cells as well as stem cells are being tested. Moreover, tissue engineering strategies to design and manufacture scaffolds to mimic Bruch's membrane are very diverse and under investigation. Both alternative therapies are aimed to prevent and/or cure AMD and are reviewed herein. PMID:24672707

Controlling tissue microenvironments: biomimetics, transport phenomena, and reacting systems.

PubMed

Fisher, Robert J; Peattie, Robert A

2007-01-01

The reconstruction of tissues ex vivo and production of cells capable of maintaining a stable performance for extended time periods in sufficient quantity for synthetic or therapeutic purposes are primary objectives of tissue engineering. The ability to characterize and manipulate the cellular microenvironment is critical for successful implementation of such cell-based bioengineered systems. As a result, knowledge of fundamental biomimetics, transport phenomena, and reaction engineering concepts is essential to system design and development. Once the requirements of a specific tissue microenvironment are understood, the biomimetic system specifications can be identified and a design implemented. Utilization of novel membrane systems that are engineered to possess unique transport and reactive features is one successful approach presented here. The limited availability of tissue or cells for these systems dictates the need for microscale reactors. A capstone illustration based on cellular therapy for type 1 diabetes mellitus via encapsulation techniques is presented as a representative example of this approach, to stress the importance of integrated systems.

Methacrylated gelatin/hyaluronan-based hydrogels for soft tissue engineering

PubMed Central

Kessler, Lukas; Gehrke, Sandra; Winnefeld, Marc; Huber, Birgit; Hoch, Eva; Walter, Torsten; Wyrwa, Ralf; Schnabelrauch, Matthias; Schmidt, Malte; Kückelhaus, Maximilian; Lehnhardt, Marcus; Hirsch, Tobias; Jacobsen, Frank

2017-01-01

In vitro–generated soft tissue could provide alternate therapies for soft tissue defects. The aim of this study was to evaluate methacrylated gelatin/hyaluronan as scaffolds for soft tissue engineering and their interaction with human adipose–derived stem cells (hASCs). ASCs were incorporated into methacrylated gelatin/hyaluronan hydrogels. The gels were photocrosslinked with a lithium phenyl-2,4,6-trimethylbenzoylphosphinate photoinitiator and analyzed for cell viability and adipogenic differentiation of ASCs over a period of 30 days. Additionally, an angiogenesis assay was performed to assess their angiogenic potential. After 24 h, ASCs showed increased viability on composite hydrogels. These results were consistent over 21 days of culture. By induction of adipogenic differentiation, the mature adipocytes were observed after 7 days of culture, their number significantly increased until day 28 as well as expression of fatty acid binding protein 4 and adiponectin. Our scaffolds are promising as building blocks for adipose tissue engineering and allowed long viability, proliferation, and differentiation of ASCs. PMID:29318000

The deposition of thin titanium-nitrogen coatings on the surface of PCL-based scaffolds for vascular tissue engineering

NASA Astrophysics Data System (ADS)

Kudryavtseva, Valeriya; Stankevich, Ksenia; Kibler, Elina; Golovkin, Alexey; Mishanin, Alexander; Bolbasov, Evgeny; Choynzonov, Evgeny; Tverdokhlebov, Sergei

2018-04-01

Biodegradable polymer scaffolds for tissue engineering is a promising technology for therapies of patients suffering from the loss of tissue or its function including cardiac tissues. However, limitations such as hydrophobicity of polymers prevent cell attachment, cell conductivity, and endothelialization. Plasma modification of polymers allows producing materials for an impressive range of applications due to their unique properties. Here, we demonstrate the possibility of bioresorbable electrospun polycaprolacton (PCL) scaffold surface modification by reactive magnetron sputtering of the titanium target in a nitrogen atmosphere. The influence of the plasma treatment time on the structure and properties of electrospun PCL scaffolds was studied. We show that the plasma treatment does not change the physico-mechanical properties of electrospun PCL scaffolds, leads to an increase in PCL scaffold biocompatibility, and, simultaneously, increases their hydrophilicity. In conclusion, this modification method opens a route to producing scaffolds with enhanced biocompatibility for tissue engineered vascular grafts.

Tissue engineering, stem cells and cloning: current concepts and changing trends.

PubMed

Atala, Anthony

2005-07-01

Organ damage or loss can occur from congenital disorders, cancer, trauma, infection, inflammation, iatrogenic injuries or other conditions and often necessitates reconstruction or replacement. Replacement may take the form of organ transplant. At present, there is a severe shortage of donor organs that is worsening with the aging of the population. Tissue engineering follows the principles of cell transplantation, materials science and engineering towards the development of biological substitutes that can restore and maintain normal tissue function. Therapeutic cloning involves the introduction of a nucleus from a donor cell into an enucleated oocyte to generate embryonic stem cell lines whose genetic material is identical to that of its source. These autologous stem cells have the potential to become almost any type of cell in the adult body, and thus would be useful in tissue and organ replacement applications. This paper reviews recent advances in stem cell research and regenerative medicine, and describes the clinical applications of these technologies as novel therapies for tissue or organ loss.

In Vitro Engineering of Vascularized Tissue Surrogates

PubMed Central

Sakaguchi, Katsuhisa; Shimizu, Tatsuya; Horaguchi, Shigeto; Sekine, Hidekazu; Yamato, Masayuki; Umezu, Mitsuo; Okano, Teruo

2013-01-01

In vitro scaling up of bioengineered tissues is known to be limited by diffusion issues, specifically a lack of vasculature. Here, we report a new strategy for preserving cell viability in three-dimensional tissues using cell sheet technology and a perfusion bioreactor having collagen-based microchannels. When triple-layer cardiac cell sheets are incubated within this bioreactor, endothelial cells in the cell sheets migrate to vascularize in the collagen gel, and finally connect with the microchannels. Medium readily flows into the cell sheets through the microchannels and the newly developed capillaries, while the cardiac construct shows simultaneous beating. When additional triple-layer cell sheets are repeatedly layered, new multi-layer construct spontaneously integrates and the resulting construct becomes a vascularized thick tissue. These results confirmed our method to fabricate in vitro vascularized tissue surrogates that overcomes engineered-tissue thickness limitations. The surrogates promise new therapies for damaged organs as well as new in vitro tissue models. PMID:23419835

Cryopreserved Dental Pulp Tissues of Exfoliated Deciduous Teeth Is a Feasible Stem Cell Resource for Regenerative Medicine

PubMed Central

Yamaza, Haruyoshi; Akiyama, Kentaro; Hoshino, Yoshihiro; Song, Guangtai; Kukita, Toshio; Nonaka, Kazuaki; Shi, Songtao; Yamaza, Takayoshi

2012-01-01

Human exfoliated deciduous teeth have been considered to be a promising source for regenerative therapy because they contain unique postnatal stem cells from human exfoliated deciduous teeth (SHED) with self-renewal capacity, multipotency and immunomodulatory function. However preservation technique of deciduous teeth has not been developed. This study aimed to evaluate that cryopreserved dental pulp tissues of human exfoliated deciduous teeth is a retrievable and practical SHED source for cell-based therapy. SHED isolated from the cryopreserved deciduous pulp tissues for over 2 years (25–30 months) (SHED-Cryo) owned similar stem cell properties including clonogenicity, self-renew, stem cell marker expression, multipotency, in vivo tissue regenerative capacity and in vitro immunomodulatory function to SHED isolated from the fresh tissues (SHED-Fresh). To examine the therapeutic efficacy of SHED-Cryo on immune diseases, SHED-Cryo were intravenously transplanted into systemic lupus erythematosus (SLE) model MRL/lpr mice. Systemic SHED-Cryo-transplantation improved SLE-like disorders including short lifespan, elevated autoantibody levels and nephritis-like renal dysfunction. SHED-Cryo amended increased interleukin 17-secreting helper T cells in MRL/lpr mice systemically and locally. SHED-Cryo-transplantation was also able to recover osteoporosis bone reduction in long bones of MRL/lpr mice. Furthermore, SHED-Cryo-mediated tissue engineering induced bone regeneration in critical calvarial bone-defect sites of immunocompromised mice. The therapeutic efficacy of SHED-Cryo transplantation on immune and skeletal disorders was similar to that of SHED-Fresh. These data suggest that cryopreservation of dental pulp tissues of deciduous teeth provide a suitable and desirable approach for stem cell-based immune therapy and tissue engineering in regenerative medicine. PMID:23251621

Gene therapy in periodontics

PubMed Central

Chatterjee, Anirban; Singh, Nidhi; Saluja, Mini

2013-01-01

GENES are made of DNA - the code of life. They are made up of two types of base pair from different number of hydrogen bonds AT, GC which can be turned into instruction. Everyone inherits genes from their parents and passes them on in turn to their children. Every person's genes are different, and the changes in sequence determine the inherited differences between each of us. Some changes, usually in a single gene, may cause serious diseases. Gene therapy is ‘the use of genes as medicine’. It involves the transfer of a therapeutic or working gene copy into specific cells of an individual in order to repair a faulty gene copy. Thus it may be used to replace a faulty gene, or to introduce a new gene whose function is to cure or to favorably modify the clinical course of a condition. It has a promising era in the field of periodontics. Gene therapy has been used as a mode of tissue engineering in periodontics. The tissue engineering approach reconstructs the natural target tissue by combining four elements namely: Scaffold, signaling molecules, cells and blood supply and thus can help in the reconstruction of damaged periodontium including cementum, gingival, periodontal ligament and bone. PMID:23869119

Gene therapy in periodontics.

PubMed

Chatterjee, Anirban; Singh, Nidhi; Saluja, Mini

2013-03-01

GENES are made of DNA - the code of life. They are made up of two types of base pair from different number of hydrogen bonds AT, GC which can be turned into instruction. Everyone inherits genes from their parents and passes them on in turn to their children. Every person's genes are different, and the changes in sequence determine the inherited differences between each of us. Some changes, usually in a single gene, may cause serious diseases. Gene therapy is 'the use of genes as medicine'. It involves the transfer of a therapeutic or working gene copy into specific cells of an individual in order to repair a faulty gene copy. Thus it may be used to replace a faulty gene, or to introduce a new gene whose function is to cure or to favorably modify the clinical course of a condition. It has a promising era in the field of periodontics. Gene therapy has been used as a mode of tissue engineering in periodontics. The tissue engineering approach reconstructs the natural target tissue by combining four elements namely: Scaffold, signaling molecules, cells and blood supply and thus can help in the reconstruction of damaged periodontium including cementum, gingival, periodontal ligament and bone.

A human osteoarthritis osteochondral organ culture model for cartilage tissue engineering.

PubMed

Yeung, P; Zhang, W; Wang, X N; Yan, C H; Chan, B P

2018-04-01

In vitro human osteoarthritis (OA)-mimicking models enabling pathophysiological studies and evaluation of emerging therapies such as cartilage tissue engineering are of great importance. We describe the development and characterization of a human OA osteochondral organ culture. We also apply this model for evaluation of the phenotype maintenance of a human MSC derived engineered cartilage, as an example of emerging therapeutics, under long term exposure to the OA-mimicking environment. We also test the sensitivity of the model to a series of external factors and a potential disease-modifying agent, in terms of chondrogenic phenotype maintenance of the engineered cartilage, under OA-mimicking environment. Excised joint tissues from total knee replacement surgeries were carved into numerous miniaturized and standardized osteochondral plugs for subsequent OA organ culture. The organ cultures were characterized in detail before being co-cultured with a tissue engineered cartilage. The chondrogenic phenotype of the tissue engineered cartilage co-cultured in long term up to 8 weeks under this OA-mimicking microenvironment was evaluated. Using the same co-culture model, we also screened for a number of biomimetic environmental factors, including oxygen tension, the presence of serum and the application of compression loading. Finally, we studied the effect of a matrix metalloprotease inhibitor, as an example of potential disease-modifying agents, on the co-cultured engineered cartilage. We demonstrate that cells in the OA organ culture were viable while both the typical chondrogenic phenotype and the characteristic OA phenotype were maintained for long period of time. We then demonstrate that upon co-culture with the OA-mimicking organ culture, the engineered cartilage initially exhibited a more fibrocartilage phenotype but progressively reverted back to the chondrogenic phenotype upon long term co-culture up to 8 weeks. The engineered cartilage was also found to be sensitive to all biomimetic environmental factors screened (oxygen tension, serum and compression). Moreover, under the effect of a MMP inhibitor, the chondrogenic phenotype of engineered cartilage was better maintained. We demonstrated the development of a human OA osteochondral organ culture and tested the feasibility and potential of using this model as an in vitro evaluation tool for emerging cartilage therapies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Stem cell technology for tendon regeneration: current status, challenges, and future research directions

PubMed Central

Lui, Pauline Po Yee

2015-01-01

Tendon injuries are a common cause of physical disability. They present a clinical challenge to orthopedic surgeons because injured tendons respond poorly to current treatments without tissue regeneration and the time required for rehabilitation is long. New treatment options are required. Stem cell-based therapies offer great potential to promote tendon regeneration due to their high proliferative, synthetic, and immunomodulatory activities as well as their potential to differentiate to the target cell types and undergo genetic modification. In this review, I first recapped the challenges of tendon repair by reviewing the anatomy of tendon. Next, I discussed the advantages and limitations of using different types of stem cells compared to terminally differentiated cells for tendon tissue engineering. The safety and efficacy of application of stem cells and their modified counterparts for tendon tissue engineering were then summarized after a systematic literature search in PubMed. The challenges and future research directions to enhance, optimize, and standardize stem cell-based therapies for augmenting tendon repair were then discussed. PMID:26715856

Stem Cells and Scaffolds for Vascularizing Engineered Tissue Constructs

NASA Astrophysics Data System (ADS)

Luong, E.; Gerecht, S.

The clinical impact of tissue engineering depends upon our ability to direct cells to form tissues with characteristic structural and mechanical properties from the molecular level up to organized tissue. Induction and creation of functional vascular networks has been one of the main goals of tissue engineering either in vitro, for the transplantation of prevascularized constructs, or in vivo, for cellular organization within the implantation site. In most cases, tissue engineering attempts to recapitulate certain aspects of normal development in order to stimulate cell differentiation and functional tissue assembly. The induction of tissue growth generally involves the use of biodegradable and bioactive materials designed, ideally, to provide a mechanical, physical, and biochemical template for tissue regeneration. Human embryonic stem cells (hESCs), derived from the inner cell mass of a developing blastocyst, are capable of differentiating into all cell types of the body. Specifically, hESCs have the capability to differentiate and form blood vessels de novo in a process called vasculogenesis. Human ESC-derived endothelial progenitor cells (EPCs) and endothelial cells have substantial potential for microvessel formation, in vitro and in vivo. Human adult EPCs are being isolated to understand the fundamental biology of how these cells are regulated as a population and to explore whether these cells can be differentiated and reimplanted as a cellular therapy in order to arrest or even reverse damaged vasculature. This chapter focuses on advances made toward the generation and engineering of functional vascular tissue, focusing on both the scaffolds - the synthetic and biopolymer materials - and the cell sources - hESCs and hEPCs.

The influence of environmental factors on bone tissue engineering.

PubMed

Szpalski, Caroline; Sagebin, Fabio; Barbaro, Marissa; Warren, Stephen M

2013-05-01

Bone repair and regeneration are dynamic processes that involve a complex interplay between the substrate, local and systemic cells, and the milieu. Although each constituent plays an integral role in faithfully recreating the skeleton, investigators have long focused their efforts on scaffold materials and design, cytokine and hormone administration, and cell-based therapies. Only recently have the intangible aspects of the milieu received their due attention. In this review, we highlight the important influence of environmental factors on bone tissue engineering. Copyright © 2012 Wiley Periodicals, Inc.

Tissue Engineering to Improve Immature Testicular Tissue and Cell Transplantation Outcomes: One Step Closer to Fertility Restoration for Prepubertal Boys Exposed to Gonadotoxic Treatments

PubMed Central

Del Vento, Federico; de Michele, Francesca; Giudice, Maria Grazia; Poels, Jonathan; Wyns, Christine

2018-01-01

Despite their important contribution to the cure of both oncological and benign diseases, gonadotoxic therapies present the risk of a severe impairment of fertility. Sperm cryopreservation is not an option to preserve prepubertal boys’ reproductive potential, as their seminiferous tubules only contain spermatogonial stem cells (as diploid precursors of spermatozoa). Cryobanking of human immature testicular tissue (ITT) prior to gonadotoxic therapies is an accepted practice. Evaluation of cryopreserved ITT using xenotransplantation in nude mice showed the survival of a limited proportion of spermatogonia and their ability to proliferate and initiate differentiation. However, complete spermatogenesis could not be achieved in the mouse model. Loss of germ cells after ITT grafting points to the need to optimize the transplantation technique. Tissue engineering, a new branch of science that aims at improving cellular environment using scaffolds and molecules administration, might be an approach for further progress. In this review, after summarizing the lessons learned from human prepubertal testicular germ cells or tissue xenotransplantation experiments, we will focus on the benefits that might be gathered using bioengineering techniques to enhance transplantation outcomes by optimizing early tissue graft revascularization, protecting cells from toxic insults linked to ischemic injury and exploring strategies to promote cellular differentiation. PMID:29346308

Stem cells’ guided gene therapy of cancer: New frontier in personalized and targeted therapy

PubMed Central

Mavroudi, Maria; Zarogoulidis, Paul; Porpodis, Konstantinos; Kioumis, Ioannis; Lampaki, Sofia; Yarmus, Lonny; Malecki, Raf; Zarogoulidis, Konstantinos; Malecki, Marek

2014-01-01

Introduction Diagnosis and therapy of cancer remain to be the greatest challenges for all physicians working in clinical oncology and molecular medicine. The statistics speak for themselves with the grim reports of 1,638,910 men and women diagnosed with cancer and nearly 577,190 patients passed away due to cancer in the USA in 2012. For practicing clinicians, who treat patients suffering from advanced cancers with contemporary systemic therapies, the main challenge is to attain therapeutic efficacy, while minimizing side effects. Unfortunately, all contemporary systemic therapies cause side effects. In treated patients, these side effects may range from nausea to damaged tissues. In cancer survivors, the iatrogenic outcomes of systemic therapies may include genomic mutations and their consequences. Therefore, there is an urgent need for personalized and targeted therapies. Recently, we reviewed the current status of suicide gene therapy for cancer. Herein, we discuss the novel strategy: genetically engineered stem cells’ guided gene therapy. Review of therapeutic strategies in preclinical and clinical trials Stem cells have the unique potential for self renewal and differentiation. This potential is the primary reason for introducing them into medicine to regenerate injured or degenerated organs, as well as to rejuvenate aging tissues. Recent advances in genetic engineering and stem cell research have created the foundations for genetic engineering of stem cells as the vectors for delivery of therapeutic transgenes. Specifically in oncology, the stem cells are genetically engineered to deliver the cell suicide inducing genes selectively to the cancer cells only. Expression of the transgenes kills the cancer cells, while leaving healthy cells unaffected. Herein, we present various strategies to bioengineer suicide inducing genes and stem cell vectors. Moreover, we review results of the main preclinical studies and clinical trials. However, the main risk for therapeutic use of stem cells is their cancerous transformation. Therefore, we discuss various strategies to safeguard stem cell guided gene therapy against iatrogenic cancerogenesis. Perspectives Defining cancer biomarkers to facilitate early diagnosis, elucidating cancer genomics and proteomics with modern tools of next generation sequencing, and analyzing patients’ gene expression profiles provide essential data to elucidate molecular dynamics of cancer and to consider them for crafting pharmacogenomics-based personalized therapies. Streamlining of these data into genetic engineering of stem cells facilitates their use as the vectors delivering therapeutic genes into specific cancer cells. In this realm, stem cells guided gene therapy becomes a promising new frontier in personalized and targeted therapy of cancer. PMID:24860662

Bone Tissue Engineering: Past-Present-Future.

PubMed

Quarto, Rodolfo; Giannoni, Paolo

2016-01-01

Bone is one of the few tissues to display a true potential for regeneration. Fracture healing is an obvious example where regeneration occurs through tightly regulated sequences of molecular and cellular events which recapitulate tissue formation seen during embryogenesis. Still in some instances, bone regeneration does not occur properly (i.e. critical size lesions) and an appropriate therapeutic intervention is necessary. Successful replacement of bone by tissue engineering will likely depend on the recapitulation of this flow of events. In fact, bone regeneration requires cross-talk between microenvironmental factors and cells; for example, resident mesenchymal progenitors are recruited and properly guided by soluble and insoluble signaling molecules. Tissue engineering attempts to reproduce and to mimic this natural milieu by delivering cells capable of differentiating into osteoblasts, inducing growth factors and biomaterials to support cellular attachment, proliferation, migration, and matrix deposition. In the last two decades, a significant effort has been made by the scientific community in the development of methods and protocols to repair and regenerate tissues such as bone, cartilage, tendons, and ligaments. In this same period, great advancements have been achieved in the biology of stem cells and on the mechanisms governing "stemness". Unfortunately, after two decades, effective clinical translation does not exist, besides a few limited examples. Many years have passed since cell-based regenerative therapies were first described as "promising approaches", but this definition still engulfs the present literature. Failure to envisage translational cell therapy applications in routine medical practice evidences the existence of unresolved scientific and technical struggles, some of which still puzzle researchers in the field and are presented in this chapter.

A review of fibrin and fibrin composites for bone tissue engineering

PubMed Central

Noori, Alireza; Ashrafi, Seyed Jamal; Vaez-Ghaemi, Roza; Hatamian-Zaremi, Ashraf; Webster, Thomas J

2017-01-01

Tissue engineering has emerged as a new treatment approach for bone repair and regeneration seeking to address limitations associated with current therapies, such as autologous bone grafting. While many bone tissue engineering approaches have traditionally focused on synthetic materials (such as polymers or hydrogels), there has been a lot of excitement surrounding the use of natural materials due to their biologically inspired properties. Fibrin is a natural scaffold formed following tissue injury that initiates hemostasis and provides the initial matrix useful for cell adhesion, migration, proliferation, and differentiation. Fibrin has captured the interest of bone tissue engineers due to its excellent biocompatibility, controllable biodegradability, and ability to deliver cells and biomolecules. Fibrin is particularly appealing because its precursors, fibrinogen, and thrombin, which can be derived from the patient’s own blood, enable the fabrication of completely autologous scaffolds. In this article, we highlight the unique properties of fibrin as a scaffolding material to treat bone defects. Moreover, we emphasize its role in bone tissue engineering nanocomposites where approaches further emulate the natural nanostructured features of bone when using fibrin and other nanomaterials. We also review the preparation methods of fibrin glue and then discuss a wide range of fibrin applications in bone tissue engineering. These include the delivery of cells and/or biomolecules to a defect site, distributing cells, and/or growth factors throughout other pre-formed scaffolds and enhancing the physical as well as biological properties of other biomaterials. Thoughts on the future direction of fibrin research for bone tissue engineering are also presented. In the future, the development of fibrin precursors as recombinant proteins will solve problems associated with using multiple or single-donor fibrin glue, and the combination of nanomaterials that allow for the incorporation of biomolecules with fibrin will significantly improve the efficacy of fibrin for numerous bone tissue engineering applications. PMID:28761338

A review of fibrin and fibrin composites for bone tissue engineering.

PubMed

Noori, Alireza; Ashrafi, Seyed Jamal; Vaez-Ghaemi, Roza; Hatamian-Zaremi, Ashraf; Webster, Thomas J

2017-01-01

Tissue engineering has emerged as a new treatment approach for bone repair and regeneration seeking to address limitations associated with current therapies, such as autologous bone grafting. While many bone tissue engineering approaches have traditionally focused on synthetic materials (such as polymers or hydrogels), there has been a lot of excitement surrounding the use of natural materials due to their biologically inspired properties. Fibrin is a natural scaffold formed following tissue injury that initiates hemostasis and provides the initial matrix useful for cell adhesion, migration, proliferation, and differentiation. Fibrin has captured the interest of bone tissue engineers due to its excellent biocompatibility, controllable biodegradability, and ability to deliver cells and biomolecules. Fibrin is particularly appealing because its precursors, fibrinogen, and thrombin, which can be derived from the patient's own blood, enable the fabrication of completely autologous scaffolds. In this article, we highlight the unique properties of fibrin as a scaffolding material to treat bone defects. Moreover, we emphasize its role in bone tissue engineering nanocomposites where approaches further emulate the natural nanostructured features of bone when using fibrin and other nanomaterials. We also review the preparation methods of fibrin glue and then discuss a wide range of fibrin applications in bone tissue engineering. These include the delivery of cells and/or biomolecules to a defect site, distributing cells, and/or growth factors throughout other pre-formed scaffolds and enhancing the physical as well as biological properties of other biomaterials. Thoughts on the future direction of fibrin research for bone tissue engineering are also presented. In the future, the development of fibrin precursors as recombinant proteins will solve problems associated with using multiple or single-donor fibrin glue, and the combination of nanomaterials that allow for the incorporation of biomolecules with fibrin will significantly improve the efficacy of fibrin for numerous bone tissue engineering applications.

Recent Advances in Laser-Ablative Synthesis of Bare Au and Si Nanoparticles and Assessment of Their Prospects for Tissue Engineering Applications.

PubMed

Al-Kattan, Ahmed; Nirwan, Viraj P; Popov, Anton; Ryabchikov, Yury V; Tselikov, Gleb; Sentis, Marc; Fahmi, Amir; Kabashin, Andrei V

2018-05-24

Driven by surface cleanness and unique physical, optical and chemical properties, bare (ligand-free) laser-synthesized nanoparticles (NPs) are now in the focus of interest as promising materials for the development of advanced biomedical platforms related to biosensing, bioimaging and therapeutic drug delivery. We recently achieved significant progress in the synthesis of bare gold (Au) and silicon (Si) NPs and their testing in biomedical tasks, including cancer imaging and therapy, biofuel cells, etc. We also showed that these nanomaterials can be excellent candidates for tissue engineering applications. This review is aimed at the description of our recent progress in laser synthesis of bare Si and Au NPs and their testing as functional modules (additives) in innovative scaffold platforms intended for tissue engineering tasks.

[Micro/nano-engineering to control growth of neuronal cells and tissue engineering applied to the central nervous system].

PubMed

Béduer, Amélie; Vaysse, Laurence; Loubinoux, Isabelle; Vieu, Christophe

2013-01-01

Central nervous system pathologies are often characterized by the loss of cell populations. A promising therapy now being developed consists in using bioactive materials, associating grafted cells to biopolymers which provide a scaffold for the in vitro building of new tissues, to be implanted in vivo. In the present article, the state of the art of this field, at crossroads between microtechnology and neuroscience, is described in detail; thereafter our own approach and results about interactions between adult human neural stem cells and microstructured polymers are summarized and discussed. In a second part, some central nervous system repair strategies, based on cerebral tissue engineering, are presented. We will report the main results of our studies to work out and characterize in vivo a cerebral bioprosthesis. © Société de Biologie, 2014.

Tissue engineering strategies in spinal arthrodesis: the clinical imperative and challenges to clinical translation.

PubMed

Evans, Nick R; Davies, Evan M; Dare, Chris J; Oreffo, Richard Oc

2013-01-01

Skeletal disorders requiring the regeneration or de novo production of bone present considerable reconstructive challenges and are one of the main driving forces for the development of skeletal tissue engineering strategies. The skeletal or mesenchymal stem cell is a fundamental requirement for osteogenesis and plays a pivotal role in the design and application of these strategies. Research activity has focused on incorporating the biological role of the mesenchymal stem cell with the developing fields of material science and gene therapy in order to create a construct that is not only capable of inducing host osteoblasts to produce bone, but is also osteogenic in its own right. This review explores the clinical need for reparative approaches in spinal arthrodesis, identifying recent tissue engineering strategies employed to promote spinal fusion, and considers the ongoing challenges to successful clinical translation.

Gene therapy and tissue engineering based on muscle-derived stem cells.

PubMed

Deasy, Bridget M; Huard, Johnny

2002-08-01

Skeletal muscle represents a convenient source of stem cells for cell-based tissue and genetic engineering. Muscle-derived stem cells (MDSCs) exhibit both multipotentiality and self-renewal capabilities, and are considered to be distinct from the well-studied satellite cell, another type of muscle stem cell that is capable of self-renewal and myogenic lineage differentiation. The MDSC appears to have less restricted differentiation capabilities as compared with the satellite cell, and may be a precursor of the satellite cell. This review considers the evidence for the existence of MDSCs as well as their origin. We will discuss recent investigations highlighting the potential of stem cell transplantation for the treatment of skeletal, cardiac and smooth muscle injuries and disease. We will highlight challenges in bridging the gap between understanding basic stem cell biology and clinical utilization for cell therapy.

Gene Therapy of Bone Morphogenetic Protein for Periodontal Tissue Engineering

PubMed Central

Jin, Q-M.; Anusaksathien, O.; Webb, S.A.; Rutherford, R.B.; Giannobile, W.V.

2009-01-01

Background The reconstruction of lost periodontal support including bone, ligament, and cementum is a major goal of therapy. Bone morphogenetic proteins (BMPs) have shown much potential in the regeneration of the periodontium. Limitations of BMP administration to periodontal lesions include need for high-dose bolus delivery, BMP transient biological activity, and low bioavailability of factors at the wound site. Gene transfer offers promise as an alternative treatment strategy to deliver BMPs to periodontal tissues. Methods This study utilized ex vivo BMP-7 gene transfer to stimulate tissue engineering of alveolar bone wounds. Syngeneic dermal fibroblasts (SDFs) were transduced ex vivo with adenoviruses encoding either green fluorescent protein (Ad-GFP or control virus), BMP-7 (Ad-BMP-7), or an antagonist of BMP bioactivity, noggin (Ad-noggin). Transduced cells were seeded onto gelatin carriers and then transplanted to large mandibular alveolar bone defects in a rat wound repair model. Results Ad-noggin treatment tended to inhibit osteogenesis as compared to the control-treated and Ad-BMP-7-treated specimens. The osseous lesions treated by Ad-BMP-7 gene delivery demonstrated rapid chrondrogenesis, with subsequent osteogenesis, cementogenesis and predictable bridging of the periodontal bone defects. Conclusion These results demonstrate the first successful evidence of periodontal tissue engineering using ex vivo gene transfer of BMPs and offers a new approach for repairing periodontal defects. PMID:12666709

The Survey on Cellular and Engineered Tissue Therapies in Europe in 2012*

PubMed Central

Ireland, Hilary; Baldomero, Helen; Passweg, Jakob

2015-01-01

Following the coordinated efforts of five established scientific organizations, this report describes activity in Europe for the year 2012 in the area of cellular and engineered tissue therapies, excluding hematopoietic stem cell (HSC) treatments for the reconstitution of hematopoiesis. Three hundred thirteen teams from 33 countries responded to the cellular and engineered tissue therapy survey: 138 teams from 27 countries provided data on 2157 patients, while a further 175 teams reported no activity. Indications were musculoskeletal/rheumatological disorders (36%; 80% autologous), cardiovascular disorders (25%; 95% autologous), hematology/oncology, predominantly prevention or treatment of graft versus host disease and HSC graft enhancement (19%; 1% autologous), neurological disorders (3%; 99% autologous), gastrointestinal disorders (1%; 71% autologous), and other indications (16%; 79% autologous). Autologous cells were predominantly used for musculoskeletal/rheumatological (42%) and cardiovascular (34%) disorders, whereas allogeneic cells were mainly used for hematology/oncology (60%). The reported cell types were mesenchymal stem/stromal cells (49%), HSC (28%), chondrocytes (11%), dermal fibroblasts (4%), keratinocytes (1%), and others (7%). In 51% of the grafts, cells were delivered after ex vivo expansion, whereas cells were transduced or sorted in 10% and 16%, respectively, of the reported cases. Cells were delivered intra-organ (35%), intravenously (31%), on a membrane or gel (15%), or using 3D scaffolds (19%). The data are compared with those collected since 2008 to identify trends in the field and discussed in the light of recent publications and ongoing clinical studies. PMID:25425342

Carbon nanotube scaffolds as emerging nanoplatform for myocardial tissue regeneration: A review of recent developments and therapeutic implications.

PubMed

Gorain, Bapi; Choudhury, Hira; Pandey, Manisha; Kesharwani, Prashant; Abeer, Muhammad Mustafa; Tekade, Rakesh Kumar; Hussain, Zahid

2018-08-01

Myocardial infarction (cardiac tissue death) is among the most prevalent causes of death among the cardiac patients due to the inability of self-repair in cardiac tissues. Myocardial tissue engineering is regarded as one of the most realistic strategies for repairing damaged cardiac tissue. However, hindrance in transduction of electric signals across the cardiomyocytes due to insulating properties of polymeric materials worsens the clinical viability of myocardial tissue engineering. Aligned and conductive scaffolds based on Carbon nanotubes (CNT) have gained remarkable recognition due to their exceptional attributes which provide synthetic but viable microenvironment for regeneration of engineered cardiomyocytes. This review presents an overview and critical analysis of pharmaceutical implications and therapeutic feasibility of CNT based scaffolds in improving the cardiac tissue regeneration and functionality. The expository analysis of the available evidence revealed that inclusion of single- or multi-walled CNT into fibrous, polymeric, and elastomeric scaffolds results in significant improvement in electrical stimulation and signal transduction through cardiomyocytes. Moreover, incorporation of CNT in engineering scaffolds showed a greater potential of augmenting cardiomyocyte proliferation, differentiation, and maturation and has improved synchronous beating of cardiomyocytes. Despite promising ability of CNT in promoting functionality of cardiomyocytes, their presence in scaffolds resulted in substantial improvement in mechanical properties and structural integrity. Conclusively, this review provides new insight into the remarkable potential of CNT aligned scaffolds in improving the functionality of engineered cardiac tissue and signifies their feasibility in cardiac tissue regenerative medicines and stem cell therapy. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Stem Cell-based Tissue Engineering Approaches for Musculoskeletal Regeneration

PubMed Central

Brown, Patrick T.; Handorf, Andrew M.; Jeon, Won Bae; Li, Wan-Ju

2014-01-01

The field of regenerative medicine and tissue engineering is an ever evolving field that holds promise in treating numerous musculoskeletal diseases and injuries. An important impetus in the development of the field was the discovery and implementation of stem cells. The utilization of mesenchymal stem cells, and later embryonic and induced pluripotent stem cells, opens new arenas for tissue engineering and presents the potential of developing stem cell-based therapies for disease treatment. Multipotent and pluripotent stem cells can produce various lineage tissues, and allow for derivation of a tissue that may be comprised of multiple cell types. As the field grows, the combination of biomaterial scaffolds and bioreactors provides methods to create an environment for stem cells that better represent their microenvironment for new tissue formation. As technologies for the fabrication of biomaterial scaffolds advance, the ability of scaffolds to modulate stem cell behavior advances as well. The composition of scaffolds could be of natural or synthetic materials and could be tailored to enhance cell self-renewal and/or direct cell fates. In addition to biomaterial scaffolds, studies of tissue development and cellular microenvironments have determined other factors, such as growth factors and oxygen tension, that are crucial to the regulation of stem cell activity. The overarching goal of stem cell-based tissue engineering research is to precisely control differentiation of stem cells in culture. In this article, we review current developments in tissue engineering, focusing on several stem cell sources, induction factors including growth factors, oxygen tension, biomaterials, and mechanical stimulation, and the internal and external regulatory mechanisms that govern proliferation and differentiation. PMID:23432679

Strategic Design and Fabrication of Engineered Scaffolds for Articular Cartilage Repair

PubMed Central

Izadifar, Zohreh; Chen, Xiongbiao; Kulyk, William

2012-01-01

Damage to articular cartilage can eventually lead to osteoarthritis (OA), a debilitating, degenerative joint disease that affects millions of people around the world. The limited natural healing ability of cartilage and the limitations of currently available therapies make treatment of cartilage defects a challenging clinical issue. Hopes have been raised for the repair of articular cartilage with the help of supportive structures, called scaffolds, created through tissue engineering (TE). Over the past two decades, different designs and fabrication techniques have been investigated for developing TE scaffolds suitable for the construction of transplantable artificial cartilage tissue substitutes. Advances in fabrication technologies now enable the strategic design of scaffolds with complex, biomimetic structures and properties. In particular, scaffolds with hybrid and/or biomimetic zonal designs have recently been developed for cartilage tissue engineering applications. This paper reviews critical aspects of the design of engineered scaffolds for articular cartilage repair as well as the available advanced fabrication techniques. In addition, recent studies on the design of hybrid and zonal scaffolds for use in cartilage tissue repair are highlighted. PMID:24955748

Bone regenerative medicine: classic options, novel strategies, and future directions

PubMed Central

2014-01-01

This review analyzes the literature of bone grafts and introduces tissue engineering as a strategy in this field of orthopedic surgery. We evaluated articles concerning bone grafts; analyzed characteristics, advantages, and limitations of the grafts; and provided explanations about bone-tissue engineering technologies. Many bone grafting materials are available to enhance bone healing and regeneration, from bone autografts to graft substitutes; they can be used alone or in combination. Autografts are the gold standard for this purpose, since they provide osteogenic cells, osteoinductive growth factors, and an osteoconductive scaffold, all essential for new bone growth. Autografts carry the limitations of morbidity at the harvesting site and limited availability. Allografts and xenografts carry the risk of disease transmission and rejection. Tissue engineering is a new and developing option that had been introduced to reduce limitations of bone grafts and improve the healing processes of the bone fractures and defects. The combined use of scaffolds, healing promoting factors, together with gene therapy, and, more recently, three-dimensional printing of tissue-engineered constructs may open new insights in the near future. PMID:24628910

Development of Poly(Ethylene Glycol) Hydrogels for Salivary Gland Tissue Engineering Applications

PubMed Central

Shubin, Andrew D.; Felong, Timothy J.; Graunke, Dean; Ovitt, Catherine E.

2015-01-01

More than 40,000 patients are diagnosed with head and neck cancers annually in the United States with the vast majority receiving radiation therapy. Salivary glands are irreparably damaged by radiation therapy resulting in xerostomia, which severely affects patient quality of life. Cell-based therapies have shown some promise in mouse models of radiation-induced xerostomia, but they suffer from insufficient and inconsistent gland regeneration and accompanying secretory function. To aid in the development of regenerative therapies, poly(ethylene glycol) hydrogels were investigated for the encapsulation of primary submandibular gland (SMG) cells for tissue engineering applications. Different methods of hydrogel formation and cell preparation were examined to identify cytocompatible encapsulation conditions for SMG cells. Cell viability was much higher after thiol-ene polymerizations compared with conventional methacrylate polymerizations due to reduced membrane peroxidation and intracellular reactive oxygen species formation. In addition, the formation of multicellular microspheres before encapsulation maximized cell–cell contacts and increased viability of SMG cells over 14-day culture periods. Thiol-ene hydrogel-encapsulated microspheres also promoted SMG proliferation. Lineage tracing was employed to determine the cellular composition of hydrogel-encapsulated microspheres using markers for acinar (Mist1) and duct (Keratin5) cells. Our findings indicate that both acinar and duct cell phenotypes are present throughout the 14 day culture period. However, the acinar:duct cell ratios are reduced over time, likely due to duct cell proliferation. Altogether, permissive encapsulation methods for primary SMG cells have been identified that promote cell viability, proliferation, and maintenance of differentiated salivary gland cell phenotypes, which allows for translation of this approach for salivary gland tissue engineering applications. PMID:25762214

Gene therapy strategies for urological dysfunction.

PubMed

Chancellor, M B; Yoshimura, N; Pruchnic, R; Huard, J

2001-07-01

Novel molecular techniques such as conventional and ex vivo gene therapy, and tissue engineering have only recently been introduced to the field of urology. The lower urinary tract is ideally suited for minimally invasive therapy, and also ex vivo approaches would limit the risk of systemic side effects. Muscle-derived stem cells have been used successfully to treat stress incontinence, and rats with diabetic bladder dysfunction benefited from nerve growth factor (NGF)-based gene therapy. Nitric oxide synthase and capase-7 might provide suitable gene therapy targets for erectile dysfunction and benign prostatic hyperplasia, respectively.

Salivary enhancement: current status and future therapies.

PubMed

Atkinson, J C; Baum, B J

2001-10-01

Saliva provides the principal protective milieu for teeth by modulating oral microbial ecosystems and reversing the initial phases of caries development. Patients with inadequate salivary function are at increased risk for dental decay. Therefore, it is likely that therapies that increase overall fluid output of these individuals will reverse early carious lesions. The most common causes of salivary dysfunction are medication usage, Sjögren's syndrome, and damage of salivary parenchyma during therapeutic irradiation. For patients with remaining functional acinar tissue, treatment with the parasypathomimetic secretogogues pilocarpine and Cevimeline may provide relief. However, these medications do not benefit all patients. The possibilities of using gene therapy and tissue engineering to develop treatments for those with severe salivary dysfunction are discussed.

Biological augmentation and tissue engineering approaches in meniscus surgery.

PubMed

Moran, Cathal J; Busilacchi, Alberto; Lee, Cassandra A; Athanasiou, Kyriacos A; Verdonk, Peter C

2015-05-01

The purpose of this review was to evaluate the role of biological augmentation and tissue engineering strategies in meniscus surgery. Although clinical (human), preclinical (animal), and in vitro tissue engineering studies are included here, we have placed additional focus on addressing preclinical and clinical studies reported during the 5-year period used in this review in a systematic fashion while also providing a summary review of some important in vitro tissue engineering findings in the field over the past decade. A search was performed on PubMed for original works published from 2009 to March 31, 2014 using the term "meniscus" with all the following terms: "scaffolds," "constructs," "cells," "growth factors," "implant," "tissue engineering," and "regenerative medicine." Inclusion criteria were the following: English-language articles and original clinical, preclinical (in vivo), and in vitro studies of tissue engineering and regenerative medicine application in knee meniscus lesions published from 2009 to March 31, 2014. Three clinical studies and 18 preclinical studies were identified along with 68 tissue engineering in vitro studies. These reports show the increasing promise of biological augmentation and tissue engineering strategies in meniscus surgery. The role of stem cell and growth factor therapy appears to be particularly useful. A review of in vitro tissue engineering studies found a large number of scaffold types to be of promise for meniscus replacement. Limitations include a relatively low number of clinical or preclinical in vivo studies, in addition to the fact there is as yet no report in the literature of a tissue-engineered meniscus construct used clinically. Neither does the literature provide clarity on the optimal meniscus scaffold type or biological augmentation with which meniscus repair or replacement would be best addressed in the future. There is increasing focus on the role of mechanobiology and biomechanical and biochemical cues in this process, however, and it is hoped that this may lead to improvements in this strategy. There appears to be significant potential for biological augmentation and tissue engineering strategies in meniscus surgery to enhance options for repair and replacement. However, there are still relatively few clinical studies being reported in this regard. There is a strong need for improved translational activities and infrastructure to link the large amounts of in vitro and preclinical biological and tissue engineering data to clinical application. Level IV, systematic review of Level I-IV studies. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Engineered matrices for bone regeneration

NASA Astrophysics Data System (ADS)

Winn, Shelley R.; Hu, Yunhua; Pugh, Amy; Brown, Leanna; Nguyen, Jesse T.; Hollinger, Jeffrey O.

2000-06-01

Traditional therapies of autografts and allogeneic banked bone can promote reasonable clinical outcome to repair damaged bone. However, under certain conditions the success of these traditional approaches plummets, providing the incentive for researchers to develop clinical alternatives. The evolving field of tissue engineering in the musculoskeletal system attempts to mimic many of the components from the intact, healthy subject. Those components consist of a biologic scaffold, cells, extracellular matrix, and signaling molecules. The bone biomimetic, i.e., an engineered matrix, provides a porous structural architecture for the regeneration and ingrowth of osseous tissue at the site of injury. To further enhance the regenerative cascade, our strategy has involved porous biodegradable scaffolds containing and releasing signaling molecules and providing a suitable environment for cell attachment, growth and differentiation. In addition, the inclusion of genetically modified osteogenic precursor cells has brought the technology closer to developing a tissue-engineered equivalent. The presentation will describe various formulations and the methods utilized to evaluate the clinical utility of these biomimetics.

Topographical Control of Ocular Cell Types for Tissue Engineering

PubMed Central

McHugh, Kevin J.; Saint-Geniez, Magali; Tao, Sarah L.

2014-01-01

Visual impairment affects over 285 million people worldwide and has a major impact on an individual’s quality of life. Tissue engineering has the potential to increase quality of life for many of these patients by preventing vision loss or restoring vision using cell-based therapies. However, these strategies will require an understanding of the microenvironmental factors that influence cell behavior. The eye is a well-organized organ whose structural complexity is essential for proper function. Interactions between ocular cells and their highly ordered extracellular matrix are necessary for maintaining key tissue properties including corneal transparency and retinal lamination. Therefore, it is not surprising that culturing these cells in vitro on traditional flat substrates result in irregular morphology. Instead, topographically patterned biomaterials better mimic native extracellular matrix and have been shown to elicit in vivo-like morphology and gene expression which is essential for tissue engineering. Herein we review multiple methods for producing well-controlled topography and discuss optimal biomaterial scaffold design for cells of the cornea, retina, and lens. PMID:23744715

Amniotic Fluid-Derived Stem Cells for Cardiovascular Tissue Engineering Applications

PubMed Central

Petsche Connell, Jennifer; Camci-Unal, Gulden; Khademhosseini, Ali

2013-01-01

Recent research has demonstrated that a population of stem cells can be isolated from amniotic fluid removed by amniocentesis that are broadly multipotent and nontumorogenic. These amniotic fluid-derived stem cells (AFSC) could potentially provide an autologous cell source for treatment of congenital defects identified during gestation, particularly cardiovascular defects. In this review, the various methods of isolating, sorting, and culturing AFSC are compared, along with techniques for inducing differentiation into cardiac myocytes and endothelial cells. Although research has not demonstrated complete and high-yield cardiac differentiation, AFSC have been shown to effectively differentiate into endothelial cells and can effectively support cardiac tissue. Additionally, several tissue engineering and regenerative therapeutic approaches for the use of these cells in heart patches, injection after myocardial infarction, heart valves, vascularized scaffolds, and blood vessels are summarized. These applications show great promise in the treatment of congenital cardiovascular defects, and further studies of isolation, culture, and differentiation of AFSC will help to develop their use for tissue engineering, regenerative medicine, and cardiovascular therapies. PMID:23350771

TOPICAL REVIEW: Stem cells engineering for cell-based therapy

NASA Astrophysics Data System (ADS)

Taupin, Philippe

2007-09-01

Stem cells carry the promise to cure a broad range of diseases and injuries, from diabetes, heart and muscular diseases, to neurological diseases, disorders and injuries. Significant progresses have been made in stem cell research over the past decade; the derivation of embryonic stem cells (ESCs) from human tissues, the development of cloning technology by somatic cell nuclear transfer (SCNT) and the confirmation that neurogenesis occurs in the adult mammalian brain and that neural stem cells (NSCs) reside in the adult central nervous system (CNS), including that of humans. Despite these advances, there may be decades before stem cell research will translate into therapy. Stem cell research is also subject to ethical and political debates, controversies and legislation, which slow its progress. Cell engineering has proven successful in bringing genetic research to therapy. In this review, I will review, in two examples, how investigators are applying cell engineering to stem cell biology to circumvent stem cells' ethical and political constraints and bolster stem cell research and therapy.

The effects of dynamic loading on the intervertebral disc.

PubMed

Chan, Samantha C W; Ferguson, Stephen J; Gantenbein-Ritter, Benjamin

2011-11-01

Loading is important to maintain the balance of matrix turnover in the intervertebral disc (IVD). Daily cyclic diurnal assists in the transport of large soluble factors across the IVD and its surrounding circulation and applies direct and indirect stimulus to disc cells. Acute mechanical injury and accumulated overloading, however, could induce disc degeneration. Recently, there is more information available on how cyclic loading, especially axial compression and hydrostatic pressure, affects IVD cell biology. This review summarises recent studies on the response of the IVD and stem cells to applied cyclic compression and hydrostatic pressure. These studies investigate the possible role of loading in the initiation and progression of disc degeneration as well as quantifying a physiological loading condition for the study of disc degeneration biological therapy. Subsequently, a possible physiological/beneficial loading range is proposed. This physiological/beneficial loading could provide insight into how to design loading regimes in specific system for the testing of various biological therapies such as cell therapy, chemical therapy or tissue engineering constructs to achieve a better final outcome. In addition, the parameter space of 'physiological' loading may also be an important factor for the differentiation of stem cells towards most ideally 'discogenic' cells for tissue engineering purpose.

Engineered Biomaterials to Enhance Stem Cell-Based Cardiac Tissue Engineering and Therapy.

PubMed

Hasan, Anwarul; Waters, Renae; Roula, Boustany; Dana, Rahbani; Yara, Seif; Alexandre, Toubia; Paul, Arghya

2016-07-01

Cardiovascular disease is a leading cause of death worldwide. Since adult cardiac cells are limited in their proliferation, cardiac tissue with dead or damaged cardiac cells downstream of the occluded vessel does not regenerate after myocardial infarction. The cardiac tissue is then replaced with nonfunctional fibrotic scar tissue rather than new cardiac cells, which leaves the heart weak. The limited proliferation ability of host cardiac cells has motivated investigators to research the potential cardiac regenerative ability of stem cells. Considerable progress has been made in this endeavor. However, the optimum type of stem cells along with the most suitable matrix-material and cellular microenvironmental cues are yet to be identified or agreed upon. This review presents an overview of various types of biofunctional materials and biomaterial matrices, which in combination with stem cells, have shown promises for cardiac tissue replacement and reinforcement. Engineered biomaterials also have applications in cardiac tissue engineering, in which tissue constructs are developed in vitro by combining stem cells and biomaterial scaffolds for drug screening or eventual implantation. This review highlights the benefits of using biomaterials in conjunction with stem cells to repair damaged myocardium and give a brief description of the properties of these biomaterials that make them such valuable tools to the field. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Regenerative endodontics and tissue engineering: what the future holds?

PubMed

Goodis, Harold E; Kinaia, Bassam Michael; Kinaia, Atheel M; Chogle, Sami M A

2012-07-01

The work performed by researchers in regenerative endodontics and tissue engineering over the last decades has been superb; however, many questions remain to be answered. The basic biologic mechanisms must be elucidated that will allow the development of dental pulp and dentin in situ. Stress must be placed on the many questions that will lead to the design of effective, safe treatment options and therapies. This article discusses those questions, the answers to which may become the future of regenerative endodontics. The future remains bright, but proper support and patience are required. Copyright © 2012 Elsevier Inc. All rights reserved.

Nanotechnology for the detection and therapy of stroke.

PubMed

Kyle, Stuart; Saha, Sikha

2014-11-01

Over the years, nanotechnology has greatly developed, moving from careful design strategies and synthesis of novel nanostructures to producing them for specific medical and biological applications. The use of nanotechnology in diagnostics, drug delivery, and tissue engineering holds great promise for the treatment of stroke in the future. Nanoparticles are employed to monitor grafted cells upon implantation, or to enhance the imagery of the tissue, which is coupled with a noninvasive imaging modality such as magnetic resonance imaging, computed axial tomography or positron emission tomography scan. Contrast imaging agents used can range from iron oxide, perfluorocarbon, cerium oxide or platinum nanoparticles to quantum dots. The use of nanomaterial scaffolds for neuroregeneration is another area of nanomedicine, which involves the creation of an extracellular matrix mimic that not only serves as a structural support but promotes neuronal growth, inhibits glial differentiation, and controls hemostasis. Promisingly, carbon nanotubes can act as scaffolds for stem cell therapy and functionalizing these scaffolds may enhance their therapeutic potential for treatment of stroke. This Progress Report highlights the recent developments in nanotechnology for the detection and therapy of stroke. Recent advances in the use of nanomaterials as tissue engineering scaffolds for neuroregeneration will also be discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Developmental engineering: a new paradigm for the design and manufacturing of cell-based products. Part I: from three-dimensional cell growth to biomimetics of in vivo development.

PubMed

Lenas, Petros; Moos, Malcolm; Luyten, Frank P

2009-12-01

Recent advances in developmental biology, systems biology, and network science are converging to poise the heretofore largely empirical field of tissue engineering on the brink of a metamorphosis into a rigorous discipline based on universally accepted engineering principles of quality by design. Failure of more simplistic approaches to the manufacture of cell-based therapies has led to increasing appreciation of the need to imitate, at least to some degree, natural mechanisms that control cell fate and differentiation. The identification of many of these mechanisms, which in general are based on cell signaling pathways, is an important step in this direction. Some well-accepted empirical concepts of developmental biology, such as path-dependence, robustness, modularity, and semiautonomy of intermediate tissue forms, that appear sequentially during tissue development are starting to be incorporated in process design.

Regenerative endodontics: a state of the art.

PubMed

Bansal, Rashmi; Bansal, Rajesh

2011-01-01

Scientific advances in the creation of restorative biomaterials, in vitro cell culture technology, tissue grafting, tissue engineering, molecular biology and the human genome project provide the basis for the introduction of new technologies into dentistry. Non-vital infected teeth have long been treated with root canal therapy (for mature root apex) and apexification (for immature root apex), or doomed to extraction. Although successful, current treatments fail to re-establish healthy pulp tissue in these teeth. But, what if the non-vital tooth could be made vital once again? That is the hope offered by regenerative endodontics, an emerging field focused on replacing traumatized and diseased pulp with functional pulp tissue. Restoration of vitality of non-vital tooth is based on tissue engineering and revascularization procedures. The purpose of this article is to review these biological procedures and the hurdles that must be overcome to develop regenerative endodontic procedures.

Recent tissue engineering-based advances for effective rAAV-mediated gene transfer in the musculoskeletal system.

PubMed

Rey-Rico, Ana; Cucchiarini, Magali

2016-04-01

Musculoskeletal tissues are diverse and significantly different in their ability to repair upon injury. Current treatments often fail to reproduce the natural functions of the native tissue, leading to an imperfect healing. Gene therapy might improve the repair of tissues by providing a temporarily and spatially defined expression of the therapeutic gene(s) at the site of the injury. Several gene transfer vehicles have been developed to modify various human cells and tissues from musculoskeletal system among which the non-pathogenic, effective, and relatively safe recombinant adeno-associated viral (rAAV) vectors that have emerged as the preferred gene delivery system to treat human disorders. Adapting tissue engineering platforms to gene transfer approaches mediated by rAAV vectors is an attractive tool to circumvent both the limitations of the current therapeutic options to promote an effective healing of the tissue and the natural obstacles from these clinically adapted vectors to achieve an efficient and durable gene expression of the therapeutic sequences within the lesions.

Pulp regeneration concepts for non-vital teeth: from tissue engineering to clinical approaches.

PubMed

Orti, Valérie; Collart-Dutilleul, Pierre-Yves; Piglionico, Sofía Silvia; Pall, Orsolya; Cuisinier, Frédéric; Panayotov, Ivan Vladislavov

2018-05-04

Following the basis of tissue engineering (Cells - Scaffold - Bioactive molecules), regenerative endodontic has emerged as a new concept of dental treatment. Clinical procedures have been proposed by endodontic practitioners willing to promote regenerative therapy. Preserving pulp vitality was a first approach. Later procedures aimed to regenerate a vascularized pulp in necrotic root canals. However, there is still no protocol allowing an effective regeneration of necrotic pulp tissue either in immature or mature teeth. This review explore in vitro and preclinical concepts developed during the last decade, especially the potential use of stem cells, bioactive molecules and scaffolds, and makes a comparison with the goals achieved so far in clinical practice. Regeneration of pulp-like tissue has been shown in various experimental conditions. However, the appropriate techniques are currently in a developmental stage. The ideal combination of scaffolds and growth factors to obtain a complete regeneration of the pulp-dentin complex is still unknown. The use of stem cells, especially from pulp origin, sounds promising for pulp regeneration therapy, but it has not been applied so far for clinical endodontics, in case of necrotic teeth. The gap observed between the hope raised from in vitro experiments and the reality of endodontic treatments suggests that clinical success may be achieved without external stem cell application. Therefore, procedures using the concept of cell homing, through evoked bleeding, that permit to recreate a living tissue that mimics the original pulp have been proposed. Perspectives for pulp tissue engineering in a near future include a better control of clinical parameters and pragmatic approach of the experimental results (autologous stem cells from cell homing, controlled release of growth factors). In the coming years, this therapeutic strategy will probably become a clinical reality, even for mature necrotic teeth.

[Nanotechnology future of medicine].

PubMed

Terlega, Katarzyna; Latocha, Małgorzata

2012-10-01

Nanotechnology enables to produce products with new, exactly specified, unique properties. Those products are finding application in various branches of electronic, chemical, food and textile industry as well as in medicine, pharmacy, agriculture, architectural engineering, aviation and in defense. In this paper structures used in nanomedicine were characterized. Possibilities and first effort of application of nanotechnology in diagnostics and therapy were also described. Nanotechnology provides tools which allow to identifying changes and taking repair operations on cellular and molecular level and applying therapy oriented for specific structures in cell. Great hope are being associated with entering nanotechnology into the regenerative medicine. It requires astute recognition bases of tissue regeneration biology--initiating signals as well as the intricate control system of the progress of this process. However application of nanotechnology in tissue engineering allows to avoiding problems associated with loss properties of implants what is frequent cause of performing another surgical procedure at present.

Scaffold-based Anti-infection Strategies in Bone Repair

PubMed Central

Johnson, Christopher T.; García, Andrés J.

2014-01-01

Bone fractures and non-union defects often require surgical intervention where biomaterials are used to correct the defect, and approximately 10% of these procedures are compromised by bacterial infection. Currently, treatment options are limited to sustained, high doses of antibiotics and surgical debridement of affected tissue, leaving a significant, unmet need for the development of therapies to combat device-associated biofilm and infections. Engineering implants to prevent infection is a desirable material characteristic. Tissue engineered scaffolds for bone repair provide a means to both regenerate bone and serve as a base for adding antimicrobial agents. Incorporating anti-infection properties into regenerative medicine therapies could improve clinical outcomes and reduce the morbidity and mortality associated with biomaterial implant-associated infections. This review focuses on current animal models and technologies available to assess bone repair in the context of infection, antimicrobial agents to fight infection, the current state of antimicrobial scaffolds, and future directions in the field. PMID:25476163

Engineering biosynthetic excitable tissues from unexcitable cells for electrophysiological and cell therapy studies.

PubMed

Kirkton, Robert D; Bursac, Nenad

2011-01-01

Patch-clamp recordings in single-cell expression systems have been traditionally used to study the function of ion channels. However, this experimental setting does not enable assessment of tissue-level function such as action potential (AP) conduction. Here we introduce a biosynthetic system that permits studies of both channel activity in single cells and electrical conduction in multicellular networks. We convert unexcitable somatic cells into an autonomous source of electrically excitable and conducting cells by stably expressing only three membrane channels. The specific roles that these expressed channels have on AP shape and conduction are revealed by different pharmacological and pacing protocols. Furthermore, we demonstrate that biosynthetic excitable cells and tissues can repair large conduction defects within primary 2- and 3-dimensional cardiac cell cultures. This approach enables novel studies of ion channel function in a reproducible tissue-level setting and may stimulate the development of new cell-based therapies for excitable tissue repair.

Clinical implications of basic science discoveries: induced pluripotent stem cell therapy in transplantation--a potential role for immunologic tolerance.

PubMed

Wertheim, J A; Leventhal, J R

2015-04-01

Induced pluripotent stem cells (iPSCs) hold the potential for future development of genetically identical tissues from almost any mature cell lineage. For clinical applications in cell therapy and transplantation, it may provide a means to one-day restore dysfunctional or damaged tissue without the need for immunosuppression. A recent study by de Almeida et al published in the journal Nature Communications indicates that iPSCs may indeed elicit an immune response that evolves as cells differentiate toward maturity to induce a state of tolerance within a recipient animal. If these early findings hold true, it suggests a possible explanation for self-recognition of mature cells derived from iPSCs for use in future therapeutic interventions in transplantation such as cellular therapy or tissue engineering. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

Stromal cells in tissue homeostasis: balancing regeneration and fibrosis.

PubMed

Rabelink, Ton J; Little, Melissa H

2013-12-01

The ageing population and the increasing prevalence of noncommunicable diseases such as diabetes and hypertension have led to an increased prevalence of chronic kidney disease. The generation of de novo kidney tissue from embryonic tissue and stem cells using tissue engineering approaches is being explored as an alternative to renal replacement therapy for treating the disease. It is, however, becoming clear that resident cells can not only induce fibrotic repair, but can also restore damaged kidney tissue. Mobilizing this innate capacity of the kidney to regenerate is of particular interest in the prevention of irreversible kidney failure. A novel concept is that the interaction of interstitial stromal cells with the local immune system may regulate tissue homeostasis and the balance between tissue repair and fibrosis. Mesenchymal stromal cells (MSCs), in particular, may enhance the intrinsic reparative capabilities of the kidney. This Perspectives article considers the innate regenerative potential of the kidney in the context of ongoing studies of MSC therapy.

Enhanced Growth and Hepatic Differentiation of Fetal Liver Epithelial Cells through Combinational and Temporal Adjustment of Soluble Factors

PubMed Central

Qian, Lichuan; Krause, Diane S.; Saltzman, W. Mark

2012-01-01

Fetal liver epithelial cells (FLEC) are valuable for liver cell therapy and tissue engineering, but methods for culture and characterization of these cells are not well developed. This work explores the influence of multiple soluble factors on FLEC, with the long-term goal of developing an optimal culture system to generate functional liver tissue. Our comparative analysis suggests hepatocyte growth factor (HGF) is required throughout the culture period. In the presence of HGF, addition of oncostatin M (OSM) at culture initiation results in concurrent growth and maturation, while constant presence of protective agents like ascorbic acid enhances cell survival. Study observations led to the development of a culture medium that provided optimal growth and hepatic differentiation conditions. FLEC expansion was observed to be ~2 fold of that under standard conditions, albumin secretion rate was 2 – 3 times greater than maximal values obtained with other media, and the highest level of glycogen accumulation among all conditions was observed with the developed medium. Our findings serve to advance culture methods for liver progenitors in cell therapy and tissue engineering applications. PMID:21922669

Biomaterials and Tissue Engineering Strategies for Conjunctival Reconstruction and Dry Eye Treatment

PubMed Central

Lu, Qiaozhi; Al-Sheikh, Osama; Elisseeff, Jennifer H.; Grant, Michael P.

2015-01-01

The ocular surface is a component of the anterior segment of the eye and is covered by the tear film. Together, they protect the vital external components of the eye from the environment. Injuries, surgical trauma, and autoimmune diseases can damage this system, and in severe cases, tissue engineering strategies are necessary to ensure proper wound healing and recovery. Dry eye is another major concern and a complicated disease affecting the ocular surface. More effective and innovative therapies are required for better outcomes in treating dry eye. This review focuses on the regenerative medicine of the conjunctiva, which is an essential part of the ocular surface system. Features and advances of different types of biomolecular materials, and autologous and allogeneic tissue grafts are summarized and compared. Specifically, vitrigel, a collagen membrane and novel material for use on the ocular surface, offers significant advantages over other biomaterials. This review also discusses a breakthrough microfluidic technology, “organ-on-a-chip” and its potential application in investigating new therapies for dry eye. PMID:26692712

Three-Dimensional Printing Articular Cartilage: Recapitulating the Complexity of Native Tissue.

PubMed

Guo, Ting; Lembong, Josephine; Zhang, Lijie Grace; Fisher, John P

2017-06-01

In the past few decades, the field of tissue engineering combined with rapid prototyping (RP) techniques has been successful in creating biological substitutes that mimic tissues. Its applications in regenerative medicine have drawn efforts in research from various scientific fields, diagnostics, and clinical translation to therapies. While some areas of therapeutics are well developed, such as skin replacement, many others such as cartilage repair can still greatly benefit from tissue engineering and RP due to the low success and/or inefficiency of current existing, often surgical treatments. Through fabrication of complex scaffolds and development of advanced materials, RP provides a new avenue for cartilage repair. Computer-aided design and three-dimensional (3D) printing allow the fabrication of modeled cartilage scaffolds for repair and regeneration of damaged cartilage tissues. Specifically, the various processes of 3D printing will be discussed in details, both cellular and acellular techniques, covering the different materials, geometries, and operational printing conditions for the development of tissue-engineered articular cartilage. Finally, we conclude with some insights on future applications and challenges related to this technology, especially using 3D printing techniques to recapitulate the complexity of native structure for advanced cartilage regeneration.

Proresolving Nanomedicines Activate Bone Regeneration in Periodontitis

PubMed Central

Hasturk, H.; Kantarci, A.; Freire, M.O.; Nguyen, D.; Dalli, J.; Serhan, C.N.

2015-01-01

Therapies to reverse tissue damage from osteolytic inflammatory diseases are limited by the inability of current tissue-engineering procedures to restore lost hard and soft tissues. There is a critical need for new therapeutics in regeneration. In addition to scaffolds, cells, and soluble mediators necessary for tissue engineering, control of endogenous inflammation is an absolute requirement for success. Although significant progress has been made in understanding natural resolution of inflammation pathways to limit uncontrolled inflammation in disease, harnessing the biomimetic properties of proresolving lipid mediators has not been demonstrated. Here, we report the use of nano-proresolving medicines (NPRM) containing a novel lipoxin analog (benzo-lipoxin A4, bLXA4) to promote regeneration of hard and soft tissues irreversibly lost to periodontitis in the Hanford miniature pig. In this proof-of-principle experiment, NPRM-bLXA4 dramatically reduced inflammatory cell infiltrate into chronic periodontal disease sites treated surgically and dramatically increased new bone formation and regeneration of the periodontal organ. These findings indicate that NPRM-bLXA4 is a mimetic of endogenous resolving mechanisms with potent bioactions that offers a new therapeutic tissue-engineering approach for the treatment of chronic osteolytic inflammatory diseases. PMID:25389003

Proresolving nanomedicines activate bone regeneration in periodontitis.

PubMed

Van Dyke, T E; Hasturk, H; Kantarci, A; Freire, M O; Nguyen, D; Dalli, J; Serhan, C N

2015-01-01

Therapies to reverse tissue damage from osteolytic inflammatory diseases are limited by the inability of current tissue-engineering procedures to restore lost hard and soft tissues. There is a critical need for new therapeutics in regeneration. In addition to scaffolds, cells, and soluble mediators necessary for tissue engineering, control of endogenous inflammation is an absolute requirement for success. Although significant progress has been made in understanding natural resolution of inflammation pathways to limit uncontrolled inflammation in disease, harnessing the biomimetic properties of proresolving lipid mediators has not been demonstrated. Here, we report the use of nano-proresolving medicines (NPRM) containing a novel lipoxin analog (benzo-lipoxin A4, bLXA4) to promote regeneration of hard and soft tissues irreversibly lost to periodontitis in the Hanford miniature pig. In this proof-of-principle experiment, NPRM-bLXA4 dramatically reduced inflammatory cell infiltrate into chronic periodontal disease sites treated surgically and dramatically increased new bone formation and regeneration of the periodontal organ. These findings indicate that NPRM-bLXA4 is a mimetic of endogenous resolving mechanisms with potent bioactions that offers a new therapeutic tissue-engineering approach for the treatment of chronic osteolytic inflammatory diseases. © International & American Associations for Dental Research 2014.

3D Bioprinting for Engineering Complex Tissues

PubMed Central

Mandrycky, Christian; Wang, Zongjie; Kim, Keekyoung; Kim, Deok-Ho

2016-01-01

Bioprinting is a 3D fabrication technology used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. While still in its early stages, bioprinting strategies have demonstrated their potential use in regenerative medicine to generate a variety of transplantable tissues, including skin, cartilage, and bone. However, current bioprinting approaches still have technical challenges in terms of high-resolution cell deposition, controlled cell distributions, vascularization, and innervation within complex 3D tissues. While no one-size-fits-all approach to bioprinting has emerged, it remains an on-demand, versatile fabrication technique that may address the growing organ shortage as well as provide a high-throughput method for cell patterning at the micrometer scale for broad biomedical engineering applications. In this review, we introduce the basic principles, materials, integration strategies and applications of bioprinting. We also discuss the recent developments, current challenges and future prospects of 3D bioprinting for engineering complex tissues. Combined with recent advances in human pluripotent stem cell technologies, 3D-bioprinted tissue models could serve as an enabling platform for high-throughput predictive drug screening and more effective regenerative therapies. PMID:26724184

3D bioprinting for engineering complex tissues.

PubMed

Mandrycky, Christian; Wang, Zongjie; Kim, Keekyoung; Kim, Deok-Ho

2016-01-01

Bioprinting is a 3D fabrication technology used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. While still in its early stages, bioprinting strategies have demonstrated their potential use in regenerative medicine to generate a variety of transplantable tissues, including skin, cartilage, and bone. However, current bioprinting approaches still have technical challenges in terms of high-resolution cell deposition, controlled cell distributions, vascularization, and innervation within complex 3D tissues. While no one-size-fits-all approach to bioprinting has emerged, it remains an on-demand, versatile fabrication technique that may address the growing organ shortage as well as provide a high-throughput method for cell patterning at the micrometer scale for broad biomedical engineering applications. In this review, we introduce the basic principles, materials, integration strategies and applications of bioprinting. We also discuss the recent developments, current challenges and future prospects of 3D bioprinting for engineering complex tissues. Combined with recent advances in human pluripotent stem cell technologies, 3D-bioprinted tissue models could serve as an enabling platform for high-throughput predictive drug screening and more effective regenerative therapies. Copyright © 2015 Elsevier Inc. All rights reserved.

Adipose Tissue-Derived Pericytes for Cartilage Tissue Engineering.

PubMed

Zhang, Jinxin; Du, Chunyan; Guo, Weimin; Li, Pan; Liu, Shuyun; Yuan, Zhiguo; Yang, Jianhua; Sun, Xun; Yin, Heyong; Guo, Quanyi; Zhou, Chenfu

2017-01-01

Mesenchymal stem cells (MSCs) represent a promising alternative source for cartilage tissue engineering. However, MSC culture is labor-intensive, so these cells cannot be applied immediately to regenerate cartilage for clinical purposes. Risks during the ex vivo expansion of MSCs, such as infection and immunogenicity, can be a bottleneck in their use in clinical tissue engineering. As a novel stem cell source, pericytes are generally considered to be the origin of MSCs. Pericytes do not have to undergo time-consuming ex vivo expansion because they are uncultured cells. Adipose tissue is another optimal stem cell reservoir. Because adipose tissue is well vascularized, a considerable number of pericytes are located around blood vessels in this accessible and dispensable tissue, and autologous pericytes can be applied immediately for cartilage regeneration. Thus, we suggest that adipose tissue-derived pericytes are promising seed cells for cartilage regeneration. Many studies have been performed to develop isolation methods for the adipose tissuederived stromal vascular fraction (AT-SVF) using lipoaspiration and sorting pericytes from AT-SVF. These methods are useful for sorting a large number of viable pericytes for clinical therapy after being combined with automatic isolation using an SVF device and automatic magnetic-activated cell sorting. These tools should help to develop one-step surgery for repairing cartilage damage. However, the use of adipose tissue-derived pericytes as a cell source for cartilage tissue engineering has not drawn sufficient attention and preclinical studies are needed to improve cell purity, to increase sorting efficiency, and to assess safety issues of clinical applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Regeneration of urologic tissues and organs.

PubMed

Atala, Anthony

2005-01-01

Patients suffering from a variety of urologic diseases may be treated with transplanted tissues and organs. However, there is a shortage of donor tissues and organs, which is worsening yearly owing to the ageing population. Scientists in the field of regenerative medicine and tissue engineering are applying the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured urologic tissues. This chapter reviews recent advances that have occurred in the regeneration of urologic organs and describes how these applications may offer novel therapies for patients with urologic disease.

Nanomaterials design and tests for neural tissue engineering.

PubMed

Saracino, Gloria A A; Cigognini, Daniela; Silva, Diego; Caprini, Andrea; Gelain, Fabrizio

2013-01-07

Nanostructured scaffolds recently showed great promise in tissue engineering: nanomaterials can be tailored at the molecular level and scaffold morphology may more closely resemble features of extracellular matrix components in terms of porosity, framing and biofunctionalities. As a consequence, both biomechanical properties of scaffold microenvironments and biomaterial-protein interactions can be tuned, allowing for improved transplanted cell engraftment and better controlled diffusion of drugs. Easier said than done, a nanotech-based regenerative approach encompasses different fields of know-how, ranging from in silico simulations, nanomaterial synthesis and characterization at the nano-, micro- and mesoscales to random library screening methods (e.g. phage display), in vitro cellular-based experiments and validation in animal models of the target injury. All of these steps of the "assembly line" of nanostructured scaffolds are tightly interconnected both in their standard analysis techniques and in their most recent breakthroughs: indeed their efforts have to jointly provide the deepest possible analyses of the diverse facets of the challenging field of neural tissue engineering. The purpose of this review is therefore to provide a critical overview of the recent advances in and drawbacks and potential of each mentioned field, contributing to the realization of effective nanotech-based therapies for the regeneration of peripheral nerve transections, spinal cord injuries and brain traumatic injuries. Far from being the ultimate overview of such a number of topics, the reader will acknowledge the intrinsic complexity of the goal of nanotech tissue engineering for a conscious approach to the development of a regenerative therapy and, by deciphering the thread connecting all steps of the research, will gain the necessary view of its tremendous potential if each piece of stone is correctly placed to work synergically in this impressive mosaic.

Osteoimmune Mechanisms of Segmental Bone Fracture Healing and Therapy

DTIC Science & Technology

2016-09-01

to civilians. Despite efforts involving allografts , surgery and fixators, intramedullary nailing and invasive plate fixing to heal segmental...efforts are focused on: tissue engineering approaches aimed at developing osteoconductive scaffolds, better quality synthetic bone grafts, and use of

Finite Element Method (FEM), Mechanobiology and Biomimetic Scaffolds in Bone Tissue Engineering

PubMed Central

Boccaccio, A.; Ballini, A.; Pappalettere, C.; Tullo, D.; Cantore, S.; Desiate, A.

2011-01-01

Techniques of bone reconstructive surgery are largely based on conventional, non-cell-based therapies that rely on the use of durable materials from outside the patient's body. In contrast to conventional materials, bone tissue engineering is an interdisciplinary field that applies the principles of engineering and life sciences towards the development of biological substitutes that restore, maintain, or improve bone tissue function. Bone tissue engineering has led to great expectations for clinical surgery or various diseases that cannot be solved with traditional devices. For example, critical-sized defects in bone, whether induced by primary tumor resection, trauma, or selective surgery have in many cases presented insurmountable challenges to the current gold standard treatment for bone repair. The primary purpose of bone tissue engineering is to apply engineering principles to incite and promote the natural healing process of bone which does not occur in critical-sized defects. The total market for bone tissue regeneration and repair was valued at $1.1 billion in 2007 and is projected to increase to nearly $1.6 billion by 2014. Usually, temporary biomimetic scaffolds are utilized for accommodating cell growth and bone tissue genesis. The scaffold has to promote biological processes such as the production of extra-cellular matrix and vascularisation, furthermore the scaffold has to withstand the mechanical loads acting on it and to transfer them to the natural tissues located in the vicinity. The design of a scaffold for the guided regeneration of a bony tissue requires a multidisciplinary approach. Finite element method and mechanobiology can be used in an integrated approach to find the optimal parameters governing bone scaffold performance. In this paper, a review of the studies that through a combined use of finite element method and mechano-regulation algorithms described the possible patterns of tissue differentiation in biomimetic scaffolds for bone tissue engineering is given. Firstly, the generalities of the finite element method of structural analysis are outlined; second, the issues related to the generation of a finite element model of a given anatomical site or of a bone scaffold are discussed; thirdly, the principles on which mechanobiology is based, the principal theories as well as the main applications of mechano-regulation models in bone tissue engineering are described; finally, the limitations of the mechanobiological models and the future perspectives are indicated. PMID:21278921

Living cardiac patch: the elixir for cardiac regeneration.

PubMed

Lakshmanan, Rajesh; Krishnan, Uma Maheswari; Sethuraman, Swaminathan

2012-12-01

A thorough understanding of the cellular and muscle fiber orientation in left ventricular cardiac tissue is of paramount importance for the generation of artificial cardiac patches to treat the ischemic myocardium. The major challenge faced during cardiac patch engineering is to choose a perfect combination of three entities; cells, scaffolds and signaling molecules comprising the tissue engineering triad for repair and regeneration. This review provides an overview of various scaffold materials, their mechanical properties and fabrication methods utilized in cardiac patch engineering. Stem cell therapies in clinical trials and the commercially available cardiac patch materials were summarized in an attempt to provide a recent perspective in the treatment of heart failure. Various tissue engineering strategies employed thus far to construct viable thick cardiac patches is schematically illustrated. Though many strategies have been proposed for fabrication of various cardiac scaffold materials, the stage and severity of the disease condition demands the incorporation of additional cues in a suitable scaffold material. The scaffold may be nanofibrous patch, hydrogel or custom designed films. Integration of stem cells and biomolecular cues along with the scaffold may provide the right microenvironment for the repair of unhealthy left ventricular tissue as well as promote its regeneration.

Emerging Perspectives in Scaffold for Tissue Engineering in Oral Surgery.

PubMed

Ceccarelli, Gabriele; Presta, Rossella; Benedetti, Laura; Cusella De Angelis, Maria Gabriella; Lupi, Saturnino Marco; Rodriguez Y Baena, Ruggero

2017-01-01

Bone regeneration is currently one of the most important and challenging tissue engineering approaches in regenerative medicine. Bone regeneration is a promising approach in dentistry and is considered an ideal clinical strategy in treating diseases, injuries, and defects of the maxillofacial region. Advances in tissue engineering have resulted in the development of innovative scaffold designs, complemented by the progress made in cell-based therapies. In vitro bone regeneration can be achieved by the combination of stem cells, scaffolds, and bioactive factors. The biomimetic approach to create an ideal bone substitute provides strategies for developing combined scaffolds composed of adult stem cells with mesenchymal phenotype and different organic biomaterials (such as collagen and hyaluronic acid derivatives) or inorganic biomaterials such as manufactured polymers (polyglycolic acid (PGA), polylactic acid (PLA), and polycaprolactone). This review focuses on different biomaterials currently used in dentistry as scaffolds for bone regeneration in treating bone defects or in surgical techniques, such as sinus lift, horizontal and vertical bone grafts, or socket preservation. Our review would be of particular interest to medical and surgical researchers at the interface of cell biology, materials science, and tissue engineering, as well as industry-related manufacturers and researchers in healthcare, prosthetics, and 3D printing, too.

A Review of the Responses of Two- and Three-Dimensional Engineered Tissues to Electric Fields

PubMed Central

Hronik-Tupaj, Marie

2012-01-01

The application of external biophysical signals is one approach to tissue engineering that is explored less often than more traditional additions of exogenous biochemical and chemical factors to direct cell and tissue outcomes. The study of bioelectromagnetism and the field of electrotherapeutics have evolved over the years, and we review biocompatible electric stimulation devices and their successful application to tissue growth. Specifically, information on capacitively coupled alternating current, inductively coupled alternating current, and direct current devices is described. Cell and tissue responses from the application of these devices, including two- and three-dimensional in vitro studies and in vivo studies, are reviewed with regard to cell proliferation, adhesion, differentiation, morphology, and migration and tissue function. The current understanding of cellular mechanisms related to electric stimulation is detailed. The advantages of electric stimulation are compared with those pf other techniques, and areas in which electric fields are used as an adjuvant therapy for healing and regeneration are discussed. PMID:22046979

Leveraging “Raw Materials” as Building Blocks and Bioactive Signals in Regenerative Medicine

PubMed Central

Renth, Amanda N.

2012-01-01

Components found within the extracellular matrix (ECM) have emerged as an essential subset of biomaterials for tissue engineering scaffolds. Collagen, glycosaminoglycans, bioceramics, and ECM-based matrices are the main categories of “raw materials” used in a wide variety of tissue engineering strategies. The advantages of raw materials include their inherent ability to create a microenvironment that contains physical, chemical, and mechanical cues similar to native tissue, which prove unmatched by synthetic biomaterials alone. Moreover, these raw materials provide a head start in the regeneration of tissues by providing building blocks to be bioresorbed and incorporated into the tissue as opposed to being biodegraded into waste products and removed. This article reviews the strategies and applications of employing raw materials as components of tissue engineering constructs. Utilizing raw materials holds the potential to provide both a scaffold and a signal, perhaps even without the addition of exogenous growth factors or cytokines. Raw materials contain endogenous proteins that may also help to improve the translational success of tissue engineering solutions to progress from laboratory bench to clinical therapies. Traditionally, the tissue engineering triad has included cells, signals, and materials. Whether raw materials represent their own new paradigm or are categorized as a bridge between signals and materials, it is clear that they have emerged as a leading strategy in regenerative medicine. The common use of raw materials in commercial products as well as their growing presence in the research community speak to their potential. However, there has heretofore not been a coordinated or organized effort to classify these approaches, and as such we recommend that the use of raw materials be introduced into the collective consciousness of our field as a recognized classification of regenerative medicine strategies. PMID:22462759

3D Printing of Personalized Organs and Tissues

NASA Astrophysics Data System (ADS)

Ye, Kaiming

2015-03-01

Authors: Kaiming Ye and Sha Jin, Department of Biomedical Engineering, Watson School of Engineering and Applied Science, Binghamton University, State University of New York, Binghamton, NY 13902-6000 Abstract: Creation of highly organized multicellular constructs, including tissues and organs or organoids, will revolutionize tissue engineering and regenerative medicine. The development of these technologies will enable the production of individualized organs or tissues for patient-tailored organ transplantation or cell-based therapy. For instance, a patient with damaged myocardial tissues due to an ischemic event can receive a myocardial transplant generated using the patient's own induced pluripotent stem cells (iPSCs). Likewise, a type-1 diabetic patient can be treated with lab-generated islets to restore his or her physiological insulin secretion capability. These lab-produced, high order tissues or organs can also serve as disease models for pathophysiological study and drug screening. The remarkable advances in stem cell biology, tissue engineering, microfabrication, and materials science in the last decade suggest the feasibility of generating these tissues and organoids in the laboratory. Nevertheless, major challenges still exist. One of the critical challenges that we still face today is the difficulty in constructing or fabricating multicellular assemblies that recapitulate in vivo microenvironments essential for controlling cell proliferation, migration, differentiation, maturation and assembly into a biologically functional tissue or organoid structure. These challenges can be addressed through developing 3D organ and tissue printing which enables organizing and assembling cells into desired tissue and organ structures. We have shown that human pluripotent stem cells differentiated in 3D environments are mature and possess high degree of biological function necessary for them to function in vivo.

Nanotechnology as an adjunct tool for transplanting engineered cells and tissues.

PubMed

Borlongan, Cesar V; Masuda, Tadashi; Walker, Tiffany A; Maki, Mina; Hara, Koichi; Yasuhara, Takao; Matsukawa, Noriyuki; Emerich, Dwaine F

2007-11-01

Laboratory and clinical studies have provided evidence of feasibility, safety and efficacy of cell transplantation to treat a wide variety of diseases characterized by tissue and cell dysfunction ranging from diabetes to spinal cord injury. However, major hurdles remain and limit pursuing large clinical trials, including the availability of a universal cell source that can be differentiated into specific cellular phenotypes, methods to protect the transplanted allogeneic or xenogeneic cells from rejection by the host immune system, techniques to enhance cellular integration of the transplant within the host tissue, strategies for in vivo detection and monitoring of the cellular implants, and new techniques to deliver genes to cells without eliciting a host immune response. Finding ways to circumvent these obstacles will benefit considerably from being able to understand, visualize, and control cellular interactions at a sub-micron level. Cutting-edge discoveries in the multidisciplinary field of nanotechnology have provided us a platform to manipulate materials, tissues, cells, and DNA at the level of and within the individual cell. Clearly, the scientific innovations achieved with nanotechnology are a welcome strategy for enhancing the generally encouraging results already achieved in cell transplantation. This review article discusses recent progress in the field of nanotechnology as a tool for tissue engineering, gene therapy, cell immunoisolation, and cell imaging, highlighting its direct applications in cell transplantation therapy.

Advances in Cell and Gene-based Therapies for Cystic Fibrosis Lung Disease

PubMed Central

Oakland, Mayumi; Sinn, Patrick L; McCray Jr, Paul B

2012-01-01

Cystic fibrosis (CF) is a disease characterized by airway infection, inflammation, remodeling, and obstruction that gradually destroy the lungs. Direct delivery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene to airway epithelia may offer advantages, as the tissue is accessible for topical delivery of vectors. Yet, physical and host immune barriers in the lung present challenges for successful gene transfer to the respiratory tract. Advances in gene transfer approaches, tissue engineering, and novel animal models are generating excitement within the CF research field. This review discusses current challenges and advancements in viral and nonviral vectors, cell-based therapies, and CF animal models. PMID:22371844

Tissue engineering of bladder using vascular endothelial growth factor gene-modified endothelial progenitor cells.

PubMed

Chen, Bai-Song; Xie, Hua; Zhang, Sheng-Li; Geng, Hong-Quan; Zhou, Jun-Mei; Pan, Jun; Chen, Fang

2011-12-01

This study assessed the use of vascular endothelial growth factor (VEGF) gene-modified endothelial progenitor cells (EPCs) seeded onto bladder acellular matrix grafts (BAMGs), to enhance the blood supply in tissue-engineered bladders in a porcine model. Autologous porcine peripheral EPCs were isolated, cultured, expanded, characterized, and modified with the VEGF gene using an adenovirus vector. The expression of VEGF was examined using reverse transcriptase polymerase chain reaction (RT-PCR) and an enzyme-linked immunosorbent assay (ELISA). VEGF gene modified EPCs were seeded onto BAMG and cultured for 3 days before implantation into pigs for bladder tissue engineering. A partial bladder cystectomy was performed in 12 pigs. The experimental group (6 pigs) received VEGF gene-modified EPC-seeded BAMG. The control group (6 pigs) received BAMG without seeded EPCs. The resulting tissue-engineered bladders were subject to a general and histological analysis. Microvessel density (MVD) was assessed using immunohistochemistry. The ex vivo transfection efficiency of EPCs was greater than 60%-70% when concentrated adenovirus was used. The genetically modified cells expressed both VEGF and green fluorescent protein (GFP). Scanning electron microscopy (SEM) and Masson's trichrome staining of cross sections of the cultured cells seeded to BAMG showed cell attachment and proliferation on the surface of the BAMG. Histological examination revealed bladder regeneration in a time-dependent fashion. Significant increases in MVD were observed in the experimental group, in comparison with the control group. VEGF-modified EPCs significantly enhanced neovascularization, compared with BAMG alone. These results indicate that EPCs, combined with VEGF gene therapy, may be a suitable approach for increasing blood supply in the tissue engineering of bladders. Thus, a useful strategy to achieve a tissue-engineered bladder is indicated.

Pluripotent Stem Cells for Retinal Tissue Engineering: Current Status and Future Prospects.

PubMed

Singh, Ratnesh; Cuzzani, Oscar; Binette, François; Sternberg, Hal; West, Michael D; Nasonkin, Igor O

2018-04-19

The retina is a very fine and layered neural tissue, which vitally depends on the preservation of cells, structure, connectivity and vasculature to maintain vision. There is an urgent need to find technical and biological solutions to major challenges associated with functional replacement of retinal cells. The major unmet challenges include generating sufficient numbers of specific cell types, achieving functional integration of transplanted cells, especially photoreceptors, and surgical delivery of retinal cells or tissue without triggering immune responses, inflammation and/or remodeling. The advances of regenerative medicine enabled generation of three-dimensional tissues (organoids), partially recreating the anatomical structure, biological complexity and physiology of several tissues, which are important targets for stem cell replacement therapies. Derivation of retinal tissue in a dish creates new opportunities for cell replacement therapies of blindness and addresses the need to preserve retinal architecture to restore vision. Retinal cell therapies aimed at preserving and improving vision have achieved many improvements in the past ten years. Retinal organoid technologies provide a number of solutions to technical and biological challenges associated with functional replacement of retinal cells to achieve long-term vision restoration. Our review summarizes the progress in cell therapies of retina, with focus on human pluripotent stem cell-derived retinal tissue, and critically evaluates the potential of retinal organoid approaches to solve a major unmet clinical need-retinal repair and vision restoration in conditions caused by retinal degeneration and traumatic ocular injuries. We also analyze obstacles in commercialization of retinal organoid technology for clinical application.

Future potentials for using osteogenic stem cells and biomaterials in orthopedics.

PubMed

Oreffo, R O; Triffitt, J T

1999-08-01

Ideal skeletal reconstruction depends on regeneration of normal tissues that result from initiation of progenitor cell activity. However, knowledge of the origins and phenotypic characteristics of these progenitors and the controlling factors that govern bone formation and remodeling to give a functional skeleton adequate for physiological needs is limited. Practical methods are currently being investigated to amplify in in vitro culture the appropriate autologous cells to aid skeletal healing and reconstruction. Recent advances in the fields of biomaterials, biomimetics, and tissue engineering have focused attention on the potentials for clinical application. Current cell therapy procedures include the use of tissue-cultured skin cells for treatment of burns and ulcers, and in orthopedics, the use of cultured cartilage cells for articular defects. As mimicry of natural tissues is the goal, a fuller understanding of the development, structures, and functions of normal tissues is necessary. Practically all tissues are capable of being repaired by tissue engineering principles. Basic requirements include a scaffold conducive to cell attachment and maintenance of cell function, together with a rich source of progenitor cells. In the latter respect, bone is a special case and there is a vast potential for regeneration from cells with stem cell characteristics. The development of osteoblasts, chondroblasts, adipoblasts, myoblasts, and fibroblasts results from colonies derived from such single cells. They may thus, theoretically, be useful for regeneration of all tissues that this variety of cells comprise: bone, cartilage, fat, muscle, tendons, and ligaments. Also relevant to tissue reconstruction is the field of genetic engineering, which as a principal step in gene therapy would be the introduction of a functional specific human DNA into cells of a patient with a genetic disease that affects mainly a particular tissue or organ. Such a situation is pertinent to osteogenesis imperfecta, for example, where in more severely affected individuals any improvements in long bone quality would be beneficial to the patient. In conclusion, the potentials for using osteogenic stem cells and biomaterials in orthopedics for skeletal healing is immense, and work in this area is likely to expand significantly in the future.

Magnetically controllable 3D microtissues based on magnetic microcryogels.

PubMed

Liu, Wei; Li, Yaqian; Feng, Siyu; Ning, Jia; Wang, Jingyu; Gou, Maling; Chen, Huijun; Xu, Feng; Du, Yanan

2014-08-07

Microtissues on the scale of several hundred microns are a promising cell culture configuration resembling the functional tissue units in vivo. In contrast to conventional cell culture, handling of microtissues poses new challenges such as medium exchange, purification and maintenance of the microtissue integrity. Here, we developed magnetic microcryogels to assist microtissue formation with enhanced controllability and robustness. The magnetic microcryogels were fabricated on-chip by cryogelation and micro-molding which could endure extensive external forces such as fluidic shear stress during pipetting and syringe injection. The magnetically controllable microtissues were applied to constitute a novel separable 3D co-culture system realizing functional enhancement of the hepatic microtissues co-cultured with the stromal microtissues and easy purification of the hepatic microtissues for downstream drug testing. The magnetically controllable microtissues with pre-defined shapes were also applied as building blocks to accelerate the tissue assembly process under magnetic force for bottom-up tissue engineering. Finally, the magnetic microcryogels could be injected in vivo as cell delivery vehicles and tracked by MRI. The injectable magnetic microtissues maintained viability at the injection site indicating good retention and potential applications for cell therapy. The magnetic microcryogels are expected to significantly promote the microtissues as a promising cellular configuration for cell-based applications such as in drug testing, tissue engineering and regenerative therapy.

Applications of Cell Microencapsulation.

PubMed

Opara, Emmanuel C

2017-01-01

The goal of this chapter is to provide an overview of the different purposes for which the cell microencapsulation technology can be used. These include immunoisolation of non-autologous cells used for cell therapy; immobilization of cells for localized (targeted) delivery of therapeutic products to ablate, repair, or regenerate tissue; simultaneous delivery of multiple therapeutic agents in cell therapy; spatial compartmentalization of cells in complex tissue engineering; expansion of cells in culture; and production of different probiotics and metabolites for industrial applications. For each of these applications, specific examples are provided to illustrate how the microencapsulation technology can be utilized to achieve the purpose. However, successful use of the cell microencapsulation technology for whatever purpose will ultimately depend upon careful consideration for the choice of the encapsulating polymers, the method of fabrication (cross-linking) of the microbeads, which affects the permselectivity, the biocompatibility and the mechanical strength of the microbeads as well as environmental parameters such as temperature, humidity, osmotic pressure, and storage solutions.The various applications discussed in this chapter are illustrated in the different chapters of this book and where appropriate relevant images of the microencapsulation products are provided. It is hoped that this outline of the different applications of cell microencapsulation would provide a good platform for tissue engineers, scientists, and clinicians to design novel tissue constructs and products for therapeutic and industrial applications.

3D engineered cardiac tissue models of human heart disease: learning more from our mice.

PubMed

Ralphe, J Carter; de Lange, Willem J

2013-02-01

Mouse engineered cardiac tissue constructs (mECTs) are a new tool available to study human forms of genetic heart disease within the laboratory. The cultured strips of cardiac cells generate physiologic calcium transients and twitch force, and respond to electrical pacing and adrenergic stimulation. The mECT can be made using cells from existing mouse models of cardiac disease, providing a robust readout of contractile performance and allowing a rapid assessment of genotype-phenotype correlations and responses to therapies. mECT represents an efficient and economical extension to the existing tools for studying cardiac physiology. Human ECTs generated from iPSCMs represent the next logical step for this technology and offer significant promise of an integrated, fully human, cardiac tissue model. Copyright © 2013. Published by Elsevier Inc.

Tissue engineering and regenerative medicine approaches to enhance the functional response to skeletal muscle injury.

PubMed

Sicari, Brian M; Dearth, Christopher L; Badylak, Stephen F

2014-01-01

The well-recognized ability of skeletal muscle for functional and structural regeneration following injury is severely compromised in degenerative diseases and in volumetric muscle loss. Tissue engineering and regenerative medicine strategies to support muscle reconstruction have typically been cell-centric with approaches that involve the exogenous delivery of cells with myogenic potential. These strategies have been limited by poor cell viability and engraftment into host tissue. Alternative approaches have involved the use of biomaterial scaffolds as substrates or delivery vehicles for exogenous myogenic progenitor cells. Acellular biomaterial scaffolds composed of mammalian extracellular matrix (ECM) have also been used as an inductive niche to promote the recruitment and differentiation of endogenous myogenic progenitor cells. An acellular approach, which activates or utilizes endogenous cell sources, obviates the need for exogenous cell administration and provides an advantage for clinical translation. The present review examines the state of tissue engineering and regenerative medicine therapies directed at augmenting the skeletal muscle response to injury and presents the pros and cons of each with respect to clinical translation. Copyright © 2013 Wiley Periodicals, Inc.

Messenger RNA Delivery for Tissue Engineering and Regenerative Medicine Applications.

PubMed

Patel, Siddharth; Athirasala, Avathamsa; Menezes, Paula P; Ashwanikumar, N; Zou, Ting; Sahay, Gaurav; Bertassoni, Luiz E

2018-06-07

The ability to control cellular processes and precisely direct cellular reprogramming has revolutionized regenerative medicine. Recent advances in in vitro transcribed (IVT) mRNA technology with chemical modifications have led to development of methods that control spatiotemporal gene expression. Additionally, there is a current thrust toward the development of safe, integration-free approaches to gene therapy for translational purposes. In this review, we describe strategies of synthetic IVT mRNA modifications and nonviral technologies for intracellular delivery. We provide insights into the current tissue engineering approaches that use a hydrogel scaffold with genetic material. Furthermore, we discuss the transformative potential of novel mRNA formulations that when embedded in hydrogels can trigger controlled genetic manipulation to regenerate tissues and organs in vitro and in vivo. The role of mRNA delivery in vascularization, cytoprotection, and Cas9-mediated xenotransplantation is additionally highlighted. Harmonizing mRNA delivery vehicle interactions with polymeric scaffolds can be used to present genetic cues that lead to precise command over cellular reprogramming, differentiation, and secretome activity of stem cells-an ultimate goal for tissue engineering.

On the nature of biomaterials.

PubMed

Williams, David F

2009-10-01

The situations in which biomaterials are currently used are vastly different to those of just a decade ago. Although implantable medical devices are still immensely important, medical technologies now encompass a range of drug and gene delivery systems, tissue engineering and cell therapies, organ printing and cell patterning, nanotechnology based imaging and diagnostic systems and microelectronic devices. These technologies still encompass metals, ceramics and synthetic polymers, but also biopolymers, self assembled systems, nanoparticles, carbon nanotubes and quantum dots. These changes imply that our original concepts of biomaterials and our expectations of their performance also have to change. This Leading Opinion Paper addresses these issues. It concludes that many substances which hitherto we may not have thought of as biomaterials should now be considered as such so that, alongside the traditional structural biomaterials, we have substances that have been engineered to perform functions within health care where their performance is directly controlled by interactions with tissues and tissue components. These include engineered tissues, cells, organs and even viruses. This essay develops the arguments for a radically different definition of a biomaterial.

Electrospinning: An enabling nanotechnology platform for drug delivery and regenerative medicine.

PubMed

Chen, Shixuan; Li, Ruiquan; Li, Xiaoran; Xie, Jingwei

2018-05-02

Electrospinning provides an enabling nanotechnology platform for generating a rich variety of novel structured materials in many biomedical applications including drug delivery, biosensing, tissue engineering, and regenerative medicine. In this review article, we begin with a thorough discussion on the method of producing 1D, 2D, and 3D electrospun nanofiber materials. In particular, we emphasize on how the 3D printing technology can contribute to the improvement of traditional electrospinning technology for the fabrication of 3D electrospun nanofiber materials as drug delivery devices/implants, scaffolds or living tissue constructs. We then highlight several notable examples of electrospun nanofiber materials in specific biomedical applications including cancer therapy, guiding cellular responses, engineering in vitro 3D tissue models, and tissue regeneration. Finally, we finish with conclusions and future perspectives of electrospun nanofiber materials for drug delivery and regenerative medicine. Copyright © 2018 Elsevier B.V. All rights reserved.

Clinical applications of decellularized extracellular matrices for tissue engineering and regenerative medicine.

PubMed

Parmaksiz, Mahmut; Dogan, Arin; Odabas, Sedat; Elçin, A Eser; Elçin, Y Murat

2016-03-17

Decellularization is the process of removing the cellular components from tissues or organs. It is a promising technology for obtaining a biomaterial with a highly preserved extracellular matrix (ECM), which may also act as a biological scaffold for tissue engineering and regenerative therapies. Decellularized products are gaining clinical importance and market space due to their ease of standardized production, constant availability for grafting and mechanical or biochemical superiority against competing clinical options, yielding clinical results ahead of the ones with autografts in some applications. Current drawbacks and limitations of traditional treatments and clinical applications can be overcome by using decellularized or acellular matrices. Several companies are leading the market with versatile acellular products designed for diverse use in the reconstruction of tissues and organs. This review describes ECM-based decellularized and acellular products that are currently in use for different branches of clinic.

Non-viral gene activated matrices for mesenchymal stem cells based tissue engineering of bone and cartilage.

PubMed

Raisin, Sophie; Belamie, Emmanuel; Morille, Marie

2016-10-01

Recent regenerative medicine and tissue engineering strategies for bone and cartilage repair have led to fascinating progress of translation from basic research to clinical applications. In this context, the use of gene therapy is increasingly being considered as an important therapeutic modality and regenerative technique. Indeed, in the last 20 years, nucleic acids (plasmid DNA, interferent RNA) have emerged as credible alternative or complement to proteins, which exhibited major issues including short half-life, loss of bioactivity in pathologic environment leading to high dose requirement and therefore high production costs. The relevance of gene therapy strategies in combination with a scaffold, following a so-called "Gene-Activated Matrix (GAM)" approach, is to achieve a direct, local and sustained delivery of nucleic acids from a scaffold to ensure efficient and durable cell transfection. Among interesting cells sources, Mesenchymal Stem Cells (MSC) are promising for a rational use in gene/cell therapy with more than 1700 clinical trials approved during the last decade. The aim of the present review article is to provide a comprehensive overview of recent and ongoing work in non-viral genetic engineering of MSC combined with scaffolds. More specifically, we will show how this inductive strategy can be applied to orient stem cells fate for bone and cartilage repair. Copyright © 2016 Elsevier Ltd. All rights reserved.

Whole-organ re-engineering: a regenerative medicine approach to digestive organ replacement.

PubMed

Yagi, Hiroshi; Soto-Gutierrez, Alejandro; Kitagawa, Yuko

2013-06-01

Recovery from end-stage organ failure presents a challenge for the medical community, considering the limitations of extracorporeal assist devices and the shortage of donors when organ replacement is needed. There is a need for new methods to promote recovery from organ failure and regenerative medicine is an option that should be considered. Recent progress in the field of tissue engineering has opened avenues for potential clinical applications, including the use of microfluidic devices for diagnostic purposes, and bioreactors or cell/tissue-based therapies for transplantation. Early attempts to engineer tissues produced thin, planar constructs; however, recent approaches using synthetic scaffolds and decellularized tissue have achieved a more complex level of tissue organization in organs such as the urinary bladder and trachea, with some success in clinical trials. In this context, the concept of decellularization technology has been applied to produce whole organ-derived scaffolds by removing cellular content while retaining all the necessary vascular and structural cues of the native organ. In this review, we focus on organ decellularization as a new regenerative medicine approach for whole organs, which may be applied in the field of digestive surgery.

Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy

PubMed Central

Gong, Ting; Heng, Boon Chin; Lo, Edward Chin Man; Zhang, Chengfei

2016-01-01

Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration. PMID:27069484

Recent advancements in carbon nanofiber and carbon nanotube applications in drug delivery and tissue engineering.

PubMed

Stout, David A

2015-01-01

Since the discovery and synthesis of carbon nanotubes (CNTs) and carbon nanofibers (CNFs) over a decade ago, researchers have envisioned and discovered new potential applications for these materials. CNTs and CNFs have rapidly become a platform technology for a variety of uses, including biomedical applications due to their mechanical, electrical, thermal, optical and structural properties. CNTs and CNFs are also advantageous due to their ability to be produced in many different shapes and sizes. Since their discovery, of the many imaginable applications, CNTs and CNFs have gained a significant amount of attention and therapeutic potential in tissue engineering and drug delivery applications. In recent years, CNTs and CNFs have made significant contributions in designing new strategies for, delivery of pharmaceuticals, genes and molecular probes into cells, stem cell therapies and assisting in tissue regeneration. Furthermore, it is widely expressed that these materials will significantly contribute to the next generation of health care technologies in treating diseases and contributing to tissue growth. Hence, this review seeks to explore the recent advancements, current status and limitations of CNTs and CNFs for drug delivery and tissue engineering applications.

Cartilage constructs engineered from chondrocytes overexpressing IGF-I improve the repair of osteochondral defects in a rabbit model.

PubMed

Madry, H; Kaul, G; Zurakowski, D; Vunjak-Novakovic, G; Cucchiarini, M

2013-04-16

Tissue engineering combined with gene therapy is a promising approach for promoting articular cartilage repair. Here, we tested the hypothesis that engineered cartilage with chondrocytes overexpressing a human insulin-like growth factor I (IGF-I) gene can enhance the repair of osteochondral defects, in a manner dependent on the duration of cultivation. Genetically modified chondrocytes were cultured on biodegradable polyglycolic acid scaffolds in dynamic flow rotating bioreactors for either 10 or 28 d. The resulting cartilaginous constructs were implanted into osteochondral defects in rabbit knee joints. After 28 weeks of in vivo implantation, immunoreactivity to ß-gal was detectable in the repair tissue of defects that received lacZ constructs. Engineered cartilaginous constructs based on IGF-I-overexpressing chondrocytes markedly improved osteochondral repair compared with control (lacZ) constructs. Moreover, IGF-I constructs cultivated for 28 d in vitro significantly promoted osteochondral repair vis-à-vis similar constructs cultivated for 10 d, leading to significantly decreased osteoarthritic changes in the cartilage adjacent to the defects. Hence, the combination of spatially defined overexpression of human IGF-I within a tissue-engineered construct and prolonged bioreactor cultivation resulted in most enhanced articular cartilage repair and reduction of osteoarthritic changes in the cartilage adjacent to the defect. Such genetically enhanced tissue engineering provides a versatile tool to evaluate potential therapeutic genes in vivo and to improve our comprehension of the development of the repair tissue within articular cartilage defects. Insights gained with additional exploration using this model may lead to more effective treatment options for acute cartilage defects.

CARTILAGE CONSTRUCTS ENGINEERED FROM CHONDROCYTES OVEREXPRESSING IGF-I IMPROVE THE REPAIR OF OSTEOCHONDRAL DEFECTS IN A RABBIT MODEL

PubMed Central

Madry, Henning; Kaul, Gunter; Zurakowski, David; Vunjak-Novakovic, Gordana; Cucchiarini, Magali

2015-01-01

Tissue engineering combined with gene therapy is a promising approach for promoting articular cartilage repair. Here, we tested the hypothesis that engineered cartilage with chondrocytes over expressing a human insulin-like growth factor I (IGF-I) gene can enhance the repair of osteochondral defects, in a manner dependent on the duration of cultivation. Genetically modified chondrocytes were cultured on biodegradable polyglycolic acid scaffolds in dynamic flow rotating bioreactors for either 10 or 28 d. The resulting cartilaginous constructs were implanted into osteochondral defects in rabbit knee joints. After 28 weeks of in vivo implantation, immunoreactivity to ß-gal was detectable in the repair tissue of defects that received lacZ constructs. Engineered cartilaginous constructs based on IGF-I-over expressing chondrocytes markedly improved osteochondral repair compared with control (lacZ) constructs. Moreover, IGF-I constructs cultivated for 28 d in vitro significantly promoted osteochondral repair vis-à-vis similar constructs cultivated for 10 d, leading to significantly decreased osteoarthritic changes in the cartilage adjacent to the defects. Hence, the combination of spatially defined overexpression of human IGF-I within a tissue-engineered construct and prolonged bioreactor cultivation resulted in most enhanced articular cartilage repair and reduction of osteoarthritic changes in the cartilage adjacent to the defect. Such genetically enhanced tissue engineering provides a versatile tool to evaluate potential therapeutic genes in vivo and to improve our comprehension of the development of the repair tissue within articular cartilage defects. Insights gained with additional exploration using this model may lead to more effective treatment options for acute cartilage defects. PMID:23588785

Current Methods for Skeletal Muscle Tissue Repair and Regeneration

PubMed Central

Liu, Juan; Saul, Dominik; Böker, Kai Oliver; Ernst, Jennifer; Lehman, Wolfgang

2018-01-01

Skeletal muscle has the capacity of regeneration after injury. However, for large volumes of muscle loss, this regeneration needs interventional support. Consequently, muscle injury provides an ongoing reconstructive and regenerative challenge in clinical work. To promote muscle repair and regeneration, different strategies have been developed within the last century and especially during the last few decades, including surgical techniques, physical therapy, biomaterials, and muscular tissue engineering as well as cell therapy. Still, there is a great need to develop new methods and materials, which promote skeletal muscle repair and functional regeneration. In this review, we give a comprehensive overview over the epidemiology of muscle tissue loss, highlight current strategies in clinical treatment, and discuss novel methods for muscle regeneration and challenges for their future clinical translation. PMID:29850487

Combinatorial biomatrix/cell-based therapies for restoration of host tissue architecture and function

PubMed Central

Cantu, David Antonio; Kao, W. John

2014-01-01

This Progress Report reviews recent advances in the utility of extracellular matrix (ECM)-mimic biomaterials in presenting and delivering therapeutic cells to promote tissue healing. This overview gives a brief introduction of different cell types being used in regenerative medicine and tissue engineering while addressing critical issues that must be overcome before cell-based approaches can be routinely employed in the clinic. A selection of 5 commonly used cell-associated, biomaterial platforms (collagen, hyaluronic acid, fibrin, alginate, and poly(ethylene glycol)) are reviewed for treatment of a number of acute injury or diseases with emphasis on animal models and clinical trials. This article concludes with current challenges and future perspectives regarding foreign body host response to biomaterials and immunological reactions to allogeneic or xenogeneic cells, vascularization and angiogenesis, matching mechanical strength and anisotropy of native tissues, as well as other non-technical issues regarding the clinical translation of biomatrix/cell-based therapies. PMID:23828863

Decoding the Regulatory Landscape of Ageing in Musculoskeletal Engineered Tissues Using Genome-Wide DNA Methylation and RNASeq

PubMed Central

Peffers, Mandy Jayne; Goljanek-Whysall, Katarzyna; Collins, John; Fang, Yongxiang; Rushton, Michael; Loughlin, John; Proctor, Carole; Clegg, Peter David

2016-01-01

Mesenchymal stem cells (MSC) are capable of multipotent differentiation into connective tissues and as such are an attractive source for autologous cell-based regenerative medicine and tissue engineering. Epigenetic mechanisms, like DNA methylation, contribute to the changes in gene expression in ageing. However there was a lack of sufficient knowledge of the role that differential methylation plays during chondrogenic, osteogenic and tenogenic differentiation from ageing MSCs. This study undertook genome level determination of the effects of DNA methylation on expression in engineered tissues from chronologically aged MSCs. We compiled unique DNA methylation signatures from chondrogenic, osteogenic, and tenogenic engineered tissues derived from young; n = 4 (21.8 years ± 2.4 SD) and old; n = 4 (65.5 years±8.3SD) human MSCs donors using the Illumina HumanMethylation 450 Beadchip arrays and compared these to gene expression by RNA sequencing. Unique and common signatures of global DNA methylation were identified. There were 201, 67 and 32 chondrogenic, osteogenic and tenogenic age-related DE protein-coding genes respectively. Findings inferred the nature of the transcript networks was predominantly for ‘cell death and survival’, ‘cell morphology’, and ‘cell growth and proliferation’. Further studies are required to validate if this gene expression effect translates to cell events. Alternative splicing (AS) was dysregulated in ageing with 119, 21 and 9 differential splicing events identified in chondrogenic, osteogenic and tenogenic respectively, and enrichment in genes associated principally with metabolic processes. Gene ontology analysis of differentially methylated loci indicated age-related enrichment for all engineered tissue types in ‘skeletal system morphogenesis’, ‘regulation of cell proliferation’ and ‘regulation of transcription’ suggesting that dynamic epigenetic modifications may occur in genes associated with shared and distinct pathways dependent upon engineered tissue type. An altered phenotype in engineered tissues was observed with ageing at numerous levels. These changes represent novel insights into the ageing process, with implications for stem cell therapies in older patients. In addition we have identified a number of tissue-dependant pathways, which warrant further studies. PMID:27533049

Recombinant proteins secreted from tissue-engineered bioartificial muscle improve cardiac dysfunction and suppress cardiomyocyte apoptosis in rats with heart failure.

PubMed

Rong, Shu-Ling; Wang, Yong-Jin; Wang, Xiao-Lin; Lu, Yong-Xin; Wu, Yin; Liu, Qi-Yun; Mi, Shao-Hua; Xu, Yu-Lan

2010-12-01

Tissue-engineered bioartificial muscle-based gene therapy represents a promising approach for the treatment of heart diseases. Experimental and clinical studies suggest that systemic administration of insulin-like growth factor-1 (IGF-1) protein or overexpression of IGF-1 in the heart exerts a favorable effect on cardiovascular function. This study aimed to investigate a chronic stage after myocardial infarction (MI) and the potential therapeutic effects of delivering a human IGF-1 gene by tissue-engineered bioartificial muscles (BAMs) following coronary artery ligation in Sprague-Dawley rats. Ligation of the left coronary artery or sham operation was performed. Primary skeletal myoblasts were retrovirally transduced to synthesize and secrete recombinant human insulin-like growth factor-1 (rhIGF-1), and green fluorescent protein (GFP), and tissue-engineered into implantable BAMs. The rats that underwent ligation were randomly assigned to 2 groups: MI-IGF group (n = 6) and MI-GFP group (n = 6). The MI-IGF group received rhIGF-secreting BAM (IGF-BAMs) transplantation, and the MI-GFP group received GFP-secreting BAM (GFP-BAMs) transplantation. Another group of rats served as the sham operation group, which was also randomly assigned to 2 subgroups: S-IGF group (n = 6) and S-GFP group (n = 6). The S-IGF group underwent IGF-1-BAM transplantation, and S-GFP group underwent GFP-BAM transplantation. IGF-1-BAMs and GFP-BAMs were implanted subcutaneously into syngeneic rats after two weeks of operation was performed. Four weeks after the treatment, hemodynamics was performed. IGF-1 was measured by radioimmunoassay, and then the rats were sacrificed and ventricular samples were subjected to immunohistochemistry. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to examine the mRNA expression of bax and Bcl-2. TNF-α and caspase 3 expression in myocardium was examined by Western blotting. Primary rat myoblasts were retrovirally transduced to secrete rhIGF-1 and tissue-engineered into implantable BAMs containing parallel arrays of postmitotic myofibers. In vitro, they secreted consistent levels of hIGF (0.4 - 1.2 µg×BAM(-1)×d(-1)). When implanted into syngeneic rat, IGF-BAMs secreted and delivered rhIGF. Four weeks after therapy, the hemodynamics was improved significantly in MI rats treated with IGF-BAMs compared with those treated with GFP-BAMs. The levels of serum IGF-1 were increased significantly in both MI and sham rats treated with IGF-BAM. The mRNA expression of bax was lower and Bcl-2 expression was higher in MI-IGF group than MI-GFP group (P < 0.05). Western blotting assay showed TNF-α and caspase 3 expression was lower in MI-IGF group than MI-GFP group after therapy. rhIGF-1 significantly improves left ventricular function and suppresses cardiomyocyte apoptosis in rats with chronic heart failure. Genetically modified tissue-engineered BAMs provide a method delivering recombinant protein for the treatment of heart failure.

Amniotic fluid stem cells: a promising therapeutic resource for cell-based regenerative therapy.

PubMed

Antonucci, Ivana; Pantalone, Andrea; Tete, Stefano; Salini, Vincenzo; Borlongan, Cesar V; Hess, David; Stuppia, Liborio

2012-01-01

Stem cells have been proposed as a powerful tool in the treatment of several human diseases, both for their ability to represent a source of new cells to replace those lost due to tissue injuries or degenerative diseases, and for the ability of produce trophic molecules able to minimize damage and promote recovery in the injured tissue. Different cell types, such as embryonic, fetal or adult stem cells, human fetal tissues and genetically engineered cell lines, have been tested for their ability to replace damaged cells and to restore the tissue function after transplantation. Amniotic fluid -derived Stem cells (AFS) are considered a novel resource for cell transplantation therapy, due to their high renewal capacity, the "in vitro" expression of embryonic cell lineage markers, and the ability to differentiate in tissues derived from all the three embryonic layers. Moreover, AFS do not produce teratomas when transplanted into animals and are characterized by a low antigenicity, which could represent an advantage for cell transplantation or cell replacement therapy. The present review focuses on the biological features of AFS, and on their potential use in the treatment of pathological conditions such as ischemic brain injury and bone damages.

3-D Bioprinting of Neural Tissue for Applications in Cell Therapy and Drug Screening

PubMed Central

Thomas, Michaela; Willerth, Stephanie M.

2017-01-01

Neurodegenerative diseases affect millions of individuals in North America and cost the health-care industry billions of dollars for treatment. Current treatment options for degenerative diseases focus on physical rehabilitation or drug therapies, which temporarily mask the effects of cell damage, but quickly lose their efficacy. Cell therapies for the central nervous system remain an untapped market due to the complexity involved in growing neural tissues, controlling their differentiation, and protecting them from the hostile environment they meet upon implantation. Designing tissue constructs for the discovery of better drug treatments are also limited due to the resolution needed for an accurate cellular representation of the brain, in addition to being expensive and difficult to translate to biocompatible materials. 3-D printing offers a streamlined solution for engineering brain tissue for drug discovery or, in the future, for implantation. New microfluidic and bioplotting devices offer increased resolution, little impact on cell viability and have been tested with several bioink materials including fibrin, collagen, hyaluronic acid, poly(caprolactone), and poly(ethylene glycol). This review details current efforts at bioprinting neural tissue and highlights promising avenues for future work. PMID:29204424

Synthetic Phage for Tissue Regeneration

PubMed Central

Merzlyak, Anna; Lee, Seung-Wuk

2014-01-01

Controlling structural organization and signaling motif display is of great importance to design the functional tissue regenerating materials. Synthetic phage, genetically engineered M13 bacteriophage has been recently introduced as novel tissue regeneration materials to display a high density of cell-signaling peptides on their major coat proteins for tissue regeneration purposes. Structural advantages of their long-rod shape and monodispersity can be taken together to construct nanofibrous scaffolds which support cell proliferation and differentiation as well as direct orientation of their growth in two or three dimensions. This review demonstrated how functional synthetic phage is designed and subsequently utilized for tissue regeneration that offers potential cell therapy. PMID:24991085

CAT--the new committee for advanced therapies at the European Medicines Agency.

PubMed

Celis, P

2010-01-01

The Regulation on Advanced Therapies (Regulation (EC) 1394/2007) establishes a new scientific committee, the Committee for Advanced Therapies (CAT), at the European Medicines Agency. The CAT is composed of experts in the field of Advanced Therapy Medicinal Products (ATMPs)--gene and cell therapy and tissue engineered products--and is responsible for the evaluation of the marketing authorisation applications for this novel class of products. The CAT is also involved in all scientific advice on ATMPs and in two new regulatory procedures for ATMPs, the classification and the certification procedures. The CAT will also play a key role in early contacts with developers of ATMPs.

Gene therapy and its implications in Periodontics

PubMed Central

Mahale, Swapna; Dani, Nitin; Ansari, Shumaila S.; Kale, Triveni

2009-01-01

Gene therapy is a field of Biomedicine. With the advent of gene therapy in dentistry, significant progress has been made in the control of periodontal diseases and reconstruction of dento-alveolar apparatus. Implementation in periodontics include: -As a mode of tissue engineering with three approaches: cell, protein-based and gene delivery approach. -Genetic approach to Biofilm Antibiotic Resistance. Future strategies of gene therapy in preventing periodontal diseases: -Enhances host defense mechanism against infection by transfecting host cells with an antimicrobial peptide protein-encoding gene. -Periodontal vaccination. Gene therapy is one of the recent entrants and its applications in the field of periodontics are reviewed in general here. PMID:20376232

Time-Dependent Recovery of Human Synovial Membrane Mesenchymal Stem Cell Function After High-Dose Steroid Therapy: Case Report and Laboratory Study.

PubMed

Yasui, Yukihiko; Hart, David A; Sugita, Norihiko; Chijimatsu, Ryota; Koizumi, Kota; Ando, Wataru; Moriguchi, Yu; Shimomura, Kazunori; Myoui, Akira; Yoshikawa, Hideki; Nakamura, Norimasa

2018-03-01

The use of mesenchymal stem cells from various tissue sources to repair injured tissues has been explored over the past decade in large preclinical models and is now moving into the clinic. To report the case of a patient who exhibited compromised mesenchymal stem cell (MSC) function shortly after use of high-dose steroid to treat Bell's palsy, who recovered 7 weeks after therapy. Case report and controlled laboratory study. A patient enrolled in a first-in-human clinical trial for autologous implantation of a scaffold-free tissue engineered construct (TEC) derived from synovial MSCs for chondral lesion repair had a week of high-dose steroid therapy for Bell's palsy. Synovial tissue was harvested for MSC preparation after a 3-week recovery period and again at 7 weeks after therapy. The MSC proliferation rates and cell surface marker expression profiles from the 3-week sample met conditions for further processing. However, the cells failed to generate a functional TEC. In contrast, MSCs harvested at 7 weeks after steroid therapy were functional in this regard. Further in vitro studies with MSCs and steroids indicated that the effect of in vivo steroids was likely a direct effect of the drug on the MSCs. This case suggests that MSCs are transiently compromised after high-dose steroid therapy and that careful consideration regarding timing of MSC harvest is critical. The drug profiles of MSC donors and recipients must be carefully monitored to optimize opportunities to successfully repair damaged tissues.

Human iPS cell-engineered cardiac tissue sheets with cardiomyocytes and vascular cells for cardiac regeneration

PubMed Central

Masumoto, Hidetoshi; Ikuno, Takeshi; Takeda, Masafumi; Fukushima, Hiroyuki; Marui, Akira; Katayama, Shiori; Shimizu, Tatsuya; Ikeda, Tadashi; Okano, Teruo; Sakata, Ryuzo; Yamashita, Jun K.

2014-01-01

To realize cardiac regeneration using human induced pluripotent stem cells (hiPSCs), strategies for cell preparation, tissue engineering and transplantation must be explored. Here we report a new protocol for the simultaneous induction of cardiomyocytes (CMs) and vascular cells [endothelial cells (ECs)/vascular mural cells (MCs)], and generate entirely hiPSC-engineered cardiovascular cell sheets, which showed advantageous therapeutic effects in infarcted hearts. The protocol adds to a previous differentiation protocol of CMs by using stage-specific supplementation of vascular endothelial cell growth factor for the additional induction of vascular cells. Using this cell sheet technology, we successfully generated physically integrated cardiac tissue sheets (hiPSC-CTSs). HiPSC-CTS transplantation to rat infarcted hearts significantly improved cardiac function. In addition to neovascularization, we confirmed that engrafted human cells mainly consisted of CMs in >40% of transplanted rats four weeks after transplantation. Thus, our HiPSC-CTSs show promise for cardiac regenerative therapy. PMID:25336194

Initial evaluation of vascular ingrowth into superporous hydrogels.

PubMed

Keskar, Vandana; Gandhi, Milind; Gemeinhart, Ernest J; Gemeinhart, Richard A

2009-08-01

There is a need for new materials and architectures for tissue engineering and regenerative medicine. Based upon our recent results developing novel scaffold architecture, we hypothesized that this new architecture would foster vascularization, a particular need for tissue engineering. We report on the potential of superporous hydrogel (SPH) scaffolds for in vivo cellular infiltration and vascularization. Poly(ethylene glycol) diacrylate (PEGDA) SPH scaffolds were implanted in the dorsum of severe combined immunodeficient (SCID) mice and harvested after 4 weeks of in vivo implantation. The SPHs were visibly red and vascularized, as apparent when compared to the non-porous hydrogel controls, which were macroscopically avascular. Host cell infiltration was observed throughout the SPHs. Blood cells and vascular structures, confirmed through staining for CD34 and smooth muscle alpha-actin, were observed throughout the scaffolds. This novel soft material may be utilized for cell transplantation, tissue engineering and in combination with cell therapies. The neovasularization and limited fibrotic response suggest that the architecture may be conducive to cell survival and rapid vessel development.

Additive Manufacturing of Vascular Grafts and Vascularized Tissue Constructs.

PubMed

Elomaa, Laura; Yang, Yunzhi Peter

2017-10-01

There is a great need for engineered vascular grafts among patients with cardiovascular diseases who are in need of bypass therapy and lack autologous healthy blood vessels. In addition, because of the severe worldwide shortage of organ donors, there is an increasing need for engineered vascularized tissue constructs as an alternative to organ transplants. Additive manufacturing (AM) offers great advantages and flexibility of fabrication of cell-laden, multimaterial, and anatomically shaped vascular grafts and vascularized tissue constructs. Various inkjet-, extrusion-, and photocrosslinking-based AM techniques have been applied to the fabrication of both self-standing vascular grafts and porous, vascularized tissue constructs. This review discusses the state-of-the-art research on the use of AM for vascular applications and the key criteria for biomaterials in the AM of both acellular and cellular constructs. We envision that new smart printing materials that can adapt to their environment and encourage rapid endothelialization and remodeling will be the key factor in the future for the successful AM of personalized and dynamic vascular tissue applications.

Engineering biosynthetic excitable tissues from unexcitable cells for electrophysiological and cell therapy studies

PubMed Central

Kirkton, Robert D.; Bursac, Nenad

2012-01-01

Patch-clamp recordings in single-cell expression systems have been traditionally used to study the function of ion channels. However, this experimental setting does not enable assessment of tissue-level function such as action potential (AP) conduction. Here we introduce a biosynthetic system that permits studies of both channel activity in single cells and electrical conduction in multicellular networks. We convert unexcitable somatic cells into an autonomous source of electrically excitable and conducting cells by stably expressing only three membrane channels. The specific roles that these expressed channels have on AP shape and conduction are revealed by different pharmacological and pacing protocols. Furthermore, we demonstrate that biosynthetic excitable cells and tissues can repair large conduction defects within primary 2- and 3-dimensional cardiac cell cultures. This approach enables novel studies of ion channel function in a reproducible tissue-level setting and may stimulate the development of new cell-based therapies for excitable tissue repair. PMID:21556054

ECM and ECM-like materials - Biomaterials for applications in regenerative medicine and cancer therapy.

PubMed

Hinderer, Svenja; Layland, Shannon Lee; Schenke-Layland, Katja

2016-02-01

Regenerative strategies such as stem cell-based therapies and tissue engineering applications are being developed with the aim to replace, remodel, regenerate or support damaged tissues and organs. In addition to careful cell type selection, the design of appropriate three-dimensional (3D) scaffolds is essential for the generation of bio-inspired replacement tissues. Such scaffolds are usually made of degradable or non-degradable biomaterials and can serve as cell or drug carriers. The development of more effective and efficient drug carrier systems is also highly relevant for novel cancer treatment strategies. In this review, we provide a summary of current approaches that employ ECM and ECM-like materials, or ECM-synthetic polymer hybrids, as biomaterials in the field of regenerative medicine. We further discuss the utilization of such materials for cell and drug delivery, and highlight strategies for their use as vehicles for cancer therapy. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Liver cell therapy and tissue engineering for transplantation.

PubMed

Vacanti, Joseph P; Kulig, Katherine M

2014-06-01

Liver transplantation remains the only definitive treatment for liver failure and is available to only a tiny fraction of patients with end-stage liver diseases. Major limitations for the procedure include donor organ shortage, high cost, high level of required expertise, and long-term consequences of immune suppression. Alternative cell-based liver therapies could potentially greatly expand the number of patients provided with effective treatment. Investigative research into augmenting or replacing liver function extends into three general strategies. Bioartificial livers (BALs) are extracorporeal devices that utilize cartridges of primary hepatocytes or cell lines to process patient plasma. Injection of liver cell suspensions aims to foster organ regeneration or provide a missing metabolic function arising from a genetic defect. Tissue engineering recreates the organ in vitro for subsequent implantation to augment or replace patient liver function. Translational models and clinical trials have highlighted both the immense challenges involved and some striking examples of success. Copyright © 2014. Published by Elsevier Inc.

An emerging cell-based strategy in orthopaedics: endothelial progenitor cells.

PubMed

Atesok, Kivanc; Matsumoto, Tomoyuki; Karlsson, Jon; Asahara, Takayuki; Atala, Anthony; Doral, M Nedim; Verdonk, Rene; Li, Ru; Schemitsch, Emil

2012-07-01

The purpose of this article was to analyze the results of studies in the literature, which evaluated the use of endothelial progenitor cells (EPCs) as a cell-based tissue engineering strategy. EPCs have been successfully used in regenerative medicine to augment neovascularization in patients after myocardial infarction and limb ischemia. EPCs' important role as vasculogenic progenitors presents them as a potential source for cell-based therapies to promote bone healing. EPCs have been shown to have prominent effects in promoting bone regeneration in several animal models. Evidence indicates that EPCs promote bone regeneration by stimulating both angiogenesis and osteogenesis through a differentiation process toward endothelial cell lineage and formation of osteoblasts. Moreover, EPCs increase vascularization and osteogenesis by increased secretion of growth factors and cytokines through paracrine mechanisms. EPCs offer the potential to emerge as a new strategy among other cell-based therapies to promote bone regeneration. Further investigations and human trials are required to address current questions with regard to biology and mechanisms of action of EPCs in bone tissue engineering.

Graphene supports in vitro proliferation and osteogenic differentiation of goat adult mesenchymal stem cells: potential for bone tissue engineering.

PubMed

Elkhenany, Hoda; Amelse, Lisa; Lafont, Andersen; Bourdo, Shawn; Caldwell, Marc; Neilsen, Nancy; Dervishi, Enkeleda; Derek, Oshin; Biris, Alexandru S; Anderson, David; Dhar, Madhu

2015-04-01

Current treatments for bone loss injuries involve autologous and allogenic bone grafts, metal alloys and ceramics. Although these therapies have proved useful, they suffer from inherent challenges, and hence, an adequate bone replacement therapy has not yet been found. We hypothesize that graphene may be a useful nanoscaffold for mesenchymal stem cells and will promote proliferation and differentiation into bone progenitor cells. In this study, we evaluate graphene, a biocompatible inert nanomaterial, for its effect on in vitro growth and differentiation of goat adult mesenchymal stem cells. Cell proliferation and differentiation are compared between polystyrene-coated tissue culture plates and graphene-coated plates. Graphitic materials are cytocompatible and support cell adhesion and proliferation. Importantly, cells seeded on to oxidized graphene films undergo osteogenic differentiation in fetal bovine serum-containing medium without the addition of any glucocorticoid or specific growth factors. These findings support graphene's potential to act as an osteoinducer and a vehicle to deliver mesenchymal stem cells, and suggest that the combination of graphene and goat mesenchymal stem cells provides a promising construct for bone tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd.

Grand challenges in bioengineered nanorobotics for cancer therapy.

PubMed

Lenaghan, Scott C; Wang, Yongzhong; Xi, Ning; Fukuda, Toshio; Tarn, Tzyhjong; Hamel, William R; Zhang, Mingjun

2013-03-01

One of the grand challenges currently facing engineering, life sciences, and medicine is the development of fully functional nanorobots capable of sensing, decision making, and actuation. These nanorobots may aid in cancer therapy, site-specific drug delivery, circulating diagnostics, advanced surgery, and tissue repair. In this paper, we will discuss, from a bioinspired perspective, the challenges currently facing nanorobotics, including core design, propulsion and power generation, sensing, actuation, control, decision making, and system integration. Using strategies inspired from microorganisms, we will discuss a potential bioengineered nanorobot for cancer therapy.

Multifunctional cell therapeutics with plasmonic nanobubbles

NASA Astrophysics Data System (ADS)

Lukianova-Hleb, Ekaterina Y.; Kashinath, Shruti; Lapotko, Dmitri O.

2012-03-01

We report our new discovery of the nanophenomenon called plasmonic nanobubbles to devise faster, safer and more accurate ways of manipulating the components of human tissue grafts. The reported work facilitates future cell and gene therapies by allowing specific cell subsets to be positively or negatively selected for culture, genetic engineering or elimination. The technology will have application for a wide range of human tissues that can be used to treat a multiplicity of human diseases.

Emerging Perspectives in Scaffold for Tissue Engineering in Oral Surgery

PubMed Central

Presta, Rossella

2017-01-01

Bone regeneration is currently one of the most important and challenging tissue engineering approaches in regenerative medicine. Bone regeneration is a promising approach in dentistry and is considered an ideal clinical strategy in treating diseases, injuries, and defects of the maxillofacial region. Advances in tissue engineering have resulted in the development of innovative scaffold designs, complemented by the progress made in cell-based therapies. In vitro bone regeneration can be achieved by the combination of stem cells, scaffolds, and bioactive factors. The biomimetic approach to create an ideal bone substitute provides strategies for developing combined scaffolds composed of adult stem cells with mesenchymal phenotype and different organic biomaterials (such as collagen and hyaluronic acid derivatives) or inorganic biomaterials such as manufactured polymers (polyglycolic acid (PGA), polylactic acid (PLA), and polycaprolactone). This review focuses on different biomaterials currently used in dentistry as scaffolds for bone regeneration in treating bone defects or in surgical techniques, such as sinus lift, horizontal and vertical bone grafts, or socket preservation. Our review would be of particular interest to medical and surgical researchers at the interface of cell biology, materials science, and tissue engineering, as well as industry-related manufacturers and researchers in healthcare, prosthetics, and 3D printing, too. PMID:28337223

Tissue Engineering Approaches in the Design of Healthy and Pathological In Vitro Tissue Models

PubMed Central

Caddeo, Silvia; Boffito, Monica; Sartori, Susanna

2017-01-01

In the tissue engineering (TE) paradigm, engineering and life sciences tools are combined to develop bioartificial substitutes for organs and tissues, which can in turn be applied in regenerative medicine, pharmaceutical, diagnostic, and basic research to elucidate fundamental aspects of cell functions in vivo or to identify mechanisms involved in aging processes and disease onset and progression. The complex three-dimensional (3D) microenvironment in which cells are organized in vivo allows the interaction between different cell types and between cells and the extracellular matrix, the composition of which varies as a function of the tissue, the degree of maturation, and health conditions. In this context, 3D in vitro models can more realistically reproduce a tissue or organ than two-dimensional (2D) models. Moreover, they can overcome the limitations of animal models and reduce the need for in vivo tests, according to the “3Rs” guiding principles for a more ethical research. The design of 3D engineered tissue models is currently in its development stage, showing high potential in overcoming the limitations of already available models. However, many issues are still opened, concerning the identification of the optimal scaffold-forming materials, cell source and biofabrication technology, and the best cell culture conditions (biochemical and physical cues) to finely replicate the native tissue and the surrounding environment. In the near future, 3D tissue-engineered models are expected to become useful tools in the preliminary testing and screening of drugs and therapies and in the investigation of the molecular mechanisms underpinning disease onset and progression. In this review, the application of TE principles to the design of in vitro 3D models will be surveyed, with a focus on the strengths and weaknesses of this emerging approach. In addition, a brief overview on the development of in vitro models of healthy and pathological bone, heart, pancreas, and liver will be presented. PMID:28798911

Tissue Engineering Approaches in the Design of Healthy and Pathological In Vitro Tissue Models.

PubMed

Caddeo, Silvia; Boffito, Monica; Sartori, Susanna

2017-01-01

In the tissue engineering (TE) paradigm, engineering and life sciences tools are combined to develop bioartificial substitutes for organs and tissues, which can in turn be applied in regenerative medicine, pharmaceutical, diagnostic, and basic research to elucidate fundamental aspects of cell functions in vivo or to identify mechanisms involved in aging processes and disease onset and progression. The complex three-dimensional (3D) microenvironment in which cells are organized in vivo allows the interaction between different cell types and between cells and the extracellular matrix, the composition of which varies as a function of the tissue, the degree of maturation, and health conditions. In this context, 3D in vitro models can more realistically reproduce a tissue or organ than two-dimensional (2D) models. Moreover, they can overcome the limitations of animal models and reduce the need for in vivo tests, according to the "3Rs" guiding principles for a more ethical research. The design of 3D engineered tissue models is currently in its development stage, showing high potential in overcoming the limitations of already available models. However, many issues are still opened, concerning the identification of the optimal scaffold-forming materials, cell source and biofabrication technology, and the best cell culture conditions (biochemical and physical cues) to finely replicate the native tissue and the surrounding environment. In the near future, 3D tissue-engineered models are expected to become useful tools in the preliminary testing and screening of drugs and therapies and in the investigation of the molecular mechanisms underpinning disease onset and progression. In this review, the application of TE principles to the design of in vitro 3D models will be surveyed, with a focus on the strengths and weaknesses of this emerging approach. In addition, a brief overview on the development of in vitro models of healthy and pathological bone, heart, pancreas, and liver will be presented.

Regenerative Medicine for Periodontal and Peri-implant Diseases

PubMed Central

Larsson, L.; Decker, A.M.; Nibali, L.; Pilipchuk, S.P.; Berglundh, T.; Giannobile, W.V.

2015-01-01

The balance between bone resorption and bone formation is vital for maintenance and regeneration of alveolar bone and supporting structures around teeth and dental implants. Tissue regeneration in the oral cavity is regulated by multiple cell types, signaling mechanisms, and matrix interactions. A goal for periodontal tissue engineering/regenerative medicine is to restore oral soft and hard tissues through cell, scaffold, and/or signaling approaches to functional and aesthetic oral tissues. Bony defects in the oral cavity can vary significantly, ranging from smaller intrabony lesions resulting from periodontal or peri-implant diseases to large osseous defects that extend through the jaws as a result of trauma, tumor resection, or congenital defects. The disparity in size and location of these alveolar defects is compounded further by patient-specific and environmental factors that contribute to the challenges in periodontal regeneration, peri-implant tissue regeneration, and alveolar ridge reconstruction. Efforts have been made over the last few decades to produce reliable and predictable methods to stimulate bone regeneration in alveolar bone defects. Tissue engineering/regenerative medicine provide new avenues to enhance tissue regeneration by introducing bioactive models or constructing patient-specific substitutes. This review presents an overview of therapies (e.g., protein, gene, and cell based) and biomaterials (e.g., resorbable, nonresorbable, and 3-dimensionally printed) used for alveolar bone engineering around teeth and implants and for implant site development, with emphasis on most recent findings and future directions. PMID:26608580

Concise review: carbon nanotechnology: perspectives in stem cell research.

PubMed

Pryzhkova, Marina V

2013-05-01

Carbon nanotechnology has developed rapidly during the last decade, and carbon allotropes, especially graphene and carbon nanotubes, have already found a wide variety of applications in industry, high-tech fields, biomedicine, and basic science. Electroconductive nanomaterials have attracted great attention from tissue engineers in the design of remotely controlled cell-substrate interfaces. Carbon nanoconstructs are also under extensive investigation by clinical scientists as potential agents in anticancer therapies. Despite the recent progress in human pluripotent stem cell research, only a few attempts to use carbon nanotechnology in the stem cell field have been reported. However, acquired experience with and knowledge of carbon nanomaterials may be efficiently used in the development of future personalized medicine and in tissue engineering.

New cell engineering approaches for cartilage regenerative medicine.

PubMed

Cucchiarini, Magali

2017-01-01

Articular cartilage injuries have an inadequate aptitude to reproduce the original structure and functions of this highly specialized tissue. As most of the currently available options also do not lead to the restoration of the original hyaline cartilage, novel treatments are critically needed to address this global problems in the clinics. Gene therapy combined with tissue engineering approaches offers effective tools capable of enhancing cartilage repair experimentally, especially those based on the controlled delivery of the highly effective, clinically adapted recombinant adeno-associated viral (rAAV) vectors. This work presents an overview of the most recent evidence showing the benefits of using rAAV vectors and biocompatible materials for the elaboration of adapted treatments against cartilage injuries.

Wireless Passive Stimulation of Engineered Cardiac Tissues.

PubMed

Liu, Shiyi; Navaei, Ali; Meng, Xueling; Nikkhah, Mehdi; Chae, Junseok

2017-07-28

We present a battery-free radio frequency (RF) microwave activated wireless stimulator, 25 × 42 × 1.6 mm 3 on a flexible substrate, featuring high current delivery, up to 60 mA, to stimulate engineered cardiac tissues. An external antenna shines 2.4 GHz microwave, which is modulated by an inverted pulse to directly control the stimulating waveform, to the wireless passive stimulator. The stimulator is equipped with an on-board antenna, multistage diode multipliers, and a control transistor. Rat cardiomyocytes, seeded on electrically conductive gelatin-based hydrogels, demonstrate synchronous contractions and Ca 2+ transients immediately upon stimulation. Notably, the stimulator output voltage and current profiles match the tissue contraction frequency within 0.5-2 Hz. Overall, our results indicate the promising potential of the proposed wireless passive stimulator for cardiac stimulation and therapy by induction of precisely controlled and synchronous contractions.

Platelet-rich plasma, an adjuvant biological therapy to assist peripheral nerve repair

PubMed Central

Sánchez, Mikel; Garate, Ane; Delgado, Diego; Padilla, Sabino

2017-01-01

Therapies such as direct tension-free microsurgical repair or transplantation of a nerve autograft, are nowadays used to treat traumatic peripheral nerve injuries (PNI), focused on the enhancement of the intrinsic regenerative potential of injured axons. However, these therapies fail to recreate the suitable cellular and molecular microenvironment of peripheral nerve repair and in some cases, the functional recovery of nerve injuries is incomplete. Thus, new biomedical engineering strategies based on tissue engineering approaches through molecular intervention and scaffolding offer promising outcomes on the field. In this sense, evidence is accumulating in both, preclinical and clinical settings, indicating that platelet-rich plasma products, and fibrin scaffold obtained from this technology, hold an important therapeutic potential as a neuroprotective, neurogenic and neuroinflammatory therapeutic modulator system, as well as enhancing the sensory and motor functional nerve muscle unit recovery. PMID:28250739

Cell and tissue engineering and clinical applications: an overview.

PubMed

Stoltz, J F; Bensoussan, D; Decot, V; Ciree, A; Netter, P; Gillet, P

2006-01-01

Most human tissues do not regenerate spontaneously; this is why cell therapies and tissue engineering are promising alternatives. The principle is simple: cells are collected in a patient and introduced in the damaged tissue or in a tridimentional porous support and harvested in a bioreactor in which the physico-chemical and mechanical parameters are controlled. Once the tissues (or the cells) are mature they may be implanted. In parallel, the development of biotherapies with stem cells is a field of research in turmoil given the hopes for clinical applications that it brings up. Embryonic stem cells are potentially more interesting since they are totipotent, but they can only be obtained at the very early stages of the embryo. The potential of adult stem cells is limited but isolating them induces no ethical problem and it has been known for more than 40 years that bone marrow does possess the regenerating functions of blood cells. Finally, the properties of foetal stem cells (blood cells from the umbilical cord) are forerunners of the haematopoietic system but the ability of these cells to participate to the formation of other tissues is more problematic. Another field for therapeutic research is that of dendritic cells, antigen presenting cells. Their efficiency in cell therapy relies on the initiation of specific immune responses. They represent a promising tool in the development of a protective immune response against antigens which the host is usually unable to generate an efficient response (melanomas, breast against cancer, prostate cancer, ..). Finally, gene therapy, has been nourishing high hopes but few clinical applications can be envisaged in the short term, although potential applications are multiple (haemophilia, myopathies, ..). A large number of clinical areas stand as candidates for clinical applications: leukaemia and cancers, cardiac insufficiency and vascular diseases, cartilage and bone repair, ligaments and tendons, liver diseases, ophthalmology, diabetes, neurological diseases (Parkinson, Huntington disease, ..), .. Various aspects of this new regenerative therapeutic medicine are developed in this work.

Naturally Engineered Maturation of Cardiomyocytes

PubMed Central

Scuderi, Gaetano J.; Butcher, Jonathan

2017-01-01

Ischemic heart disease remains one of the most prominent causes of mortalities worldwide with heart transplantation being the gold-standard treatment option. However, due to the major limitations associated with heart transplants, such as an inadequate supply and heart rejection, there remains a significant clinical need for a viable cardiac regenerative therapy to restore native myocardial function. Over the course of the previous several decades, researchers have made prominent advances in the field of cardiac regeneration with the creation of in vitro human pluripotent stem cell-derived cardiomyocyte tissue engineered constructs. However, these engineered constructs exhibit a functionally immature, disorganized, fetal-like phenotype that is not equivalent physiologically to native adult cardiac tissue. Due to this major limitation, many recent studies have investigated approaches to improve pluripotent stem cell-derived cardiomyocyte maturation to close this large functionality gap between engineered and native cardiac tissue. This review integrates the natural developmental mechanisms of cardiomyocyte structural and functional maturation. The variety of ways researchers have attempted to improve cardiomyocyte maturation in vitro by mimicking natural development, known as natural engineering, is readily discussed. The main focus of this review involves the synergistic role of electrical and mechanical stimulation, extracellular matrix interactions, and non-cardiomyocyte interactions in facilitating cardiomyocyte maturation. Overall, even with these current natural engineering approaches, pluripotent stem cell-derived cardiomyocytes within three-dimensional engineered heart tissue still remain mostly within the early to late fetal stages of cardiomyocyte maturity. Therefore, although the end goal is to achieve adult phenotypic maturity, more emphasis must be placed on elucidating how the in vivo fetal microenvironment drives cardiomyocyte maturation. This information can then be utilized to develop natural engineering approaches that can emulate this fetal microenvironment and thus make prominent progress in pluripotent stem cell-derived maturity toward a more clinically relevant model for cardiac regeneration. PMID:28529939

Dental and Nondental Stem Cell Based Regeneration of the Craniofacial Region: A Tissue Based Approach

PubMed Central

Hughes, Declan; Song, Bing

2016-01-01

Craniofacial reconstruction may be a necessary treatment for those who have been affected by trauma, disease, or pathological developmental conditions. The use of stem cell therapy and tissue engineering shows massive potential as a future treatment modality. Currently in the literature, there is a wide variety of published experimental studies utilising the different stem cell types available and the plethora of available scaffold materials. This review investigates different stem cell sources and their unique characteristics to suggest an ideal cell source for regeneration of individual craniofacial tissues. At present, understanding and clinical applications of stem cell therapy remain in their infancy with numerous challenges to overcome. In spite of this, the field displays immense capacity and will no doubt be utilised in future clinical treatments of craniofacial regeneration. PMID:27143979

Modeling the lung: Design and development of tissue engineered macro- and micro-physiologic lung models for research use.

PubMed

Nichols, Joan E; Niles, Jean A; Vega, Stephanie P; Argueta, Lissenya B; Eastaway, Adriene; Cortiella, Joaquin

2014-09-01

Respiratory tract specific cell populations, or tissue engineered in vitro grown human lung, have the potential to be used as research tools to mimic physiology, toxicology, pathology, as well as infectious diseases responses of cells or tissues. Studies related to respiratory tract pathogenesis or drug toxicity testing in the past made use of basic systems where single cell populations were exposed to test agents followed by evaluations of simple cellular responses. Although these simple single-cell-type systems provided good basic information related to cellular responses, much more can be learned from cells grown in fabricated microenvironments which mimic in vivo conditions in specialized microfabricated chambers or by human tissue engineered three-dimensional (3D) models which allow for more natural interactions between cells. Recent advances in microengineering technology, microfluidics, and tissue engineering have provided a new approach to the development of 2D and 3D cell culture models which enable production of more robust human in vitro respiratory tract models. Complex models containing multiple cell phenotypes also provide a more reasonable approximation of what occurs in vivo without the confounding elements in the dynamic in vivo environment. The goal of engineering good 3D human models is the formation of physiologically functional respiratory tissue surrogates which can be used as pathogenesis models or in the case of 2D screening systems for drug therapy evaluation as well as human toxicity testing. We hope that this manuscript will serve as a guide for development of future respiratory tract model systems as well as a review of conventional models. © 2014 by the Society for Experimental Biology and Medicine.

Developing a pro-regenerative biomaterial scaffold microenvironment requires T helper 2 cells.

PubMed

Sadtler, Kaitlyn; Estrellas, Kenneth; Allen, Brian W; Wolf, Matthew T; Fan, Hongni; Tam, Ada J; Patel, Chirag H; Luber, Brandon S; Wang, Hao; Wagner, Kathryn R; Powell, Jonathan D; Housseau, Franck; Pardoll, Drew M; Elisseeff, Jennifer H

2016-04-15

Immune-mediated tissue regeneration driven by a biomaterial scaffold is emerging as an innovative regenerative strategy to repair damaged tissues. We investigated how biomaterial scaffolds shape the immune microenvironment in traumatic muscle wounds to improve tissue regeneration. The scaffolds induced a pro-regenerative response, characterized by an mTOR/Rictor-dependent T helper 2 pathway that guides interleukin-4-dependent macrophage polarization, which is critical for functional muscle recovery. Manipulating the adaptive immune system using biomaterials engineering may support the development of therapies that promote both systemic and local pro-regenerative immune responses, ultimately stimulating tissue repair. Copyright © 2016, American Association for the Advancement of Science.

Developing a pro-regenerative biomaterial scaffold microenvironment requires T helper 2 cells

PubMed Central

Sadtler, Kaitlyn; Estrellas, Kenneth; Allen, Brian W.; Wolf, Matthew T.; Fan, Hongni; Tam, Ada J.; Patel, Chirag H.; Luber, Brandon S.; Wang, Hao; Wagner, Kathryn R.; Powell, Jonathan D.; Housseau, Franck; Pardoll, Drew M.

2016-01-01

Immune-mediated tissue regeneration driven by a biomaterial scaffold is emerging as an innovative regenerative strategy to repair damaged tissues. We investigated how biomaterial scaffolds shape the immune microenvironment in traumatic muscle wounds to improve tissue regeneration. The scaffolds induced a pro-regenerative response, characterized by an mTOR/Rictor-dependent T helper 2 pathway that guides interleukin-4–dependent macrophage polarization, which is critical for functional muscle recovery. Manipulating the adaptive immune system using biomaterials engineering may support the development of therapies that promote both systemic and local pro-regenerative immune responses, ultimately stimulating tissue repair. PMID:27081073

Engineering Bi-Layer Nanofibrous Conduits for Peripheral Nerve Regeneration

PubMed Central

Zhu, Yiqian; Wang, Aijun; Patel, Shyam; Kurpinski, Kyle; Diao, Edward; Bao, Xuan; Kwong, George; Young, William L.

2011-01-01

Trauma injuries often cause peripheral nerve damage and disability. A goal in neural tissue engineering is to develop synthetic nerve conduits for peripheral nerve regeneration having therapeutic efficacy comparable to that of autografts. Nanofibrous conduits with aligned nanofibers have been shown to promote nerve regeneration, but current fabrication methods rely on rolling a fibrous sheet into the shape of a conduit, which results in a graft with inconsistent size and a discontinuous joint or seam. In addition, the long-term effects of nanofibrous nerve conduits, in comparison with autografts, are still unknown. Here we developed a novel one-step electrospinning process and, for the first time, fabricated a seamless bi-layer nanofibrous nerve conduit: the luminal layer having longitudinally aligned nanofibers to promote nerve regeneration, and the outer layer having randomly organized nanofibers for mechanical support. Long-term in vivo studies demonstrated that bi-layer aligned nanofibrous nerve conduits were superior to random nanofibrous conduits and had comparable therapeutic effects to autografts for nerve regeneration. In summary, we showed that the engineered nanostructure had a significant impact on neural tissue regeneration in situ. The results from this study will also lead to the scalable fabrication of engineered nanofibrous nerve conduits with designed nanostructure. This technology platform can be combined with drug delivery and cell therapies for tissue engineering. PMID:21501089

Colloidal gas aphron foams: A novel approach to a hydrogel based tissue engineered myocardial patch

NASA Astrophysics Data System (ADS)

Johnson, Elizabeth Edna

Cardiovascular disease currently affects an estimated 58 million Americans and is the leading cause of death in the US. Over 2.3 million Americans are currently living with heart failure a leading cause of which is acute myocardial infarction, during which a part of the heart muscle is damaged beyond repair. There is a great need to develop treatments for damaged heart tissue. One potential therapy involves replacement of nonfunctioning scar tissue with a patch of healthy, functioning tissue. A tissue engineered cardiac patch would be ideal for such an application. Tissue engineering techniques require the use of porous scaffolds, which serve as a 3-D template for initial cell attachment and grow-th leading to tissue formation. The scaffold must also have mechanical properties closely matching those of the tissues at the site of implantation. Our research presents a new approach to meet these design requirements. A unique interaction between poly(vinyl alcohol) and amino acids has been discovered by our lab, resulting in the production of novel gels. These unique synthetic hydrogels along with one natural hydrogel, alginate (derived from brown seaweed), have been coupled with a new approach to tissue scaffold fabrication using solid colloidal gas aphrons (CGAs). CGAs are colloidal foams containing uniform bubbles with diameters on the order of micrometers. Upon solidification the GCAs form a porous, 3-D network suitable for a tissue scaffold. The project encompasses four specific aims: (I) characterize hydrogel formation mechanism, (II) use colloidal gas aphrons to produce hydrogel scaffolds, (III) chemically and physically characterize scaffold materials and (IV) optimize and evaluate scaffold biocompatibility.

Biomechanical regulation of in vitro cardiogenesis for tissue-engineered heart repair.

PubMed

Zimmermann, Wolfram-Hubertus

2013-01-01

The heart is a continuously pumping organ with an average lifespan of eight decades. It develops from the onset of embryonic cardiogenesis under biomechanical load, performs optimally within a defined range of hemodynamic load, and fails if acutely or chronically overloaded. Unloading of the heart leads to defective cardiogenesis in utero, but can also lead to a desired therapeutic outcome (for example, in patients with heart failure under left ventricular assist device therapy). In light of the well-documented relevance of mechanical loading for cardiac physiology and pathology, it is plausible that tissue engineers have integrated mechanical stimulation regimens into protocols for heart muscle construction. To achieve optimal results, physiological principles of beat-to-beat myocardial loading and unloading should be simulated. In addition, heart muscle engineering, in particular if based on pluripotent stem cell-derived cardiomyocytes, may benefit from staggered tonic loading protocols to simulate viscoelastic properties of the prenatal and postnatal myocardial stroma. This review will provide an overview of heart muscle mechanics, summarize observations on the role of mechanical loading for heart development and postnatal performance, and discuss how physiological loading regimens can be exploited to advance myocardial tissue engineering towards a therapeutic application.

Biomechanical regulation of in vitro cardiogenesis for tissue-engineered heart repair

PubMed Central

2013-01-01

The heart is a continuously pumping organ with an average lifespan of eight decades. It develops from the onset of embryonic cardiogenesis under biomechanical load, performs optimally within a defined range of hemodynamic load, and fails if acutely or chronically overloaded. Unloading of the heart leads to defective cardiogenesis in utero, but can also lead to a desired therapeutic outcome (for example, in patients with heart failure under left ventricular assist device therapy). In light of the well-documented relevance of mechanical loading for cardiac physiology and pathology, it is plausible that tissue engineers have integrated mechanical stimulation regimens into protocols for heart muscle construction. To achieve optimal results, physiological principles of beat-to-beat myocardial loading and unloading should be simulated. In addition, heart muscle engineering, in particular if based on pluripotent stem cell-derived cardiomyocytes, may benefit from staggered tonic loading protocols to simulate viscoelastic properties of the prenatal and postnatal myocardial stroma. This review will provide an overview of heart muscle mechanics, summarize observations on the role of mechanical loading for heart development and postnatal performance, and discuss how physiological loading regimens can be exploited to advance myocardial tissue engineering towards a therapeutic application. PMID:24229468

Rheological properties of a biological thermo-responsive hydrogel prepared from vegetable oil

USDA-ARS?s Scientific Manuscript database

Hydrogel is a colloidal gel in which water is the dispersion medium. The unique properties of hydrogels make this kind of materials have many utilization potentials, such as drug delivery, gene therapy, wound care products, breast implant materials, cosmetic products, and tissue engineering. Hydroge...

Microencapsulation of Drugs: New Cancer Therapies and Improved Drug Delivery Derived from Micro Gravity Research

NASA Technical Reports Server (NTRS)

Morrison, Dennis R.; Haddad, Ruwaida S.

2003-01-01

Experiments on the ISS include encapsulation of several different anti-cancer drugs, magnetic triggering particles, and encapsulation of genetically engineered DNA. Eight experiments, using the MEPS-II apparatus, were conducted to study the limitations of the fluid shear and g-dependent forces. These studies included: 1) formation of anti-tumor microcapsules containing drugs for "Chemoembolization" of vascularized tumors, 2) formation of microcapsules containing a photo-activated drug which can be used for Photo Dynamic Therapy of solid tumors by activation with near infrared light (630 nm), 3) coencapsulation of magnetic trigger particles and anti-tumor drugs, and 4) encapsulation of plasmid DNA. The Microencapsulation Electrostatic Processing System (MEPS-II) is an automated apparatus modified for use in the ISS Express Rack. The process brings together two immiscible liquids, restricting fluid shear to permitting surface tension forces to predominate at the interface of the fluids. Microcapsules were recovered from all 8 experiments and are currently being analyzed for size distribution and drug content. Six NASA Patents have issued from the space research and several more are pending. The preliminary results from the Increment 5 - UF-2 experiments have provided new insight into the best formulations and conditions required to produce microcapsules of different drugs, esp. special capsules containing diagnostic imaging materials and triggered release particles. Co-encapsulation of multiple drugs and Photodynamic Therapy (PDT) drugs has enabled new engineering strategies for production of microcapsules on Earth designed for direct delivery into cancer tissues. Other microcapsules have now been made for treatment of deep tissue infections, clotting disorders, and to provide delivery of genetic engineered materials for potential gene therapy approaches. The MEPS-II apparatus remains in the ISS awaiting microencapsulation experiments to be conducted in micro-g, and returned to Earth for analysis.

Genetic Engineering of Mesenchymal Stem Cells for Regenerative Medicine.

PubMed

Nowakowski, Adam; Walczak, Piotr; Janowski, Miroslaw; Lukomska, Barbara

2015-10-01

Mesenchymal stem cells (MSCs), which can be obtained from various organs and easily propagated in vitro, are one of the most extensively used types of stem cells and have been shown to be efficacious in a broad set of diseases. The unique and highly desirable properties of MSCs include high migratory capacities toward injured areas, immunomodulatory features, and the natural ability to differentiate into connective tissue phenotypes. These phenotypes include bone and cartilage, and these properties predispose MSCs to be therapeutically useful. In addition, MSCs elicit their therapeutic effects by paracrine actions, in which the metabolism of target tissues is modulated. Genetic engineering methods can greatly amplify these properties and broaden the therapeutic capabilities of MSCs, including transdifferentiation toward diverse cell lineages. However, cell engineering can also affect safety and increase the cost of therapy based on MSCs; thus, the advantages and disadvantages of these procedures should be discussed. In this review, the latest applications of genetic engineering methods for MSCs with regenerative medicine purposes are presented.

Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering

PubMed Central

Ogueri, Kenneth S.; Escobar Ivirico, Jorge L.; Nair, Lakshmi S.; Allcock, Harry R.; Laurencin, Cato T.

2017-01-01

The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Lay Summary Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of this new approach which involves the regeneration of complex tissues and biological systems such as a knee or a whole limb. While a number of excellent advanced biomaterials have been developed, the choice of biomaterials, however, has increased over the past years to include polymers that can be designed with a range of mechanical properties, degradation rates, and chemical functionality. The polyphosphazenes are one good example. Their chemical versatility and hydrogen bonding capability encourages blending with other biologically relevant polymers. The further development of Polyphosphazene-based blends will present a wide spectrum of advanced biomaterials that can be used as scaffolds for regenerative engineering and as well as other biomedical applications. PMID:28596987

Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering.

PubMed

Ogueri, Kenneth S; Escobar Ivirico, Jorge L; Nair, Lakshmi S; Allcock, Harry R; Laurencin, Cato T

2017-03-01

The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of this new approach which involves the regeneration of complex tissues and biological systems such as a knee or a whole limb. While a number of excellent advanced biomaterials have been developed, the choice of biomaterials, however, has increased over the past years to include polymers that can be designed with a range of mechanical properties, degradation rates, and chemical functionality. The polyphosphazenes are one good example. Their chemical versatility and hydrogen bonding capability encourages blending with other biologically relevant polymers. The further development of Polyphosphazene-based blends will present a wide spectrum of advanced biomaterials that can be used as scaffolds for regenerative engineering and as well as other biomedical applications.

Cell-laden hydrogels for osteochondral and cartilage tissue engineering.

PubMed

Yang, Jingzhou; Zhang, Yu Shrike; Yue, Kan; Khademhosseini, Ali

2017-07-15

Despite tremendous advances in the field of regenerative medicine, it still remains challenging to repair the osteochondral interface and full-thickness articular cartilage defects. This inefficiency largely originates from the lack of appropriate tissue-engineered artificial matrices that can replace the damaged regions and promote tissue regeneration. Hydrogels are emerging as a promising class of biomaterials for both soft and hard tissue regeneration. Many critical properties of hydrogels, such as mechanical stiffness, elasticity, water content, bioactivity, and degradation, can be rationally designed and conveniently tuned by proper selection of the material and chemistry. Particularly, advances in the development of cell-laden hydrogels have opened up new possibilities for cell therapy. In this article, we describe the problems encountered in this field and review recent progress in designing cell-hydrogel hybrid constructs for promoting the reestablishment of osteochondral/cartilage tissues. Our focus centers on the effects of hydrogel type, cell type, and growth factor delivery on achieving efficient chondrogenesis and osteogenesis. We give our perspective on developing next-generation matrices with improved physical and biological properties for osteochondral/cartilage tissue engineering. We also highlight recent advances in biomanufacturing technologies (e.g. molding, bioprinting, and assembly) for fabrication of hydrogel-based osteochondral and cartilage constructs with complex compositions and microarchitectures to mimic their native counterparts. Despite tremendous advances in the field of regenerative medicine, it still remains challenging to repair the osteochondral interface and full-thickness articular cartilage defects. This inefficiency largely originates from the lack of appropriate tissue-engineered biomaterials that replace the damaged regions and promote tissue regeneration. Cell-laden hydrogel systems have emerged as a promising tissue-engineering platform to address this issue. In this article, we describe the fundamental problems encountered in this field and review recent progress in designing cell-hydrogel constructs for promoting the reestablishment of osteochondral/cartilage tissues. Our focus centers on the effects of hydrogel composition, cell type, and growth factor delivery on achieving efficient chondrogenesis and osteogenesis. We give our perspective on developing next-generation hydrogel/inorganic particle/stem cell hybrid composites with improved physical and biological properties for osteochondral/cartilage tissue engineering. We also highlight recent advances in biomanufacturing and bioengineering technologies (e.g. 3D bioprinting) for fabrication of hydrogel-based osteochondral and cartilage constructs. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Juvenile Swine Surgical Alveolar Cleft Model to Test Novel Autologous Stem Cell Therapies

PubMed Central

Caballero, Montserrat; Morse, Justin C.; Halevi, Alexandra E.; Emodi, Omri; Pharaon, Michael R.; Wood, Jeyhan S.

2015-01-01

Reconstruction of craniofacial congenital bone defects has historically relied on autologous bone grafts. Engineered bone using mesenchymal stem cells from the umbilical cord on electrospun nanomicrofiber scaffolds offers an alternative to current treatments. This preclinical study presents the development of a juvenile swine model with a surgically created maxillary cleft defect for future testing of tissue-engineered implants for bone generation. Five-week-old pigs (n=6) underwent surgically created maxillary (alveolar) defects to determine critical-sized defect and the quality of treatment outcomes with rib, iliac crest cancellous bone, and tissue-engineered scaffolds. Pigs were sacrificed at 1 month. Computed tomography scans were obtained at days 0 and 30, at the time of euthanasia. Histological evaluation was performed on newly formed bone within the surgical defect. A 1 cm surgically created defect healed with no treatment, the 2 cm defect did not heal. A subsequently created 1.7 cm defect, physiologically similar to a congenitally occurring alveolar cleft in humans, from the central incisor to the canine, similarly did not heal. Rib graft treatment did not incorporate into adjacent normal bone; cancellous bone and the tissue-engineered graft healed the critical-sized defect. This work establishes a juvenile swine alveolar cleft model with critical-sized defect approaching 1.7 cm. Both cancellous bone and tissue engineered graft generated bridging bone formation in the surgically created alveolar cleft defect. PMID:25837453

Tracking of adipose tissue-derived progenitor cells using two magnetic nanoparticle types

NASA Astrophysics Data System (ADS)

Kasten, Annika; Siegmund, Birte J.; Grüttner, Cordula; Kühn, Jens-Peter; Frerich, Bernhard

2015-04-01

Magnetic resonance imaging (MRI) is to be considered as an emerging detection technique for cell tracking experiments to evaluate the fate of transplanted progenitor cells and develop successful cell therapies for tissue engineering. Adipose tissue engineering using adipose tissue-derived progenitor cells has been advocated for the cure of soft tissue defects or for persistent soft tissue augmentation. Adipose tissue-derived progenitor cells were differentiated into the adipogenic lineage and labeled with two different types of magnetic iron oxide nanoparticles in varying concentrations which resulted in a concentration-dependent reduction of gene expression of adipogenic differentiation markers, adiponectin and fatty acid-binding protein 4 (FABP4), whereas the metabolic activity was not altered. As a result, only low nanoparticle concentrations for labeling were used for in vivo experiments. Cells were seeded onto collagen scaffolds and subcutaneously implanted into severe combined immunodeficient (SCID) mice. At 24 h as well as 28 days after implantation, MRI analyses were performed visualizing nanoparticle-labeled cells using T2-weighted sequences. The quantification of absolute volume of the scaffolds revealed a decrease of volume over time in all experimental groups. The distribution of nanoparticle-labeled cells within the scaffolds varied likewise over time.

Driving gene-engineered T cell immunotherapy of cancer

PubMed Central

Johnson, Laura A; June, Carl H

2017-01-01

Chimeric antigen receptor (CAR) gene-engineered T cell therapy holds the potential to make a meaningful difference in the lives of patients with terminal cancers. For decades, cancer therapy was based on biophysical parameters, with surgical resection to debulk, followed by radiation and chemotherapy to target the rapidly growing tumor cells, while mostly sparing quiescent normal tissues. One breakthrough occurred with allogeneic bone-marrow transplant for patients with leukemia, which provided a sometimes curative therapy. The field of adoptive cell therapy for solid tumors was established with the discovery that tumor-infiltrating lymphocytes could be expanded and used to treat and even cure patients with metastatic melanoma. Tumor-specific T-cell receptors (TCRs) were identified and engineered into patient peripheral blood lymphocytes, which were also found to treat tumors. However, these were limited by patient HLA-restriction. Close behind came generation of CAR, combining the exquisite recognition of an antibody with the effector function of a T cell. The advent of CD19-targeted CARs for treating patients with multiple forms of advanced B-cell malignancies met with great success, with up to 95% response rates. Applying CAR treatment to solid tumors, however, has just begun, but already certain factors have been made clear: the tumor target is of utmost importance for clinicians to do no harm; and solid tumors respond differently to CAR therapy compared with hematologic ones. Here we review the state of clinical gene-engineered T cell immunotherapy, its successes, challenges, and future. PMID:28025979

Bisphosphonate-Based Strategies for Bone Tissue Engineering and Orthopedic Implants

PubMed Central

Cattalini, Juan Pablo; Boccaccini, Aldo R.; Lucangioli, Silvia

2012-01-01

Bisphosphonates (BPs) are a group of well-established drugs that are applied in the development of metabolic bone disorder-related therapies. There is increasing interest also in the application of BPs in the context of bone tissue engineering, which is the topic of this review, in which an extensive overview of published studies on the development and applications of BPs-based strategies for bone regeneration is provided with special focus on the rationale for the use of different BPs in three-dimensional (3D) bone tissue scaffolds. The different alternatives that are investigated to address the delivery and sustained release of these therapeutic drugs in the nearby tissues are comprehensively discussed, and the most significant published approaches on bisphosphonate-conjugated drugs in multifunctional 3D scaffolds as well as the role of BPs within coatings for the improved fixation of orthopedic implants are presented and critically evaluated. Finally, the authors' views regarding the remaining challenges in the fields and directions for future research efforts are highlighted. PMID:22440082

Ebselen Preserves Tissue-Engineered Cell Sheets and their Stem Cells in Hypothermic Conditions

PubMed Central

Katori, Ryosuke; Hayashi, Ryuhei; Kobayashi, Yuki; Kobayashi, Eiji; Nishida, Kohji

2016-01-01

Clinical trials have been performed using autologous tissue-engineered epithelial cell sheets for corneal regenerative medicine. To improve stem cell-based therapy for convenient clinical practice, new techniques are required for preserving reconstructed tissues and their stem/progenitor cells until they are ready for use. In the present study, we screened potential preservative agents and developed a novel medium for preserving the cell sheets and their stem/progenitor cells; the effects were evaluated with a luciferase-based viability assay. Nrf2 activators, specifically ebselen, could maintain high ATP levels during preservation. Ebselen also showed a strong influence on maintenance of the viability, morphology, and stem cell function of the cell sheets preserved under hypothermia by protecting them from reactive oxygen species-induced damage. Furthermore, ebselen drastically improved the preservation performance of human cornea tissues and their stem cells. Therefore, ebselen shows good potential as a useful preservation agent in regenerative medicine as well as in cornea transplantation. PMID:27966584

Further insights into the characterization of equine adipose tissue-derived mesenchymal stem cells.

PubMed

Raabe, Oksana; Shell, Katja; Würtz, Antonia; Reich, Christine Maria; Wenisch, Sabine; Arnhold, Stefan

2011-08-01

Adipose tissue-derived stem cells (ADSCs) represent a promising subpopulation of adult stem cells for tissue engineering applications in veterinary medicine. In this study we focused on the morphological and molecular biological properties of the ADSCs. The expression of stem cell markers Oct4, Nanog and the surface markers CD90 and CD105 were detected using RT-PCR. ADSCs showed a proliferative potential and were capable of adipogenic and osteogenic differentiation. Expression of Alkaline phosphatase (AP), phosphoprotein (SPP1), Runx2 and osteocalcin (OC) mRNA were positive in osteogenic lineages and peroxisome proliferator activated receptor (Pparγ2) mRNA was positive in adipogenic lineages. ADSCs show stem cell and surface marker profiles and differentiation characteristics that are similar to but distinct from other adult stem cells, such as bone marrow-derived mesenchymal stem cells (BM-MSCs). The availability of an easily accessible and reproducible cell source may greatly facilitate the development of stem cell based tissue engineering and therapies for regenerative equine medicine.

Ebselen Preserves Tissue-Engineered Cell Sheets and their Stem Cells in Hypothermic Conditions.

PubMed

Katori, Ryosuke; Hayashi, Ryuhei; Kobayashi, Yuki; Kobayashi, Eiji; Nishida, Kohji

2016-12-14

Clinical trials have been performed using autologous tissue-engineered epithelial cell sheets for corneal regenerative medicine. To improve stem cell-based therapy for convenient clinical practice, new techniques are required for preserving reconstructed tissues and their stem/progenitor cells until they are ready for use. In the present study, we screened potential preservative agents and developed a novel medium for preserving the cell sheets and their stem/progenitor cells; the effects were evaluated with a luciferase-based viability assay. Nrf2 activators, specifically ebselen, could maintain high ATP levels during preservation. Ebselen also showed a strong influence on maintenance of the viability, morphology, and stem cell function of the cell sheets preserved under hypothermia by protecting them from reactive oxygen species-induced damage. Furthermore, ebselen drastically improved the preservation performance of human cornea tissues and their stem cells. Therefore, ebselen shows good potential as a useful preservation agent in regenerative medicine as well as in cornea transplantation.

Engineering the extracellular matrix for clinical applications: endoderm, mesoderm, and ectoderm.

PubMed

Williams, Miguel L; Bhatia, Sujata K

2014-03-01

Tissue engineering is rapidly progressing from a research-based discipline to clinical applications. Emerging technologies could be utilized to develop therapeutics for a wide range of diseases, but many are contingent on a cell scaffold that can produce proper tissue ultrastructure. The extracellular matrix, which a cell scaffold simulates, is not merely a foundation for tissue growth but a dynamic participant in cellular crosstalk and organ homeostasis. Cells change their growth rates, recruitment, and differentiation in response to the composition, modulus, and patterning of the substrate on which they reside. Cell scaffolds can regulate these factors through precision design, functionalization, and application. The ideal therapy would utilize highly specialized cell scaffolds to best mimic the tissue of interest. This paper discusses advantages and challenges of optimized cell scaffold design in the endoderm, mesoderm, and ectoderm for clinical applications in tracheal transplant, cardiac regeneration, and skin grafts, respectively. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Injectable Biodegradable Polyurethane Scaffolds with Release of Platelet-derived Growth Factor for Tissue Repair and Regeneration

PubMed Central

Hafeman, Andrea E.; Li, Bing; Yoshii, Toshitaka; Zienkiewicz, Katarzyna; Davidson, Jeffrey M.; Guelcher, Scott A.

2013-01-01

Purpose The purpose of this work was to investigate the effects of triisocyanate composition on the biological and mechanical properties of biodegradable, injectable polyurethane scaffolds for bone and soft tissue engineering. Methods Scaffolds were synthesized using reactive liquid molding techniques, and were characterized in vivo in a rat subcutaneous model. Porosity, dynamic mechanical properties, degradation rate, and release of growth factors were also measured. Results Polyurethane scaffolds were elastomers with tunable damping properties and degradation rates, and they supported cellular infiltration and generation of new tissue. The scaffolds showed a two-stage release profile of platelet-derived growth factor, characterized by a 75% burst release within the first 24 h and slower release thereafter. Conclusions Biodegradable polyurethanes synthesized from triisocyanates exhibited tunable and superior mechanical properties compared to materials synthesized from lysine diisocyanates. Due to their injectability, biocompatibility, tunable degradation, and potential for release of growth factors, these materials are potentially promising therapies for tissue engineering. PMID:18516665

Stem Cells Applications in Regenerative Medicine and Disease Therapeutics

PubMed Central

2016-01-01

Regenerative medicine, the most recent and emerging branch of medical science, deals with functional restoration of tissues or organs for the patient suffering from severe injuries or chronic disease. The spectacular progress in the field of stem cell research has laid the foundation for cell based therapies of disease which cannot be cured by conventional medicines. The indefinite self-renewal and potential to differentiate into other types of cells represent stem cells as frontiers of regenerative medicine. The transdifferentiating potential of stem cells varies with source and according to that regenerative applications also change. Advancements in gene editing and tissue engineering technology have endorsed the ex vivo remodelling of stem cells grown into 3D organoids and tissue structures for personalized applications. This review outlines the most recent advancement in transplantation and tissue engineering technologies of ESCs, TSPSCs, MSCs, UCSCs, BMSCs, and iPSCs in regenerative medicine. Additionally, this review also discusses stem cells regenerative application in wildlife conservation. PMID:27516776

Bioprinting for Neural Tissue Engineering.

PubMed

Knowlton, Stephanie; Anand, Shivesh; Shah, Twisha; Tasoglu, Savas

2018-01-01

Bioprinting is a method by which a cell-encapsulating bioink is patterned to create complex tissue architectures. Given the potential impact of this technology on neural research, we review the current state-of-the-art approaches for bioprinting neural tissues. While 2D neural cultures are ubiquitous for studying neural cells, 3D cultures can more accurately replicate the microenvironment of neural tissues. By bioprinting neuronal constructs, one can precisely control the microenvironment by specifically formulating the bioink for neural tissues, and by spatially patterning cell types and scaffold properties in three dimensions. We review a range of bioprinted neural tissue models and discuss how they can be used to observe how neurons behave, understand disease processes, develop new therapies and, ultimately, design replacement tissues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synergizing Engineering and Biology to Treat and Model Skeletal Muscle Injury and Disease

PubMed Central

Bursac, Nenad; Juhas, Mark; Rando, Thomas A.

2016-01-01

Although skeletal muscle is one of the most regenerative organs in our body, various genetic defects, alterations in extrinsic signaling, or substantial tissue damage can impair muscle function and the capacity for self-repair. The diversity and complexity of muscle disorders have attracted much interest from both cell biologists and, more recently, bioengineers, leading to concentrated efforts to better understand muscle pathology and develop more efficient therapies. This review describes the biological underpinnings of muscle development, repair, and disease, and discusses recent bioengineering efforts to design and control myomimetic environments, both to study muscle biology and function and to aid in the development of new drug, cell, and gene therapies for muscle disorders. The synergy between engineering-aided biological discovery and biology-inspired engineering solutions will be the path forward for translating laboratory results into clinical practice. PMID:26643021

Cell- and Gene-Based Therapeutic Strategies for Periodontal Regenerative Medicine

PubMed Central

Rios, Hector F.; Lin, Zhao; Oh, BiNa; Park, Chan Ho; Giannobile, William V.

2012-01-01

Inflammatory periodontal diseases are a leading cause of tooth loss and are linked to multiple systemic conditions, such as cardiovascular disease and stroke. Reconstruction of the support and function of affected tooth-supporting tissues represents an important therapeutic endpoint for periodontal regenerative medicine. An improved understanding of periodontal biology coupled with current advances in scaffolding matrices has introduced novel treatments that use cell and gene therapy to enhance periodontal tissue reconstruction and its biomechanical integration. Cell and gene delivery technologies have the potential to overcome limitations associated with existing periodontal therapies, and may provide a new direction in sustainable inflammation control and more predictable tissue regeneration of supporting alveolar bone, periodontal ligament, and cementum. This review provides clinicians with the current status of these early-stage and emerging cell- and gene-based therapeutics in periodontal regenerative medicine, and introduces their future application in clinical periodontal treatment. The paper concludes with prospects on the application of cell and gene tissue engineering technologies for reconstructive periodontology. PMID:21284553

Non-viral gene therapy for bone tissue engineering.

PubMed

Wegman, Fiona; Oner, F Cumhur; Dhert, Wouter J A; Alblas, Jacqueline

2013-01-01

The possibilities of using gene therapy for bone regeneration have been extensively investigated. Improvements in the design of new transfection agents, combining vectors and delivery/release systems to diminish cytotoxicity and increase transfection efficiencies have led to several successful in vitro, ex vivo and in vivo strategies. These include growth factor or short interfering ribonucleic acid (siRNA) delivery, or even enzyme replacement therapies, and have led to increased osteogenic differentiation and bone formation in vivo. These results provide optimism to consider use in humans with some of these gene-delivery strategies in the near future.

Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

PubMed

Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

2000-04-01

Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

Stem Cell Extracellular Vesicles: Extended Messages of Regeneration

PubMed Central

Riazifar, Milad; Pone, Egest J.; Lötvall, Jan; Zhao, Weian

2017-01-01

Stem cells are critical to maintaining steady-state organ homeostasis and regenerating injured tissues. Recent intriguing reports implicate extracellular vesicles (EVs) as carriers for the distribution of morphogens and growth and differentiation factors from tissue parenchymal cells to stem cells, and conversely, stem cell–derived EVs carrying certain proteins and nucleic acids can support healing of injured tissues. We describe approaches to make use of engineered EVs as technology platforms in therapeutics and diagnostics in the context of stem cells. For some regenerative therapies, natural and engineered EVs from stem cells may be superior to single-molecule drugs, biologics, whole cells, and synthetic liposome or nanoparticle formulations because of the ease of bioengineering with multiple factors while retaining superior biocompatibility and biostability and posing fewer risks for abnormal differentiation or neoplastic transformation. Finally, we provide an overview of current challenges and future directions of EVs as potential therapeutic alternatives to cells for clinical applications. PMID:27814025

Infused polymers for cell sheet release

NASA Astrophysics Data System (ADS)

Juthani, Nidhi; Howell, Caitlin; Ledoux, Haylea; Sotiri, Irini; Kelso, Susan; Kovalenko, Yevgen; Tajik, Amanda; Vu, Thy L.; Lin, Jennifer J.; Sutton, Amy; Aizenberg, Joanna

2016-05-01

Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering.

Infused polymers for cell sheet release

PubMed Central

Juthani, Nidhi; Howell, Caitlin; Ledoux, Haylea; Sotiri, Irini; Kelso, Susan; Kovalenko, Yevgen; Tajik, Amanda; Vu, Thy L.; Lin, Jennifer J.; Sutton, Amy; Aizenberg, Joanna

2016-01-01

Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering. PMID:27189419

Infused polymers for cell sheet release.

PubMed

Juthani, Nidhi; Howell, Caitlin; Ledoux, Haylea; Sotiri, Irini; Kelso, Susan; Kovalenko, Yevgen; Tajik, Amanda; Vu, Thy L; Lin, Jennifer J; Sutton, Amy; Aizenberg, Joanna

2016-05-18

Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering.

Pluripotency of Stem Cells from Human Exfoliated Deciduous Teeth for Tissue Engineering

PubMed Central

Rosa, Vinicius; Dubey, Nileshkumar; Islam, Intekhab; Min, Kyung-San; Nör, Jacques E.

2016-01-01

Stem cells from human exfoliated deciduous teeth (SHED) are highly proliferative pluripotent cells that can be retrieved from primary teeth. Although SHED are isolated from the dental pulp, their differentiation potential is not limited to odontoblasts only. In fact, SHED can differentiate into several cell types including neurons, osteoblasts, adipocytes, and endothelial cells. The high plasticity makes SHED an interesting stem cell model for research in several biomedical areas. This review will discuss key findings about the characterization and differentiation of SHED into odontoblasts, neurons, and hormone secreting cells (e.g., hepatocytes and islet-like cell aggregates). The outcomes of the studies presented here support the multipotency of SHED and their potential to be used for tissue engineering-based therapies. PMID:27313627

Concise Review: Carbon Nanotechnology: Perspectives in Stem Cell Research

PubMed Central

2013-01-01

Carbon nanotechnology has developed rapidly during the last decade, and carbon allotropes, especially graphene and carbon nanotubes, have already found a wide variety of applications in industry, high-tech fields, biomedicine, and basic science. Electroconductive nanomaterials have attracted great attention from tissue engineers in the design of remotely controlled cell-substrate interfaces. Carbon nanoconstructs are also under extensive investigation by clinical scientists as potential agents in anticancer therapies. Despite the recent progress in human pluripotent stem cell research, only a few attempts to use carbon nanotechnology in the stem cell field have been reported. However, acquired experience with and knowledge of carbon nanomaterials may be efficiently used in the development of future personalized medicine and in tissue engineering. PMID:23572053

Regenerative Medicine for Periodontal and Peri-implant Diseases.

PubMed

Larsson, L; Decker, A M; Nibali, L; Pilipchuk, S P; Berglundh, T; Giannobile, W V

2016-03-01

The balance between bone resorption and bone formation is vital for maintenance and regeneration of alveolar bone and supporting structures around teeth and dental implants. Tissue regeneration in the oral cavity is regulated by multiple cell types, signaling mechanisms, and matrix interactions. A goal for periodontal tissue engineering/regenerative medicine is to restore oral soft and hard tissues through cell, scaffold, and/or signaling approaches to functional and aesthetic oral tissues. Bony defects in the oral cavity can vary significantly, ranging from smaller intrabony lesions resulting from periodontal or peri-implant diseases to large osseous defects that extend through the jaws as a result of trauma, tumor resection, or congenital defects. The disparity in size and location of these alveolar defects is compounded further by patient-specific and environmental factors that contribute to the challenges in periodontal regeneration, peri-implant tissue regeneration, and alveolar ridge reconstruction. Efforts have been made over the last few decades to produce reliable and predictable methods to stimulate bone regeneration in alveolar bone defects. Tissue engineering/regenerative medicine provide new avenues to enhance tissue regeneration by introducing bioactive models or constructing patient-specific substitutes. This review presents an overview of therapies (e.g., protein, gene, and cell based) and biomaterials (e.g., resorbable, nonresorbable, and 3-dimensionally printed) used for alveolar bone engineering around teeth and implants and for implant site development, with emphasis on most recent findings and future directions. © International & American Associations for Dental Research 2015.

Predicting cell viability within tissue scaffolds under equiaxial strain: multi-scale finite element model of collagen-cardiomyocytes constructs.

PubMed

Elsaadany, Mostafa; Yan, Karen Chang; Yildirim-Ayan, Eda

2017-06-01

Successful tissue engineering and regenerative therapy necessitate having extensive knowledge about mechanical milieu in engineered tissues and the resident cells. In this study, we have merged two powerful analysis tools, namely finite element analysis and stochastic analysis, to understand the mechanical strain within the tissue scaffold and residing cells and to predict the cell viability upon applying mechanical strains. A continuum-based multi-length scale finite element model (FEM) was created to simulate the physiologically relevant equiaxial strain exposure on cell-embedded tissue scaffold and to calculate strain transferred to the tissue scaffold (macro-scale) and residing cells (micro-scale) upon various equiaxial strains. The data from FEM were used to predict cell viability under various equiaxial strain magnitudes using stochastic damage criterion analysis. The model validation was conducted through mechanically straining the cardiomyocyte-encapsulated collagen constructs using a custom-built mechanical loading platform (EQUicycler). FEM quantified the strain gradients over the radial and longitudinal direction of the scaffolds and the cells residing in different areas of interest. With the use of the experimental viability data, stochastic damage criterion, and the average cellular strains obtained from multi-length scale models, cellular viability was predicted and successfully validated. This methodology can provide a great tool to characterize the mechanical stimulation of bioreactors used in tissue engineering applications in providing quantification of mechanical strain and predicting cellular viability variations due to applied mechanical strain.

Generation and Assessment of Functional Biomaterial Scaffolds for Applications in Cardiovascular Tissue Engineering and Regenerative Medicine

PubMed Central

Hinderer, Svenja; Brauchle, Eva

2015-01-01

Current clinically applicable tissue and organ replacement therapies are limited in the field of cardiovascular regenerative medicine. The available options do not regenerate damaged tissues and organs, and, in the majority of the cases, show insufficient restoration of tissue function. To date, anticoagulant drug‐free heart valve replacements or growing valves for pediatric patients, hemocompatible and thrombus‐free vascular substitutes that are smaller than 6 mm, and stem cell‐recruiting delivery systems that induce myocardial regeneration are still only visions of researchers and medical professionals worldwide and far from being the standard of clinical treatment. The design of functional off‐the‐shelf biomaterials as well as automatable and up‐scalable biomaterial processing methods are the focus of current research endeavors and of great interest for fields of tissue engineering and regenerative medicine. Here, various approaches that aim to overcome the current limitations are reviewed, focusing on biomaterials design and generation methods for myocardium, heart valves, and blood vessels. Furthermore, novel contact‐ and marker‐free biomaterial and extracellular matrix assessment methods are highlighted. PMID:25778713

Biodegradable Scaffolds for Bone Regeneration Combined with Drug-Delivery Systems in Osteomyelitis Therapy

PubMed Central

Dorati, Rossella; DeTrizio, Antonella; Modena, Tiziana; Conti, Bice; Benazzo, Francesco; Gastaldi, Giulia; Genta, Ida

2017-01-01

A great deal of research is ongoing in the area of tissue engineering (TE) for bone regeneration. A possible improvement in restoring damaged tissues involves the loading of drugs such as proteins, genes, growth factors, antibiotics, and anti-inflammatory drugs into scaffolds for tissue regeneration. This mini-review is focused on the combination of the local delivery of antibiotic agents with bone regenerative therapy for the treatment of a severe bone infection such as osteomyelitis. The review includes a brief explanation of scaffolds for bone regeneration including scaffolds characteristics and types, a focus on severe bone infections (especially osteomyelitis and its treatment), and a literature review of local antibiotic delivery by the combination of scaffolds and drug-delivery systems. Some examples related to published studies on gentamicin sulfate-loaded drug-delivery systems combined with scaffolds are discussed, and future perspectives are highlighted. PMID:29231857

Biomimetic strategies for the glioblastoma microenvironment

NASA Astrophysics Data System (ADS)

Cha, Junghwa; Kim, Pilnam

2017-12-01

Glioblastoma multiforme (GBM) is a devastating type of tumor with high mortality, caused by extensive infiltration into adjacent tissue and rapid recurrence. Most therapies for GBM have focused on the cytotoxicity, and have not targeted GBM spread. However, there have been numerous attempts to improve therapy by addressing GBM invasion, through understanding and mimicking its behavior using three-dimensional (3D) experimental models. Compared with two-dimensional models and in vivo animal models, 3D GBM models can capture the invasive motility of glioma cells within a 3D environment comprising many cellular and non-cellular components. Based on tissue engineering techniques, GBM invasion has been investigated within a biologically relevant environment, from biophysical and biochemical perspectives, to clarify the pro-invasive factors of GBM. This review discusses the recent progress in techniques for modeling the microenvironments of GBM tissue and suggests future directions with respect to recreating the GBM microenvironment and preclinical applications.

Mandibular Repair in Rats with Premineralized Silk Scaffolds and BMP-2-modified bMSCs

PubMed Central

Jiang, Xinquan; Zhao, Jun; Wang, Shaoyi; Sun, Xiaojuan; Zhang, Xiuli; Chen, Jake; Kaplan, David L.; Zhang, Zhiyuan

2010-01-01

Premineralized silk fibroin protein scaffolds (mSS) were prepared to combine the osteoconductive properties of biological apatite with aqueous-derived silk scaffold (SS) as a composite scaffold for bone regeneration. The aim of present study was to evaluate the effect of premineralized silk scaffolds combined with bone morphogenetic protein-2 (BMP-2) modified bone marrow stromal cells (bMSCs) to repair mandibular bony defects in a rat model. bMSCs were expanded and transduced with adenovirus AdBMP-2, AdLacZ gene in vitro. These genetically modified bMSCs were then combined with premineralized silk scaffolds to form tissue engineered bone. Mandibular repairs with AdBMP-2 transduced bMSCs/mSS constructs were compared with those treated with AdLacZ transduced bMSCs/mSS constructs, native (nontransduced) bMSCs/mSS constructs and mSS alone. Eight weeks post-operation, the mandibles were explanted and evaluated by radiographic observation, micro-CT, histological analysis and immunohistochemistry. The presence of BMP-2 gene enhanced tissue engineered bone in terms of the most new bone formed and the highest local bone mineral densities (BMD) found. These results demonstrated that premineralized silk scaffold could serve as a potential substrate for bMSCs to construct tissue engineered bone for mandibular bony defects. BMP-2 gene therapy and tissue engineering techniques could be used in mandibular repair and bone regeneration. PMID:19501905

Nanotechnology in bone tissue engineering.

PubMed

Walmsley, Graham G; McArdle, Adrian; Tevlin, Ruth; Momeni, Arash; Atashroo, David; Hu, Michael S; Feroze, Abdullah H; Wong, Victor W; Lorenz, Peter H; Longaker, Michael T; Wan, Derrick C

2015-07-01

Nanotechnology represents a major frontier with potential to significantly advance the field of bone tissue engineering. Current limitations in regenerative strategies include impaired cellular proliferation and differentiation, insufficient mechanical strength of scaffolds, and inadequate production of extrinsic factors necessary for efficient osteogenesis. Here we review several major areas of research in nanotechnology with potential implications in bone regeneration: 1) nanoparticle-based methods for delivery of bioactive molecules, growth factors, and genetic material, 2) nanoparticle-mediated cell labeling and targeting, and 3) nano-based scaffold construction and modification to enhance physicochemical interactions, biocompatibility, mechanical stability, and cellular attachment/survival. As these technologies continue to evolve, ultimate translation to the clinical environment may allow for improved therapeutic outcomes in patients with large bone deficits and osteodegenerative diseases. Traditionally, the reconstruction of bony defects has relied on the use of bone grafts. With advances in nanotechnology, there has been significant development of synthetic biomaterials. In this article, the authors provided a comprehensive review on current research in nanoparticle-based therapies for bone tissue engineering, which should be useful reading for clinicians as well as researchers in this field. Copyright © 2015 Elsevier Inc. All rights reserved.

[Supervision, administration and standard research related to tissue engineered medical products].

PubMed

Xi, Ting-fei; Chen, Liang; Zhao, Peng

2003-11-01

Tissue engineering advance in supplying the reparative and reconstructive medicine with promising tissue engineered medical products(TEMPs) and the new therapy alternative. The related supervision and administration of TEMPs is being developed and the standard research of TEMPs is also in progress. The Food and Drug Administration(FDA) of the United States has treated TEMPs as combined products and supervised them according to the level of risk to patients. Lately, FDA has determined that the Center for Devices and Radiological Health (CDRH) should take charge of examination and approval of TEMPs, with the cooperation of the Center for Biological Evaluations and Research(CBER). The regulatory controls have been established respectively in European Union and Japan. In China, TEMPs are identified as medical devices combined with cells. The Department of Medical Device of the State Food and Drug Administration (SFDA) is responsible for the examination and approval of TEMPs, and National Institute for the Control of Pharmaceutical & Biological Products(NICPBP) is responsible for evaluation tests. The standards of TEMPs are formulated mainly by the American Society of Testing Materials(ASTM) and International Standardization Organization(ISO).

Applications and Implications of Heparin and Protamine in Tissue Engineering and Regenerative Medicine

PubMed Central

Nemeno, Judee Grace E.; Lee, Kyung Mi

2014-01-01

Drug repositioning is one of the most rapidly emerging fields of study. This concept is anchored on the principle that diseases have similar damaged or affected signaling pathways. Recently, drugs have been repositioned not only for their alternative therapeutic uses but also for their applications as biomaterials in various fields. However, medical drugs as biomaterials are rarely focused on in reviews. Fragmin and protamine have been recently the sources of increasing attention in the field of tissue engineering and regenerative medicine. Fragmin and protamine have been manufactured primarily as a safe antidote for the circulating heparin. Lately, these drugs have been utilized as either micro- or nanoparticle biomaterials. In this paper, we will briefly describe the concept of drug repositioning and some of the medical drugs that have been repurposed for their alternative therapeutic uses. Also, this will feature the historical background of the studies focused on fragmin/protamine micro/nanoparticles (F/P M/NPs) and their applications as biomaterials in tissue engineering, stem cell therapy, and regenerative medicine. PMID:24995338

A Standardized Rat Model of Volumetric Muscle Loss Injury for the Development of Tissue Engineering Therapies

DTIC Science & Technology

2012-12-01

isometric tetanic force (Po) of 28.4% and 32.5% at 2 and 4 months. Importantly, Po corrected for differences in body weight and muscle wet weights were...development, we removed progres- sively larger amounts of muscle tissue followed by a mea- surement of maximal isometric force (Po). The final model, and...indicated by increased collagen deposition (Fig. 2). The scarred area and the area immediately adjacent to it contained disorganized muscle fibers

Potential and problems in ultrasound-responsive drug delivery systems

PubMed Central

Zhao, Ying-Zheng; Du, Li-Na; Lu, Cui-Tao; Jin, Yi-Guang; Ge, Shu-Ping

2013-01-01

Ultrasound is an important local stimulus for triggering drug release at the target tissue. Ultrasound-responsive drug delivery systems (URDDS) have become an important research focus in targeted therapy. URDDS include many different formulations, such as microbubbles, nanobubbles, nanodroplets, liposomes, emulsions, and micelles. Drugs that can be loaded into URDDS include small molecules, biomacromolecules, and inorganic substances. Fields of clinical application include anticancer therapy, treatment of ischemic myocardium, induction of an immune response, cartilage tissue engineering, transdermal drug delivery, treatment of Huntington’s disease, thrombolysis, and disruption of the blood–brain barrier. This review focuses on recent advances in URDDS, and discusses their formulations, clinical application, and problems, as well as a perspective on their potential use in the future. PMID:23637531

Potential feasibility of dental stem cells for regenerative therapies: stem cell transplantation and whole-tooth engineering.

PubMed

Nakahara, Taka

2011-07-01

Multipotent mesenchymal stem cells from bone marrow are expected to be a somatic stem cell source for the development of new cell-based therapy in regenerative medicine. However, dental clinicians are unlikely to carry out autologous cell/tissue collection from patients (i.e., marrow aspiration) as a routine procedure in their clinics; hence, the utilization of bone marrow stem cells seems impractical in the dental field. Dental tissues harvested from extracted human teeth are well known to contain highly proliferative and multipotent stem cell compartments and are considered to be an alternative autologous cell source in cell-based medicine. This article provides a short overview of the ongoing studies for the potential application of dental stem cells and suggests the utilization of 2 concepts in future regenerative medicine: (1) dental stem cell-based therapy for hepatic and other systemic diseases and (2) tooth replacement therapy using the bioengineered human whole tooth, called the "test-tube dental implant." Regenerative therapies will bring new insights and benefits to the fields of clinical medicine and dentistry.

Papilla regeneration by injectable stem cell therapy with regenerative medicine: long-term clinical prognosis.

PubMed

Yamada, Yoichi; Nakamura, Sayaka; Ueda, Minoru; Ito, Kenji

2015-03-01

Black triangle (BT), an open interproximal space between teeth, can cause aesthetic concerns, food impaction, phonetic difficulties and periodontitis. The aim of this study was to determine the possibility and long-term prognosis of novel papilla regeneration with regenerative medicine, i.e. tissue-engineered papilla (TEP), and to investigate the potential of a tissue-engineering method for soft-tissue augmentation, especially aesthetic improvement of BT, with mesenchymal stem cells (MSCs) as the isolated cells, platelet-rich plasma (PRP) as the growth factor and hyaluronic acid (HA) as the scaffold. The parameters were assessed from a clinical point of view by measuring the distance from the tip of the interproximal papilla to the base of the contact area in each study region. The mean volumes, operation times and follow-up periods of TEP were 1.32 ± 0.25 ml, 2.2 ± 1.62 times and 55.3 ± 17.7 months; the mean improved BT values were 2.55 ± 0.89 mm. An aesthetic improvement was achieved. TEP was able to provide aesthetic improvement of black triangle and predictable results, and could emerge as another novel option for periodontal regenerative therapy in periodontal diseases. Copyright © 2013 John Wiley & Sons, Ltd.

In vitro simulation of pathological bone conditions to predict clinical outcome of bone tissue engineered materials

NASA Astrophysics Data System (ADS)

Nguyen, Duong Thuy Thi

According to the Centers for Disease Control, the geriatric population of ≥65 years of age will increase to 51.5 million in 2020; 40% of white women and 13% of white men will be at risk for fragility fractures or fractures sustained under normal stress and loading conditions due to bone disease, leading to hospitalization and surgical treatment. Fracture management strategies can be divided into pharmaceutical therapy, surgical intervention, and tissue regeneration for fracture prevention, fracture stabilization, and fracture site regeneration, respectively. However, these strategies fail to accommodate the pathological nature of fragility fractures, leading to unwanted side effects, implant failures, and non-unions. Compromised innate bone healing reactions of patients with bone diseases are exacerbated with protective bone therapy. Once these patients sustain a fracture, bone healing is a challenge, especially when fracture stabilization is unsuccessful. Traditional stabilizing screw and plate systems were designed with emphasis on bone mechanics rather than biology. Bone grafts are often used with fixation devices to provide skeletal continuity at the fracture gap. Current bone grafts include autologous bone tissue and donor bone tissue; however, the quality and quantity demanded by fragility fractures sustained by high-risk geriatric patients and patients with bone diseases are not met. Consequently, bone tissue engineering strategies are advancing towards functionalized bone substitutes to provide fracture reconstruction while effectively mediating bone healing in normal and diseased fracture environments. In order to target fragility fractures, fracture management strategies should be tailored to allow bone regeneration and fracture stabilization with bioactive bone substitutes designed for the pathological environment. The clinical outcome of these materials must be predictable within various disease environments. Initial development of a targeted treatment strategy should focus on simulating, in vitro, a physiological bone environment to predict clinical effectiveness of engineered bone and understand cellular responses due to the proposed agents and bioactive scaffolds. An in vitro test system can be the necessary catalyst to reduce implant failures and non-unions in fragility fractures.

Magnetic responsive cell based strategies for diagnostic and therapeutics.

PubMed

Gonçalves, Ana I; Miranda, Margarida S; Rodrigues, Márcia T; Reis, Rui Luis; Gomes, Manuela

2018-05-24

The potential of magnetically assisted strategies within the remit of cell-based therapies is increasing and creates new opportunities in biomedical platforms and in the field of tissue engineering and regenerative medicine (TERM). Among the magnetic elements approached to build magnetically responsive strategies, superparamagnetic iron oxide nanoparticles (SPIONs) represent tunable and precise tools whose properties can be modelled for detection, diagnosis, targeting and therapy purposes. The most investigated clinical role of SPIONs is as contrast imaging agents for tracking and monitoring cells and tissues. Nevertheless, magnetic detection also includes biomarker mapping, cell labelling and cell/drug targeting to monitor cell events and anticipate the disruption of homeostatic conditions and progression of disease. Additionally, isolation and screening techniques of cell subsets in heterogeneous populations or of proteins of interest have been explored in a magnetic sorting context. More recently, SPIONs-based technologies have been applied to stimulate cell differentiation and mechanotransduction processes and to transport genetic or drug cargo to study biological mechanisms and contribute for improved therapies. Magnetically based strategies significantly contribute for magnetic tissue engineering (magTE), in which magnetically responsive actuators built from magnetic labelled cells or magnetic functionalized systems can be remotely controlled and spatially manipulated upon the actuation of an external magnetic field for delivery or target of TE solutions. SPIONs functionalities combined with the magnetic responsiveness in multifactorial magnetically assisted platforms can revolutionize diagnosis and therapeutics providing new diagnosis and theranostic tools, encouraging regenerative medicine approaches and holding potential for more effective therapies. This review will address the contribution of SPIONs based technologies as multifunctional tools in boosting magnetically assisted cell based strategies to explore diagnostics and tracking solutions on the detection and analysis of pathologies and to generate improved treatments and therapies, envisioning precise and customized answers for the management of numerous diseases. . © 2018 IOP Publishing Ltd.

Measurement uncertainty evaluation of cellular spheroids surface tension in compressing tests using Young-Laplace equation

NASA Astrophysics Data System (ADS)

Beatrici, Anderson; Santos Baptista, Leandra; Mauro Granjeiro, José

2018-03-01

Regenerative Medicine comprises the Biotechnology, Tissue Engineering and Biometrology for stem cell therapy. Starting from stem cells extracted from the patient, autologous implant, these cells are cultured and differentiated into other tissues, for example, articular cartilage. These cells are reorganized into microspheres (cell spheroids). Such tissue units are recombined into functional tissues constructs that can be implanted in the injured region for regeneration. It is necessary the biomechanical characterization of these constructed to determine if their properties are similar to native tissue. In this study was carried out the modeling of the calculation of uncertainty of the surface tension of cellular spheroids with the use of the Young-Laplace equation. We obtained relative uncertainties about 10%.

Business oriented EU human cell and tissue product legislation will adversely impact Member States' health care systems.

PubMed

Pirnay, Jean-Paul; Vanderkelen, Alain; De Vos, Daniel; Draye, Jean-Pierre; Rose, Thomas; Ceulemans, Carl; Ectors, Nadine; Huys, Isabelle; Jennes, Serge; Verbeken, Gilbert

2013-12-01

The transplantation of conventional human cell and tissue grafts, such as heart valve replacements and skin for severely burnt patients, has saved many lives over the last decades. The late eighties saw the emergence of tissue engineering with the focus on the development of biological substitutes that restore or improve tissue function. In the nineties, at the height of the tissue engineering hype, industry incited policymakers to create a European regulatory environment, which would facilitate the emergence of a strong single market for tissue engineered products and their starting materials (human cells and tissues). In this paper we analyze the elaboration process of this new European Union (EU) human cell and tissue product regulatory regime-i.e. the EU Cell and Tissue Directives (EUCTDs) and the Advanced Therapy Medicinal Product (ATMP) Regulation and evaluate its impact on Member States' health care systems. We demonstrate that the successful lobbying on key areas of regulatory and policy processes by industry, in congruence with Europe's risk aversion and urge to promote growth and jobs, led to excessively business oriented legislation. Expensive industry oriented requirements were introduced and contentious social and ethical issues were excluded. We found indications that this new EU safety and health legislation will adversely impact Member States' health care systems; since 30 December 2012 (the end of the ATMP transitional period) there is a clear threat to the sustainability of some lifesaving and established ATMPs that were provided by public health institutions and small and medium-sized enterprises under the frame of the EUCTDs. In the light of the current economic crisis it is not clear how social security systems will cope with the inflation of costs associated with this new regulatory regime and how priorities will be set with regard to reimbursement decisions. We argue that the ATMP Regulation should urgently be revised to focus on delivering affordable therapies to all who are in need of them and this without necessarily going to the market. The most rapid and elegant way to achieve this would be for the European Commission to publish an interpretative document on "placing on the market of ATMPs," which keeps tailor-made and niche ATMPs outside of the scope of the medicinal product regulation.

Bone regeneration: stem cell therapies and clinical studies in orthopaedics and traumatology

PubMed Central

Gómez-Barrena, Enrique; Rosset, Philippe; Müller, Ingo; Giordano, Rosaria; Bunu, Carmen; Layrolle, Pierre; Konttinen, Yrjö T; Luyten, Frank P

2011-01-01

Abstract Regenerative medicine seeks to repair or replace damaged tissues or organs, with the goal to fully restore structure and function without the formation of scar tissue. Cell based therapies are promising new therapeutic approaches in regenerative medicine. By using mesenchymal stem cells, good results have been reported for bone engineering in a number of clinical studies, most of them investigator initiated trials with limited scope with respect to controls and outcome. With the implementation of a new regulatory framework for advanced therapeutic medicinal products, the stage is set to improve both the characterization of the cells and combination products, and pave the way for improved controlled and well-designed clinical trials. The incorporation of more personalized medicine approaches, including the use of biomarkers to identify the proper patients and the responders to treatment, will be contributing to progress in the field. Both translational and clinical research will move the boundaries in the field of regenerative medicine, and a coordinated effort will provide the clinical breakthroughs, particularly in the many applications of bone engineering. PMID:21251219

The potential of mesenchymal stem cells derived from amniotic membrane and amniotic fluid for neuronal regenerative therapy

PubMed Central

Kim, Eun Young; Lee, Kyung-Bon; Kim, Min Kyu

2014-01-01

The mesenchymal stem cells (MSCs), which are derived from the mesoderm, are considered as a readily available source for tissue engineering. They have multipotent differentiation capacity and can be differentiated into various cell types. Many studies have demonstrated that the MSCs identified from amniotic membrane (AM-MSCs) and amniotic fluid (AF-MSCs) are shows advantages for many reasons, including the possibility of noninvasive isolation, multipotency, self-renewal, low immunogenicity, anti-inflammatory and nontumorigenicity properties, and minimal ethical problem. The AF-MSCs and AM-MSCs may be appropriate sources of mesenchymal stem cells for regenerative medicine, as an alternative to embryonic stem cells (ESCs). Recently, regenerative treatments such as tissue engineering and cell transplantation have shown potential in clinical applications for degenerative diseases. Therefore, amnion and MSCs derived from amnion can be applied to cell therapy in neuro-degeneration diseases. In this review, we will describe the potential of AM-MSCs and AF-MSCs, with particular focus on cures for neuronal degenerative diseases. [BMB Reports 2014; 47(3): 135-140] PMID:24499672

Regenerative Endodontics: A Road Less Travelled

PubMed Central

Bansal, Ramta; Mittal, Sunandan; Kumar, Tarun; Kaur, Dilpreet

2014-01-01

Although traditional approaches like root canal therapy and apexification procedures have been successful in treating diseased or infected root canals, but these modalities fail to re-establish healthy pulp tissue in treated teeth. Regeneration-based approaches aims to offer high levels of success by replacing diseased or necrotic pulp tissues with healthy pulp tissue to revitalize teeth. The applications of regenerative approaches in dental clinics have potential to dramatically improve patients’ quality of life. This review article offers a detailed overview of present regenerative endodontic approaches aiming to revitalize teeth and also outlines the problems to be dealt before this emerging field contributes to clinical treatment protocols. It conjointly covers the basic trilogy elements of tissue engineering. PMID:25478476

The oral and craniofacial relevance of chemically modified RNA therapeutics.

PubMed

Elangovan, Satheesh; Kormann, Michael S D; Khorsand, Behnoush; Salem, Aliasger K

2016-01-01

Several tissue engineering strategies in the form of protein therapy, gene therapy, cell therapy, and their combinations are currently being explored for oral and craniofacial regeneration and repair. Though each of these approaches has advantages, they all have common inherent drawbacks of being expensive and raising safety concerns. Using RNA (encoding therapeutic protein) has several advantages that have the potential to overcome these limitations. Chemically modifying the RNA improves its stability and mitigates immunogenicity allowing for the potential of RNA to become an alternative to protein and gene based therapies. This brief review article focuses on the potential of RNA therapeutics in the treatment of disorders in the oral and craniofacial regions.

The Oral and Craniofacial Relevance of Chemically Modified RNA Therapeutics

PubMed Central

Kormann, Michael S.D.; Khorsand, Behnoush

2016-01-01

Several tissue engineering strategies in the form of protein therapy, gene therapy, cell therapy and its combinations are currently being explored for oral and cranio-facial regeneration and repair. Though each of these approaches has advantages, they all have common inherent drawbacks of being expensive and raising safety concerns. Using RNA (encoding therapeutic protein) has several advantages that have the potential to overcome these limitations. Chemically modifying the RNA improves its stability and mitigates immunogenicity allowing for the potential of RNA to become an alternative to protein and gene based therapies. This brief review article focuses on the potential of RNA therapeutics in the treatment of disorders in the oral and craniofacial regions. PMID:26896600

Biomaterials innovation for next generation ex vivo immune tissue engineering.

PubMed

Singh, Ankur

2017-06-01

Primary and secondary lymphoid organs are tissues that facilitate differentiation of B and T cells, leading to the induction of adaptive immune responses. These organs are present in the body from birth and are also recognized as locations where self-reactive B and T cells can be eliminated during the natural selection process. Many insights into the mechanisms that control the process of immune cell development and maturation in response to infection come from the analysis of various gene-deficient mice that lack some or all hallmark features of lymphoid tissues. The complexity of such animal models limits our ability to modulate the parameters that control the process of immune cell development, differentiation, and immunomodulation. Engineering functional, living immune tissues using biomaterials can grant researchers the ability to reproduce immunological events with tunable parameters for more rapid development of immunotherapeutics, cell-based therapy, and enhancing our understanding of fundamental biology as well as improving efforts in regenerative medicine. Here the author provides his review and perspective on the bioengineering of primary and secondary lymphoid tissues, and biomaterials innovation needed for the construction of these immune organs in tissue culture plates and on-chip. Copyright © 2017 Elsevier Ltd. All rights reserved.

Versatile graphene biosensors for enhancing human cell therapy.

PubMed

Vlăsceanu, George M; Amărandi, Roxana-Maria; Ioniță, Mariana; Tite, Teddy; Iovu, Horia; Pilan, Luisa; Burns, Jorge S

2018-05-01

Technological advances in engineering and cell biology stimulate novel approaches for medical treatment, in particular cell-based therapy. The first cell-based gene therapy against cancer was recently approved by the US Food and Drug Administration. Progress in cancer diagnosis includes a blood test detecting five cancer types. Numerous stem cell phase I/II clinical trials showing safety and efficacy will soon pursue qualifying criteria for advanced therapy medicinal products (ATMP), aspiring to join the first stem-cell therapy approved by the European Medicines Agency. Cell based therapy requires extensive preclinical characterisation of biomarkers indicating mechanisms of action crucial to the desired therapeutic effect. Quantitative analyses monitoring critical functions for the manufacture of optimal cell and tissue-based clinical products include successful potency assays for implementation. The challenge to achieve high quality measurement is increasingly met by progress in biosensor design. We adopt a cell therapy perspective to highlight recent examples of graphene-enhanced biointerfaces for measurement of biomarkers relevant to cancer treatment, diagnosis and tissue regeneration. Graphene based biosensor design problems can thwart their use for health care transformative point of care testing and real-time applications. We discuss concerns to be addressed and emerging solutions for establishing clinical grade biosensors to accelerate human cell therapy. Copyright © 2018 Elsevier B.V. All rights reserved.

Antibody engineering of a cytotoxic monoclonal antibody 84 against human embryonic stem cells: Investigating the effects of multivalency on cytotoxicity.

PubMed

Klement, Maximilian; Zheng, Jiyun; Liu, Chengcheng; Tan, Heng-Liang; Wong, Victor Vai Tak; Choo, Andre Boon-Hwa; Lee, Dong-Yup; Ow, Dave Siak-Wei

2017-02-10

Antibody fragments have shown targeted specificity to their antigens, but only modest tissue retention times in vivo and in vitro. Multimerization has been used as a protein engineering tool to increase the number of binding units and thereby enhance the efficacy and retention time of antibody fragments. In this work, we explored the effects of valency using a series of self-assembling polypeptides based on the GCN4 leucine zipper multimerization domain fused to a single-chain variable fragment via an antibody upper hinge sequence. Four engineered antibody fragments with a valency from one to four antigen-binding units of a cytotoxic monoclonal antibody 84 against human embryonic stem cells (hESC) were constructed. We hypothesized that higher cytotoxicity would be observed for fragments with increased valency. Flow cytometry analysis revealed that the trimeric and tetrameric engineered antibody fragments resulted in the highest degree of cytotoxicity to the undifferentiated hESC, while the engineered antibody fragments were observed to have improved tissue penetration into cell clusters. Thus, a trade off was made for the trimeric versus tetrameric fragment due to improved tissue penetration. These results have direct implications for antibody-mediated removal of undifferentiated hESC during regenerative medicine and cell therapy. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

Tissue engineering: construction of a multicellular 3D scaffold for the delivery of layered cell sheets.

PubMed

Turner, William S; Sandhu, Nabjot; McCloskey, Kara E

2014-10-03

Many tissues, such as the adult human hearts, are unable to adequately regenerate after damage.(2,3) Strategies in tissue engineering propose innovations to assist the body in recovery and repair. For example, TE approaches may be able to attenuate heart remodeling after myocardial infarction (MI) and possibly increase total heart function to a near normal pre-MI level.(4) As with any functional tissue, successful regeneration of cardiac tissue involves the proper delivery of multiple cell types with environmental cues favoring integration and survival of the implanted cell/tissue graft. Engineered tissues should address multiple parameters including: soluble signals, cell-to-cell interactions, and matrix materials evaluated as delivery vehicles, their effects on cell survival, material strength, and facilitation of cell-to-tissue organization. Studies employing the direct injection of graft cells only ignore these essential elements.(2,5,6) A tissue design combining these ingredients has yet to be developed. Here, we present an example of integrated designs using layering of patterned cell sheets with two distinct types of biological-derived materials containing the target organ cell type and endothelial cells for enhancing new vessels formation in the "tissue". Although these studies focus on the generation of heart-like tissue, this tissue design can be applied to many organs other than heart with minimal design and material changes, and is meant to be an off-the-shelf product for regenerative therapies. The protocol contains five detailed steps. A temperature sensitive Poly(N-isopropylacrylamide) (pNIPAAM) is used to coat tissue culture dishes. Then, tissue specific cells are cultured on the surface of the coated plates/micropattern surfaces to form cell sheets with strong lateral adhesions. Thirdly, a base matrix is created for the tissue by combining porous matrix with neovascular permissive hydrogels and endothelial cells. Finally, the cell sheets are lifted from the pNIPAAM coated dishes and transferred to the base element, making the complete construct.

New bioactive motifs and their use in functionalized self-assembling peptides for NSC differentiation and neural tissue engineering

NASA Astrophysics Data System (ADS)

Gelain, F.; Cigognini, D.; Caprini, A.; Silva, D.; Colleoni, B.; Donegá, M.; Antonini, S.; Cohen, B. E.; Vescovi, A.

2012-04-01

Developing functionalized biomaterials for enhancing transplanted cell engraftment in vivo and stimulating the regeneration of injured tissues requires a multi-disciplinary approach customized for the tissue to be regenerated. In particular, nervous tissue engineering may take a great advantage from the discovery of novel functional motifs fostering transplanted stem cell engraftment and nervous fiber regeneration. Using phage display technology we have discovered new peptide sequences that bind to murine neural stem cell (NSC)-derived neural precursor cells (NPCs), and promote their viability and differentiation in vitro when linked to LDLK12 self-assembling peptide (SAPeptide). We characterized the newly functionalized LDLK12 SAPeptides via atomic force microscopy, circular dichroism and rheology, obtaining nanostructured hydrogels that support human and murine NSC proliferation and differentiation in vitro. One functionalized SAPeptide (Ac-FAQ), showing the highest stem cell viability and neural differentiation in vitro, was finally tested in acute contusive spinal cord injury in rats, where it fostered nervous tissue regrowth and improved locomotor recovery. Interestingly, animals treated with the non-functionalized LDLK12 had an axon sprouting/regeneration intermediate between Ac-FAQ-treated animals and controls. These results suggest that hydrogels functionalized with phage-derived peptides may constitute promising biomimetic scaffolds for in vitro NSC differentiation, as well as regenerative therapy of the injured nervous system. Moreover, this multi-disciplinary approach can be used to customize SAPeptides for other specific tissue engineering applications.Developing functionalized biomaterials for enhancing transplanted cell engraftment in vivo and stimulating the regeneration of injured tissues requires a multi-disciplinary approach customized for the tissue to be regenerated. In particular, nervous tissue engineering may take a great advantage from the discovery of novel functional motifs fostering transplanted stem cell engraftment and nervous fiber regeneration. Using phage display technology we have discovered new peptide sequences that bind to murine neural stem cell (NSC)-derived neural precursor cells (NPCs), and promote their viability and differentiation in vitro when linked to LDLK12 self-assembling peptide (SAPeptide). We characterized the newly functionalized LDLK12 SAPeptides via atomic force microscopy, circular dichroism and rheology, obtaining nanostructured hydrogels that support human and murine NSC proliferation and differentiation in vitro. One functionalized SAPeptide (Ac-FAQ), showing the highest stem cell viability and neural differentiation in vitro, was finally tested in acute contusive spinal cord injury in rats, where it fostered nervous tissue regrowth and improved locomotor recovery. Interestingly, animals treated with the non-functionalized LDLK12 had an axon sprouting/regeneration intermediate between Ac-FAQ-treated animals and controls. These results suggest that hydrogels functionalized with phage-derived peptides may constitute promising biomimetic scaffolds for in vitro NSC differentiation, as well as regenerative therapy of the injured nervous system. Moreover, this multi-disciplinary approach can be used to customize SAPeptides for other specific tissue engineering applications. Electronic supplementary information (ESI) available: Supporting methods and data about CD spectral analysis of SAPeptide solutions (Fig. S1), neural differentiation of murine and human NSCs (Fig. S2) on SAPeptide scaffolds, and their statistical analysis (Table S1). See DOI: 10.1039/c2nr30220a

The application of multiple biophysical cues to engineer functional neocartilage for treatment of osteoarthritis. Part I: cellular response.

PubMed

Brady, Mariea A; Waldman, Stephen D; Ethier, C Ross

2015-02-01

Osteoarthritis (OA) is a complex disease of the joint for which current treatments are unsatisfactory, thus motivating development of tissue engineering (TE)-based therapies. To date, TE strategies have had some success, developing replacement tissue constructs with biochemical properties approaching that of native cartilage. However, poor biomechanical properties and limited postimplantation integration with surrounding tissue are major shortcomings that need to be addressed. Functional tissue engineering strategies that apply physiologically relevant biophysical cues provide a platform to improve TE constructs before implantation. In the previous decade, new experimental and theoretical findings in cartilage biomechanics and electromechanics have emerged, resulting in an increased understanding of the complex interplay of multiple biophysical cues in the extracellular matrix of the tissue. The effect of biophysical stimulation on cartilage, and the resulting chondrocyte-mediated biosynthesis, remodeling, degradation, and repair, has, therefore, been extensively explored by the TE community. This article compares and contrasts the cellular response of chondrocytes to multiple biophysical stimuli, and may be read in conjunction with its companion paper that compares and contrasts the subsequent intracellular signal transduction cascades. Mechanical, magnetic, and electrical stimuli promote proliferation, differentiation, and maturation of chondrocytes within established dose parameters or "biological windows." This knowledge will provide a framework for ongoing studies incorporating multiple biophysical cues in TE functional neocartilage for treatment of OA.

TexMi: Development of Tissue-Engineered Textile-Reinforced Mitral Valve Prosthesis

PubMed Central

Moreira, Ricardo; Gesche, Valentine N.; Hurtado-Aguilar, Luis G.; Schmitz-Rode, Thomas; Frese, Julia

2014-01-01

Mitral valve regurgitation together with aortic stenosis is the most common valvular heart disease in Europe and North America. Mechanical and biological prostheses available for mitral valve replacement have significant limitations such as the need of a long-term anticoagulation therapy and failure by calcifications. Both types are unable to remodel, self-repair, and adapt to the changing hemodynamic conditions. Moreover, they are mostly designed for the aortic position and do not reproduce the native annular-ventricular continuity, resulting in suboptimal hemodynamics, limited durability, and gradually decreasing ventricular pumping efficiency. A tissue-engineered heart valve specifically designed for the mitral position has the potential to overcome the limitations of the commercially available substitutes. For this purpose, we developed the TexMi, a living textile-reinforced mitral valve, which recapitulates the key elements of the native one: annulus, asymmetric leaflets (anterior and posterior), and chordae tendineae to maintain the native annular-ventricular continuity. The tissue-engineered valve is based on a composite scaffold consisting of the fibrin gel as a cell carrier and a textile tubular structure with the twofold task of defining the gross three-dimensional (3D) geometry of the valve and conferring mechanical stability. The TexMi valves were molded with ovine umbilical vein cells and stimulated under dynamic conditions for 21 days in a custom-made bioreactor. Histological and immunohistological stainings showed remarkable tissue development with abundant aligned collagen fibers and elastin deposition. No cell-mediated tissue contraction occurred. This study presents the proof-of-principle for the realization of a tissue-engineered mitral valve with a simple and reliable injection molding process readily adaptable to the patient's anatomy and pathological situation by producing a patient-specific rapid prototyped mold. PMID:24665896

Rapid fabrication of detachable three-dimensional tissues by layering of cell sheets with heating centrifuge.

PubMed

Haraguchi, Yuji; Kagawa, Yuki; Hasegawa, Akiyuki; Kubo, Hirotsugu; Shimizu, Tatsuya

2018-01-18

Confluent cultured cells on a temperature-responsive culture dish can be harvested as an intact cell sheet by decreasing temperature below 32°C. A three-dimensional (3-D) tissue can be fabricated by the layering of cell sheets. A resulting 3-D multilayered cell sheet-tissue on a temperature-responsive culture dish can be also harvested without any damage by only temperature decreasing. For shortening the fabrication time of the 3-D multilayered constructs, we attempted to layer cell sheets on a temperature-responsive culture dish with centrifugation. However, when a cell sheet was attached to the culture surface with a conventional centrifuge at 22-23°C, the cell sheet hardly adhere to the surface due to its noncell adhesiveness. Therefore, in this study, we have developed a heating centrifuge. In centrifugation (55g) at 36-37°C, the cell sheet adhered tightly within 5 min to the dish without significant cell damage. Additionally, centrifugation accelerated the cell sheet-layering process. The heating centrifugation shortened the fabrication time by one-fifth compared to a multilayer tissue fabrication without centrifugation. Furthermore, the multilayered constructs were finally detached from the dishes by decreasing temperature. This rapid tissue-fabrication method will be used as a valuable tool in the field of tissue engineering and regenerative therapy. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

Chitosan/silk fibroin-based, Schwann cell-derived extracellular matrix-modified scaffolds for bridging rat sciatic nerve gaps.

PubMed

Gu, Yun; Zhu, Jianbin; Xue, Chengbin; Li, Zhenmeiyu; Ding, Fei; Yang, Yumin; Gu, Xiaosong

2014-02-01

Extracellular matrix (ECM) plays a prominent role in establishing and maintaining an ideal microenvironment for tissue regeneration, and ECM scaffolds are used as a feasible alternative to cellular and molecular therapy in the fields of tissue engineering. Because of their advantages over tissue-derived ECM scaffolds, cultured cell-derived ECM scaffolds are beginning to attract attention, but they have been scarcely studied for peripheral nerve repair. Here we aimed to develop a tissue engineered nerve scaffold by reconstituting nerve cell-derived ECM with natural biomaterials. A protocol was adopted to prepare and characterize the cultured Schwann cell (SC)-derived ECM. A chitosan conduit and silk fibroin (SF) fibers were prepared, cultured with SCs for ECM deposition, and subjected to decellularization, followed by assembly into a chitosan/SF-based, SC-derived ECM-modified scaffold, which was used to bridge a 10 mm rat sciatic nerve gap. The results from morphological analysis as well as electrophysiological examination indicated that regenerative outcomes achieved by our developed scaffold were similar to those by an acellular nerve graft (namely a nerve tissue-derived ECM scaffold), but superior to those by a plain chitosan/SF scaffold. Moreover, blood and histopathological parameters confirmed the safety of scaffold modification by SC-derived ECM. Therefore, a hybrid scaffold based on joint use of acellular and classical biomaterials represents a promising approach to nerve tissue engineering. Copyright © 2013 Elsevier Ltd. All rights reserved.

Role of nanotopography in the development of tissue engineered 3D organs and tissues using mesenchymal stem cells.

PubMed

Salmasi, Shima; Kalaskar, Deepak M; Yoon, Wai-Weng; Blunn, Gordon W; Seifalian, Alexander M

2015-03-26

Recent regenerative medicine and tissue engineering strategies (using cells, scaffolds, medical devices and gene therapy) have led to fascinating progress of translation of basic research towards clinical applications. In the past decade, great deal of research has focused on developing various three dimensional (3D) organs, such as bone, skin, liver, kidney and ear, using such strategies in order to replace or regenerate damaged organs for the purpose of maintaining or restoring organs' functions that may have been lost due to aging, accident or disease. The surface properties of a material or a device are key aspects in determining the success of the implant in biomedicine, as the majority of biological reactions in human body occur on surfaces or interfaces. Furthermore, it has been established in the literature that cell adhesion and proliferation are, to a great extent, influenced by the micro- and nano-surface characteristics of biomaterials and devices. In addition, it has been shown that the functions of stem cells, mesenchymal stem cells in particular, could be regulated through physical interaction with specific nanotopographical cues. Therefore, guided stem cell proliferation, differentiation and function are of great importance in the regeneration of 3D tissues and organs using tissue engineering strategies. This review will provide an update on the impact of nanotopography on mesenchymal stem cells for the purpose of developing laboratory-based 3D organs and tissues, as well as the most recent research and case studies on this topic.

Electroactive 3D materials for cardiac tissue engineering

NASA Astrophysics Data System (ADS)

Gelmi, Amy; Zhang, Jiabin; Cieslar-Pobuda, Artur; Ljunngren, Monika K.; Los, Marek Jan; Rafat, Mehrdad; Jager, Edwin W. H.

2015-04-01

By-pass surgery and heart transplantation are traditionally used to restore the heart's functionality after a myocardial Infarction (MI or heart attack) that results in scar tissue formation and impaired cardiac function. However, both procedures are associated with serious post-surgical complications. Therefore, new strategies to help re-establish heart functionality are necessary. Tissue engineering and stem cell therapy are the promising approaches that are being explored for the treatment of MI. The stem cell niche is extremely important for the proliferation and differentiation of stem cells and tissue regeneration. For the introduction of stem cells into the host tissue an artificial carrier such as a scaffold is preferred as direct injection of stem cells has resulted in fast stem cell death. Such scaffold will provide the proper microenvironment that can be altered electronically to provide temporal stimulation to the cells. We have developed an electroactive polymer (EAP) scaffold for cardiac tissue engineering. The EAP scaffold mimics the extracellular matrix and provides a 3D microenvironment that can be easily tuned during fabrication, such as controllable fibre dimensions, alignment, and coating. In addition, the scaffold can provide electrical and electromechanical stimulation to the stem cells which are important external stimuli to stem cell differentiation. We tested the initial biocompatibility of these scaffolds using cardiac progenitor cells (CPCs), and continued onto more sensitive induced pluripotent stem cells (iPS). We present the fabrication and characterisation of these electroactive fibres as well as the response of increasingly sensitive cell types to the scaffolds.

Gene delivery for periodontal tissue engineering: current knowledge - future possibilities.

PubMed

Chen, Fa-Ming; Ma, Zhi-Wei; Wang, Qin-Tao; Wu, Zhi-Fen

2009-08-01

The cellular and molecular events of periodontal healing are coordinated and regulated by an elaborate system of signaling molecules, pointing to a primary strategy for functional periodontal compartment regeneration to replicate components of the natural cellular microenvironment by providing an artificial extracellular matrix (ECM) and by delivering growth factors. However, even with optimal carriers, the localized delivery of growth factors often requires a large amount of protein to stimulate significant effects in vivo, which increases the risk and unwanted side effects. A simple and relatively new approach to bypassing this dilemma involves converting cells into protein producing factories. This is done by a so-called gene delivery method, where therapeutic agents to be delivered are DNA plasmids that include the gene encoding desired growth factors instead of recombinant proteins. As localized depots of genes, novel gene delivery systems have the potential to release their cargo in a sustained and controlled manner and finally provide time- and space- dependent levels of encoded proteins during all stages of tissue regrowth, offering great versatility in their application and prompting new tissue engineering strategy in periodontal regenerative medicine. However, gene therapy in Periodontology is clearly in its infancy. Significant efforts still need to be made in developing safe and effective delivery platforms and clarifying how gene delivery, in combination with tissue engineering, may mimic the critical aspects of natural biological processes occurring in periodontal development and repair. The aim of this review is to trace an outline of the state-of-the-art in the application of gene delivery and tissue engineering strategies for periodontal healing and regeneration.

Cryopreservation Method for the Effective Collection of Dental Pulp Stem Cells.

PubMed

Takebe, Yusuke; Tatehara, Seiko; Fukushima, Tatsuhiro; Tokuyama-Toda, Reiko; Yasuhara, Rika; Mishima, Kenji; Satomura, Kazuhito

2017-05-01

Dental pulp stem cells (DPSCs) are an attractive cell source for use in cell-based therapy, regenerative medicine, and tissue engineering because DPSCs have a high cell proliferation ability and multidifferentiation capacity. However, several problems are associated with the collection and preservation of DPSCs for use in future cell-based therapy. In particular, the isolation of DPSCs for cryopreservation is time consuming and expensive. In this study, we developed a novel cryopreservation method (NCM) for dental pulp tissues to isolate suitable DPSCs after thawing cryopreserved tissue. Using the NCM, dental pulp tissues were cultured on adhesion culture dishes for 5 days and then cryopreserved. After thawing, the cryopreserved dental pulp tissue fragments exhibited cell migration. We evaluated each property of DPSCs isolated using the NCM (DPSCs-NCM) and the explant method alone without cryopreservation (DPSCs-C). DPSCs-NCM had the same proliferation capacity as DPSCs-C. Flow cytometry (FACS) analysis indicated that both DPSCs-NCM and DPSCs-C were positive for mesenchymal stem cell markers at the same level but negative for hematopoietic cell markers. Moreover, both DPSCs-NCM and DPSCs-C could differentiate into osteogenic, chondrogenic, and adipogenic cells during culture in each induction medium. These results suggest that DPSCs-NCM may be mesenchymal stem cells. Therefore, our novel method might facilitate the less expensive cryopreservation of DPSCs, thereby providing suitable DPSCs for use in patients in future cell-based therapies.

Dental pulp stem cells as a multifaceted tool for bioengineering and the regeneration of craniomaxillofacial tissues

PubMed Central

Aurrekoetxea, Maitane; Garcia-Gallastegui, Patricia; Irastorza, Igor; Luzuriaga, Jon; Uribe-Etxebarria, Verónica; Unda, Fernando; Ibarretxe, Gaskon

2015-01-01

Dental pulp stem cells, or DPSC, are neural crest-derived cells with an outstanding capacity to differentiate along multiple cell lineages of interest for cell therapy. In particular, highly efficient osteo/dentinogenic differentiation of DPSC can be achieved using simple in vitro protocols, making these cells a very attractive and promising tool for the future treatment of dental and periodontal diseases. Among craniomaxillofacial organs, the tooth and salivary gland are two such cases in which complete regeneration by tissue engineering using DPSC appears to be possible, as research over the last decade has made substantial progress in experimental models of partial or total regeneration of both organs, by cell recombination technology. Moreover, DPSC seem to be a particularly good choice for the regeneration of nerve tissues, including injured or transected cranial nerves. In this context, the oral cavity appears to be an excellent testing ground for new regenerative therapies using DPSC. However, many issues and challenges need yet to be addressed before these cells can be employed in clinical therapy. In this review, we point out some important aspects on the biology of DPSC with regard to their use for the reconstruction of different craniomaxillofacial tissues and organs, with special emphasis on cranial bones, nerves, teeth, and salivary glands. We suggest new ideas and strategies to fully exploit the capacities of DPSC for bioengineering of the aforementioned tissues. PMID:26528190

Tendon and ligament as novel cell sources for engineering the knee meniscus.

PubMed

Hadidi, P; Paschos, N K; Huang, B J; Aryaei, A; Hu, J C; Athanasiou, K A

2016-12-01

The application of cell-based therapies in regenerative medicine is hindered by the difficulty of acquiring adequate numbers of competent cells. For the knee meniscus in particular, this may be solved by harvesting tissue from neighboring tendons and ligaments. In this study, we have investigated the potential of cells from tendon and ligament, as compared to meniscus cells, to engineer scaffold-free self-assembling fibrocartilage. Self-assembling meniscus-shaped constructs engineered from a co-culture of articular chondrocytes and either meniscus, tendon, or ligament cells were cultured for 4 weeks with TGF-β1 in serum-free media. After culture, constructs were assessed for their mechanical properties, histological staining, gross appearance, and biochemical composition including cross-link content. Correlations were performed to evaluate relationships between biochemical content and mechanical properties. In terms of mechanical properties as well as biochemical content, constructs engineered using tenocytes and ligament fibrocytes were found to be equivalent or superior to constructs engineered using meniscus cells. Furthermore, cross-link content was found to be correlated with engineered tissue tensile properties. Tenocytes and ligament fibrocytes represent viable cell sources for engineering meniscus fibrocartilage using the self-assembling process. Due to greater cross-link content, fibrocartilage engineered with tenocytes and ligament fibrocytes may maintain greater tensile properties than fibrocartilage engineered with meniscus cells. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Tendon and ligament as novel cell sources for engineering the knee meniscus

PubMed Central

Hadidi, Pasha; Paschos, Nikolaos K.; Huang, Brian J.; Aryaei, Ashkan; Hu, Jerry C.; Athanasiou, Kyriacos A.

2016-01-01

Objective The application of cell-based therapies in regenerative medicine is hindered by the difficulty of acquiring adequate numbers of competent cells. For the knee meniscus in particular, this may be solved by harvesting tissue from neighboring tendons and ligaments. In this study, we have investigated the potential of cells from tendon and ligament, as compared to meniscus cells, to engineer scaffold-free self-assembling fibrocartilage. Method Self-assembling meniscus-shaped constructs engineered from a co-culture of articular chondrocytes and either meniscus, tendon, or ligament cells were cultured for 4 weeks with TGF-β1 in serum-free media. After culture, constructs were assessed for their mechanical properties, histological staining, gross appearance, and biochemical composition including cross-link content. Correlations were performed to evaluate relationships between biochemical content and mechanical properties. Results In terms of mechanical properties as well as biochemical content, constructs engineered using tenocytes and ligament fibrocytes were found to be equivalent or superior to constructs engineered using meniscus cells. Furthermore, cross-link content was found to be correlated with engineered tissue tensile properties. Conclusion Tenocytes and ligament fibrocytes represent viable cell sources for engineering meniscus fibrocartilage using the self-assembling process. Due to greater cross-link content, fibrocartilage engineered with tenocytes and ligament fibrocytes may maintain greater tensile properties than fibrocartilage engineered with meniscus cells. PMID:27473559

Scaffolds for Controlled Release of Cartilage Growth Factors.

PubMed

Morille, Marie; Venier-Julienne, Marie-Claire; Montero-Menei, Claudia N

2015-01-01

In recent years, cell-based therapies using adult stem cells have attracted considerable interest in regenerative medicine. A tissue-engineered construct for cartilage repair should provide a support for the cell and allow sustained in situ delivery of bioactive factors capable of inducing cell differentiation into chondrocytes. Pharmacologically active microcarriers (PAMs), made of biodegradable and biocompatible poly (D,L-lactide-co-glycolide acid) (PLGA), are a unique system which combines these properties in an adaptable and simple microdevice. This device relies on nanoprecipitation of proteins encapsulated in polymeric microspheres with a solid in oil in water emulsion-solvent evaporation process, and their subsequent coating with extracellular matrix protein molecules. Here, we describe their preparation process, and some of their characterization methods for an application in cartilage tissue engineering.

Nucleic acid aptamers: an emerging frontier in cancer therapy.

PubMed

Zhu, Guizhi; Ye, Mao; Donovan, Michael J; Song, Erqun; Zhao, Zilong; Tan, Weihong

2012-11-04

The last two decades have witnessed the development and application of nucleic acid aptamers in a variety of fields, including target analysis, disease therapy, and molecular and cellular engineering. The efficient and widely applicable aptamer selection, reproducible chemical synthesis and modification, generally impressive target binding selectivity and affinity, relatively rapid tissue penetration, low immunogenicity, and rapid systemic clearance make aptamers ideal recognition elements for use as therapeutics or for in vivo delivery of therapeutics. In this feature article, we discuss the development and biomedical application of nucleic acid aptamers, with emphasis on cancer cell aptamer isolation, targeted cancer therapy, oncology biomarker identification and drug discovery.

Role of adipose-derived stem cells in wound healing.

PubMed

Hassan, Waqar Ul; Greiser, Udo; Wang, Wenxin

2014-01-01

Impaired wound healing remains a challenge to date and causes debilitating effects with tremendous suffering. Recent advances in tissue engineering approaches in the area of cell therapy have provided promising treatment options to meet the challenges of impaired skin wound healing such as diabetic foot ulcers. Over the last few years, stem cell therapy has emerged as a novel therapeutic approach for various diseases including wound repair and tissue regeneration. Several different types of stem cells have been studied in both preclinical and clinical settings such as bone marrow-derived stem cells, adipose-derived stem cells (ASCs), circulating angiogenic cells (e.g., endothelial progenitor cells), human dermal fibroblasts, and keratinocytes for wound healing. Adipose tissue is an abundant source of mesenchymal stem cells, which have shown an improved outcome in wound healing studies. ASCs are pluripotent stem cells with the ability to differentiate into different lineages and to secrete paracrine factors initiating tissue regeneration process. The abundant supply of fat tissue, ease of isolation, extensive proliferative capacities ex vivo, and their ability to secrete pro-angiogenic growth factors make them an ideal cell type to use in therapies for the treatment of nonhealing wounds. In this review, we look at the pathogenesis of chronic wounds, role of stem cells in wound healing, and more specifically look at the role of ASCs, their mechanism of action and their safety profile in wound repair and tissue regeneration. © 2014 by the Wound Healing Society.

Dental pulp stem cells in regenerative dentistry.

PubMed

Casagrande, Luciano; Cordeiro, Mabel M; Nör, Silvia A; Nör, Jacques E

2011-01-01

Stem cells constitute the source of differentiated cells for the generation of tissues during development, and for regeneration of tissues that are diseased or injured postnatally. In recent years, stem cell research has grown exponentially owing to the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that span from Alzheimer's disease to cardiac ischemia to bone or tooth loss. Growing evidence demonstrates that stem cells are primarily found in niches and that certain tissues contain more stem cells than others. Among these tissues, the dental pulp is considered a rich source of mesenchymal stem cells that are suitable for tissue engineering applications. It is known that dental pulp stem cells have the potential to differentiate into several cell types, including odontoblasts, neural progenitors, osteoblasts, chondrocytes, and adipocytes. The dental pulp stem cells are highly proliferative. This characteristic facilitates ex vivo expansion and enhances the translational potential of these cells. Notably, the dental pulp is arguably the most accessible source of postnatal stem cells. Collectively, the multipotency, high proliferation rates, and accessibility make the dental pulp an attractive source of mesenchymal stem cells for tissue regeneration. This review discusses fundamental concepts of stem cell biology and tissue engineering within the context of regenerative dentistry.

Placental-derived stem cells: Culture, differentiation and challenges

PubMed Central

Oliveira, Maira S; Barreto-Filho, João B

2015-01-01

Stem cell therapy is a promising approach to clinical healing in several diseases. A great variety of tissues (bone marrow, adipose tissue, and placenta) are potentially sources of stem cells. Placenta-derived stem cells (p-SCs) are in between embryonic and mesenchymal stem cells, sharing characteristics with both, such as non-carcinogenic status and property to differentiate in all embryonic germ layers. Moreover, their use is not ethically restricted as fetal membranes are considered medical waste after birth. In this context, the present review will be focused on the biological properties, culture and potential cell therapy uses of placental-derived stem cells. Immunophenotype characterization, mainly for surface marker expression, and basic principles of p-SC isolation and culture (mechanical separation or enzymatic digestion of the tissues, the most used culture media, cell plating conditions) will be presented. In addition, some preclinical studies that were performed in different medical areas will be cited, focusing on neurological, liver, pancreatic, heart, muscle, pulmonary, and bone diseases and also in tissue engineering field. Finally, some challenges for stem cell therapy applications will be highlighted. The understanding of the mechanisms involved in the p-SCs differentiation and the achievement of pure cell populations (after differentiation) are key points that must be clarified before bringing the preclinical studies, performed at the bench, to the medical practice. PMID:26029347

Similar Properties of Chondrocytes from Osteoarthritis Joints and Mesenchymal Stem Cells from Healthy Donors for Tissue Engineering of Articular Cartilage

PubMed Central

Fernandes, Amilton M.; Herlofsen, Sarah R.; Karlsen, Tommy A.; Küchler, Axel M.; Fløisand, Yngvar; Brinchmann, Jan E.

2013-01-01

Lesions of hyaline cartilage do not heal spontaneously, and represent a therapeutic challenge. In vitro engineering of articular cartilage using cells and biomaterials may prove to be the best solution. Patients with osteoarthritis (OA) may require tissue engineered cartilage therapy. Chondrocytes obtained from OA joints are thought to be involved in the disease process, and thus to be of insufficient quality to be used for repair strategies. Bone marrow (BM) derived mesenchymal stem cells (MSCs) from healthy donors may represent an alternative cell source. We have isolated chondrocytes from OA joints, performed cell culture expansion and tissue engineering of cartilage using a disc-shaped alginate scaffold and chondrogenic differentiation medium. We performed real-time reverse transcriptase quantitative PCR and fluorescence immunohistochemistry to evaluate mRNA and protein expression for a range of molecules involved in chondrogenesis and OA pathogenesis. Results were compared with those obtained by using BM-MSCs in an identical tissue engineering strategy. Finally the two populations were compared using genome-wide mRNA arrays. At three weeks of chondrogenic differentiation we found high and similar levels of hyaline cartilage-specific type II collagen and fibrocartilage-specific type I collagen mRNA and protein in discs containing OA and BM-MSC derived chondrocytes. Aggrecan, the dominant proteoglycan in hyaline cartilage, was more abundantly distributed in the OA chondrocyte extracellular matrix. OA chondrocytes expressed higher mRNA levels also of other hyaline extracellular matrix components. Surprisingly BM-MSC derived chondrocytes expressed higher mRNA levels of OA markers such as COL10A1, SSP1 (osteopontin), ALPL, BMP2, VEGFA, PTGES, IHH, and WNT genes, but lower levels of MMP3 and S100A4. Based on the results presented here, OA chondrocytes may be suitable for tissue engineering of articular cartilage. PMID:23671648

Computer-aided design of microvasculature systems for use in vascular scaffold production.

PubMed

Mondy, William Lafayette; Cameron, Don; Timmermans, Jean-Pierre; De Clerck, Nora; Sasov, Alexander; Casteleyn, Christophe; Piegl, Les A

2009-09-01

In vitro biomedical engineering of intact, functional vascular networks, which include capillary structures, is a prerequisite for adequate vascular scaffold production. Capillary structures are necessary since they provide the elements and compounds for the growth, function and maintenance of 3D tissue structures. Computer-aided modeling of stereolithographic (STL) micro-computer tomographic (micro-CT) 3D models is a technique that enables us to mimic the design of vascular tree systems containing capillary beds, found in tissues. In our first paper (Mondy et al 2009 Tissue Eng. at press), using micro-CT, we studied the possibility of using vascular tissues to produce data capable of aiding the design of vascular tree scaffolding, which would help in the reverse engineering of a complete vascular tree system including capillary bed structures. In this paper, we used STL models of large datasets of computer-aided design (CAD) data of vascular structures which contained capillary structures that mimic those in the dermal layers of rabbit skin. Using CAD software we created from 3D STL models a bio-CAD design for the development of capillary-containing vascular tree scaffolding for skin. This method is designed to enhance a variety of therapeutic protocols including, but not limited to, organ and tissue repair, systemic disease mediation and cell/tissue transplantation therapy. Our successful approach to in vitro vasculogenesis will allow the bioengineering of various other types of 3D tissue structures, and as such greatly expands the potential applications of biomedical engineering technology into the fields of biomedical research and medicine.

Platelet-rich fibrin: a boon in regenerative endodontics.

PubMed

Rebentish, Priyanka D; Umashetty, Girish; Kaur, Harpreet; Doizode, Trupthi; Kaslekar, Mithun; Chowdhury, Shouvik

2016-12-01

Research into regenerative dentistry has contributed momentum to the field of molecular biology. Periapical surgery aims at removing periapical pathology to achieve complete wound healing and regeneration of bone and periodontal tissue. Regenerative endodontic procedures are widely being added to the current armamentarium of pulp therapy procedures. The regenerative potential of platelets has been deliberated. Platelet-rich fibrin (PRF) is a wonderful tissue-engineering product and has recently gained much popularity due its promising results in wound healing bone induction. The features of this product are an attribute of platelets which, after cellular interactions, release growth factors and have shown application in diverse disciplines of dentistry. This paper is intended to shed light onto the various prospects of PRF and to provide clinical insight into regenerative endodontic therapy.

Biologic properties of endothelial progenitor cells and their potential for cell therapy.

PubMed

Young, Pampee P; Vaughan, Douglas E; Hatzopoulos, Antonis K

2007-01-01

Recent studies indicate that portions of ischemic and tumor neovasculature are derived by neovasculogenesis, whereby bone marrow (BM)-derived circulating endothelial progenitor cells (EPCs) home to sites of regenerative or malignant growth and contribute to blood vessel formation. Recent data from animal models suggest that a variety of cell types, including unfractionated BM mononuclear cells and those obtained by ex vivo expansion of human peripheral blood or enriched progenitors, can function as EPCs to promote tissue vasculogenesis, regeneration, and repair when introduced in vivo. The promising preclinical results have led to several human clinical trials using BM as a potential source of EPCs in cardiac repair as well as ongoing basic research on using EPCs in tissue engineering or as cell therapy to target tumor growth.

Polymeric nanoparticles for targeted drug delivery system for cancer therapy.

PubMed

Masood, Farha

2016-03-01

A targeted delivery system based on the polymeric nanoparticles as a drug carrier represents a marvelous avenue for cancer therapy. The pivotal characteristics of this system include biodegradability, biocompatibility, non-toxicity, prolonged circulation and a wide payload spectrum of a therapeutic agent. Other outstanding features are their distinctive size and shape properties for tissue penetration via an active and passive targeting, specific cellular/subcellular trafficking pathways and facile control of cargo release by sophisticated material engineering. In this review, the current implications of encapsulation of anticancer agents within polyhydroxyalkanoates, poly-(lactic-co-glycolic acid) and cyclodextrin based nanoparticles to precisely target the tumor site, i.e., cell, tissue and organ are highlighted. Furthermore, the promising perspectives in this emerging field are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

Hierarchical Design of Tissue Regenerative Constructs.

PubMed

Rose, Jonas C; De Laporte, Laura

2018-03-01

The worldwide shortage of organs fosters significant advancements in regenerative therapies. Tissue engineering and regeneration aim to supply or repair organs or tissues by combining material scaffolds, biochemical signals, and cells. The greatest challenge entails the creation of a suitable implantable or injectable 3D macroenvironment and microenvironment to allow for ex vivo or in vivo cell-induced tissue formation. This review gives an overview of the essential components of tissue regenerating scaffolds, ranging from the molecular to the macroscopic scale in a hierarchical manner. Further, this review elaborates about recent pivotal technologies, such as photopatterning, electrospinning, 3D bioprinting, or the assembly of micrometer-scale building blocks, which enable the incorporation of local heterogeneities, similar to most native extracellular matrices. These methods are applied to mimic a vast number of different tissues, including cartilage, bone, nerves, muscle, heart, and blood vessels. Despite the tremendous progress that has been made in the last decade, it remains a hurdle to build biomaterial constructs in vitro or in vivo with a native-like structure and architecture, including spatiotemporal control of biofunctional domains and mechanical properties. New chemistries and assembly methods in water will be crucial to develop therapies that are clinically translatable and can evolve into organized and functional tissues. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Engineering a functional three-dimensional human cardiac tissue model for drug toxicity screening.

PubMed

Lu, Hong Fang; Leong, Meng Fatt; Lim, Tze Chiun; Chua, Ying Ping; Lim, Jia Kai; Du, Chan; Wan, Andrew C A

2017-05-11

Cardiotoxicity is one of the major reasons for clinical drug attrition. In vitro tissue models that can provide efficient and accurate drug toxicity screening are highly desired for preclinical drug development and personalized therapy. Here, we report the fabrication and characterization of a human cardiac tissue model for high throughput drug toxicity studies. Cardiac tissues were fabricated via cellular self-assembly of human transgene-free induced pluripotent stem cells-derived cardiomyocytes in pre-fabricated polydimethylsiloxane molds. The formed tissue constructs expressed cardiomyocyte-specific proteins, exhibited robust production of extracellular matrix components such as laminin, collagen and fibronectin, aligned sarcomeric organization, and stable spontaneous contractions for up to 2 months. Functional characterization revealed that the cardiac cells cultured in 3D tissues exhibited higher contraction speed and rate, and displayed a significantly different drug response compared to cells cultured in age-matched 2D monolayer. A panel of clinically relevant compounds including antibiotic, antidiabetic and anticancer drugs were tested in this study. Compared to conventional viability assays, our functional contractility-based assays were more sensitive in predicting drug-induced cardiotoxic effects, demonstrating good concordance with clinical observations. Thus, our 3D cardiac tissue model shows great potential to be used for early safety evaluation in drug development and drug efficiency testing for personalized therapy.

Functionalized scaffolds to control dental pulp stem cell fate

PubMed Central

Piva, Evandro; Silva, Adriana F.; Nör, Jacques E.

2014-01-01

Emerging understanding about interactions between stem cells, scaffolds and morphogenic factors has accelerated translational research in the field of dental pulp tissue engineering. Dental pulp stem cells constitute a sub-population of cells endowed with self-renewal and multipotency. Dental pulp stem cells seeded in biodegradable scaffolds and exposed to dentin-derived morphogenic signals give rise to a pulp-like tissue capable of generating new dentin. Notably, dentin-derived proteins are sufficient to induce dental pulp stem cell differentiation into odontoblasts. Ongoing work is focused on developing ways of mobilizing dentin-derived proteins and disinfecting the root canal of necrotic teeth without compromising the morphogenic potential of these signaling molecules. On the other hand, dentin by itself does not appear to be capable of inducing endothelial differentiation of dental pulp stem cells, despite the well known presence of angiogenic factors in dentin. This is particularly relevant in the context of dental pulp tissue engineering in full root canals, where access to blood supply is limited to the apical foramina. To address this challenge, scientists are looking at ways to use the scaffold as a controlled release device for angiogenic factors. The aim of this manuscript is to present and discuss current strategies to functionalize injectable scaffolds and customize them for dental pulp tissue engineering. The long-term goal of this work is to develop stem cell-based therapies that enable the engineering of functional dental pulps capable of generating new tubular dentin in humans. PMID:24698691

Adipose-derived stem cells and periodontal tissue engineering.

PubMed

Tobita, Morikuni; Mizuno, Hiroshi

2013-01-01

Innovative developments in the multidisciplinary field of tissue engineering have yielded various implementation strategies and the possibility of functional tissue regeneration. Technologic advances in the combination of stem cells, biomaterials, and growth factors have created unique opportunities to fabricate tissues in vivo and in vitro. The therapeutic potential of human multipotent mesenchymal stem cells (MSCs), which are harvested from bone marrow and adipose tissue, has generated increasing interest in a wide variety of biomedical disciplines. These cells can differentiate into a variety of tissue types, including bone, cartilage, fat, and nerve tissue. Adipose-derived stem cells have some advantages compared with other sources of stem cells, most notably that a large number of cells can be easily and quickly isolated from adipose tissue. In current clinical therapy for periodontal tissue regeneration, several methods have been developed and applied either alone or in combination, such as enamel matrix proteins, guided tissue regeneration, autologous/allogeneic/xenogeneic bone grafts, and growth factors. However, there are various limitations and shortcomings for periodontal tissue regeneration using current methods. Recently, periodontal tissue regeneration using MSCs has been examined in some animal models. This method has potential in the regeneration of functional periodontal tissues because the various secreted growth factors from MSCs might not only promote the regeneration of periodontal tissue but also encourage neovascularization of the damaged tissues. Adipose-derived stem cells are especially effective for neovascularization compared with other MSC sources. In this review, the possibility and potential of adipose-derived stem cells for regenerative medicine are introduced. Of particular interest, periodontal tissue regeneration with adipose-derived stem cells is discussed.

What We Should Know Before Using Tissue Engineering Techniques to Repair Injured Tendons: A Developmental Biology Perspective

PubMed Central

Liu, Chia-Feng; Aschbacher-Smith, Lindsey; Barthelery, Nicolas J.; Dyment, Nathaniel; Butler, David

2011-01-01

Tendons connect muscles to bones, and serve as the transmitters of force that allow all the movements of the body. Tenocytes are the basic cellular units of tendons, and produce the collagens that form the hierarchical fiber system of the tendon. Tendon injuries are common, and difficult to repair, particularly in the case of the insertion of tendon into bone. Successful attempts at cell-based repair therapies will require an understanding of the normal development of tendon tissues, including their differentiated regions such as the fibrous mid-section and fibrocartilaginous insertion site. Many genes are known to be involved in the formation of tendon. However, their functional roles in tendon development have not been fully characterized. Tissue engineers have attempted to generate functional tendon tissue in vitro. However, a lack of knowledge of normal tendon development has hampered these efforts. Here we review studies focusing on the developmental mechanisms of tendon development, and discuss the potential applications of a molecular understanding of tendon development to the treatment of tendon injuries. PMID:21314435

Current Technologies Based on the Knowledge of the Stem Cells Microenvironments.

PubMed

Mawad, Damia; Figtree, Gemma; Gentile, Carmine

2017-01-01

The stem cell microenvironment or niche plays a critical role in the regulation of survival, differentiation and behavior of stem cells and their progenies. Recapitulating each aspect of the stem cell niche is therefore essential for their optimal use in in vitro studies and in vivo as future therapeutics in humans. Engineering of optimal conditions for three-dimensional stem cell culture includes multiple transient and dynamic physiological stimuli, such as blood flow and tissue stiffness. Bioprinting and microfluidics technologies, including organs-on-a-chip, are among the most recent approaches utilized to replicate the three-dimensional stem cell niche for human tissue fabrication that allow the integration of multiple levels of tissue complexity, including blood flow. This chapter focuses on the physico-chemical and genetic cues utilized to engineer the stem cell niche and provides an overview on how both bioprinting and microfluidics technologies are improving our knowledge in this field for both disease modeling and tissue regeneration, including drug discovery and toxicity high-throughput assays and stem cell-based therapies in humans.

Monitoring tissue metabolism via time-resolved laser fluorescence

NASA Astrophysics Data System (ADS)

Maerz, Holger K.; Buchholz, Rainer; Emmrich, Frank; Fink, Frank; Geddes, Clive L.; Pfeifer, Lutz; Raabe, Ferdinand; Marx, Uwe

1999-05-01

Most assays for drug screening are monitoring the metabolism of cells by detecting the NADH content, which symbolize its metabolic activity, indirectly. Nowadays, the performance of a LASER enables us to monitor the metabolic state of mammalian cells directly and on-line by using time-resolved autofluorescence detection. Therefore, we developed in combination with tissue engineering, an assay for monitoring minor toxic effects of volatile organic compounds (VOC), which are accused of inducing Sick Building Syndrome (SBS). Furthermore, we used the Laserfluoroscope (LF) for pharmacological studies on human bone marrow in vitro with special interest in chemotherapy simulation. In cancer research and therapy, the effect of chemostatica in vitro in the so-called oncobiogram is being tested; up to now without great success. However, it showed among other things that tissue structure plays a vital role. Consequently, we succeeded in simulating a chemotherapy in vitro on human bone marrow. Furthermore, after tumor ektomy we were able to distinguish between tumoric and its surrounding healthy tissue by using the LF. With its sensitive detection of metabolic changes in tissues the LF enables a wide range of applications in biotechnology, e.g. for quality control in artificial organ engineering or biocompatability testing.

Generation and Assessment of Functional Biomaterial Scaffolds for Applications in Cardiovascular Tissue Engineering and Regenerative Medicine.

PubMed

Hinderer, Svenja; Brauchle, Eva; Schenke-Layland, Katja

2015-11-18

Current clinically applicable tissue and organ replacement therapies are limited in the field of cardiovascular regenerative medicine. The available options do not regenerate damaged tissues and organs, and, in the majority of the cases, show insufficient restoration of tissue function. To date, anticoagulant drug-free heart valve replacements or growing valves for pediatric patients, hemocompatible and thrombus-free vascular substitutes that are smaller than 6 mm, and stem cell-recruiting delivery systems that induce myocardial regeneration are still only visions of researchers and medical professionals worldwide and far from being the standard of clinical treatment. The design of functional off-the-shelf biomaterials as well as automatable and up-scalable biomaterial processing methods are the focus of current research endeavors and of great interest for fields of tissue engineering and regenerative medicine. Here, various approaches that aim to overcome the current limitations are reviewed, focusing on biomaterials design and generation methods for myocardium, heart valves, and blood vessels. Furthermore, novel contact- and marker-free biomaterial and extracellular matrix assessment methods are highlighted. © 2015 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Scaffold Translation: Barriers Between Concept and Clinic

PubMed Central

Murphy, William L.

2011-01-01

Translation of scaffold-based bone tissue engineering (BTE) therapies to clinical use remains, bluntly, a failure. This dearth of translated tissue engineering therapies (including scaffolds) remains despite 25 years of research, research funding totaling hundreds of millions of dollars, over 12,000 papers on BTE and over 2000 papers on BTE scaffolds alone in the past 10 years (PubMed search). Enabling scaffold translation requires first an understanding of the challenges, and second, addressing the complete range of these challenges. There are the obvious technical challenges of designing, manufacturing, and functionalizing scaffolds to fill the Form, Fixation, Function, and Formation needs of bone defect repair. However, these technical solutions should be targeted to specific clinical indications (e.g., mandibular defects, spine fusion, long bone defects, etc.). Further, technical solutions should also address business challenges, including the need to obtain regulatory approval, meet specific market needs, and obtain private investment to develop products, again for specific clinical indications. Finally, these business and technical challenges present a much different model than the typical research paradigm, presenting the field with philosophical challenges in terms of publishing and funding priorities that should be addressed as well. In this article, we review in detail the technical, business, and philosophical barriers of translating scaffolds from Concept to Clinic. We argue that envisioning and engineering scaffolds as modular systems with a sliding scale of complexity offers the best path to addressing these translational challenges. PMID:21902613

Application of eGFP to label human periodontal ligament stem cells in periodontal tissue engineering.

PubMed

Wen, Yong; Lan, Jing; Huang, Haiyun; Yu, Meijiao; Cui, Jun; Liang, Jin; Jiang, Baoqi; Xu, Xin

2012-09-01

To establish human periodontal ligament stem cells (hPDLSC) with high and stable expression of enhanced green fluorescent protein (eGFP) and to obtain an ideal vector expression system that suitable for gene therapy in periodontal tissue engineering. hPDLSCs were transfected with eGFP for 48h via different MOI (25, 50, 100, 200 and 400) by lentiviral vector, the transfection efficiency was evaluated by fluorescent microscopy and flow cytometry, and transfected hPDLSCs proliferation was evaluated by MTT. Pluripotent, differentiation capacity and ALP expression status were determined further. Osteoblast-associated genes expressions for osteogenesis were evaluated by quantitative-PCR. In addition, rat molar periodontal fenestration defect model was used for evaluating periodontal tissue engineering. The transfection efficiency after 48h were 44.7%, 60.9%, 71.7%, 85.8%, and 86.9% respectively. There was no significant effect of transfection (at different MOI levels of 25, 50, 100, and 200) on the proliferation of hPDLSCs (designated as eGFP-hPDLSCs) compared with hPDLSCs (P>0.05). However, proliferation of eGFP hPDLSCs at MOI 400 became slower (P<0.05). Both eGFP hPDLSCs and hPDLSCs were able to differentiate into osteocytes and adipocytes under certain conditioned media. At 7 days, expression levels of COL-1, RUNX2 in hPDLSCS were higher than those in eGFP hPDLSCs (P<0.05); expression levels of ALP and OPN in eGFP hPDLSCs were similar to those in hPDLSCs (P>0.05). Newly regenerated bone formation was observed in the defect model used. Among the transfection conditions, 48h transfection at MOI 200 is optimal for labelling hPDLSCs with eGFP in a lentiviral vector. There is no change in capability of the eGFP hPDLSCs osteogenesis. The lentiviral vector with eGFP is an appropriate expression vector system and hPDLSCs are ideal seeding cells for gene therapy in periodontal tissue engineering. Copyright © 2012 Elsevier Ltd. All rights reserved.

Genetic engineering of somatic cells to study and improve cardiac function.

PubMed

Kirkton, Robert D; Bursac, Nenad

2012-11-01

To demonstrate the utility of genetically engineered excitable cells for studies of basic electrophysiology and cardiac cell therapy. 'Zig-zag' networks of neonatal rat ventricular myocytes (NRVMs) were micropatterned onto thin elastomeric films to mimic the slow action potential (AP) conduction found in fibrotic myocardium. Addition of genetically engineered excitable human embryonic kidney cells (HEK-293 cells) ('Ex-293' cells stably expressing Kir2.1, Na(v)1.5, and Cx43 channels) increased both cardiac conduction velocity by 370% and twitch force amplitude by 64%. Furthermore, we stably expressed mutant Na(v)1.5 [A1924T (fast sodium channel mutant (substitution of alanine by threonine at amino acid 1924)] channels with hyperpolarized steady-state activation and showed that, despite a 71.6% reduction in peak I(Na), these cells propagated APs at the same velocity as the wild-type Na(v)1.5-expressing Ex-293 cells. Stable expression of Ca(v)3.3 (T-type voltage-gated calcium) channels in Ex-293 cells (to generate an 'ExCa-293' line) significantly increased their AP duration and reduced repolarization gradients in cocultures of these cells and NRVMs. Additional expression of an optogenetic construct [ChIEF (light-gated Channelrhodopsin mutant)]enabled light-based control of AP firing in ExCa-293 cells. We show that, despite being non-contractile, genetically engineered excitable cells can significantly improve both electrical and mechanical function of engineered cardiac tissues in vitro. We further demonstrate the utility of engineered cells for tissue-level studies of basic electrophysiology and cardiac channelopathies. In the future, this novel platform could be utilized in the high-throughput design of new genetically encoded indicators of cell electrical function, validation, and improvement of computer models of AP conduction, and development of novel engineered somatic cell therapies for the treatment of cardiac infarction and arrhythmias.

How controlled release technology can aid gene delivery.

PubMed

Jo, Jun-Ichiro; Tabata, Yasuhiko

2015-01-01

Many types of gene delivery systems have been developed to enhance the level of gene expression. Controlled release technology is a feasible gene delivery system which enables genes to extend the expression duration by maintaining and releasing them at the injection site in a controlled manner. This technology can reduce the adverse effects by the bolus dose administration and avoid the repeated administration. Biodegradable biomaterials are useful as materials for the controlled release-based gene delivery technology and various biodegradable biomaterials have been developed. Controlled release-based gene delivery plays a critical role in a conventional gene therapy and genetic engineering. In the gene therapy, the therapeutic gene is released from biodegradable biomaterial matrices around the tissue to be treated. On the other hand, the intracellular controlled release of gene from the sub-micro-sized matrices is required for genetic engineering. Genetic engineering is feasible for cell transplantation as well as research of stem cells biology and medicine. DNA hydrogel containing a sequence of therapeutic gene and the exosome including the individual specific nucleic acids may become candidates for controlled release carriers. Technologies to deliver genes to cell aggregates will play an important role in the promotion of regenerative research and therapy.

Stem Cell Differentiation Toward the Myogenic Lineage for Muscle Tissue Regeneration: A Focus on Muscular Dystrophy.

PubMed

Ostrovidov, Serge; Shi, Xuetao; Sadeghian, Ramin Banan; Salehi, Sahar; Fujie, Toshinori; Bae, Hojae; Ramalingam, Murugan; Khademhosseini, Ali

2015-12-01

Skeletal muscle tissue engineering is one of the important ways for regenerating functionally defective muscles. Among the myopathies, the Duchenne muscular dystrophy (DMD) is a progressive disease due to mutations of the dystrophin gene leading to progressive myofiber degeneration with severe symptoms. Although current therapies in muscular dystrophy are still very challenging, important progress has been made in materials science and in cellular technologies with the use of stem cells. It is therefore useful to review these advances and the results obtained in a clinical point of view. This article focuses on the differentiation of stem cells into myoblasts, and their application in muscular dystrophy. After an overview of the different stem cells that can be induced to differentiate into the myogenic lineage, we introduce scaffolding materials used for muscular tissue engineering. We then described some widely used methods to differentiate different types of stem cell into myoblasts. We highlight recent insights obtained in therapies for muscular dystrophy. Finally, we conclude with a discussion on stem cell technology. We discussed in parallel the benefits brought by the evolution of the materials and by the expansion of cell sources which can differentiate into myoblasts. We also discussed on future challenges for clinical applications and how to accelerate the translation from the research to the clinic in the frame of DMD.

Drug delivery, cell-based therapies, and tissue engineering approaches for spinal cord injury.

PubMed

Kabu, Shushi; Gao, Yue; Kwon, Brian K; Labhasetwar, Vinod

2015-12-10

Spinal cord injury (SCI) results in devastating neurological and pathological consequences, causing major dysfunction to the motor, sensory, and autonomic systems. The primary traumatic injury to the spinal cord triggers a cascade of acute and chronic degenerative events, leading to further secondary injury. Many therapeutic strategies have been developed to potentially intervene in these progressive neurodegenerative events and minimize secondary damage to the spinal cord. Additionally, significant efforts have been directed toward regenerative therapies that may facilitate neuronal repair and establish connectivity across the injury site. Despite the promise that these approaches have shown in preclinical animal models of SCI, challenges with respect to successful clinical translation still remain. The factors that could have contributed to failure include important biologic and physiologic differences between the preclinical models and the human condition, study designs that do not mirror clinical reality, discrepancies in dosing and the timing of therapeutic interventions, and dose-limiting toxicity. With a better understanding of the pathobiology of events following acute SCI, developing integrated approaches aimed at preventing secondary damage and also facilitating neuroregenerative recovery is possible and hopefully will lead to effective treatments for this devastating injury. The focus of this review is to highlight the progress that has been made in drug therapies and delivery systems, and also cell-based and tissue engineering approaches for SCI. Copyright © 2015 Elsevier B.V. All rights reserved.

Biomaterials for Craniofacial Bone Engineering

PubMed Central

Tevlin, R.; McArdle, A.; Atashroo, D.; Walmsley, G.G.; Senarath-Yapa, K.; Zielins, E.R.; Paik, K.J.; Longaker, M.T.; Wan, D.C.

2014-01-01

Conditions such as congenital anomalies, cancers, and trauma can all result in devastating deficits of bone in the craniofacial skeleton. This can lead to significant alteration in function and appearance that may have significant implications for patients. In addition, large bone defects in this area can pose serious clinical dilemmas, which prove difficult to remedy, even with current gold standard surgical treatments. The craniofacial skeleton is complex and serves important functional demands. The necessity to develop new approaches for craniofacial reconstruction arises from the fact that traditional therapeutic modalities, such as autologous bone grafting, present myriad limitations and carry with them the potential for significant complications. While the optimal bone construct for tissue regeneration remains to be elucidated, much progress has been made in the past decade. Advances in tissue engineering have led to innovative scaffold design, complemented by progress in the understanding of stem cell–based therapy and growth factor enhancement of the healing cascade. This review focuses on the role of biomaterials for craniofacial bone engineering, highlighting key advances in scaffold design and development. PMID:25139365

Engineering cells with intracellular agent–loaded microparticles to control cell phenotype

PubMed Central

Ankrum, James A; Miranda, Oscar R; Ng, Kelvin S; Sarkar, Debanjan; Xu, Chenjie; Karp, Jeffrey M

2014-01-01

Cell therapies enable unprecedented treatment options to replace tissues, destroy tumors and facilitate regeneration. The greatest challenge facing cell therapy is the inability to control the fate and function of cells after transplantation. We have developed an approach to control cell phenotype in vitro and after transplantation by engineering cells with intracellular depots that continuously release phenotype-altering agents for days to weeks. The platform enables control of cells’ secretome, viability, proliferation and differentiation, and the platform can be used to deliver drugs or other factors (e.g., dexamethasone, rhodamine and iron oxide) to the cell’s microenvironment. The preparation, efficient internalization and intracellular stabilization of ~1-μm drug-loaded microparticles are critical for establishing sustained control of cell phenotype. Herein we provide a protocol to generate and characterize micrometer-sized agent-doped poly(lactic-co-glycolic) acid (PLGA) particles by using a single-emulsion evaporation technique (7 h), to uniformly engineer cultured cells (15 h), to confirm particle internalization and to troubleshoot commonly experienced obstacles. PMID:24407352

Engineering retinal progenitor cell and scrollable poly(glycerol-sebacate) composites for expansion and subretinal transplantation

PubMed Central

Redenti, Stephen; Neeley, William L.; Rompani, Santiago; Saigal, Sunita; Yang, Jing; Klassen, Henry; Langer, Robert; Young, Michael J.

2014-01-01

Retinal degenerations cause permanent visual loss and affect millions world-wide. Presently, a novel treatment highlights the potential of using biodegradable polymer scaffolds to induce differentiation and deliver retinal progenitor cells for cell replacement therapy. In this study, we engineered and analyzed a micro-fabricated polymer, poly(glycerol sebacate) (PGS) scaffold, whose useful properties include biocompatibility, elasticity, porosity, and a microtopology conducive to mouse retinal progenitor cell (mRPC) differentiation. In vitro proliferation assays revealed that PGS held up to 86,610 (±9993) mRPCs per square millimeter, which were retained through simulated transplantations. mRPCs adherent to PGS differentiated toward mature phenotypes as evidenced by changes in mRNA, protein levels, and enhanced sensitivity to glutamate. Transplanted composites demonstrated long-term mRPC survival and migrated cells exhibited mature marker expression in host retina. These results suggest that combining mRPCs with PGS scaffolds for subretinal transplantation is a practical strategy for advancing retinal tissue engineering as a restorative therapy. PMID:19361860

Bioprinting: an assessment based on manufacturing readiness levels.

PubMed

Wu, Changsheng; Wang, Ben; Zhang, Chuck; Wysk, Richard A; Chen, Yi-Wen

2017-05-01

Over the last decade, bioprinting has emerged as a promising technology in the fields of tissue engineering and regenerative medicine. With recent advances in additive manufacturing, bioprinting is poised to provide patient-specific therapies and new approaches for tissue and organ studies, drug discoveries and even food manufacturing. Manufacturing Readiness Level (MRL) is a method that has been applied to assess manufacturing maturity and to identify risks and gaps in technology-manufacturing transitions. Technology Readiness Level (TRL) is used to evaluate the maturity of a technology. This paper reviews recent advances in bioprinting following the MRL scheme and addresses corresponding MRL levels of engineering challenges and gaps associated with the translation of bioprinting from lab-bench experiments to ultimate full-scale manufacturing of tissues and organs. According to our step-by-step TRL and MRL assessment, after years of rigorous investigation by the biotechnology community, bioprinting is on the cusp of entering the translational phase where laboratory research practices can be scaled up into manufacturing products specifically designed for individual patients.

Research highlights: Microtechnologies for engineering the cellular environment.

PubMed

Tseng, Peter; Kunze, Anja; Kittur, Harsha; Di Carlo, Dino

2014-04-07

In this issue we highlight recent microtechnology-enabled approaches to control the physical and biomolecular environment around cells: (1) developing micropatterned surfaces to quantify cell affinity choices between two adhesive patterns, (2) controlling topographical cues to align cells and improve reprogramming to a pluripotent state, and (3) controlling gradients of biomolecules to maintain pluripotency in embryonic stem cells. Quantitative readouts of cell-surface affinity in environments with several cues should open up avenues in tissue engineering where self-assembly of complex multi-cellular structures is possible by precisely engineering relative adhesive cues in three dimensional constructs. Methods of simple and local epigenetic modification of chromatin structure with microtopography and biomolecular gradients should also be of use in regenerative medicine, as well as in high-throughput quantitative analysis of external signals that impact and can be used to control cells. Overall, approaches to engineer the cellular environment will continue to be an area of further growth in the microfluidic and lab on a chip community, as the scale of the technologies seamlessly matches that of biological systems. However, because of regulations and other complexities with tissue engineered therapies, these micro-engineering approaches will likely first impact organ-on-a-chip technologies that are poised to improve drug discovery pipelines.

Use of Pig as a Model for Mesenchymal Stem Cell Therapies for Bone Regeneration.

PubMed

Rubessa, Marcello; Polkoff, Kathryn; Bionaz, Massimo; Monaco, Elisa; Milner, Derek J; Holllister, Scott J; Goldwasser, Michael S; Wheeler, Matthew B

2017-10-02

Bone is a plastic tissue with a large healing capability. However, extensive bone loss due to disease or trauma requires extreme therapy such as bone grafting or tissue-engineering applications. Presently, bone grafting is the gold standard for bone repair, but presents serious limitations including donor site morbidity, rejection, and limited tissue regeneration. The use of stem cells appears to be a means to overcome such limitations. Bone marrow mesenchymal stem cells (BMSC) have been the choice thus far for stem cell therapy for bone regeneration. However, adipose-derived stem cells (ASC) have similar immunophenotype, morphology, multilineage potential, and transcriptome compared to BMSC, and both types have demonstrated extensive osteogenic capacity both in vitro and in vivo in several species. The use of scaffolds in combination with stem cells and growth factors provides a valuable tool for guided bone regeneration, especially for complex anatomic defects. Before translation to human medicine, regenerative strategies must be developed in animal models to improve effectiveness and efficiency. The pig presents as a useful model due to similar macro- and microanatomy and favorable logistics of use. This review examines data that provides strong support for the clinical translation of the pig model for bone regeneration.

Hydrogels and Cell Based Therapies in Spinal Cord Injury Regeneration

PubMed Central

Assunção-Silva, Rita C.; Gomes, Eduardo D.; Silva, Nuno A.; Salgado, António J.

2015-01-01

Spinal cord injury (SCI) is a central nervous system- (CNS-) related disorder for which there is yet no successful treatment. Within the past several years, cell-based therapies have been explored for SCI repair, including the use of pluripotent human stem cells, and a number of adult-derived stem and mature cells such as mesenchymal stem cells, olfactory ensheathing cells, and Schwann cells. Although promising, cell transplantation is often overturned by the poor cell survival in the treatment of spinal cord injuries. Alternatively, the therapeutic role of different cells has been used in tissue engineering approaches by engrafting cells with biomaterials. The latter have the advantages of physically mimicking the CNS tissue, while promoting a more permissive environment for cell survival, growth, and differentiation. The roles of both cell- and biomaterial-based therapies as single therapeutic approaches for SCI repair will be discussed in this review. Moreover, as the multifactorial inhibitory environment of a SCI suggests that combinatorial approaches would be more effective, the importance of using biomaterials as cell carriers will be herein highlighted, as well as the recent advances and achievements of these promising tools for neural tissue regeneration. PMID:26124844

Stem Cells in Skin Regeneration, Wound Healing, and Their Clinical Applications

PubMed Central

Ojeh, Nkemcho; Pastar, Irena; Tomic-Canic, Marjana; Stojadinovic, Olivera

2015-01-01

The skin is the largest organ of the body and has an array of functions. Skin compartments, epidermis, and hair follicles house stem cells that are indispensable for skin homeostasis and regeneration. These stem cells also contribute to wound repair, resulting in restoration of tissue integrity and function of damaged tissue. Unsuccessful wound healing processes often lead to non-healing wounds. Chronic wounds are caused by depletion of stem cells and a variety of other cellular and molecular mechanisms, many of which are still poorly understood. Current chronic wound therapies are limited, so the search to develop better therapeutic strategies is ongoing. Adult stem cells are gaining recognition as potential candidates for numerous skin pathologies. In this review, we will discuss epidermal and other stem cells present in the skin, and highlight some of the therapeutic applications of epidermal stem cells and other adult stem cells as tools for cell/scaffold-based therapies for non-healing wounds and other skin disorders. We will also discuss emerging concepts and offer some perspectives on how skin tissue-engineered products can be optimized to provide efficacious therapy in cutaneous repair and regeneration. PMID:26512657

Stem Cells in Skin Regeneration, Wound Healing, and Their Clinical Applications.

PubMed

Ojeh, Nkemcho; Pastar, Irena; Tomic-Canic, Marjana; Stojadinovic, Olivera

2015-10-23

The skin is the largest organ of the body and has an array of functions. Skin compartments, epidermis, and hair follicles house stem cells that are indispensable for skin homeostasis and regeneration. These stem cells also contribute to wound repair, resulting in restoration of tissue integrity and function of damaged tissue. Unsuccessful wound healing processes often lead to non-healing wounds. Chronic wounds are caused by depletion of stem cells and a variety of other cellular and molecular mechanisms, many of which are still poorly understood. Current chronic wound therapies are limited, so the search to develop better therapeutic strategies is ongoing. Adult stem cells are gaining recognition as potential candidates for numerous skin pathologies. In this review, we will discuss epidermal and other stem cells present in the skin, and highlight some of the therapeutic applications of epidermal stem cells and other adult stem cells as tools for cell/scaffold-based therapies for non-healing wounds and other skin disorders. We will also discuss emerging concepts and offer some perspectives on how skin tissue-engineered products can be optimized to provide efficacious therapy in cutaneous repair and regeneration.

Mesenchymal stem cells: biological characteristics and potential clinical applications.

PubMed

Kassem, Moustapha

2004-01-01

Mesenchymal stem cells (MSC) are clonogenic, non-hematpoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages, for example, osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages, for example, neuronal-like cells. Several methods are currently available for isolation of the MSC based on their physical and physico-chemical characteristics, for example, adherence to plastics or other extracellular matrix components. Because of the ease of their isolation and their extensive differentiation potential, MSC are among the first stem cell types to be introduced in the clinic. Several studies have demonstrated the possible use of MSC in systemic transplantation for systemic diseases, local implantation for local tissue defects, as a vehicle for genes in gene therapy protocols or to generate transplantable tissues and organs in tissue engineering protocols. Before their widespread use in therapy, methods allowing the generation of large number of cells without affecting their differentiation potential as well as technologies that overcome immunological rejection (in case allogenic transplantation) must be developed.

Periodontal diseases.

PubMed

Kinane, Denis F; Stathopoulou, Panagiota G; Papapanou, Panos N

2017-06-22

Periodontal diseases comprise a wide range of inflammatory conditions that affect the supporting structures of the teeth (the gingiva, bone and periodontal ligament), which could lead to tooth loss and contribute to systemic inflammation. Chronic periodontitis predominantly affects adults, but aggressive periodontitis may occasionally occur in children. Periodontal disease initiation and propagation is through a dysbiosis of the commensal oral microbiota (dental plaque), which then interacts with the immune defences of the host, leading to inflammation and disease. This pathophysiological situation persists through bouts of activity and quiescence, until the affected tooth is extracted or the microbial biofilm is therapeutically removed and the inflammation subsides. The severity of the periodontal disease depends on environmental and host risk factors, both modifiable (for example, smoking) and non-modifiable (for example, genetic susceptibility). Prevention is achieved with daily self-performed oral hygiene and professional removal of the microbial biofilm on a quarterly or bi-annual basis. New treatment modalities that are actively explored include antimicrobial therapy, host modulation therapy, laser therapy and tissue engineering for tissue repair and regeneration.

Human gingiva-derived mesenchymal stem cells are superior to bone marrow-derived mesenchymal stem cells for cell therapy in regenerative medicine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomar, Geetanjali B.; Srivastava, Rupesh K.; Gupta, Navita

2010-03-12

Mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into multiple cell lineages. Presently, bone marrow is considered as a prime source of MSCs; however, there are some drawbacks and limitations in use of these MSCs for cell therapy. In this study, we demonstrate that human gingival tissue-derived MSCs have several advantages over bone marrow-derived MSCs. Gingival MSCs are easy to isolate, homogenous and proliferate faster than bone marrow MSCs without any growth factor. Importantly, gingival MSCs display stable morphology and do not loose MSC characteristic at higher passages. In addition, gingival MSCs maintain normal karyotype and telomerase activitymore » in long-term cultures, and are not tumorigenic. Thus, we reveal that human gingiva is a better source of MSCs than bone marrow, and large number of functionally competent clinical grade MSCs can be generated in short duration for cell therapy in regenerative medicine and tissue engineering.« less

Anti-EGFRvIII Chimeric Antigen Receptor-Modified T Cells for Adoptive Cell Therapy of Glioblastoma

PubMed Central

Ren, Pei-pei; Li, Ming; Li, Tian-fang; Han, Shuang-yin

2017-01-01

Glioblastoma (GBM) is one of the most devastating brain tumors with poor prognosis and high mortality. Although radical surgical treatment with subsequent radiation and chemotherapy can improve the survival, the efficacy of such regimens is insufficient because the GBM cells can spread and destroy normal brain structures. Moreover, these non-specific treatments may damage adjacent healthy brain tissue. It is thus imperative to develop novel therapies to precisely target invasive tumor cells without damaging normal tissues. Immunotherapy is a promising approach due to its capability to suppress the growth of various tumors in preclinical model and clinical trials. Adoptive cell therapy (ACT) using T cells engineered with chimeric antigen receptor (CAR) targeting an ideal molecular marker in GBM, e.g. epidermal growth factor receptor type III (EGFRvIII) has demonstrated a satisfactory efficacy in treating malignant brain tumors. Here we summarize the recent progresses in immunotherapeutic strategy using CAR-modified T cells oriented to EGFRvIII against GBM. PMID:28302023

Chondrocyte Differentiation of Human Endometrial Gland-Derived MSCs in Layered Cell Sheets

PubMed Central

Shimizu, Tatsuya; Yamato, Masayuki; Umezawa, Akihiro; Okano, Teruo

2013-01-01

Recently, regenerative medicine using engineered three-dimensional (3D) tissues has been focused. In the fields of cell therapy and regenerative medicine, mesenchymal stem cells (MSCs) are attractive autologous cell sources. While, in bioengineered tissues, a 3D environment may affect the differentiation of the stem cells, little is known regarding the effect of 3D environment on cellular differentiation. In this study, MSC differentiation in in vitro 3D tissue models was assessed by human endometrial gland-derived MSCs (hEMSCs) and cell sheet technology. hEMSC sheets were layered into cell-dense 3D tissues and were cultured on porous membranes. The tissue sections revealed that chondrocyte-like cells were found within the multilayered cell sheets even at 24 h after layering. Immunostainings of chondrospecific markers were positive within those cell sheet constructs. In addition, sulfated glycosaminoglycan accumulation within the tissues increased in proportion to the numbers of layered cell sheets. The findings suggested that a high cell density and hypoxic environment in 3D tissues by layering cell sheets might accelerate a rapid differentiation of hEMSCs into chondrocytes without the help of chondro-differentiation reagents. These tissue models using cell sheets would give new insights to stem cell differentiation in 3D environment and contribute to the future application of stem cells to cartilage regenerative therapy. PMID:24348153

Methodology of citrate-based biomaterial development and application

NASA Astrophysics Data System (ADS)

Tran, M. Richard

Biomaterials play central roles in modern strategies of regenerative medicine and tissue engineering. Attempts to find tissue-engineered solutions to cure various injuries or diseases have led to an enormous increase in the number of polymeric biomaterials over the past decade. The breadth of new materials arises from the multiplicity of anatomical locations, cell types, and mode of application, which all place application-specific requirements on the biomaterial. Unfortunately, many of the currently available biodegradable polymers are limited in their versatility to meet the wide range of requirements for tissue engineering. Therefore, a methodology of biomaterial development, which is able to address a broad spectrum of requirements, would be beneficial to the biomaterial field. This work presents a methodology of citrate-based biomaterial design and application to meet the multifaceted needs of tissue engineering. We hypothesize that (1) citric acid, a non-toxic metabolic product of the body (Krebs Cycle), can be exploited as a universal multifunctional monomer and reacted with various diols to produce a new class of soft biodegradable elastomers with the flexibility to tune the material properties of the resulting material to meet a wide range of requirements; (2) the newly developed citrate-based polymers can be used as platform biomaterials for the design of novel tissue engineering scaffolding; and (3) microengineering approaches in the form thin scaffold sheets, microchannels, and a new porogen design can be used to generate complex cell-cell and cell-microenvironment interactions to mimic tissue complexity and architecture. To test these hypotheses, we first developed a methodology of citrate-based biomaterial development through the synthesis and characterization of a family of in situ crosslinkable and urethane-doped elastomers, which are synthesized using simple, cost-effective strategies and offer a variety methods to tailor the material properties to meet the needs of a particular application. Next, we introduced a new porogen generation technique, and showed the potential application of the newly developed materials through the fabrication and characterization of scaffold sheets, multiphasic small diameter vascular grafts, and multichanneled nerve guides. Finally, the in vivo applications of citrate-based materials are exemplified through the evaluation of peripheral nerve regeneration using multichanneled guides and the ability to assist in injection-based endoscopic mucosal resection therapy. The results presented in this work show that citric acid can be utilized as a cornerstone in the development of novel biodegradable materials, and combined with microengineering approaches to produce the next generation of tissue engineering scaffolding. These enabling new biomaterials and scaffolding strategies should address many of the existing challenges in tissue engineering and advance the field as a whole.

Repair of injured articular and growth plate cartilage using mesenchymal stem cells and chondrogenic gene therapy.

PubMed

Xian, Cory J; Foster, Bruce K

2006-05-01

Injuries to the articular cartilage and growth plate are significant clinical problems due to their limited ability to regenerate themselves. Despite progress in orthopedic surgery and some success in development of chondrocyte transplantation treatment and in early tissue-engineering work, cartilage regeneration using a biological approach still remains a great challenge. In the last 15 years, researchers have made significant advances and tremendous progress in exploring the potentials of mesenchymal stem cells (MSCs) in cartilage repair. These include (a) identifying readily available sources of and devising appropriate techniques for isolation and culture expansion of MSCs that have good chondrogenic differentiation capability, (b) discovering appropriate growth factors (such as TGF-beta, IGF-I, BMPs, and FGF-2) that promote MSC chondrogenic differentiation, (c) identifying or engineering biological or artificial matrix scaffolds as carriers for MSCs and growth factors for their transplantation and defect filling. In addition, representing another new perspective for cartilage repair is the successful demonstration of gene therapy with chondrogenic growth factors or inflammatory inhibitors (either individually or in combination), either directly to the cartilage tissue or mediated through transducing and transplanting cultured chondrocytes, MSCs or other mesenchymal cells. However, despite these rapid pre-clinical advances and some success in engineering cartilage-like tissue and in repairing articular and growth plate cartilage, challenges of their clinical translation remain. To achieve clinical effectiveness, safety, and practicality of using MSCs for cartilage repair, one critical investigation will be to examine the optimal combination of MSC sources, growth factor cocktails, and supporting carrier matrixes. As more insights are acquired into the critical factors regulating MSC migration, proliferation and chondrogenic differentiation both ex vivo and in vivo, it will be possible clinically to orchestrate desirable repair of injured articular and growth plate cartilage, either by transplanting ex vivo expanded MSCs or MSCs with genetic modifications, or by mobilising endogenous MSCs from adjacent source tissues such as synovium, bone marrow, or trabecular bone.

Modulation of cardiac tissue electrophysiological properties with light-sensitive proteins.

PubMed

Nussinovitch, Udi; Shinnawi, Rami; Gepstein, Lior

2014-04-01

Optogenetics approaches, utilizing light-sensitive proteins, have emerged as unique experimental paradigms to modulate neuronal excitability. We aimed to evaluate whether a similar strategy could be used to control cardiac-tissue excitability. A combined cell and gene therapy strategy was developed in which fibroblasts were transfected to express the light-activated depolarizing channel Channelrhodopsin-2 (ChR2). Patch-clamp studies confirmed the development of a robust inward current in the engineered fibroblasts following monochromatic blue-light exposure. The engineered cells were co-cultured with neonatal rat cardiomyocytes (or human embryonic stem cell-derived cardiomyocytes) and studied using a multielectrode array mapping technique. These studies revealed the ability of the ChR2-fibroblasts to electrically couple and pace the cardiomyocyte cultures at varying frequencies in response to blue-light flashes. Activation mapping pinpointed the source of this electrical activity to the engineered cells. Similarly, diffuse seeding of the ChR2-fibroblasts allowed multisite optogenetics pacing of the co-cultures, significantly shortening their electrical activation time and synchronizing contraction. Next, optogenetics pacing in an in vitro model of conduction block allowed the resynchronization of the tissue's electrical activity. Finally, the ChR2-fibroblasts were transfected to also express the light-sensitive hyperpolarizing proton pump Archaerhodopsin-T (Arch-T). Seeding of the ChR2/ArchT-fibroblasts allowed to either optogentically pace the cultures (in response to blue-light flashes) or completely suppress the cultures' electrical activity (following continuous illumination with 624 nm monochromatic light, activating ArchT). The results of this proof-of-concept study highlight the unique potential of optogenetics for future biological pacemaking and resynchronization therapy applications and for the development of novel anti-arrhythmic strategies.

Stem cells: The Next Therapeutic Frontier

PubMed Central

Humes, H. David

2005-01-01

Cell therapy is one of the most exciting fields in translational medicine. It stands at the intersection of a variety of rapidly developing scientific disciplines: stem cell biology, immunology, tissue engineering, molecular biology, biomaterials, transplantation biology, regenerative medicine, and clinical research. Cell-based therapy may develop into a new therapeutic platform to treat a vast array of clinical disorders. Blood transfusions and bone marrow transplantation are prime examples of the successful application of cell-based therapeutics; but recent advances in cellular and molecular biology have expanded the potential applications of this approach. Although recombinant genetic engineering to produce a variety of therapeutics such as human erythropoietin and insulin has proven successful, these treatments are unable to completely correct or reverse disease states, because most common disease processes are not due to the deficiency of a single protein but develop due to alterations in the complex interactions of a variety of cell components. In these complex situations, cell-based therapy may be a more successful strategy by providing a dynamic, interactive, and individualized therapeutic approach that responds to the pathophysiological condition of the patient. In this regard, cells may provide innovative methods for drug delivery of biologics, immunotherapy, and tissue regenerative or replacement engineering (1,2). The translation of this discipline to medical practice has tremendous potential, but in many applications technological issues need to be overcome. Since many cell-based indications are already being evaluated in the clinic, the field appears to be on the threshold of a number of successes. This review will focus on our group's use of human stem/progenitor cells in the treatment of acute and chronic renal failure as extensions to the current successful renal substitution processes of hemodialysis and hemofiltration. PMID:16555613

Biomaterial design for specific cellular interactions: Role of surface functionalization and geometric features

NASA Astrophysics Data System (ADS)

Kolhar, Poornima

The areas of drug delivery and tissue engineering have experienced extraordinary growth in recent years with the application of engineering principles and their potential to support and improve the field of medicine. The tremendous progress in nanotechnology and biotechnology has lead to this explosion of research and development in biomedical applications. Biomaterials can now be engineered at a nanoscale and their specific interactions with the biological tissues can be modulated. Various design parameters are being established and researched for design of drug-delivery carriers and scaffolds to be implanted into humans. Nanoparticles made from versatile biomaterial can deliver both small-molecule drugs and various classes of bio-macromolecules, such as proteins and oligonucleotides. Similarly in the field of tissue engineering, current approaches emphasize nanoscale control of cell behavior by mimicking the natural extracellular matrix (ECM) unlike, traditional scaffolds. Drug delivery and tissue engineering are closely connected fields and both of these applications require materials with exceptional physical, chemical, biological, and biomechanical properties to provide superior therapy. In the current study the surface functionalization and the geometric features of the biomaterials has been explored. In particular, a synthetic surface for culture of human embryonic stem cells has been developed, demonstrating the importance of surface functionalization in maintaining the pluripotency of hESCs. In the second study, the geometric features of the drug delivery carriers are investigated and the polymeric nanoneedles mediated cellular permeabilization and direct cytoplasmic delivery is reported. In the third study, the combined effect of surface functionalization and geometric modification of carriers for vascular targeting is enunciated. These studies illustrate how the biomaterials can be designed to achieve various cellular behaviors and control the interactions with cells in vivo .

Tissue Engineering in Osteoarthritis: Current Status and Prospect of Mesenchymal Stem Cell Therapy.

PubMed

Im, Gun-Il

2018-04-27

Osteoarthritis (OA) is the most common form of arthritis. Over the last 20 years, attempts have been made to regenerate articular cartilage to overcome the limitations of conventional treatments. As OA is generally associated with larger and diffuse involvement of articular surfaces and alteration of joint homeostasis, a tissue engineering approach for cartilage regeneration is more difficult than in simple chondral defects. Autologous and allogeneic mesenchymal stem cells (MSCs) have rapidly emerged as investigational products for cartilage regeneration. This review outlines points to consider in MSC-based approaches for OA treatment, including allogeneic MSCs, sources of MSCs, dosages, feasibility of multiple injections, indication according to severity of OA lesion and patient age, and issues regarding implantation versus injection. We introduce possible mechanisms of action of implanted or injected MSCs as well as the immunological aspects of MSC therapy and provide a summary of clinical trials of MSCs in the treatment of OA. Given current knowledge, it is too early to draw conclusions on the ultimate effectiveness of intra-articular application of MSCs in terms of regenerative effects. Further radiological and histological data will be needed, with a larger pool of patients, before this question can be answered.

Bone regeneration: stem cell therapies and clinical studies in orthopaedics and traumatology.

PubMed

Gómez-Barrena, Enrique; Rosset, Philippe; Müller, Ingo; Giordano, Rosaria; Bunu, Carmen; Layrolle, Pierre; Konttinen, Yrjö T; Luyten, Frank P

2011-06-01

Regenerative medicine seeks to repair or replace damaged tissues or organs, with the goal to fully restore structure and function without the formation of scar tissue. Cell based therapies are promising new therapeutic approaches in regenerative medicine. By using mesenchymal stem cells, good results have been reported for bone engineering in a number of clinical studies, most of them investigator initiated trials with limited scope with respect to controls and outcome. With the implementation of a new regulatory framework for advanced therapeutic medicinal products, the stage is set to improve both the characterization of the cells and combination products, and pave the way for improved controlled and well-designed clinical trials. The incorporation of more personalized medicine approaches, including the use of biomarkers to identify the proper patients and the responders to treatment, will be contributing to progress in the field. Both translational and clinical research will move the boundaries in the field of regenerative medicine, and a coordinated effort will provide the clinical breakthroughs, particularly in the many applications of bone engineering. © 2011 The Authors Journal of Cellular and Molecular Medicine © 2011 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

Development of bioartificial myocardium using stem cells and nanobiotechnology templates.

PubMed

Chachques, Juan Carlos

2010-12-29

Cell-based regenerative therapy is undergoing experimental and clinical trials in cardiology, in order to limit the consequences of decreased contractile function and compliance of damaged ventricles following myocardial infarction. Over 1000 patients have been treated worldwide with cell-based procedures for myocardial regeneration. Cellular cardiomyoplasty seems to reduce the size and fibrosis of infarct scars, limit adverse postischemic remodelling, and improve diastolic function. The development of a bioartificial myocardium is a new challenge; in this approach, tissue-engineered procedures are associated with cell therapy. Organ decellularization for bioscaffolds fabrication is a new investigated concept. Nanomaterials are emerging as the main candidates to ensure the achievement of a proper instructive cellular niche with good drug release/administration properties. Investigating the electrophysiological properties of bioartificial myocardium is the challenging objective of future research, associating a multielectrode network to provide electrical stimulation could improve the coupling of grafted cells and scaffolds with host cardiomyocytes. In summary, until now stem cell transplantation has not achieved clear hemodynamic benefits for myocardial diseases. Supported by relevant scientific background, the development of myocardial tissue engineering may constitute a new avenue and hope for the treatment of myocardial diseases.

Stem Cells for Skeletal Muscle Tissue Engineering.

PubMed

Pantelic, Molly N; Larkin, Lisa M

2018-04-19

Volumetric muscle loss (VML) is a debilitating condition wherein muscle loss overwhelms the body's normal physiological repair mechanism. VML is particularly common among military service members who have sustained war injuries. Because of the high social and medical cost associated with VML and suboptimal current surgical treatments, there is great interest in developing better VML therapies. Skeletal muscle tissue engineering (SMTE) is a promising alternative to traditional VML surgical treatments that use autogenic tissue grafts, and rather uses isolated stem cells with myogenic potential to generate de novo skeletal muscle tissues to treat VML. Satellite cells are the native precursors to skeletal muscle tissue, and are thus the most commonly studied starting source for SMTE. However, satellite cells are difficult to isolate and purify, and it is presently unknown whether they would be a practical source in clinical SMTE applications. Alternative myogenic stem cells, including adipose-derived stem cells, bone marrow-derived mesenchymal stem cells, perivascular stem cells, umbilical cord mesenchymal stem cells, induced pluripotent stem cells, and embryonic stem cells, each have myogenic potential and have been identified as possible starting sources for SMTE, although they have yet to be studied in detail for this purpose. These alternative stem cell varieties offer unique advantages and disadvantages that are worth exploring further to advance the SMTE field toward highly functional, safe, and practical VML treatments. The following review summarizes the current state of satellite cell-based SMTE, details the properties and practical advantages of alternative myogenic stem cells, and offers guidance to tissue engineers on how alternative myogenic stem cells can be incorporated into SMTE research.

Rebuilding the Damaged Heart: Mesenchymal Stem Cells, Cell-Based Therapy, and Engineered Heart Tissue.

PubMed

Golpanian, Samuel; Wolf, Ariel; Hatzistergos, Konstantinos E; Hare, Joshua M

2016-07-01

Mesenchymal stem cells (MSCs) are broadly distributed cells that retain postnatal capacity for self-renewal and multilineage differentiation. MSCs evade immune detection, secrete an array of anti-inflammatory and anti-fibrotic mediators, and very importantly activate resident precursors. These properties form the basis for the strategy of clinical application of cell-based therapeutics for inflammatory and fibrotic conditions. In cardiovascular medicine, administration of autologous or allogeneic MSCs in patients with ischemic and nonischemic cardiomyopathy holds significant promise. Numerous preclinical studies of ischemic and nonischemic cardiomyopathy employing MSC-based therapy have demonstrated that the properties of reducing fibrosis, stimulating angiogenesis, and cardiomyogenesis have led to improvements in the structure and function of remodeled ventricles. Further attempts have been made to augment MSCs' effects through genetic modification and cell preconditioning. Progression of MSC therapy to early clinical trials has supported their role in improving cardiac structure and function, functional capacity, and patient quality of life. Emerging data have supported larger clinical trials that have been either completed or are currently underway. Mechanistically, MSC therapy is thought to benefit the heart by stimulating innate anti-fibrotic and regenerative responses. The mechanisms of action involve paracrine signaling, cell-cell interactions, and fusion with resident cells. Trans-differentiation of MSCs to bona fide cardiomyocytes and coronary vessels is also thought to occur, although at a nonphysiological level. Recently, MSC-based tissue engineering for cardiovascular disease has been examined with quite encouraging results. This review discusses MSCs from their basic biological characteristics to their role as a promising therapeutic strategy for clinical cardiovascular disease. Copyright © 2016 the American Physiological Society.

Tissue engineering.

PubMed

Katari, Ravi S; Peloso, Andrea; Orlando, Giuseppe

2014-01-01

Ultimately much work remains to be done in the companion fields of biomaterials and stem cells. Nonetheless, the monumental progress in TE that has been reported in the studies summarized here demonstrates that regenerative approaches to problems in general surgery need to be explored in more depth. Furthermore, the surgical disciplines of reconstruction and transplantation need to recognize their research counterparts in TE, given its potential to actualize freedom from immunosuppression, one of the most elusive goals in modern surgery. The engineering and proliferation of autologous cells, tissues, and organs ex vivo before surgical operation can significantly reduce the obstacles current practitioners are intimately familiar with: donor site morbidity and immunologic rejection. Therefore, in addition to the truly exciting research and development prospects and implications for the commercial sector, patients with end-stage diseases and debilitating injury stand to gain the most from clinically adapted TE therapies.

From Microscale Devices to 3D Printing: Advances in Fabrication of 3D Cardiovascular Tissues

PubMed Central

Borovjagin, Anton V.; Ogle, Brenda; Berry, Joel; Zhang, Jianyi

2016-01-01

Current strategies for engineering cardiovascular cells and tissues have yielded a variety of sophisticated tools for studying disease mechanisms, for development of drug therapies, and for fabrication of tissue equivalents that may have application in future clinical use. These efforts are motivated by the need to extend traditional two-dimensional (2D) cell culture systems into 3D to more accurately replicate in vivo cell and tissue function of cardiovascular structures. Developments in microscale devices and bioprinted 3D tissues are beginning to supplant traditional 2D cell cultures and pre-clinical animal studies that have historically been the standard for drug and tissue development. These new approaches lend themselves to patient-specific diagnostics, therapeutics, and tissue regeneration. The emergence of these technologies also carries technical challenges to be met before traditional cell culture and animal testing become obsolete. Successful development and validation of 3D human tissue constructs will provide powerful new paradigms for more cost effective and timely translation of cardiovascular tissue equivalents. PMID:28057791

Tissue-engineered composite scaffold of poly(lactide-co-glycolide) and hydroxyapatite nanoparticles seeded with autologous mesenchymal stem cells for bone regeneration*

PubMed Central

Zhang, Bing; Zhang, Pei-biao; Wang, Zong-liang; Lyu, Zhong-wen; Wu, Han

2017-01-01

Objective: A new therapeutic strategy using nanocomposite scaffolds of grafted hydroxyapatite (g-HA)/poly(lactide-co-glycolide) (PLGA) carried with autologous mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) was assessed for the therapy of critical bone defects. At the same time, tissue response and in vivo mineralization of tissue-engineered implants were investigated. Methods: A composite scaffold of PLGA and g-HA was fabricated by the solvent casting and particulate-leaching method. The tissue-engineered implants were prepared by seeding the scaffolds with autologous bone marrow MSCs in vitro. Then, mineralization and osteogenesis were observed by intramuscular implantation, as well as the repair of the critical radius defects in rabbits. Results: After eight weeks post-surgery, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that g-HA/PLGA had a better interface of tissue response and higher mineralization than PLGA. Apatite particles were formed and varied both in macropores and micropores of g-HA/PLGA. Computer radiographs and histological analysis revealed that there were more and more quickly formed new bone formations and better fusion in the bone defect areas of g-HA/PLGA at 2–8 weeks post-surgery. Typical bone synostosis between the implant and bone tissue was found in g-HA/PLGA, while only fibrous tissues formed in PLGA. Conclusions: The incorporation of g-HA mainly improved mineralization and bone formation compared with PLGA. The application of MSCs can enhance bone formation and mineralization in PLGA scaffolds compared with cell-free scaffolds. Furthermore, it can accelerate the absorption of scaffolds compared with composite scaffolds. PMID:29119734

Tissue-engineered composite scaffold of poly(lactide-co-glycolide) and hydroxyapatite nanoparticles seeded with autologous mesenchymal stem cells for bone regeneration.

PubMed

Zhang, Bing; Zhang, Pei-Biao; Wang, Zong-Liang; Lyu, Zhong-Wen; Wu, Han

A new therapeutic strategy using nanocomposite scaffolds of grafted hydroxyapatite (g-HA)/ poly(lactide-co-glycolide) (PLGA) carried with autologous mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) was assessed for the therapy of critical bone defects. At the same time, tissue response and in vivo mineralization of tissue-engineered implants were investigated. A composite scaffold of PLGA and g-HA was fabricated by the solvent casting and particulate-leaching method. The tissue-engineered implants were prepared by seeding the scaffolds with autologous bone marrow MSCs in vitro. Then, mineralization and osteogenesis were observed by intramuscular implantation, as well as the repair of the critical radius defects in rabbits. After eight weeks post-surgery, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that g-HA/PLGA had a better interface of tissue response and higher mineralization than PLGA. Apatite particles were formed and varied both in macropores and micropores of g-HA/PLGA. Computer radiographs and histological analysis revealed that there were more and more quickly formed new bone formations and better fusion in the bone defect areas of g-HA/PLGA at 2-8 weeks post-surgery. Typical bone synostosis between the implant and bone tissue was found in g-HA/PLGA, while only fibrous tissues formed in PLGA. The incorporation of g-HA mainly improved mineralization and bone formation compared with PLGA. The application of MSCs can enhance bone formation and mineralization in PLGA scaffolds compared with cell-free scaffolds. Furthermore, it can accelerate the absorption of scaffolds compared with composite scaffolds.

Fabrication of myogenic engineered tissue constructs.

PubMed

Pacak, Christina A; Cowan, Douglas B

2009-05-01

Despite the fact that electronic pacemakers are life-saving medical devices, their long-term performance in pediatric patients can be problematic owing to the restrictions imposed by a child's small size and their inevitable growth. Consequently, there is a genuine need for innovative therapies designed specifically for pediatric patients with cardiac rhythm disorders. We propose that a conductive biological alternative consisting of a collagen-based matrix containing autologously-derived cells could better adapt to growth, reduce the need for recurrent surgeries, and greatly improve the quality of life for these patients. In the present study, we describe a procedure for incorporating primary skeletal myoblast cell cultures within a hydrogel matrix to fashion a surgically-implantable tissue construct that will serve as an electrical conduit between the upper and lower chambers of the heart. Ultimately, we anticipate using this type of engineered tissue to restore atrioventricular electrical conduction in children with complete heart block. In view of that, we isolate myoblasts from the skeletal muscles of neonatal Lewis rats and plate them onto laminin-coated tissue culture dishes using a modified version of established protocols. After one to two days, cultured cells are collected and mixed with antibiotics, type 1 collagen, Matrigel, and NaHCO(3). The result is a viscous, uniform solution that can be cast into a mold of nearly any shape and size. For our tissue constructs, we employ type 1 collagen isolated from fetal lamb skin using standard procedures. Once the tissue has solidified at 37 degrees C, culture media is carefully added to the plate until the construct is submerged. The engineered tissue is then allowed to further condense through dehydration for 2 more days, at which point it is ready for in vitro assessment or surgical-implantation.

Nasal chondrocyte-based engineered autologous cartilage tissue for repair of articular cartilage defects: an observational first-in-human trial.

PubMed

Mumme, Marcus; Barbero, Andrea; Miot, Sylvie; Wixmerten, Anke; Feliciano, Sandra; Wolf, Francine; Asnaghi, Adelaide M; Baumhoer, Daniel; Bieri, Oliver; Kretzschmar, Martin; Pagenstert, Geert; Haug, Martin; Schaefer, Dirk J; Martin, Ivan; Jakob, Marcel

2016-10-22

Articular cartilage injuries have poor repair capacity, leading to progressive joint damage, and cannot be restored predictably by either conventional treatments or advanced therapies based on implantation of articular chondrocytes. Compared with articular chondrocytes, chondrocytes derived from the nasal septum have superior and more reproducible capacity to generate hyaline-like cartilage tissues, with the plasticity to adapt to a joint environment. We aimed to assess whether engineered autologous nasal chondrocyte-based cartilage grafts allow safe and functional restoration of knee cartilage defects. In a first-in-human trial, ten patients with symptomatic, post-traumatic, full-thickness cartilage lesions (2-6 cm 2 ) on the femoral condyle or trochlea were treated at University Hospital Basel in Switzerland. Chondrocytes isolated from a 6 mm nasal septum biopsy specimen were expanded and cultured onto collagen membranes to engineer cartilage grafts (30 × 40 × 2 mm). The engineered tissues were implanted into the femoral defects via mini-arthrotomy and assessed up to 24 months after surgery. Primary outcomes were feasibility and safety of the procedure. Secondary outcomes included self-assessed clinical scores and MRI-based estimation of morphological and compositional quality of the repair tissue. This study is registered with ClinicalTrials.gov, number NCT01605201. The study is ongoing, with an approved extension to 25 patients. For every patient, it was feasible to manufacture cartilaginous grafts with nasal chondrocytes embedded in an extracellular matrix rich in glycosaminoglycan and type II collagen. Engineered tissues were stable through handling with forceps and could be secured in the injured joints. No adverse reactions were recorded and self-assessed clinical scores for pain, knee function, and quality of life were improved significantly from before surgery to 24 months after surgery. Radiological assessments indicated variable degrees of defect filling and development of repair tissue approaching the composition of native cartilage. Hyaline-like cartilage tissues, engineered from autologous nasal chondrocytes, can be used clinically for repair of articular cartilage defects in the knee. Future studies are warranted to assess efficacy in large controlled trials and to investigate an extension of indications to early degenerative states or to other joints. Deutsche Arthrose-Hilfe. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gene therapy approaches for spinal cord injury

NASA Astrophysics Data System (ADS)

Bright, Corinne

As the biomedical engineering field expands, combination technologies are demonstrating enormous potential for treating human disease. In particular, intersections between the rapidly developing fields of gene therapy and tissue engineering hold promise to achieve tissue regeneration. Nonviral gene therapy uses plasmid DNA to deliver therapeutic proteins in vivo for extended periods of time. Tissue engineering employs biomedical materials, such as polymers, to support the regrowth of injured tissue. In this thesis, a combination strategy to deliver genes and drugs in a polymeric scaffold was applied to a spinal cord injury model. In order to develop a platform technology to treat spinal cord injury, several nonviral gene delivery systems and polymeric scaffolds were evaluated in vitro and in vivo. Nonviral vector trafficking was evaluated in primary neuronal culture to develop an understanding of the barriers to gene transfer in neurons and their supporting glia. Although the most efficient gene carrier in vitro differed from the optimal gene carrier in vivo, confocal and electron microscopy of these nonviral vectors provided insights into the interaction of these vectors with the nucleus. A novel pathway for delivering nanoparticles into the nuclei of neurons and Schwann cells via vesicle trafficking was observed in this study. Reporter gene expression levels were evaluated after direct and remote delivery to the spinal cord, and the optimal nonviral vector, dose, and delivery strategy were applied to deliver the gene encoding the basic fibroblast growth factor (bFGF) to the spinal cord. An injectable and biocompatible gel, composed of the amphiphillic polymer poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG) was evaluated as a drug and gene delivery system in vitro, and combined with the optimized nonviral gene delivery system to treat spinal cord injury. Plasmid DNA encoding the bFGF gene and the therapeutic NEP1--40 peptide were incorporated in the PEG-PCL-PEG gel and injected into a lesion transecting the main dorsomedial and minor ventral medial corticospinal tract (CST). The degree of collateralization of the transected CST was quantified as an indicator of the regenerative potential of these treatments. At one month post-injury, we observed the robust rostral collateralization of the CST tract in response to the bFGF plasmid-loaded gel. In conclusion, we hope that this platform technology can be applied to the sustained local delivery of other proteins for the treatment of spinal cord injury.

Engineering brown fat into skeletal muscle using ultrasound-targeted microbubble destruction gene delivery in obese Zucker rats: Proof of concept design.

PubMed

Bastarrachea, Raul A; Chen, Jiaxi; Kent, Jack W; Nava-Gonzalez, Edna J; Rodriguez-Ayala, Ernesto; Daadi, Marcel M; Jorge, Barbara; Laviada-Molina, Hugo; Comuzzie, Anthony G; Chen, Shuyuan; Grayburn, Paul A

2017-09-01

Ultrasound-targeted microbubble destruction (UTMD) is a novel means of tissue-specific gene delivery. This approach systemically infuses transgenes precoupled to gas-filled lipid microbubbles that are burst within the microvasculature of target tissues via an ultrasound signal resulting in release of DNA and transfection of neighboring cells within the tissue. Previous work has shown that adenovirus containing cDNA of UCP-1, injected into the epididymal fat pads in mice, induced localized fat depletion, improving glucose tolerance, and decreasing food intake in obese diabetic mice. Our group recently demonstrated that gene therapy by UTMD achieved beta cell regeneration in streptozotocin (STZ)-treated mice and baboons. We hypothesized that gene therapy with BMP7/PRDM16/PPARGC1A in skeletal muscle (SKM) of obese Zucker diabetic fatty (fa/fa) rats using UTMD technology would produce a brown adipose tissue (BAT) phenotype with UCP-1 overexpression. This study was designed as a proof of concept (POC) project. Obese Zucker rats were administered plasmid cDNA contructs encoding a gene cocktail with BMP7/PRDM16/PPARGC1A incorporated within microbubbles and intravenously delivered into their left thigh. Controls received UTMD with plasmids driving a DsRed reporter gene. An ultrasound transducer was directed to the thigh to disrupt the microbubbles within the microcirculation. Blood samples were drawn at baseline, and after treatment to measure glucose, insulin, and free fatty acids levels. SKM was harvested for immunohistochemistry (IHC). Our IHC results showed a reliable pattern of effective UTMD-based gene delivery in enhancing SKM overexpression of the UCP-1 gene. This clearly indicates that our plasmid DNA construct encoding the gene combination of PRDM16, PPARGC1A, and BMP7 reprogrammed adult SKM tissue into brown adipose cells in vivo. Our pilot established POC showing that the administration of the gene cocktail to SKM in this rat model of genetic obesity using UTMD gene therapy, engineered a BAT phenotype with UCP-1 over-expression. © 2017 IUBMB Life, 69(9):745-755, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

A comparison of the functionality and in vivo phenotypic stability of cartilaginous tissues engineered from different stem cell sources.

PubMed

Vinardell, Tatiana; Sheehy, Eamon J; Buckley, Conor T; Kelly, Daniel J

2012-06-01

Joint-derived stem cells are a promising alternative cell source for cartilage repair therapies that may overcome many of the problems associated with the use of primary chondrocytes (CCs). The objective of this study was to compare the in vitro functionality and in vivo phenotypic stability of cartilaginous tissues engineered using bone marrow-derived stem cells (BMSCs) and joint tissue-derived stem cells following encapsulation in agarose hydrogels. Culture-expanded BMSCs, fat pad-derived stem cells (FPSCs), and synovial membrane-derived stem cells (SDSCs) were encapsulated in agarose and maintained in a chondrogenic medium supplemented with transforming growth factor-β3. After 21 days of culture, constructs were either implanted subcutaneously into the back of nude mice for an additional 28 days or maintained for a similar period in vitro in either chondrogenic or hypertrophic media formulations. After 49 days of in vitro culture in chondrogenic media, SDSC constructs accumulated the highest levels of sulfated glycosaminoglycan (sGAG) (∼2.8% w/w) and collagen (∼1.8% w/w) and were mechanically stiffer than constructs engineered using other cell types. After subcutaneous implantation in nude mice, sGAG content significantly decreased for all stem cell-seeded constructs, while no significant change was observed in the control constructs engineered using primary CCs, indicating that the in vitro chondrocyte-like phenotype generated in all stem cell-seeded agarose constructs was transient. FPSCs and SDSCs appeared to undergo fibrous dedifferentiation or resorption, as evident from increased collagen type I staining and a dramatic loss in sGAG content. BMSCs followed a more endochondral pathway with increased type X collagen expression and mineralization of the engineered tissue. In conclusion, while joint tissue-derived stem cells possess a strong intrinsic chondrogenic capacity, further studies are needed to identify the factors that will lead to the generation of a more stable chondrogenic phenotype.

Ultrasound-assisted liposuction provides a source for functional adipose-derived stromal cells.

PubMed

Duscher, Dominik; Maan, Zeshaan N; Luan, Anna; Aitzetmüller, Matthias M; Brett, Elizabeth A; Atashroo, David; Whittam, Alexander J; Hu, Michael S; Walmsley, Graham G; Houschyar, Khosrow S; Schilling, Arndt F; Machens, Hans-Guenther; Gurtner, Geoffrey C; Longaker, Michael T; Wan, Derrick C

2017-12-01

Regenerative medicine employs human mesenchymal stromal cells (MSCs) for their multi-lineage plasticity and their pro-regenerative cytokine secretome. Adipose-derived mesenchymal stromal cells (ASCs) are concentrated in fat tissue, and the ease of harvest via liposuction makes them a particularly interesting cell source. However, there are various liposuction methods, and few have been assessed regarding their impact on ASC functionality. Here we study the impact of the two most popular ultrasound-assisted liposuction (UAL) devices currently in clinical use, VASER (Solta Medical) and Lysonix 3000 (Mentor) on ASCs. After lipoaspirate harvest and processing, we sorted for ASCs using fluorescent-assisted cell sorting based on an established surface marker profile (CD34 + CD31 - CD45 - ). ASC yield, viability, osteogenic and adipogenic differentiation capacity and in vivo regenerative performance were assessed. Both UAL samples demonstrated equivalent ASC yield and viability. VASER UAL ASCs showed higher osteogenic and adipogenic marker expression, but a comparable differentiation capacity was observed. Soft tissue healing and neovascularization were significantly enhanced via both UAL-derived ASCs in vivo, and there was no significant difference between the cell therapy groups. Taken together, our data suggest that UAL allows safe and efficient harvesting of the mesenchymal stromal cellular fraction of adipose tissue and that cells harvested via this approach are suitable for cell therapy and tissue engineering applications. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Bone Tissue Engineering Under Xenogeneic-Free Conditions in a Large Animal Model as a Basis for Early Clinical Applicability.

PubMed

Weigand, Annika; Beier, Justus P; Schmid, Rafael; Knorr, Tobias; Kilian, David; Götzl, Rebekka; Gerber, Thomas; Horch, Raymund E; Boos, Anja M

2017-03-01

For decades, researchers have been developing a range of promising strategies in bone tissue engineering with the aim of producing a significant clinical benefit over existing therapies. However, a major problem concerns the traditional use of xenogeneic substances for the expansion of cells, which complicates direct clinical transfer. The study's aim was to establish a totally autologous sheep model as a basis for further preclinical studies and future clinical application. Ovine mesenchymal stromal cells (MSC) were cultivated in different concentrations (0%, 2%, 5%, 10%, and 25%) of either autologous serum (AS) or fetal calf serum (FCS). With an increase of serum concentration, enhanced metabolic activity and proliferation could be observed. There were minor differences between MSC cultivated in AS or FCS, comparing gene and protein expression of osteogenic and stem cell markers, morphology, and osteogenic differentiation. MSC implanted subcutaneously in the sheep model, together with a nanostructured bone substitute, either in stable block or moldable putty form, induced similar vascularization and remodeling of the bone substitute irrespective of cultivation of MSC in AS or FCS and osteogenic differentiation. The bone substitute in block form together with MSC proved particularly advantageous in the induction of ectopic bone formation compared to the cell-free control and putty form. It could be demonstrated that AS is suitable for replacement of FCS for cultivation of ovine MSC for bone tissue engineering purposes. Substantial progress has been made in the development of a strictly xenogeneic-free preclinical animal model to bring future clinical application of bone tissue engineering strategies within reach.

Gene therapy in dentistry: tool of genetic engineering. Revisited.

PubMed

Gupta, Khushboo; Singh, Saurabh; Garg, Kavita Nitish

2015-03-01

Advances in biotechnology have brought gene therapy to the forefront of medical research. The concept of transferring genes to tissues for clinical applications has been discussed nearly half a century, but the ability to manipulate genetic material via recombinant DNA technology has brought this goal to reality. The feasibility of gene transfer was first demonstrated using tumour viruses. This led to development of viral and nonviral methods for the genetic modification of somatic cells. Applications of gene therapy to dental and oral problems illustrate the potential impact of this technology on dentistry. Preclinical trial results regarding the same have been very promising. In this review we will discuss methods, vectors involved, clinical implication in dentistry and scientific issues associated with gene therapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of Tamoxifen and oestrogen on histology and radiographic density in high and low mammographic density human breast tissues maintained in murine tissue engineering chambers.

PubMed

Chew, G L; Huo, C W; Huang, D; Blick, T; Hill, P; Cawson, J; Frazer, H; Southey, M C; Hopper, J L; Britt, K; Henderson, M A; Haviv, I; Thompson, E W

2014-11-01

Mammographic density (MD) is a strong risk factor for breast cancer. It is altered by exogenous endocrine treatments, including hormone replacement therapy and Tamoxifen. Such agents also modify breast cancer (BC) risk. However, the biomolecular basis of how systemic endocrine therapy modifies MD and MD-associated BC risk is poorly understood. This study aims to determine whether our xenograft biochamber model can be used to study the effectiveness of therapies aimed at modulating MD, by examine the effects of Tamoxifen and oestrogen on histologic and radiographic changes in high and low MD tissues maintained within the biochamber model. High and low MD human tissues were precisely sampled under radiographic guidance from prophylactic mastectomy fresh specimens of high-risk women, then inserted into separate vascularized murine biochambers. The murine hosts were concurrently implanted with Tamoxifen, oestrogen or placebo pellets, and the high and low MD biochamber tissues maintained in the murine host environment for 3 months, before the high and low MD biochamber tissues were harvested for histologic and radiographic analyses. The radiographic density of high MD tissue maintained in murine biochambers was decreased in Tamoxifen-treated mice compared to oestrogen-treated mice (p = 0.02). Tamoxifen treatment of high MD tissue in SCID mice led to a decrease in stromal (p = 0.009), and an increase in adipose (p = 0.023) percent areas, compared to placebo-treated mice. No histologic or radiographic differences were observed in low MD biochamber tissue with any treatment. High MD biochamber tissues maintained in mice implanted with Tamoxifen, oestrogen or placebo pellets had dynamic and measurable histologic compositional and radiographic changes. This further validates the dynamic nature of the MD xenograft model, and suggests the biochamber model may be useful for assessing the underlying molecular pathways of Tamoxifen-reduced MD, and in testing of other pharmacologic interventions in a preclinical model of high MD.

Testing Current and Developing Novel Therapies for NF1-Mutant Sarcomas in a Genetically Engineered Mouse Model

DTIC Science & Technology

2015-04-01

Patients with Neurofibromatosis type 1 (NF1) are at increased risk for developing malignant tumors of the connective tissue called soft-tissue sarcomas...mouse model, MPNST, Neurofibromatosis , NF1 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE...9 9. Appendices……………………………………………………………9 4   1. INTRODUCTION: Patients with Neurofibromatosis type 1 (NF1) are at increased risk for

Functionalized Nanostructures with Application in Regenerative Medicine

PubMed Central

Perán, Macarena; García, María A.; López-Ruiz, Elena; Bustamante, Milán; Jiménez, Gema; Madeddu, Roberto; Marchal, Juan A.

2012-01-01

In the last decade, both regenerative medicine and nanotechnology have been broadly developed leading important advances in biomedical research as well as in clinical practice. The manipulation on the molecular level and the use of several functionalized nanoscaled materials has application in various fields of regenerative medicine including tissue engineering, cell therapy, diagnosis and drug and gene delivery. The themes covered in this review include nanoparticle systems for tracking transplanted stem cells, self-assembling peptides, nanoparticles for gene delivery into stem cells and biomimetic scaffolds useful for 2D and 3D tissue cell cultures, transplantation and clinical application. PMID:22489186

Future and Advances in Endoscopy

PubMed Central

Elahi, Sakib F.; Wang, Thomas D.

2012-01-01

The future of endoscopy will be dictated by rapid technological advances in the development of light sources, optical fibers, and miniature scanners that will allow for images to be collected in multiple spectral regimes, with greater tissue penetration, and in three dimensions. These engineering breakthroughs will be integrated with novel molecular probes that are highly specific for unique proteins to target diseased tissues. Applications include early cancer detection by imaging molecular changes that occur before gross morphological abnormalities, personalized medicine by visualizing molecular targets specific to individual patients, and image guided therapy by localizing tumor margins and monitoring for recurrence. PMID:21751414

Magnetic nanoparticle-based approaches to locally target therapy and enhance tissue regeneration in vivo.

PubMed

Sensenig, Richard; Sapir, Yulia; MacDonald, Cristin; Cohen, Smadar; Polyak, Boris

2012-09-01

Magnetic-based systems utilizing superparamagnetic nanoparticles and a magnetic field gradient to exert a force on these particles have been used in a wide range of biomedical applications. This review is focused on drug targeting applications that require penetration of a cellular barrier as well as strategies to improve the efficacy of targeting in these biomedical applications. Another focus of this review is regenerative applications utilizing tissue engineered scaffolds prepared with the aid of magnetic particles, the use of remote actuation for release of bioactive molecules and magneto-mechanical cell stimulation, cell seeding and cell patterning.

Comparative study of the chondrogenic potential of human bone marrow stromal cells, neonatal chondrocytes and adult chondrocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saha, Sushmita; Kirkham, Jennifer; NIHR Leeds Musculoskeletal Biomedical Research Unit, University of Leeds, Chapel Allerton Hospital, Leeds LS74SA

2010-10-22

Research highlights: {yields} This study has characterised three different cell types under conditions similar to those used for autologous chondrocyte implantation (ACI) for applications in cartilage repair/regeneration. {yields} Compared for the first time the chondrogenic potential of neonatal chondrocytes with human bone marrow stromal cells (HBMSCs) and adult chondrocytes. {yields} Demonstrated that adult chondrocytes hold greatest potential for use in ACI based on their higher proliferation rates, lower alkaline phosphatise activity and enhanced expression of chondrogenic genes. {yields} Demonstrated the need for chondroinduction as a necessary pre-requisite to efficient chondrogenesis in vitro and, by extrapolation, for cell based therapy (e.g.more » ACI or cartilage tissue engineering). -- Abstract: Cartilage tissue engineering is still a major clinical challenge with optimisation of a suitable source of cells for cartilage repair/regeneration not yet fully addressed. The aims of this study were to compare and contrast the differences in chondrogenic behaviour between human bone marrow stromal cells (HBMSCs), human neonatal and adult chondrocytes to further our understanding of chondroinduction relative to cell maturity and to identify factors that promote chondrogenesis and maintain functional homoeostasis. Cells were cultured in monolayer in either chondrogenic or basal medium, recapitulating procedures used in existing clinical procedures for cell-based therapies. Cell doubling time, morphology and alkaline phosphatase specific activity (ALPSA) were determined at different time points. Expression of chondrogenic markers (SOX9, ACAN and COL2A1) was compared via real time polymerase chain reaction. Amongst the three cell types studied, HBMSCs had the highest ALPSA in basal culture and lowest ALPSA in chondrogenic media. Neonatal chondrocytes were the most proliferative and adult chondrocytes had the lowest ALPSA in basal media. Gene expression analysis revealed a difference in the temporal expression of chondrogenic markers which were up regulated in chondrogenic medium compared to levels in basal medium. Of the three cell types studied, adult chondrocytes offer a more promising cell source for cartilage tissue engineering. This comparative study revealed differences between the microenvironment of all three cell types and provides useful information to inform cell-based therapies for cartilage regeneration.« less

Engineered in vitro disease models.

PubMed

Benam, Kambez H; Dauth, Stephanie; Hassell, Bryan; Herland, Anna; Jain, Abhishek; Jang, Kyung-Jin; Karalis, Katia; Kim, Hyun Jung; MacQueen, Luke; Mahmoodian, Roza; Musah, Samira; Torisawa, Yu-suke; van der Meer, Andries D; Villenave, Remi; Yadid, Moran; Parker, Kevin K; Ingber, Donald E

2015-01-01

The ultimate goal of most biomedical research is to gain greater insight into mechanisms of human disease or to develop new and improved therapies or diagnostics. Although great advances have been made in terms of developing disease models in animals, such as transgenic mice, many of these models fail to faithfully recapitulate the human condition. In addition, it is difficult to identify critical cellular and molecular contributors to disease or to vary them independently in whole-animal models. This challenge has attracted the interest of engineers, who have begun to collaborate with biologists to leverage recent advances in tissue engineering and microfabrication to develop novel in vitro models of disease. As these models are synthetic systems, specific molecular factors and individual cell types, including parenchymal cells, vascular cells, and immune cells, can be varied independently while simultaneously measuring system-level responses in real time. In this article, we provide some examples of these efforts, including engineered models of diseases of the heart, lung, intestine, liver, kidney, cartilage, skin and vascular, endocrine, musculoskeletal, and nervous systems, as well as models of infectious diseases and cancer. We also describe how engineered in vitro models can be combined with human inducible pluripotent stem cells to enable new insights into a broad variety of disease mechanisms, as well as provide a test bed for screening new therapies.

Tissue Engineering Stem Cells – An e-Governance Strategy

PubMed Central

Grange, Simon

2011-01-01

The rules of governance are changing. They are necessarily becoming more stringent as interventions offered to treat conditions carry unpredictable side effects, often associated with novel therapeutic vectors. The clinical relevance of this relates to the obligations of those involved in research, to ensure the best protection for subjects whilst encouraging the development of the field. Existing evidence supports the concept of e-Governance both in operational health research and more broadly in the strategic domain of policy formation. Building on the impact of the UK Comprehensive Research Network and recent EU Directives, it is now possible to focus on the issues of regulation for cell therapies in musculoskeletal science through the development of the Advanced Therapeutic Medicinal Products (ATMP) category of research products. This article reviews the framework that has borne this and the need for more detailed Virtual Research Integration and Collaboration (VRIC) systems to ensure regulatory compliance. Technology research and development plans must develop in close association between tissue engineering and treating clinicians. The scope of this strategy relates to the handling of human tissues the transport and storage of specimens in accordance with current EU directives and the Human Tissue Authority (HTA) regulations. PMID:21886693

Size-engineered biocompatible polymeric nanophotosensitizer for locoregional photodynamic therapy of cancer.

PubMed

Jeong, Keunsoo; Park, Solji; Lee, Yong-Deok; Kang, Chi Soo; Kim, Hyun Jun; Park, Hyeonjong; Kwon, Ick Chan; Kim, Jungahn; Park, Chong Rae; Kim, Sehoon

2016-08-01

Current approaches in use of water-insoluble photosensitizers for photodynamic therapy (PDT) of cancer often demand a nano-delivery system. Here, we report a photosensitizer-loaded biocompatible nano-delivery formulation (PPaN-20) whose size was engineered to ca. 20nm to offer improved cell/tissue penetration and efficient generation of cytotoxic singlet oxygen. PPaN-20 was fabricated through the physical assembly of all biocompatible constituents: pyropheophorbide-a (PPa, water-insoluble photosensitizer), polycaprolactone (PCL, hydrophobic/biodegradable polymer), and Pluronic F-68 (clinically approved polymeric surfactant). Repeated microemulsification/evaporation method resulted in a fine colloidal dispersion of PPaN-20 in water, where the particulate PCL matrix containing well-dispersed PPa molecules inside was stabilized by the Pluronic corona. Compared to a control sample of large-sized nanoparticles (PPaN-200) prepared by a conventional solvent displacement method, PPaN-20 revealed optimal singlet oxygen generation and efficient cellular uptake by virtue of the suitably engineered size and constitution, leading to high in vitro phototoxicity against cancer cells. Upon administration to tumor-bearing mice by peritumoral route, PPaN-20 showed efficient tumor accumulation by the enhanced cell/tissue penetration evidenced by in vivo near-infrared fluorescence imaging. The in vivo PDT treatment with peritumorally administrated PPaN-20 showed significantly enhanced suppression of tumor growth compared to the control group, demonstrating great potential as a biocompatible photosensitizing agent for locoregional PDT treatment of cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

Scaffold translation: barriers between concept and clinic.

PubMed

Hollister, Scott J; Murphy, William L

2011-12-01

Translation of scaffold-based bone tissue engineering (BTE) therapies to clinical use remains, bluntly, a failure. This dearth of translated tissue engineering therapies (including scaffolds) remains despite 25 years of research, research funding totaling hundreds of millions of dollars, over 12,000 papers on BTE and over 2000 papers on BTE scaffolds alone in the past 10 years (PubMed search). Enabling scaffold translation requires first an understanding of the challenges, and second, addressing the complete range of these challenges. There are the obvious technical challenges of designing, manufacturing, and functionalizing scaffolds to fill the Form, Fixation, Function, and Formation needs of bone defect repair. However, these technical solutions should be targeted to specific clinical indications (e.g., mandibular defects, spine fusion, long bone defects, etc.). Further, technical solutions should also address business challenges, including the need to obtain regulatory approval, meet specific market needs, and obtain private investment to develop products, again for specific clinical indications. Finally, these business and technical challenges present a much different model than the typical research paradigm, presenting the field with philosophical challenges in terms of publishing and funding priorities that should be addressed as well. In this article, we review in detail the technical, business, and philosophical barriers of translating scaffolds from Concept to Clinic. We argue that envisioning and engineering scaffolds as modular systems with a sliding scale of complexity offers the best path to addressing these translational challenges. © Mary Ann Liebert, Inc.

Novel immunotherapies for hematological malignancies

PubMed Central

Nelson, Michelle H.; Paulos, Chrystal M.

2014-01-01

Summary The immune system is designed to discriminate between self and tumor tissue. Through genetic recombination, there is fundamentally no limit to the number of tumor antigens that immune cells can recognize. Yet, tumors use a variety of immunosuppressive mechanisms to evade immunity. Insight into how the immune system interacts with tumors is expanding rapidly and has accelerated the translation of immunotherapies into medical breakthroughs. Herein, we appraise the state of the art in immunotherapy with a focus on strategies that exploit the patient’s immune system to kill cancer. We review various forms of immune-based therapies, which have shown significant promise in patients with hematological malignancies, including (i) conventional monoclonal therapies like rituximab, (ii) engineered monoclonal antibodies called bispecific T cell engagers (BiTEs), (iii) monoclonal antibodies and pharmaceutical drugs that block inhibitory T-cell pathways (i.e. PD-1, CTLA-4 and IDO), and (iv) adoptive cell transfer (ACT) therapy with T cells engineered to express chimeric antigen receptors (CARs) or T-cell receptors (TCRs). We also assess the idea of using these therapies in combination and conclude by suggesting multi-prong approaches to improve treatment outcomes and curative responses in patients. PMID:25510273

Long-term culture of human liver tissue with advanced hepatic functions.

PubMed

Ng, Soon Seng; Xiong, Anming; Nguyen, Khanh; Masek, Marilyn; No, Da Yoon; Elazar, Menashe; Shteyer, Eyal; Winters, Mark A; Voedisch, Amy; Shaw, Kate; Rashid, Sheikh Tamir; Frank, Curtis W; Cho, Nam Joon; Glenn, Jeffrey S

2017-06-02

A major challenge for studying authentic liver cell function and cell replacement therapies is that primary human hepatocytes rapidly lose their advanced function in conventional, 2-dimensional culture platforms. Here, we describe the fabrication of 3-dimensional hexagonally arrayed lobular human liver tissues inspired by the liver's natural architecture. The engineered liver tissues exhibit key features of advanced differentiation, such as human-specific cytochrome P450-mediated drug metabolism and the ability to support efficient infection with patient-derived inoculums of hepatitis C virus. The tissues permit the assessment of antiviral agents and maintain their advanced functions for over 5 months in culture. This extended functionality enabled the prediction of a fatal human-specific hepatotoxicity caused by fialuridine (FIAU), which had escaped detection by preclinical models and short-term clinical studies. The results obtained with the engineered human liver tissue in this study provide proof-of-concept determination of human-specific drug metabolism, demonstrate the ability to support infection with human hepatitis virus derived from an infected patient and subsequent antiviral drug testing against said infection, and facilitate detection of human-specific drug hepatotoxicity associated with late-onset liver failure. Looking forward, the scalability and biocompatibility of the scaffold are also ideal for future cell replacement therapeutic strategies.

[Academic cell therapy facilities are challenged by European regulation on advanced therapy medicinal products].

PubMed

Chabannon, Christian; Sabatier, Florence; Rial-Sebbag, Emmanuelle; Calmels, Boris; Veran, Julie; Magalon, Guy; Lemarie, Claude; Mahalatchimy, Aurélie

2014-05-01

Regulation (EC) n° 1394/2007 from the European Parliament and the Council describes a new category of health products termed « Advanced Therapy Medicinal Products » (ATMPs). ATMPs derive from cell engineering, tissue engineering or genetic manipulations, and can in some instances be combined with medical devices. ATMPs are distributed and administered to patients, after biotechnology or pharmaceutical companies have obtained a marketing authorization that is granted by the European Commission on the basis of the European Medicines Agency (EMA) assessment. Seven years after the publication of the regulation, few of these therapies have received a marketing authorization, and even fewer have met commercial success, suggesting that a number of medical and economic issues still need to be sorted out in order to achieve sustainability in this field. The coexistence of three sets of rules for three categories of health products that are biologically and medically related - ATMPs, ATMPs produced under the hospital exemption rule, and cell therapy products (CTPs) (a specific legal category in France) that have long been used in hematopoietic cell transplantation - constitutes a complex regulatory framework. This situation raises significant issues for historical as well as emerging operators in this moving field that are discussed thereafter. © 2014 médecine/sciences – Inserm.

Redefining the potential applications of dental stem cells: An asset for future

PubMed Central

Rai, Shalu; Kaur, Mandeep; Kaur, Sandeep; Arora, Sapna Panjwani

2012-01-01

Recent exciting discoveries isolated dental stem cells from the pulp of the primary and permanent teeth, from the periodontal ligament, and from associated healthy tissues. Dental pulp stem cells (DPSCs) represent a kind of adult cell colony which has the potent capacity of self-renewing and multilineage differentiation. Stem cell-based tooth engineering is deemed as a promising approach to the making of a biological tooth (bio-tooth) or engineering of functional tooth structures. Dental professionals have the opportunity to make their patients aware of these new sources of stem cells that can be stored for future use as new therapies are developed for a range of diseases and injuries. The aim of this article is to review and understand how dental stem cells are being used for regeneration of oral and conversely nonoral tissues. A brief review on banking is also done for storing of these valuable stem cells for future use. PMID:23716933

Regulation of mesenchymal stem cell 3D microenvironment: From macro to microfluidic bioreactors.

PubMed

Sart, Sébastien; Agathos, Spiros N; Li, Yan; Ma, Teng

2016-01-01

Human mesenchymal stem cells (hMSCs) have emerged as an important cell type in cell therapy and tissue engineering. In these applications, maintaining the therapeutic properties of hMSCs requires tight control of the culture environments and the structural cell organizations. Bioreactor systems are essential tools to achieve these goals in the clinical-scale expansion and tissue engineering applications. This review summarizes how different bioreactors provide cues to regulate the structure and the chemico-mechanical microenvironment of hMSCs with a focus on 3D organization. In addition to conventional bioreactors, recent advances in microfluidic bioreactors as a novel approach to better control the hMSC microenvironment are also discussed. These advancements highlight the key role of bioreactor systems in preserving hMSC's functional properties by providing dynamic and temporal regulation of in vitro cellular microenvironment. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

About ATMPs, SOPs and GMP: The Hurdles to Produce Novel Skin Grafts for Clinical Use

PubMed Central

Hartmann-Fritsch, Fabienne; Marino, Daniela; Reichmann, Ernst

2016-01-01

Background The treatment of severe full-thickness skin defects represents a significant and common clinical problem worldwide. A bio-engineered autologous skin substitute would significantly reduce the problems observed with today's gold standard. Methods Within 15 years of research, the Tissue Biology Research Unit of the University Children's Hospital Zurich has developed autologous tissue-engineered skin grafts based on collagen type I hydrogels. Those products are considered as advanced therapy medicinal products (ATMPs) and are routinely produced for clinical trials in a clean room facility following the guidelines for good manufacturing practice (GMP). This article focuses on hurdles observed for the translation of ATMPs from research into the GMP environment and clinical application. Results and Conclusion Personalized medicine in the field of rare diseases has great potential. However, ATMPs are mainly developed and promoted by academia, hospitals, and small companies, which face many obstacles such as high financial burdens. PMID:27781022

Mesenchymal Stem Cells for Cartilage Regeneration of TMJ Osteoarthritis

PubMed Central

Li, Hongyu; Xu, Xin; Ye, Ling; Zhou, Xuedong

2017-01-01

Temporomandibular joint osteoarthritis (TMJ OA) is a degenerative disease, characterized by progressive cartilage degradation, subchondral bone remodeling, synovitis, and chronic pain. Due to the limited self-healing capacity in condylar cartilage, traditional clinical treatments have limited symptom-modifying and structure-modifying effects to restore impaired cartilage as well as other TMJ tissues. In recent years, stem cell-based therapy has raised much attention as an alternative approach towards tissue repair and regeneration. Mesenchymal stem cells (MSCs), derived from the bone marrow, synovium, and even umbilical cord, play a role as seed cells for the cartilage regeneration of TMJ OA. MSCs possess multilineage differentiation potential, including chondrogenic differentiation as well as osteogenic differentiation. In addition, the trophic modulations of MSCs exert anti-inflammatory and immunomodulatory effects under aberrant conditions. Furthermore, MSCs combined with appropriate scaffolds can form cartilaginous or even osseous compartments to repair damaged tissue and impaired function of TMJ. In this review, we will briefly discuss the pathogenesis of cartilage degeneration in TMJ OA and emphasize the potential sources of MSCs and novel approaches for the cartilage regeneration of TMJ OA, particularly focusing on the MSC-based therapy and tissue engineering. PMID:29123550

Stem cells as biological heart pacemakers.

PubMed

Gepstein, Lior

2005-12-01

Abnormalities in the pacemaker function of the heart or in cardiac impulse conduction may result in the appearance of a slow heart rate, traditionally requiring the implantation of a permanent electronic pacemaker. In recent years, a number of experimental approaches have been developed in an attempt to generate biological alternatives to implantable electronic devices. These strategies include, initially, a number of gene therapy approaches (aiming to manipulate the expression of ionic currents or their modulators and thereby convert quiescent cardiomyocytes into pacemaking cells) and, more recently, the use of cell therapy and tissue engineering. The latter approach explored the possibility of grafting pacemaking cells, either derived directly during the differentiation of human embryonic stem cells or engineered from mesenchymal stem cells, into the myocardium. This review will describe each of these approaches, focusing mainly on the stem cell strategies, their possible advantages and shortcomings, as well as the avenues required to make biological pacemaking a clinical reality.

Current concepts in periodontal bioengineering

PubMed Central

Taba, M.; Jin, Q.; Sugai, J.V.; Giannobile, W.V.

2008-01-01

Repair of tooth supporting alveolar bone defects caused by periodontal and peri-implant tissue destruction is a major goal of reconstructive therapy. Oral and craniofacial tissue engineering has been achieved with limited success by the utilization of a variety of approaches such as cell-occlusive barrier membranes, bone substitutes and autogenous block grafting techniques. Signaling molecules such as growth factors have been used to restore lost tooth support because of damage by periodontal disease or trauma. This paper will review emerging periodontal therapies in the areas of materials science, growth factor biology and cell/gene therapy. Several different polymer delivery systems that aid in the targeting of proteins, genes and cells to periodontal and peri-implant defects will be highlighted. Results from preclinical and clinical trials will be reviewed using the topical application of bone morphogenetic proteins (BMP-2 and BMP-7) and platelet-derived growth factor-BB (PDGF) for periodontal and peri-implant regeneration. The paper concludes with recent research on the use of ex vivo and in vivo gene delivery strategies via gene therapy vectors encoding growth promoting and inhibiting molecules (PDGF, BMP, noggin and others) to regenerate periodontal structures including bone, periodontal ligament and cementum. PMID:16238610

Programmable probiotics for detection of cancer in urine

PubMed Central

Danino, Tal; Prindle, Arthur; Kwong, Gabriel A.; Skalak, Matthew; Li, Howard; Allen, Kaitlin; Hasty, Jeff; Bhatia, Sangeeta N.

2015-01-01

Rapid advances in the forward engineering of genetic circuitry in living cells has positioned synthetic biology as a potential means to solve numerous biomedical problems, including disease diagnosis and therapy. One challenge in exploiting synthetic biology for translational applications is to engineer microbes that are well tolerated by patients and seamlessly integrate with existing clinical methods. We use the safe and widely used probiotic Escherichia coli Nissle 1917 to develop an orally administered diagnostic that can noninvasively indicate the presence of liver metastasis by producing easily detectable signals in urine. Our microbial diagnostic generated a high-contrast urine signal through selective expansion in liver metastases (106-fold enrichment) and high expression of a lacZ reporter maintained by engineering a stable plasmid system. The lacZ reporter cleaves a substrate to produce a small molecule that can be detected in urine. E. coli Nissle 1917 robustly colonized tumor tissue in rodent models of liver metastasis after oral delivery but did not colonize healthy organs or fibrotic liver tissue. We saw no deleterious health effects on the mice for more than 12 months after oral delivery. Our results demonstrate that probiotics can be programmed to safely and selectively deliver synthetic gene circuits to diseased tissue microenvironments in vivo. PMID:26019220

Enhanced angiogenic effect of adipose-derived stromal cell spheroid with low-level light therapy in hindlimb ischemia mice

NASA Astrophysics Data System (ADS)

Park, In-Su; Ahn, Jin-Chul; Chung, Phil-Sang

2014-02-01

Adipose-derived stromal cells (ASCs) are attractive cell source for tissue engineering. However, one obstacle to this approach is that the transplanted ASC population can decline rapidly in the recipient tissue. The aim of this study was to investigate the effects of low-level laser therapy (LLLT) on transplanted human ASCs (hASCs) spheroid in a hindlimb ischemia animal model. LLLT, hASCs spheroid and hASCs spheroid transplantation with LLLT (spheroid + LLLT) were applied to the ischemic hindlimbs in athymic mice. The survival, differentiation and secretion of vascular endothelial growth (VEGF) of spheroid ASCs were evaluated by immunohistochemistry. The spheroid + LLLT group enhanced the tissue regeneration, including angiogenesis, compared with other groups. The spheroid contributed tissue regeneration via differentiation and secretion of growth factors. In the spheroid + LLLT group, the survival of spheroid hASCs was increased by the decreased apoptosis of spheroid hASCs in the ischemic hindlimb. The secretion of growth factors was stimulated in the spheroid + LLLT group compared with the ASCs group and spheroid group. These data suggest that LLLT is an effective biostimulator of spheroid hASCs in tissue regeneration that enhances the survival of ASCs and stimulates the secretion of growth factors in the ischemic hindlimb.

Redirecting adenovirus tropism by genetic, chemical, and mechanical modification of the adenovirus surface for cancer gene therapy.

PubMed

Yoon, A-Rum; Hong, Jinwoo; Kim, Sung Wan; Yun, Chae-Ok

2016-06-01

Despite remarkable advancements, clinical evaluations of adenovirus (Ad)-mediated cancer gene therapies have highlighted the need for improved delivery and targeting. Genetic modification of Ad capsid proteins has been extensively attempted. Although genetic modification enhances the therapeutic potential of Ad, it is difficult to successfully incorporate extraneous moieties into the capsid and the engineering process is laborious. Recently, chemical modification of the Ad surface with nanomaterials and targeting moieties has been found to enhance Ad internalization into the target by both passive and active mechanisms. Alternatively, external stimulus-mediated targeting can result in selective accumulation of Ad in the tumor and prevent dissemination of Ad into surrounding nontarget tissues. In the present review, we discuss various genetic, chemical, and mechanical engineering strategies for overcoming the challenges that hinder the therapeutic efficacy of Ad-based approaches. Surface modification of Ad by genetic, chemical, or mechanical engineering strategies enables Ad to overcome the shortcomings of conventional Ad and enhances delivery efficiency through distinct and unique mechanisms that unmodified Ad cannot mimic. However, although the therapeutic potential of Ad-mediated gene therapy has been enhanced by various surface modification strategies, each strategy still possesses innate limitations that must be addressed, requiring innovative ideas and designs.

Prospects for chimeric antigen receptor (CAR) γδ T cells: A potential game changer for adoptive T cell cancer immunotherapy.

PubMed

Mirzaei, Hamid Reza; Mirzaei, Hamed; Lee, Sang Yun; Hadjati, Jamshid; Till, Brian G

2016-10-01

Excitement is growing for therapies that harness the power of patients' immune systems to combat their diseases. One approach to immunotherapy involves engineering patients' own T cells to express a chimeric antigen receptor (CAR) to treat advanced cancers, particularly those refractory to conventional therapeutic agents. Although these engineered immune cells have made remarkable strides in the treatment of patients with certain hematologic malignancies, success with solid tumors has been limited, probably due to immunosuppressive mechanisms in the tumor niche. In nearly all studies to date, T cells bearing αβ receptors have been used to generate CAR T cells. In this review, we highlight biological characteristics of γδ T cells that are distinct from those of αβ T cells, including homing to epithelial and mucosal tissues and unique functions such as direct antigen recognition, lack of alloreactivity, and ability to present antigens. We offer our perspective that these features make γδ T cells promising for use in cellular therapy against several types of solid tumors, including melanoma and gastrointestinal cancers. Engineered γδ T cells should be considered as a new platform for adoptive T cell cancer therapy for mucosal tumors. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Mesenchymal Stem or Stromal Cells from Amnion and Umbilical Cord Tissue and Their Potential for Clinical Applications

PubMed Central

Lindenmair, Andrea; Hatlapatka, Tim; Kollwig, Gregor; Hennerbichler, Simone; Gabriel, Christian; Wolbank, Susanne; Redl, Heinz; Kasper, Cornelia

2012-01-01

Mesenchymal stem or stromal cells (MSC) have proven to offer great promise for cell-based therapies and tissue engineering applications, as these cells are capable of extensive self-renewal and display a multilineage differentiation potential. Furthermore, MSC were shown to exhibit immunomodulatory properties and display supportive functions through parakrine effects. Besides bone marrow (BM), still today the most common source of MSC, these cells were found to be present in a variety of postnatal and extraembryonic tissues and organs as well as in a large variety of fetal tissues. Over the last decade, the human umbilical cord and human amnion have been found to be a rich and valuable source of MSC that is bio-equivalent to BM-MSC. Since these tissues are discarded after birth, the cells are easily accessible without ethical concerns. PMID:24710543

Gene Therapy: A Paradigm Shift in Dentistry

PubMed Central

Siddique, Nida; Raza, Hira; Ahmed, Sehrish; Khurshid, Zohaib; Zafar, Muhammad Sohail

2016-01-01

Gene therapy holds a promising future for bridging the gap between the disciplines of medicine and clinical dentistry. The dynamic treatment approaches of gene therapy have been advancing by leaps and bounds. They are transforming the conventional approaches into more precise and preventive ones that may limit the need of using drugs and surgery. The oral cavity is one of the most accessible areas for the clinical applications of gene therapy for various oral tissues. The idea of genetic engineering has become more exciting due to its advantages over other treatment modalities. For instance, the body is neither subjected to an invasive surgery nor deep wounds, nor is it susceptible to systemic effects of drugs. The aim of this article is to review the gene therapy applications in the field of dentistry. In addition, therapeutic benefits in terms of treatment of diseases, minimal invasion and maximum outcomes have been discussed. PMID:27834914

Regenerative Rehabilitation: Combining Stem Cell Therapies and Activity-Dependent Stimulation.

PubMed

Moritz, Chet T; Ambrosio, Fabrisia

2017-07-01

The number of clinical trials in regenerative medicine is burgeoning, and stem cell/tissue engineering technologies hold the possibility of becoming the standard of care for a multitude of diseases and injuries. Advances in regenerative biology reveal novel molecular and cellular targets, with potential to optimize tissue healing and functional recovery, thereby refining rehabilitation clinical practice. The purpose of this review is to (1) highlight the potential for synergy between the fields of regenerative medicine and rehabilitation, a convergence of disciplines known as regenerative rehabilitation; (2) provide translational examples of regenerative rehabilitation within the context of neuromuscular injuries and diseases; and (3) offer recommendations for ways to leverage activity dependence via combined therapy and technology, with the goal of enhancing long-term recovery. The potential clinical benefits of regenerative rehabilitation will likely become a critical aspect in the standard of care for many neurological and musculoskeletal disorders.

Application of new optical coherence elastography to monitor the mineralization processing in bone tissue engineering constructs

NASA Astrophysics Data System (ADS)

Guan, Guangying; Song, Shaozhen; Huang, Zhihong; Yang, Ying

2015-03-01

Generation of functional tissue in vitro through tissue engineering technique is a promising direction to repair and replace malfunctioned organ and tissue in the modern medicine for various diseases which could not been treated well by conventional therapy. Similar to the embryo development, the generation of tissue in vitro is a highly dynamic processing. Obtaining the feedback of the processing real time is highly demanded. In this study, a new methodology has been explored aiming to monitor the morphological and mechanical property alteration of bone tissue engineering constructs simultaneously. Optical coherence elastography (OCE) equipped with a LDS V201 permanent magnet shaker and a modulated acoustic radiation force (ARF) to provide a vibration signal, has been used for the real time and non-destructive monitoring. A phantom construct system has been used to optimize the measurement conditions in which agar hydrogel with concentration from 0, 0.75 to 2% with/without hydroxyappatite particles have been injected to 3D porous poly (lactic acid) scaffolds to simulate the collagenous extracellular matrix (ECM) and mineralized ECM. The structural and elastography images of the constructs have clearly demonstrated the linear relation with the increased mechanical property versus the increase of agar concentration within the pores of the scaffolds. The MG63 bone cells seeded in the scaffolds and cultured for 4 weeks have been monitored by the established protocol exhibiting the increased mechanical strength in the pore wall where the ECM or mineralized ECM was assumed to be formed in comparison to empty pores. This study confirms that OCE-ARF could become a valuable tool in regenerative medicine to assess the biological events during in vitro culture and conditioning.

Endothelial Progenitor Cells as Shuttle of Anticancer Agents.

PubMed

Laurenzana, Anna; Margheri, Francesca; Chillà, Anastasia; Biagioni, Alessio; Margheri, Giancarlo; Calorini, Lido; Fibbi, Gabriella; Del Rosso, Mario

2016-10-01

Cell therapies are treatments in which stem or progenitor cells are stimulated to differentiate into specialized cells able to home to and repair damaged tissues. After their discovery, endothelial progenitor cells (EPCs) stimulated worldwide interest as possible vehicles to perform autologous cell therapy of tumors. Taking into account the tumor-homing properties of EPCs, two different approaches to control cancer progression have been pursued by combining cell-based therapy with gene therapy or with nanomedicine. The first approach is based on the possibility of engineering EPCs to express different transgenes, and the second is based on the capacity of EPCs to take up nanomaterials. Here we review the most important progress covering the following issues: the characterization of bona fide endothelial progenitor cells, their role in tumor vascularization and metastasis, and preclinical data about their use in cell-based tumor therapy, considering antiangiogenic, suicide, immune-stimulating, and oncolytic virus gene therapy. The mixed approach of EPC cell therapy and nanomedicine is discussed in terms of plasmonic-dependent thermoablation and molecular imaging.

Lingual Haematoma due to Tenecteplase in a Patient with Acute Myocardial Infarction

PubMed Central

Bal, Muhlis; Salturk, Ziya; Ateş, Ahmet Hakan; Yağcı, Serkan; Coşkun Bal, Gökçen

2013-01-01

The use of intravenous thrombolytic agents has revolutionised the treatment of acute myocardial infarction. However, the improvement in mortality rate achieved with these drugs is tempered by the risk of serious bleeding complications, including intracranial haemorrhage. Tenecteplase is a genetically engineered mutant tissue plasminogen activator. Haemorrhagic complications of tissue plasminogen activator (tPA) are well known. Compared to other tPAs, tenecteplase use leads to lower rates of bleeding complications. Here, we report a case of unusual site of spontaneous bleeding, intralingual haematoma during tenecteplase therapy following acute myocardial infarction, which caused significant upper airway obstruction and required tracheotomy to maintain the patient's airway. Clinical dilemmas related to securing the airway or reversing the effects of tissue plasminogen activator are discussed. PMID:23862086

Looking into the Future: Toward Advanced 3D Biomaterials for Stem-Cell-Based Regenerative Medicine.

PubMed

Liu, Zhongmin; Tang, Mingliang; Zhao, Jinping; Chai, Renjie; Kang, Jiuhong

2018-04-01

Stem-cell-based therapies have the potential to provide novel solutions for the treatment of a variety of diseases, but the main obstacles to such therapies lie in the uncontrolled differentiation and functional engraftment of implanted tissues. The physicochemical microenvironment controls the self-renewal and differentiation of stem cells, and the key step in mimicking the stem cell microenvironment is to construct a more physiologically relevant 3D culture system. Material-based 3D assemblies of stem cells facilitate the cellular interactions that promote morphogenesis and tissue organization in a similar manner to that which occurs during embryogenesis. Both natural and artificial materials can be used to create 3D scaffolds, and synthetic organic and inorganic porous materials are the two main kinds of artificial materials. Nanotechnology provides new opportunities to design novel advanced materials with special physicochemical properties for 3D stem cell culture and transplantation. Herein, the advances and advantages of 3D scaffold materials, especially with respect to stem-cell-based therapies, are first outlined. Second, the stem cell biology in 3D scaffold materials is reviewed. Third, the progress and basic principles of developing 3D scaffold materials for clinical applications in tissue engineering and regenerative medicine are reviewed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A review on the use of cell therapy in the treatment of tendon disease and injuries

PubMed Central

Sawadkar, Prasad; Mudera, Vivek

2014-01-01

Tendon disease and injuries carry significant morbidity worldwide in both athletic and non-athletic populations. It is estimated that tendon injuries account for 30%−50% of all musculoskeletal injuries globally. Current treatments have been inadequate in providing an accelerated process of repair resulting in high relapse rates. Modern concepts in tissue engineering and regenerative medicine have led to increasing interest in the application of cell therapy for the treatment of tendon disease. This review will explore the use of cell therapy, by bringing together up-to-date evidence from in vivo human and animal studies, and discuss the issues surrounding the safety and efficacy of its use in the treatment of tendon disease. PMID:25383170

Versatile CAR T-cells for cancer immunotherapy

PubMed Central

Cao, Jingjing; Neelalpu, Sattva S

2018-01-01

Chimeric antigen receptor (CAR) T-cell therapy has been clinically proven to efficiently combat haematological malignancies. However, continuous efforts are required to increase the specificity of CAR T-cells against tumour versus normal tissues, and are essential to improve their antitumour activity in solid tumours. This review summarises the structure of major CAR designs, and strategies to overcome immunosuppressive tumour microenvironment, and reduce toxicities. Along with reviewing currently available techniques that allow the elimination of CAR T-cells after they fulfil their desired functions, using suicide genes, drug elimination strategies are also introduced. A better understanding of the strengths and pitfalls of CAR T-cell therapy will provide fundamental knowledge for the improvement of engineered T-cell therapy in the near future. PMID:29628798

Bio-Engineering tissue and V.A.C. therapy: A new method for the treatment of extensive necrotizing infection in the diabetic foot.

PubMed

Armenio, Andrea; Cutrignelli, Daniela Anna; Nardulli, Maria Luisa; Maggio, Giulio; Memeo, Giuseppe; De Santis, Valerio; Giudice, Giuseppe; Ressa, Cosmo Maurizio

2017-01-01

The aim of the study is to compare the standard care for progressive necrotizing infection in diabetic foot with a treatment protocol based on the association between autologous fibroblast grafts and vacuum-assisted closure therapy (V.A.C.). A retrospective matched Case-Control study was carried out on 20 patients with diabetic foot infection, 10 treated with the standard care and 10 with our new protocol. Inclusion criteria were: acute diabetic foot necrosis (Wagner III and IV), ulcer size (30 to 80 cm2), tendon and bone exposure. Success in the treatment was evaluated as: percentage of healing at the 20th week, time of healing, deambulation, recurrence and major amputation rate. A 90% healing rate was observed after 20 weeks in the study group, compared to a 28.6% in the control group. The recurrence rate in the treated areas was 20% in the study group and 100% in the control group. None of the patients in either group required major amputations. We achieved very promising results by associating autologous fibroblasts grafts and V.A.C. therapy, in comparison with standard care. V.A.C. therapy seems to improve the growth rate of the fibroblasts, probably by sealing the wound and providing a moist environment following the fibroblast graft. The improved neoangiogenesis of the neo-dermis could explain the reduced recurrence rate of the study group. Despite the low number of patients involved and the retrospective nature of the analysis, this study showed a reliable, safe and cost-effective method of treating extensive infection in the diabetic foot. Bio-Engineered Tissue, Diabetic foot, Fibroblast graft, V.A.C.

Expansion in microcarrier-spinner cultures improves the chondrogenic potential of human early mesenchymal stromal cells.

PubMed

Lin, Youshan Melissa; Lim, Jessica Fang Yan; Lee, Jialing; Choolani, Mahesh; Chan, Jerry Kok Yen; Reuveny, Shaul; Oh, Steve Kah Weng

2016-06-01

Cartilage tissue engineering with human mesenchymal stromal cells (hMSC) is promising for allogeneic cell therapy. To achieve large-scale hMSC propagation, scalable microcarrier-based cultures are preferred over conventional static cultures on tissue culture plastic. Yet it remains unclear how microcarrier cultures affect hMSC chondrogenic potential, and how this potential is distinguished from that of tissue culture plastic. Hence, our study aims to compare the chondrogenic potential of human early MSC (heMSC) between microcarrier-spinner and tissue culture plastic cultures. heMSC expanded on either collagen-coated Cytodex 3 microcarriers in spinner cultures or tissue culture plastic were harvested for chondrogenic pellet differentiation with empirically determined chondrogenic inducer bone morphogenetic protein 2 (BMP2). Pellet diameter, DNA content, glycosaminoglycan (GAG) and collagen II production, histological staining and gene expression of chondrogenic markers including SOX9, S100β, MMP13 and ALPL, were investigated and compared in both conditions. BMP2 was the most effective chondrogenic inducer for heMSC. Chondrogenic pellets generated from microcarrier cultures developed larger pellet diameters, and produced more DNA, GAG and collagen II per pellet with greater GAG/DNA and collagen II/DNA ratios compared with that of tissue culture plastic. Moreover, they induced higher expression of chondrogenic genes (e.g., S100β) but not of hypertrophic genes (e.g., MMP13 and ALPL). A similar trend showing enhanced chondrogenic potential was achieved with another microcarrier type, suggesting that the mechanism is due to the agitated nature of microcarrier cultures. This is the first study demonstrating that scalable microcarrier-spinner cultures enhance the chondrogenic potential of heMSC, supporting their use for large-scale cell expansion in cartilage cell therapy. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

[Surgical Regeneration Therapy Using Myoblast Sheets for Severe Heart Failure].

PubMed

Sawa, Yoshiki

2017-01-01

Heart failure is a life-threatening disorder worldwide, and the current end-stage therapies for severe heart failure are replacement therapies such as ventricular-assist devices and heart transplantation. Although these therapies have been reported to be useful, there are many issues in terms of the durability, complications, limited donors, adverse effect of continuous administration of immunosuppressive agents, and high costs involved. Recently, regenerative therapy based on genetic, cellular, or tissue engineering techniques has gained attention as a new therapy to overcome the challenges encountered in transplantation medicine. We focused on skeletal myoblasts as the source of progenitor cells for autologous cell transplantation and the cell-sheet technique for site-specific implantation. In vitro studies have reported that myoblast sheets secrete cytoprotective and angiogenic cytokines such as hepatocyte growth factor (HGF). Additionally, in vivo studies using large and small animal models of heart failure, we have shown that myoblast sheets could improve diastolic and systolic performance and enhance angiogenesis and antifibrosis as well as the expression of several cytokines including HGF and vascular endothelial growth factor(VEGF) in the tissues at the transplanted site. Based on the results of these studies, we performed clinical trials using autologous myoblast sheets in ischemic cardiomyopathy (ICM) and dilated cardiomyopathy patients. Some patients showed left ventricular reverse remodeling and improved symptoms and exercise tolerance. Recently, multiple medical institutions including our institution successfully conducted an exploratory, uncontrolled, open-label phase II study in subjects with ICM to validate the efficacy and safety of autologous myoblast sheets. Moreover, as a novel cell source for regenerative medicine, our recent studies demonstrated that induced pluripotent stem cell-derived cardiomyocyte sheets showed electrical and microstructural homogeneity with heart tissue in vitro and in vivo, thus establishing proof of concept in small and large animal models of heart failure.

Molecular characterization of physis tissue by RNA sequencing.

PubMed

Paradise, Christopher R; Galeano-Garces, Catalina; Galeano-Garces, Daniela; Dudakovic, Amel; Milbrandt, Todd A; Saris, Daniel B F; Krych, Aaron J; Karperien, Marcel; Ferguson, Gabriel B; Evseenko, Denis; Riester, Scott M; van Wijnen, Andre J; Noelle Larson, A

2018-08-20

The physis is a well-established and anatomically distinct cartilaginous structure that is crucial for normal long-bone development and growth. Abnormalities in physis function are linked to growth plate disorders and other pediatric musculoskeletal diseases. Understanding the molecular pathways operative in the physis may permit development of regenerative therapies to complement surgically-based procedures that are the current standard of care for growth plate disorders. Here, we performed next generation RNA sequencing on mRNA isolated from human physis and other skeletal tissues (e.g., articular cartilage and bone; n = 7 for each tissue). We observed statistically significant enrichment of gene sets in the physis when compared to the other musculoskeletal tissues. Further analysis of these upregulated genes identified physis-specific networks of extracellular matrix proteins including collagens (COL2A1, COL6A1, COL9A1, COL14A1, COL16A1) and matrilins (MATN1, MATN2, MATN3), and signaling proteins in the WNT pathway (WNT10B, FZD1, FZD10, DKK2) or the FGF pathway (FGF10, FGFR4). Our results provide further insight into the gene expression networks that contribute to the physis' unique structural composition and regulatory signaling networks. Physis-specific expression profiles may guide ongoing initiatives in tissue engineering and cell-based therapies for treatment of growth plate disorders and growth modulation therapies. Furthermore, our findings provide new leads for therapeutic drug discovery that would permit future intervention through pharmacological rather than surgical strategies. Copyright © 2018 Elsevier B.V. All rights reserved.

Molecularly Imprinted Intelligent Scaffolds for Tissue Engineering Applications.

PubMed

Neves, Mariana I; Wechsler, Marissa E; Gomes, Manuela E; Reis, Rui L; Granja, Pedro L; Peppas, Nicholas A

2017-02-01

The development of molecularly imprinted polymers (MIPs) using biocompatible production methods enables the possibility to further exploit this technology for biomedical applications. Tissue engineering (TE) approaches use the knowledge of the wound healing process to design scaffolds capable of modulating cell behavior and promote tissue regeneration. Biomacromolecules bear great interest for TE, together with the established recognition of the extracellular matrix, as an important source of signals to cells, both promoting cell-cell and cell-matrix interactions during the healing process. This review focuses on exploring the potential of protein molecular imprinting to create bioactive scaffolds with molecular recognition for TE applications based on the most recent approaches in the field of molecular imprinting of macromolecules. Considerations regarding essential components of molecular imprinting technology will be addressed for TE purposes. Molecular imprinting of biocompatible hydrogels, namely based on natural polymers, is also reviewed here. Hydrogel scaffolds with molecular memory show great promise for regenerative therapies. The first molecular imprinting studies analyzing cell adhesion report promising results with potential applications for cell culture systems, or biomaterials for implantation with the capability for cell recruitment by selectively adsorbing desired molecules.

Accelerated Development of Supramolecular Corneal Stromal-Like Assemblies from Corneal Fibroblasts in the Presence of Macromolecular Crowders.

PubMed

Kumar, Pramod; Satyam, Abhigyan; Fan, Xingliang; Rochev, Yury; Rodriguez, Brian J; Gorelov, Alexander; Joshi, Lokesh; Raghunath, Michael; Pandit, Abhay; Zeugolis, Dimitrios I

2015-07-01

Tissue engineering by self-assembly uses the cells' secretome as a regeneration template and biological factory of trophic factors. Despite the several advantages that have been witnessed in preclinical and clinical settings, the major obstacle for wide acceptance of this technology remains the tardy extracellular matrix formation. In this study, we assessed the influence of macromolecular crowding (MMC)/excluding volume effect, a biophysical phenomenon that accelerates thermodynamic activities and biological processes by several orders of magnitude, in human corneal fibroblast (HCF) culture. Our data indicate that the addition of negatively charged galactose derivative (carrageenan) in HCF culture, even at 0.5% serum, increases by 12-fold tissue-specific matrix deposition, while maintaining physiological cell morphology and protein/gene expression. Gene analysis indicates that a glucose derivative (dextran sulfate) may drive corneal fibroblasts toward a myofibroblast lineage. Collectively, these results indicate that MMC may be suitable not only for clinical translation and commercialization of tissue engineering by self-assembly therapies, but also for the development of in vitro pathophysiology models.

Which cartilage is regenerated, hyaline cartilage or fibrocartilage? Non-invasive ultrasonic evaluation of tissue-engineered cartilage.

PubMed

Hattori, K; Takakura, Y; Ohgushi, H; Habata, T; Uematsu, K; Takenaka, M; Ikeuchi, K

2004-09-01

To investigate ultrasonic evaluation methods for detecting whether the repair tissue is hyaline cartilage or fibrocartilage in new cartilage regeneration therapy. We examined four experimental rabbit models: a spontaneous repair model (group S), a large cartilage defect model (group L), a periosteal graft model (group P) and a tissue-engineered cartilage regeneration model (group T). From the resulting ultrasonic evaluation, we used %MM (the maximum magnitude of the measurement area divided by that of the intact cartilage) as a quantitative index of cartilage regeneration. The results of the ultrasonic evaluation were compared with the histological findings and histological score. The %MM values were 61.1 +/- 16.5% in group S, 29.8 +/- 15.1% in group L, 36.3 +/- 18.3% in group P and 76.5 +/- 18.7% in group T. The results showed a strong similarity to the histological scoring. The ultrasonic examination showed that all the hyaline-like cartilage in groups S and T had a high %MM (more than 60%). Therefore, we could define the borderline between the two types of regenerated cartilage by the %MM.

Tissue chips - innovative tools for drug development and disease modeling.

PubMed

Low, L A; Tagle, D A

2017-09-12

The high rate of failure during drug development is well-known, however recent advances in tissue engineering and microfabrication have contributed to the development of microphysiological systems (MPS), or 'organs-on-chips' that recapitulate the function of human organs. These 'tissue chips' could be utilized for drug screening and safety testing to potentially transform the early stages of the drug development process. They can also be used to model disease states, providing new tools for the understanding of disease mechanisms and pathologies, and assessing effectiveness of new therapies. In the future, they could be used to test new treatments and therapeutics in populations - via clinical trials-on-chips - and individuals, paving the way for precision medicine. Here we will discuss the wide-ranging and promising future of tissue chips, as well as challenges facing their development.

Nanotechnology-Based Strategies for siRNA Brain Delivery for Disease Therapy.

PubMed

Zheng, Meng; Tao, Wei; Zou, Yan; Farokhzad, Omid C; Shi, Bingyang

2018-05-01

Small interfering RNA (siRNA)-based gene silencing technology has demonstrated significant potential for treating brain-associated diseases. However, effective and safe systemic delivery of siRNA into the brain remains challenging because of biological barriers such as enzymatic degradation, short circulation lifetime, the blood-brain barrier (BBB), insufficient tissue penetration, cell endocytosis, and cytosolic transport. Nanotechnology offers intriguing potential for addressing these challenges in siRNA brain delivery in conjunction with chemical and biological modification strategies. In this review, we outline the challenges of systemic delivery of siRNA-based therapy for brain diseases, highlight recent advances in the development and engineering of siRNA nanomedicines for various brain diseases, and discuss our perspectives on this exciting research field for siRNA-based therapy towards more effective brain disease therapy. Copyright © 2018 Elsevier Ltd. All rights reserved.

Three-Dimensional Human iPSC-Derived Artificial Skeletal Muscles Model Muscular Dystrophies and Enable Multilineage Tissue Engineering.

PubMed

Maffioletti, Sara Martina; Sarcar, Shilpita; Henderson, Alexander B H; Mannhardt, Ingra; Pinton, Luca; Moyle, Louise Anne; Steele-Stallard, Heather; Cappellari, Ornella; Wells, Kim E; Ferrari, Giulia; Mitchell, Jamie S; Tyzack, Giulia E; Kotiadis, Vassilios N; Khedr, Moustafa; Ragazzi, Martina; Wang, Weixin; Duchen, Michael R; Patani, Rickie; Zammit, Peter S; Wells, Dominic J; Eschenhagen, Thomas; Tedesco, Francesco Saverio

2018-04-17

Generating human skeletal muscle models is instrumental for investigating muscle pathology and therapy. Here, we report the generation of three-dimensional (3D) artificial skeletal muscle tissue from human pluripotent stem cells, including induced pluripotent stem cells (iPSCs) from patients with Duchenne, limb-girdle, and congenital muscular dystrophies. 3D skeletal myogenic differentiation of pluripotent cells was induced within hydrogels under tension to provide myofiber alignment. Artificial muscles recapitulated characteristics of human skeletal muscle tissue and could be implanted into immunodeficient mice. Pathological cellular hallmarks of incurable forms of severe muscular dystrophy could be modeled with high fidelity using this 3D platform. Finally, we show generation of fully human iPSC-derived, complex, multilineage muscle models containing key isogenic cellular constituents of skeletal muscle, including vascular endothelial cells, pericytes, and motor neurons. These results lay the foundation for a human skeletal muscle organoid-like platform for disease modeling, regenerative medicine, and therapy development. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Anti-EGFRvIII Chimeric Antigen Receptor-Modified T Cells for Adoptive Cell Therapy of Glioblastoma.

PubMed

Ren, Pei-Pei; Li, Ming; Li, Tian-Fang; Han, Shuang-Yin

2017-01-01

Glioblastoma (GBM) is one of the most devastating brain tumors with poor prognosis and high mortality. Although radical surgical treatment with subsequent radiation and chemotherapy can improve the survival, the efficacy of such regimens is insufficient because the GBM cells can spread and destroy normal brain structures. Moreover, these non-specific treatments may damage adjacent healthy brain tissue. It is thus imperative to develop novel therapies to precisely target invasive tumor cells without damaging normal tissues. Immunotherapy is a promising approach due to its capability to suppress the growth of various tumors in preclinical model and clinical trials. Adoptive cell therapy (ACT) using T cells engineered with chimeric antigen receptor (CAR) targeting an ideal molecular marker in GBM, e.g. epidermal growth factor receptor type III (EGFRvIII) has demonstrated a satisfactory efficacy in treating malignant brain tumors. Here we summarize the recent progresses in immunotherapeutic strategy using CAR-modified T cells oriented to EGFRvIII against GBM. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Engineered CRISPR Systems for Next Generation Gene Therapies.

PubMed

Pineda, Michael; Moghadam, Farzaneh; Ebrahimkhani, Mo R; Kiani, Samira

2017-09-15

An ideal in vivo gene therapy platform provides safe, reprogrammable, and precise strategies which modulate cell and tissue gene regulatory networks with a high temporal and spatial resolution. Clustered regularly interspaced short palindromic repeats (CRISPR), a bacterial adoptive immune system, and its CRISPR-associated protein 9 (Cas9), have gained attention for the ability to target and modify DNA sequences on demand with unprecedented flexibility and precision. The precision and programmability of Cas9 is derived from its complexation with a guide-RNA (gRNA) that is complementary to a desired genomic sequence. CRISPR systems open-up widespread applications including genetic disease modeling, functional screens, and synthetic gene regulation. The plausibility of in vivo genetic engineering using CRISPR has garnered significant traction as a next generation in vivo therapeutic. However, there are hurdles that need to be addressed before CRISPR-based strategies are fully implemented. Some key issues center on the controllability of the CRISPR platform, including minimizing genomic-off target effects and maximizing in vivo gene editing efficiency, in vivo cellular delivery, and spatial-temporal regulation. The modifiable components of CRISPR systems: Cas9 protein, gRNA, delivery platform, and the form of CRISPR system delivered (DNA, RNA, or ribonucleoprotein) have recently been engineered independently to design a better genome engineering toolbox. This review focuses on evaluating CRISPR potential as a next generation in vivo gene therapy platform and discusses bioengineering advancements that can address challenges associated with clinical translation of this emerging technology.

Genetically Engineered Autologous Cells for Antiangiogenic Therapy of Breast Cancer

DTIC Science & Technology

2004-07-01

consisted of a large, fragmented avascular center surrounded by a thin band of vascularized matrix material, itself covered by a capsule of connective tissue...contained dead cells that showed features of coagulation necrosis . The minimal inflammatory response consisted of neutrophils scattered within the...vascularize most likely contributed to the death (coagulation necrosis ) of implanted MSCs localized in the implant core and to the fragmentation of the

TALEN-engineered AR gene rearrangements reveal endocrine uncoupling of androgen receptor in prostate cancer

PubMed Central

Nyquist, Michael D.; Li, Yingming; Hwang, Tae Hyun; Manlove, Luke S.; Vessella, Robert L.; Silverstein, Kevin A. T.; Voytas, Daniel F.; Dehm, Scott M.

2013-01-01

Androgen receptor (AR) target genes direct development and survival of the prostate epithelial lineage, including prostate cancer (PCa). Thus, endocrine therapies that inhibit the AR ligand-binding domain (LBD) are effective in treating PCa. AR transcriptional reactivation is central to resistance, as evidenced by the efficacy of AR retargeting in castration-resistant PCa (CRPC) with next-generation endocrine therapies abiraterone and enzalutamide. However, resistance to abiraterone and enzalutamide limits this efficacy in most men, and PCa remains the second-leading cause of male cancer deaths. Here we show that AR gene rearrangements in CRPC tissues underlie a completely androgen-independent, yet AR-dependent, resistance mechanism. We discovered intragenic AR gene rearrangements in CRPC tissues, which we modeled using transcription activator-like effector nuclease (TALEN)-mediated genome engineering. This modeling revealed that these AR gene rearrangements blocked full-length AR synthesis, but promoted expression of truncated AR variant proteins lacking the AR ligand-binding domain. Furthermore, these AR variant proteins maintained the constitutive activity of the AR transcriptional program and a CRPC growth phenotype independent of full-length AR or androgens. These findings demonstrate that AR gene rearrangements are a unique resistance mechanism by which AR transcriptional activity can be uncoupled from endocrine regulation in CRPC. PMID:24101480

Implantable Sensors for Regenerative Medicine

PubMed Central

Klosterhoff, Brett S.; Tsang, Melissa; She, Didi; Ong, Keat Ghee; Allen, Mark G.; Willett, Nick J.; Guldberg, Robert E.

2017-01-01

The translation of many tissue engineering/regenerative medicine (TE/RM) therapies that demonstrate promise in vitro are delayed or abandoned due to reduced and inconsistent efficacy when implemented in more complex and clinically relevant preclinical in vivo models. Determining mechanistic reasons for impaired treatment efficacy is challenging after a regenerative therapy is implanted due to technical limitations in longitudinally measuring the progression of key environmental cues in vivo. The ability to acquire real-time measurements of environmental parameters of interest including strain, pressure, pH, temperature, oxygen tension, and specific biomarkers within the regenerative niche in situ would significantly enhance the information available to tissue engineers to monitor and evaluate mechanisms of functional healing or lack thereof. Continued advancements in material and fabrication technologies utilized by microelectromechanical systems (MEMSs) and the unique physical characteristics of passive magnetoelastic sensor platforms have created an opportunity to implant small, flexible, low-power sensors into preclinical in vivo models, and quantitatively measure environmental cues throughout healing. In this perspective article, we discuss the need for longitudinal measurements in TE/RM research, technical progress in MEMS and magnetoelastic approaches to implantable sensors, the potential application of implantable sensors to benefit preclinical TE/RM research, and the future directions of collaborative efforts at the intersection of these two important fields. PMID:27987300

Combined enzyme/prodrug treatment by genetically engineered AT-MSC exerts synergy and inhibits growth of MDA-MB-231 induced lung metastases.

PubMed

Matuskova, Miroslava; Kozovska, Zuzana; Toro, Lenka; Durinikova, Erika; Tyciakova, Silvia; Cierna, Zuzana; Bohovic, Roman; Kucerova, Lucia

2015-04-09

Metastatic spread of tumor cells remains a serious problem in cancer treatment. Gene-directed enzyme/prodrug therapy mediated by tumor-homing genetically engineered mesenchymal stromal cells (MSC) represents a promising therapeutic modality for elimination of disseminated cells. Efficacy of gene-directed enzyme/prodrug therapy can be improved by combination of individual systems. We aimed to define the combination effect of two systems of gene therapy mediated by MSC, and evaluate the ability of systemically administered genetically engineered mesenchymal stromal cells to inhibit the growth of experimental metastases derived from human breast adenocarcinoma cells MDA-MB-231/EGFP. Human adipose tissue-derived mesenchymal stromal cells (AT-MSC) were retrovirally transduced with fusion yeast cytosine deaminase::uracil phosphoribosyltransferase (CD::UPRT) or with Herpes simplex virus thymidine kinase (HSVtk). Engineered MSC were cocultured with tumor cells in the presence of prodrugs 5-fluorocytosin (5-FC) and ganciclovir (GCV). Combination effect of these enzyme/prodrug approaches was calculated. SCID/bg mice bearing experimental lung metastases were treated with CD::UPRT-MSC, HSVtk-MSC or both in combination in the presence of respective prodrug(s). Treatment efficiency was evaluated by EGFP-positive cell detection by flow cytometry combined with real-time PCR quantification of human cells in mouse organs. Results were confirmed by histological and immunohistochemical examination. We demonstrated various extent of synergy depending on tested cell line and experimental setup. The strongest synergism was observed on breast cancer-derived cell line MDA-MB-231/EGFP. Systemic administration of CD::UPRT-MSC and HSVtk-MSC in combination with 5-FC and GCV inhibited growth of MDA-MB-231 induced lung metastases. Combined gene-directed enzyme/prodrug therapy mediated by MSC exerted synergic cytotoxic effect and resulted in high therapeutic efficacy in vivo.

Tissue engineering: state of the art in oral rehabilitation

PubMed Central

SCHELLER, E. L.; KREBSBACH, P. H.; KOHN, D. H.

2009-01-01

SUMMARY More than 85% of the global population requires repair or replacement of a craniofacial structure. These defects range from simple tooth decay to radical oncologic craniofacial resection. Regeneration of oral and craniofacial tissues presents a formidable challenge that requires synthesis of basic science, clinical science and engineering technology. Identification of appropriate scaffolds, cell sources and spatial and temporal signals (the tissue engineering triad) is necessary to optimize development of a single tissue, hybrid organ or interface. Furthermore, combining the understanding of the interactions between molecules of the extracellular matrix and attached cells with an understanding of the gene expression needed to induce differentiation and tissue growth will provide the design basis for translating basic science into rationally developed components of this tissue engineering triad. Dental tissue engineers are interested in regeneration of teeth, oral mucosa, salivary glands, bone and periodontium. Many of these oral structures are hybrid tissues. For example, engineering the periodontium requires growth of alveolar bone, cementum and the periodontal ligament. Recapitulation of biological development of hybrid tissues and interfaces presents a challenge that exceeds that of engineering just a single tissue. Advances made in dental interface engineering will allow these tissues to serve as model systems for engineering other tissues or organs of the body. This review will begin by covering basic tissue engineering principles and strategic design of functional biomaterials. We will then explore the impact of biomaterials design on the status of craniofacial tissue engineering and current challenges and opportunities in dental tissue engineering. PMID:19228277

Tissue engineering: state of the art in oral rehabilitation.

PubMed

Scheller, E L; Krebsbach, P H; Kohn, D H

2009-05-01

More than 85% of the global population requires repair or replacement of a craniofacial structure. These defects range from simple tooth decay to radical oncologic craniofacial resection. Regeneration of oral and craniofacial tissues presents a formidable challenge that requires synthesis of basic science, clinical science and engineering technology. Identification of appropriate scaffolds, cell sources and spatial and temporal signals (the tissue engineering triad) is necessary to optimize development of a single tissue, hybrid organ or interface. Furthermore, combining the understanding of the interactions between molecules of the extracellular matrix and attached cells with an understanding of the gene expression needed to induce differentiation and tissue growth will provide the design basis for translating basic science into rationally developed components of this tissue engineering triad. Dental tissue engineers are interested in regeneration of teeth, oral mucosa, salivary glands, bone and periodontium. Many of these oral structures are hybrid tissues. For example, engineering the periodontium requires growth of alveolar bone, cementum and the periodontal ligament. Recapitulation of biological development of hybrid tissues and interfaces presents a challenge that exceeds that of engineering just a single tissue. Advances made in dental interface engineering will allow these tissues to serve as model systems for engineering other tissues or organs of the body. This review will begin by covering basic tissue engineering principles and strategic design of functional biomaterials. We will then explore the impact of biomaterials design on the status of craniofacial tissue engineering and current challenges and opportunities in dental tissue engineering.

From Microscale Devices to 3D Printing: Advances in Fabrication of 3D Cardiovascular Tissues.

PubMed

Borovjagin, Anton V; Ogle, Brenda M; Berry, Joel L; Zhang, Jianyi

2017-01-06

Current strategies for engineering cardiovascular cells and tissues have yielded a variety of sophisticated tools for studying disease mechanisms, for development of drug therapies, and for fabrication of tissue equivalents that may have application in future clinical use. These efforts are motivated by the need to extend traditional 2-dimensional (2D) cell culture systems into 3D to more accurately replicate in vivo cell and tissue function of cardiovascular structures. Developments in microscale devices and bioprinted 3D tissues are beginning to supplant traditional 2D cell cultures and preclinical animal studies that have historically been the standard for drug and tissue development. These new approaches lend themselves to patient-specific diagnostics, therapeutics, and tissue regeneration. The emergence of these technologies also carries technical challenges to be met before traditional cell culture and animal testing become obsolete. Successful development and validation of 3D human tissue constructs will provide powerful new paradigms for more cost effective and timely translation of cardiovascular tissue equivalents. © 2017 American Heart Association, Inc.

Implantation of In Vitro Tissue Engineered Muscle Repair Constructs and Bladder Acellular Matrices Partially Restore In Vivo Skeletal Muscle Function in a Rat Model of Volumetric Muscle Loss Injury

PubMed Central

Corona, Benjamin T.; Ward, Catherine L.; Baker, Hannah B.; Walters, Thomas J.

2014-01-01

The frank loss of a large volume of skeletal muscle (i.e., volumetric muscle loss [VML]) can lead to functional debilitation and presents a significant problem to civilian and military medicine. Current clinical treatment for VML involves the use of free muscle flaps and physical rehabilitation; however, neither are effective in promoting regeneration of skeletal muscle to replace the tissue that was lost. Toward this end, skeletal muscle tissue engineering therapies have recently shown great promise in offering an unprecedented treatment option for VML. In the current study, we further extend our recent progress (Machingal et al., 2011, Tissue Eng; Corona et al., 2012, Tissue Eng) in the development of tissue engineered muscle repair (TEMR) constructs (i.e., muscle-derived cells [MDCs] seeded on a bladder acellular matrix (BAM) preconditioned with uniaxial mechanical strain) for the treatment of VML. TEMR constructs were implanted into a VML defect in a tibialis anterior (TA) muscle of Lewis rats and observed up to 12 weeks postinjury. The salient findings of the study were (1) TEMR constructs exhibited a highly variable capacity to restore in vivo function of injured TA muscles, wherein TEMR-positive responders (n=6) promoted an ≈61% improvement, but negative responders (n=7) resulted in no improvement compared to nonrepaired controls, (2) TEMR-positive and -negative responders exhibited differential immune responses that may underlie these variant responses, (3) BAM scaffolds (n=7) without cells promoted an ≈26% functional improvement compared to uninjured muscles, (4) TEMR-positive responders promoted muscle fiber regeneration within the initial defect area, while BAM scaffolds did so only sparingly. These findings indicate that TEMR constructs can improve the in vivo functional capacity of the injured musculature at least, in part, by promoting generation of functional skeletal muscle fibers. In short, the degree of functional recovery observed following TEMR implantation (BAM+MDCs) was 2.3×-fold greater than that observed following implantation of BAM alone. As such, this finding further underscores the potential benefits of including a cellular component in the tissue engineering strategy for VML injury. PMID:24066899

Bioengineering of Artificial Lymphoid Organs.

PubMed

Nosenko, M A; Drutskaya, M S; Moisenovich, M M; Nedospasov, S A

2016-01-01

This review addresses the issue of bioengineering of artificial lymphoid organs.Progress in this field may help to better understand the nature of the structure-function relations that exist in immune organs. Artifical lymphoid organs may also be advantageous in the therapy or correction of immunodefficiencies, autoimmune diseases, and cancer. The structural organization, development, and function of lymphoid tissue are analyzed with a focus on the role of intercellular contacts and on the cytokine signaling pathways regulating these processes. We describe various polymeric materials, as scaffolds, for artificial tissue engineering. Finally, published studies in which artificial lymphoid organs were generated are reviewed and possible future directions in the field are discussed.

Bioengineering of Artificial Lymphoid Organs

PubMed Central

Nosenko, M. A.; Drutskaya, M. S.; Moisenovich, M. M.; Nedospasov, S. A.

2016-01-01

This review addresses the issue of bioengineering of artificial lymphoid organs.Progress in this field may help to better understand the nature of the structure-function relations that exist in immune organs. Artifical lymphoid organs may also be advantageous in the therapy or correction of immunodefficiencies, autoimmune diseases, and cancer. The structural organization, development, and function of lymphoid tissue are analyzed with a focus on the role of intercellular contacts and on the cytokine signaling pathways regulating these processes. We describe various polymeric materials, as scaffolds, for artificial tissue engineering. Finally, published studies in which artificial lymphoid organs were generated are reviewed and possible future directions in the field are discussed. PMID:27437136

Magnetic nanoparticle-based approaches to locally target therapy and enhance tissue regeneration in vivo

PubMed Central

Sensenig, Richard; Sapir, Yulia; MacDonald, Cristin; Cohen, Smadar; Polyak, Boris

2013-01-01

Magnetic-based systems utilizing superparamagnetic nanoparticles and a magnetic field gradient to exert a force on these particles have been used in a wide range of biomedical applications. This review is focused on drug targeting applications that require penetration of a cellular barrier as well as strategies to improve the efficacy of targeting in these biomedical applications. Another focus of this review is regenerative applications utilizing tissue engineered scaffolds prepared with the aid of magnetic particles, the use of remote actuation for release of bioactive molecules and magneto–mechanical cell stimulation, cell seeding and cell patterning. PMID:22994959

Regenerative endodontics: barriers and strategies for clinical translation.

PubMed

Mao, Jeremy J; Kim, Sahng G; Zhou, Jian; Ye, Ling; Cho, Shoko; Suzuki, Takahiro; Fu, Susan Y; Yang, Rujing; Zhou, Xuedong

2012-07-01

Regenerative endodontics has encountered substantial challenges toward clinical translation. The adoption by the American Dental Association of evoked pulp bleeding in immature permanent teeth is an important step for regenerative endodontics. However, there is no regenerative therapy for most endodontic diseases. Simple recapitulation of cell therapy and tissue engineering strategies that are under development for other organ systems has not led to clinical translation in regeneration endodontics. Recent work using novel biomaterial scaffolds and growth factors that orchestrate the homing of host endogenous cells represents a departure from traditional cell transplantation approaches and may accelerate clinical translation. Copyright © 2012 Elsevier Inc. All rights reserved.

Stem cells in dentistry--part I: stem cell sources.

PubMed

Egusa, Hiroshi; Sonoyama, Wataru; Nishimura, Masahiro; Atsuta, Ikiru; Akiyama, Kentaro

2012-07-01

Stem cells can self-renew and produce different cell types, thus providing new strategies to regenerate missing tissues and treat diseases. In the field of dentistry, adult mesenchymal stem/stromal cells (MSCs) have been identified in several oral and maxillofacial tissues, which suggests that the oral tissues are a rich source of stem cells, and oral stem and mucosal cells are expected to provide an ideal source for genetically reprogrammed cells such as induced pluripotent stem (iPS) cells. Furthermore, oral tissues are expected to be not only a source but also a therapeutic target for stem cells, as stem cell and tissue engineering therapies in dentistry continue to attract increasing clinical interest. Part I of this review outlines various types of intra- and extra-oral tissue-derived stem cells with regard to clinical availability and applications in dentistry. Additionally, appropriate sources of stem cells for regenerative dentistry are discussed with regard to differentiation capacity, accessibility and possible immunomodulatory properties. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Cell-Based Therapies in Lower Urinary Tract Disorders.

PubMed

Gopinath, Chaitanya; Ponsaerts, Peter; Wyndaele, Jean Jacques

2015-01-01

Cell-based therapy for the bladder has its beginnings in the 1990s with the successful isolation and culture of bladder smooth muscle cells. Since then, several attempts have been made to artificially implant native cell types and stem cell-derived cells into damaged bladders in the form of single-cell injectables or as grafts seeded onto artificial extracellular matrix. We critically examined in the literature the types of cells and their probable role as an alternative to non-drug-based, non-bowel-based graft replacement therapy in disorders of the urinary bladder. The limitations and plausible improvements to these novel therapies have also been discussed, keeping in mind an ideal therapy that could suit most bladder abnormalities arising out of varied number of disorders. In conclusion, muscle-derived cell types have consistently proven to be a promising therapy to emerge in the coming decade. However, tissue-engineered constructs have yet to prove their success in preclinical and long-term clinical setting.

A Standardized Rat Model of Volumetric Muscle Loss Injury for the Development of Tissue Engineering Therapies

PubMed Central

Wu, Xiaowu; Corona, Benjamin T.; Chen, Xiaoyu

2012-01-01

Abstract Soft tissue injuries involving volumetric muscle loss (VML) are defined as the traumatic or surgical loss of skeletal muscle with resultant functional impairment and represent a challenging clinical problem for both military and civilian medicine. In response, a variety of tissue engineering and regenerative medicine treatments are under preclinical development. A wide variety of animal models are being used, all with critical limitations. The objective of this study was to develop a model of VML that was reproducible and technically uncomplicated to provide a standardized platform for the development of tissue engineering and regenerative medicine solutions to VML repair. A rat model of VML involving excision of ∼20% of the muscle's mass from the superficial portion of the middle third of the tibialis anterior (TA) muscle was developed and was functionally characterized. The contralateral TA muscle served as the uninjured control. Additionally, uninjured age-matched control rats were also tested to determine the effect of VML on the contralateral limb. TA muscles were assessed at 2 and 4 months postinjury. VML muscles weighed 22.7% and 19.5% less than contralateral muscles at 2 and 4 months postinjury, respectively. These differences were accompanied by a reduction in peak isometric tetanic force (Po) of 28.4% and 32.5% at 2 and 4 months. Importantly, Po corrected for differences in body weight and muscle wet weights were similar between contralateral and age-matched control muscles, indicating that VML did not have a significant impact on the contralateral limb. Lastly, repair of the injury with a biological scaffold resulted in rapid vascularization and integration with the wound. The technical simplicity, reliability, and clinical relevance of the VML model developed in this study make it ideal as a standard model for the development of tissue engineering solutions for VML. PMID:23515319

Tissue engineering on the nanoscale: lessons from the heart.

PubMed

Fleischer, Sharon; Dvir, Tal

2013-08-01

Recognizing the limitations of biomaterials for engineering complex tissues and the desire for closer recapitulation of the natural matrix have led tissue engineers to seek new technologies for fabricating 3-dimensional (3D) cellular microenvironments. In this review, through examples from cardiac tissue engineering, we describe the nanoscale hallmarks of the extracellular matrix that tissue engineers strive to mimic. Furthermore, we discuss the use of inorganic nanoparticles and nanodevices for improving and monitoring the performance of engineered tissues. Finally, we offer our opinion on the main challenges and prospects of applying nanotechnology in tissue engineering. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mineralization Induction of Gingival Fibroblasts and Construction of a Sandwich Tissue-Engineered Complex for Repairing Periodontal Defects

PubMed Central

Wu, Mingxuan; Zhang, Yanning; Liu, Huijuan; Dong, Fusheng

2018-01-01

Background The ideal healing technique for periodontal tissue defects would involve the functional regeneration of the alveolar bone, cementum, and periodontal ligament, with new periodontal attachment formation. In this study, gingival fibroblasts were induced and a “sandwich” tissue-engineered complex (a tissue-engineered periodontal membrane between 2 tissue-engineered mineralized membranes) was constructed to repair periodontal defects. We evaluated the effects of gingival fibroblasts used as seed cells on the repair of periodontal defects and periodontal regeneration. Material/Methods Primitively cultured gingival fibroblasts were seeded bilaterally on Bio-Gide collagen membrane (a tissue-engineered periodontal membrane) or unilaterally on small intestinal submucosa segments, and their mineralization was induced. A tissue-engineered sandwich was constructed, comprising the tissue-engineered periodontal membrane flanked by 2 mineralized membranes. Periodontal defects in premolar regions of Beagles were repaired using the tissue-engineered sandwich or periodontal membranes. Periodontal reconstruction was compared to normal and trauma controls 10 or 20 days postoperatively. Results Periodontal defects were completely repaired by the sandwich tissue-engineered complex, with intact new alveolar bone and cementum, and a new periodontal ligament, 10 days postoperatively. Conclusions The sandwich tissue-engineered complex can achieve ideal periodontal reconstruction rapidly. PMID:29470454

Engineering complex tissues.

PubMed

Atala, Anthony; Kasper, F Kurtis; Mikos, Antonios G

2012-11-14

Tissue engineering has emerged at the intersection of numerous disciplines to meet a global clinical need for technologies to promote the regeneration of functional living tissues and organs. The complexity of many tissues and organs, coupled with confounding factors that may be associated with the injury or disease underlying the need for repair, is a challenge to traditional engineering approaches. Biomaterials, cells, and other factors are needed to design these constructs, but not all tissues are created equal. Flat tissues (skin); tubular structures (urethra); hollow, nontubular, viscus organs (vagina); and complex solid organs (liver) all present unique challenges in tissue engineering. This review highlights advances in tissue engineering technologies to enable regeneration of complex tissues and organs and to discuss how such innovative, engineered tissues can affect the clinic.

Design Approaches to Myocardial and Vascular Tissue Engineering.

PubMed

Akintewe, Olukemi O; Roberts, Erin G; Rim, Nae-Gyune; Ferguson, Michael A H; Wong, Joyce Y

2017-06-21

Engineered tissues represent an increasingly promising therapeutic approach for correcting structural defects and promoting tissue regeneration in cardiovascular diseases. One of the challenges associated with this approach has been the necessity for the replacement tissue to promote sufficient vascularization to maintain functionality after implantation. This review highlights a number of promising prevascularization design approaches for introducing vasculature into engineered tissues. Although we focus on encouraging blood vessel formation within myocardial implants, we also discuss techniques developed for other tissues that could eventually become relevant to engineered cardiac tissues. Because the ultimate solution to engineered tissue vascularization will require collaboration between wide-ranging disciplines such as developmental biology, tissue engineering, and computational modeling, we explore contributions from each field.

Dynamic culture yields engineered myocardium with near-adult functional output

PubMed Central

Jackman, Christopher P.; Carlson, Aaron L.; Bursac, Nenad

2016-01-01

Engineered cardiac tissues hold promise for cell therapy and drug development, but exhibit inadequate function and maturity. In this study, we sought to significantly improve the function and maturation of rat and human engineered cardiac tissues. We developed dynamic, free-floating culture conditions for engineering “cardiobundles”, 3-dimensional cylindrical tissues made from neonatal rat cardiomyocytes or human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) embedded in fibrin-based hydrogel. Compared to static culture, 2-week dynamic culture of neonatal rat cardiobundles significantly increased expression of sarcomeric proteins, cardiomyocyte size (~2.1-fold), contractile force (~3.5-fold), and conduction velocity of action potentials (~1.4-fold). The average contractile force per cross-sectional area (59.7 mN/mm2) and conduction velocity (52.5 cm/sec) matched or approached those of adult rat myocardium, respectively. The inferior function of statically cultured cardiobundles was rescued by transfer to dynamic conditions, which was accompanied by an increase in mTORC1 activity and decline in AMPK phosphorylation and was blocked by rapamycin. Furthermore, dynamic culture effects did not stimulate ERK1/2 pathway and were insensitive to blockers of mechanosensitive channels, suggesting increased nutrient availability rather than mechanical stimulation as the upstream activator of mTORC1. Direct comparison with phenylephrine treatment confirmed that dynamic culture promoted physiological cardiomyocyte growth rather than pathological hypertrophy. Optimized dynamic culture conditions also augmented function of human cardiobundles made reproducibly from cardiomyocytes derived from multiple hPSC lines, resulting in significantly increased contraction force (~2.5-fold) and conduction velocity (~1.4-fold). The average specific force of 23.2 mN/mm2 and conduction velocity of 25.8 cm/sec approached the functional metrics of adult human myocardium. In conclusion, we have developed a versatile methodology for engineering cardiac tissues with a near-adult functional output without the need for exogenous electrical or mechanical stimulation, and have identified mTOR signaling as an important mechanism for advancing tissue maturation and function in vitro. PMID:27723557

Dynamic culture yields engineered myocardium with near-adult functional output.

PubMed

Jackman, Christopher P; Carlson, Aaron L; Bursac, Nenad

2016-12-01

Engineered cardiac tissues hold promise for cell therapy and drug development, but exhibit inadequate function and maturity. In this study, we sought to significantly improve the function and maturation of rat and human engineered cardiac tissues. We developed dynamic, free-floating culture conditions for engineering "cardiobundles", 3-dimensional cylindrical tissues made from neonatal rat cardiomyocytes or human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) embedded in fibrin-based hydrogel. Compared to static culture, 2-week dynamic culture of neonatal rat cardiobundles significantly increased expression of sarcomeric proteins, cardiomyocyte size (∼2.1-fold), contractile force (∼3.5-fold), and conduction velocity of action potentials (∼1.4-fold). The average contractile force per cross-sectional area (59.7 mN/mm 2 ) and conduction velocity (52.5 cm/s) matched or approached those of adult rat myocardium, respectively. The inferior function of statically cultured cardiobundles was rescued by transfer to dynamic conditions, which was accompanied by an increase in mTORC1 activity and decline in AMPK phosphorylation and was blocked by rapamycin. Furthermore, dynamic culture effects did not stimulate ERK1/2 pathway and were insensitive to blockers of mechanosensitive channels, suggesting increased nutrient availability rather than mechanical stimulation as the upstream activator of mTORC1. Direct comparison with phenylephrine treatment confirmed that dynamic culture promoted physiological cardiomyocyte growth rather than pathological hypertrophy. Optimized dynamic culture conditions also augmented function of human cardiobundles made reproducibly from cardiomyocytes derived from multiple hPSC lines, resulting in significantly increased contraction force (∼2.5-fold) and conduction velocity (∼1.4-fold). The average specific force of 23.2 mN/mm 2 and conduction velocity of 25.8 cm/s approached the functional metrics of adult human myocardium. In conclusion, we have developed a versatile methodology for engineering cardiac tissues with a near-adult functional output without the need for exogenous electrical or mechanical stimulation, and have identified mTOR signaling as an important mechanism for advancing tissue maturation and function in vitro. Copyright © 2016 Elsevier Ltd. All rights reserved.

Anatomically shaped tissue-engineered cartilage with tunable and inducible anticytokine delivery for biological joint resurfacing

PubMed Central

Moutos, Franklin T.; Glass, Katherine A.; Compton, Sarah A.; Ross, Alison K.; Gersbach, Charles A.; Estes, Bradley T.

2016-01-01

Biological resurfacing of entire articular surfaces represents an important but challenging strategy for treatment of cartilage degeneration that occurs in osteoarthritis. Not only does this approach require anatomically sized and functional engineered cartilage, but the inflammatory environment within an arthritic joint may also inhibit chondrogenesis and induce degradation of native and engineered cartilage. The goal of this study was to use adult stem cells to engineer anatomically shaped, functional cartilage constructs capable of tunable and inducible expression of antiinflammatory molecules, specifically IL-1 receptor antagonist (IL-1Ra). Large (22-mm-diameter) hemispherical scaffolds were fabricated from 3D woven poly(ε-caprolactone) (PCL) fibers into two different configurations and seeded with human adipose-derived stem cells (ASCs). Doxycycline (dox)-inducible lentiviral vectors containing eGFP or IL-1Ra transgenes were immobilized to the PCL to transduce ASCs upon seeding, and constructs were cultured in chondrogenic conditions for 28 d. Constructs showed biomimetic cartilage properties and uniform tissue growth while maintaining their anatomic shape throughout culture. IL-1Ra–expressing constructs produced nearly 1 µg/mL of IL-1Ra upon controlled induction with dox. Treatment with IL-1 significantly increased matrix metalloprotease activity in the conditioned media of eGFP-expressing constructs but not in IL-1Ra–expressing constructs. Our findings show that advanced textile manufacturing combined with scaffold-mediated gene delivery can be used to tissue engineer large anatomically shaped cartilage constructs that possess controlled delivery of anticytokine therapy. Importantly, these cartilage constructs have the potential to provide mechanical functionality immediately upon implantation, as they will need to replace a majority, if not the entire joint surface to restore function. PMID:27432980

Current status of tissue engineering applied to bladder reconstruction in humans.

PubMed

Gasanz, C; Raventós, C; Morote, J

2018-01-11

Bladder reconstruction is performed to replace or expand the bladder. The intestine is used in standard clinical practice for tissue in this procedure. The complications of bladder reconstruction range from those of intestinal resection to those resulting from the continuous contact of urine with tissue not prepared for this contact. In this article, we describe and classify the various biomaterials and cell cultures used in bladder tissue engineering and reviews the studies performed with humans. We conducted a review of literature published in the PubMed database between 1950 and 2017, following the principles of the PRISM declaration. Numerous in vitro and animal model studies have been conducted, but only 18 experiments have been performed with humans, with a total of 169 patients. The current evidence suggests that an acellular matrix, a synthetic polymer with urothelial and autologous smooth muscle cells attached in vitro or stem cells would be the most practical approach for experimental bladder reconstruction. Bladder replacement or expansion without using intestinal tissue is still a challenge, despite progress in the manufacture of biomaterials and the development of cell therapy. Well-designed studies with large numbers of patients and long follow-up times are needed to establish an effective clinical translation and standardisation of the check-up functional tests. Copyright © 2017 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

3D Printing and Biofabrication for Load Bearing Tissue Engineering.

PubMed

Jeong, Claire G; Atala, Anthony

2015-01-01

Cell-based direct biofabrication and 3D bioprinting is becoming a dominant technological platform and is suggested as a new paradigm for twenty-first century tissue engineering. These techniques may be our next step in surpassing the hurdles and limitations of conventional scaffold-based tissue engineering, and may offer the industrial potential of tissue engineered products especially for load bearing tissues. Here we present a topically focused review regarding the fundamental concepts, state of the art, and perspectives of this new technology and field of biofabrication and 3D bioprinting, specifically focused on tissue engineering of load bearing tissues such as bone, cartilage, osteochondral and dental tissue engineering.

Preconditioning of skeletal myoblast-based engineered tissue constructs enables functional coupling to myocardium in vivo

PubMed Central

Treskes, Philipp; Neef, Klaus; Srinivasan, Sureshkumar Perumal; Halbach, Marcel; Stamm, Christof; Cowan, Douglas; Scherner, Maximilian; Madershahian, Navid; Wittwer, Thorsten; Hescheler, Jürgen; Wahlers, Thorsten; Choi, Yeong-Hoon

2015-01-01

Objective Skeletal myoblasts fuse to form functional syncytial myotubes as an integral part of the skeletal muscle. During this differentiation process, expression of proteins for mechanical and electrical integration is seized, which is a major drawback for the application of skeletal myoblasts in cardiac regenerative cell therapy, because global heart function depends on intercellular communication. Methods Mechanically preconditioned engineered tissue constructs containing neonatal mouse skeletal myoblasts were transplanted epicardially. A Y-chromosomal specific polymerase chain reaction (PCR) was undertaken up to 10 weeks after transplantation to confirm the presence of grafted cells. Histologic and electrophysiologic analyses were carried out 1 week after transplantation. Results Cells within the grafted construct expressed connexin 43 at the interface to the host myocardium, indicating electrical coupling, confirmed by sharp electrode recordings. Analyses of the maximum stimulation frequency (5.65 ± 0.37 Hz), conduction velocity (0.087 ± 0.011 m/s) and sensitivity for pharmacologic conduction block (0.736 ± 0.080 mM 1-heptanol) revealed effective electrophysiologic coupling between graft and host cells, although significantly less robust than in native myocardial tissue (maximum stimulation frequency, 11.616 ± 0.238 Hz, P<.001; conduction velocity, 0.300 ± 0.057 m/s, P<.01; conduction block, 1.983 ± 0.077 mM 1-heptanol, P<.001). Conclusions Although untreated skeletal myoblasts cannot couple to cardiomyocytes, we confirm that mechanical preconditioning enables transplanted skeletal myoblasts to functionally interact with cardio-myocytes in vivo and, thus, reinvigorate the concept of skeletal myoblast-based cardiac cell therapy. PMID:25439779

Autologous Minced Muscle Grafts: A Tissue Engineering Therapy for the Volumetric Loss of Skeletal Muscle

DTIC Science & Technology

2013-07-24

report that over the first 16 wk postinjury, MG transplantation 1) promotes remarkable regeneration of innervated muscle fibers within the defect area...i.e., de novo muscle fiber regeneration); 2) reduced evidence of chronic injury in the remaining muscle mass compared with nonrepaired muscles ...cated nuclei in 30% of fibers observed in nonrepaired muscles ); and 3) significantly improves net torque production (i.e., 55% of the functional deficit

Nitrogen fixation studies, lead detection in living plants, and solar wind analysis

NASA Technical Reports Server (NTRS)

Libby, W. F.

1971-01-01

Progress is reported for research on the following: (1) magnetically shielded test facility studies; (2) electrochemistry of B10C2H12, B9CH10(-), and preparation of tumor specific boron containing materials for use in cancer therapy; (3) histochemical method for determining lead in living plant tissue; (4) diamond cementing; (5) analysis of solar wind using the washings of lunar fines; and (6) environmental engineering.

Building Bridges: Leveraging Interdisciplinary Collaborations in the Development of Biomaterials to Meet Clinical Needs

PubMed Central

Fong, Eliza L.S.; Watson, Brendan M.; Kasper, F. Kurtis

2013-01-01

Our laboratory at Rice University has forged numerous collaborations with clinicians and basic scientists over the years to advance the development of novel biomaterials and modification of existing materials to meet clinical needs. This review highlights collaborative advances in biomaterials research from our laboratory in the areas of scaffold development, drug delivery and gene therapy, especially as related to applications in bone and cartilage tissue engineering. PMID:22821772

In vitro differentiation of human tooth germ stem cells into endothelial- and epithelial-like cells.

PubMed

Doğan, Ayşegül; Demirci, Selami; Şahin, Fikrettin

2015-01-01

Current clinical techniques in dental practice include stem cell and tissue engineering applications. Dental stem cells are promising primary cell source for mainly tooth tissue engineering. Interaction of mesenchymal stem cell with epithelial and endothelial cells is strictly required for an intact tooth morphogenesis. Therefore, it is important to investigate whether human tooth germ stem cells (hTGSCs) derived from wisdom tooth are suitable for endothelial and epithelial cell transformation in dental tissue regeneration approaches. Differentiation into endothelial and epithelial cell lineages were mimicked under defined conditions, confirmed by real time PCR, western blotting and immunocytochemical analysis by qualitative and quantitative methods. HUVECs and HaCaT cells were used as positive controls for the endothelial and epithelial differentiation assays, respectively. Immunocytochemical and western blotting analysis revealed that terminally differentiated cells expressed cell-lineage markers including CD31, VEGFR2, VE-Cadherin, vWF (endothelial cell markers), and cytokeratin (CK)-17, CK-19, EpCaM, vimentin (epithelial cell markers) in significant levels with respect to undifferentiated control cells. Moreover, high expression levels of VEGFR1, VEGFR2, VEGF, CK-18, and CK-19 genes were detected in differentiated endothelial and epithelial-like cells. Endothelial-like cells derived from hTGSCs were cultured on Matrigel, tube-like structure formations were followed as an indication for functional endothelial differentiation. hTGSCs successfully differentiate into various cell types with a broad range of functional abilities using an in vitro approach. These findings suggest that hTGSCs may serve a potential stem cell source for tissue engineering and cell therapy of epithelial and endothelial tissue. © 2014 International Federation for Cell Biology.

M13 phage-functionalized single-walled carbon nanotubes as nanoprobes for second near-infrared window fluorescence imaging of targeted tumors.

PubMed

Yi, Hyunjung; Ghosh, Debadyuti; Ham, Moon-Ho; Qi, Jifa; Barone, Paul W; Strano, Michael S; Belcher, Angela M

2012-03-14

Second near-infrared (NIR) window light (950-1400 nm) is attractive for in vivo fluorescence imaging due to its deep penetration depth in tissues and low tissue autofluorescence. Here we show genetically engineered multifunctional M13 phage can assemble fluorescent single-walled carbon nanotubes (SWNTs) and ligands for targeted fluorescence imaging of tumors. M13-SWNT probe is detectable in deep tissues even at a low dosage of 2 μg/mL and up to 2.5 cm in tissue-like phantoms. Moreover, targeted probes show specific and up to 4-fold improved uptake in prostate specific membrane antigen positive prostate tumors compared to control nontargeted probes. This M13 phage-based second NIR window fluorescence imaging probe has great potential for specific detection and therapy monitoring of hard-to-detect areas. © 2012 American Chemical Society

M13 phage-functionalized single-walled carbon nanotubes as nanoprobes for second near-infrared window fluorescence imaging of targeted tumors

PubMed Central

HAM, MOON-HO; QI, JIFA; BARONE, PAUL W.; STRANO, MICHAEL S.; BELCHER, ANGELA M.

2014-01-01

Second near-infrared (NIR) window light (950-1,400 nm) is attractive for in vivo fluorescence imaging due to its deep penetration depth in tissues and low tissue autofluorescence. Here we show genetically engineered multifunctional M13 phage can assemble fluorescent single-walled carbon nanotubes (SWNTs) and ligands for targeted fluorescence imaging of tumors. M13-SWNT probe is detectable in deep tissues even at a low dosage of 2 μg/mL and up to 2.5 cm in tissue-like phantoms. Moreover, targeted probes show specific and up to four-fold improved uptake in prostate specific membrane antigen positive prostate tumors compared to control non-targeted probes. This M13 phage-based second NIR window fluorescence imaging probe has great potential for specific detection and therapy monitoring of hard-to-detect areas. PMID:22268625