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Congenital heart diseases (CHD) are one of the most frequently diagnosed congenital disorders, affecting approximately 40,000 live births annually in the United States. Out of the new patients diagnosed with CHD yearly, an estimated 2,500 patients require a substitute, non-native conduit artery to replace structures congenitally absent or hypoplastic. Devices used for conduit replacement encounter limitations exhibiting varying degrees of stiffness, calcification, susceptibility to infection, thrombosis, and a lack of implant growth capacity. Here, we report the functionality of pentagalloyl glucose (PGG) stabilized decellularized valved bovine jugular vein conduit (PGG-DBJVC). The PGG-DBJVC tissues demonstrated mechanical properties comparable to native and glutaraldehyde fixed tissues, while exhibiting resistance to both collagenase and elastase enzymatic degradation. Subcutaneous implantation of tissues established their biocompatibility and resistance to calcification, while implantation in sheep in the pulmonary position demonstrated adequate implant functionality, and repopulation of host cells, without excessive inflammation. In conclusion, this PGG-DBJVC device could be a favorable replacement option for pediatric patients, reducing the need for reoperations required with current devices. Congenital Heart Disease (CHD) is a common congenital disorder affecting many newborns in the United States each year. The use of substitute conduit arteries is necessary for some patients with CHD who have missing or underdeveloped structures. Current conduit replacement devices have limitations, including stiffness, susceptibility to infection and thrombosis, and lack of implant growth capacity. Pentagalloyl glucose-stabilized bovine jugular vein valved tissue (PGG-DBJVC) offers a promising solution as it is resistant to calcification, and biocompatible. When implanted in rats and as pulmonary conduit replacement in sheep, the PGG-DBJVC demonstrated cellular infiltration without excessive inflammation, which could lead to remodeling and integration with host tissue and eliminate the need for replacement as the child grows. [Display omitted] [ABSTRACT FROM AUTHOR]

Adequate blood supply, a prerequisite for flap survival after grafting, makes angiogenesis of the flap the biggest problem to be solved. Researches have been conducted around vascularisation in correlation with flap grafting. However, bibliometric analyses systematically examining this research field are lacking. As such, we herein sought to conduct comprehensive comparative analyses of the contributions of different researchers, institutions, and countries to this research space in an effort to identify trends and hotspots in angiogenesis and vascularisation in the context of flap grafting. Publications pertaining to angiogenesis and vascularisation in the context of flap grafting were retrieved from the Web of Science Core Collection. References were then analysed and plotted using Microsoft Excel 2019, VOSviewer, and CiteSpace V. In total, 2234 papers that were cited 40 048 times (17.63 citations/paper) were included in this analysis. The greatest number of studies were from the United States, with these studies exhibiting both the highest number of citations (13 577) and the greatest overall H‐index (60). For The institutions that published the greatest number of studies were WENZHOU MEDICAL UNIVERSITY (681), while UNIVERSITY OF ERLANGEN NUREMBERG has the highest number of citations (1458), and SHANGHAI JIAO TONG UNIVERSITY holds the greatest overall H‐index (20). The greatest number of studies in this research space were published by Gao WY, while Horch RE was the most commonly cited researcher in the field. The VOS viewer software clustered relevant keywords into three clusters, with clusters 1, 2, 3, and 4 corresponding to studies in which the keywords 'anatomy', 'survival', 'transplantation', 'therapy' most frequently appeared. The most promising research hotspot‐related terms in this field included 'autophagy', 'oxidative stress', 'ischemia/reperfusion injury', which exhibited a most recent average appearing year (AAY) of 2017 and after. Generally speaking, the results of this analysis indicate that the number of articles exploring angiogenesis and flap‐related research has risen steadily, with the United States and China being the two countries publishing the greatest proportion of studies in this field. The overall focus of these studies has shifted away from 'infratest and tissue engineering' towards 'mechanisms'. In the future, particular attention should be paid to emerging research hotspots, which include 'ischemia/reperfusion injury' and treatments for promoting vascularization, such as 'platelet‐rich plasma'. In light of these findings, funding agencies should continue increasing their investment in the exploration of the concrete mechanisms and interventional therapeutic relevance of angiogenesis during flap transplantation. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases are the leading cause of morbidity and mortality in the United States. Cardiac tissue engineering is a direction in regenerative medicine that aims to repair various heart defects with the long-term goal of artificially rebuilding a full-scale organ that matches its native structure and function. Three-dimensional (3D) bioprinting offers promising applications through its layer-by-layer biomaterial deposition using different techniques and bio-inks. In this review, we will introduce cardiac tissue engineering, 3D bioprinting processes, bioprinting techniques, bio-ink materials, areas of limitation, and the latest applications of this technology, alongside its future directions for further innovation. [ABSTRACT FROM AUTHOR]

This article discusses ownership and property issues in three-dimensional (3D) bioprinting from the perspective of the tangible aspect of the technology. Many scholars have examined property issues in the intangible aspect of the technology, namely, the intellectual property issue. Since a major component of 3D bioprinting is cells taken from patients and donors, it is important to explore the right of ownership over the physical product, including cells used in the 3D bioprinting process and the 3D bioprinted organ itself. What is the extent of the donor's right over his/her cells taken for use in 3D bioprinting and even the 3D bioprinted organ - the product of those cells? For example, can the cell donor determine how his/her cells are used, or even who gets the 3D bioprinted organ? What rights does a person have over the commercial use of his/her cells or tissue for 3D bioprinting? [ABSTRACT FROM AUTHOR]

Background: Tremendous progress has been made in the field of cartilage repair and regeneration, particularly with tissue-engineering approaches. This study aims to estimate the global status and current trends in the field of cartilage tissue engineering. Methods: Publications from 2011 to 2020 on tissue engineering for cartilage repair and regeneration were retrieved from Web of Science Core Collection database. The source data were statistically evaluated based on the bibliometrics. In terms of visualized analysis, some bibliometric indicators such as bibliographic coupling, co-citation, co-authorship and co-occurrence analysis were performed by VOSviewer software, to investigate the research trends in tissue engineering for cartilage repair and regeneration. Results: In total, 3715 papers were included. Since 2011, the amount of issued papers and relative research interest (RRI) have grown by leaps and bounds globally. The United States was the biggest contributor to the research in this field, due to the greatest citation frequency, the highest H index and the strongest total link strength. Romania had the highest average citation for each. The journal Tissue Engineering Part A published most articles in this field. For institutions, the largest contributors were Shanghai Jiaotong University, University of California System and Sichuan University. Studies could all be grouped into four main clusters: study of biomaterial scaffolds, study of seeding cells and growth factors, experimental animal model and clinical study, and mechanism research. Conclusion: Great efforts should be put into the study of biomaterial scaffolds, seeding cells and growth factors, considered to be the next hot topics in cartilage tissue engineering. This findings provide collaborative insights and research orientation for academic researchers, surgeons and healthcare practitioners to a certain extent. [ABSTRACT FROM AUTHOR]

Most beef cattle in the United States start their lives on pasture and finish them in crowded feedlots, releasing hundreds of pounds of the greenhouse gases methane and nitrous oxide, before they are transported to a slaughterhouse, where they are killed and their bodies are sliced into steaks and ground into hamburgers. Until recently, the alternatives to this system were either meat produced in the less sustainable but more humane method of raising cattle solely on pasture and utilizing smaller-scale slaughterhouses or plant-based meat substitutes. The development of the first cultured beef burger in 2013, produced through tissue engineering, raised the possibility of a newer and better alternative. In this article, I use the example of cultured meat to argue that religion and technology are co-constitutive, that they shape and reshape each other, and that the intersection between religion and technology in meat production has had and continues to have a direct impact on animals raised for meat. Kosher meat, industrial or cultured, exemplifies the complexities in the relationship between religion, technology, and animals and will serve as the example throughout this article. [ABSTRACT FROM AUTHOR]

Many sports medicine physicians are currently considering introducing regenerative medicine into their practice. Regenerative medicine and the subclassification of orthobiologics are a complicated topic and have produced widely varying opinions. Although there is concern by government regulators, clinicians, scientists, patient advocacy organizations, and the media regarding the use of regenerative medicine products, there is also excitement about the potential benefits with growing evidence that certain regenerative medicine products are safe and potentially efficacious in treating musculoskeletal conditions. Sports medicine physicians would benefit from decision-making guidance about whether to introduce orthobiologics into their practice and how to do it responsibly. The purpose of this position statement is to provide sports medicine physicians with information regarding regenerative medicine terminology, a brief review of basic science and clinical studies within the subclassification of orthobiologics, regulatory considerations, and best practices for introducing regenerative medicine into clinical practice. This information will help sports medicine physicians make informed and responsible decisions about the role of regenerative medicine and orthobiologics in their practice. [ABSTRACT FROM AUTHOR]

In the burn treatment landscape, a variety of skin substitutes, human tissue-sourced products, and other products are being developed based on tissue engineering (ie, the combination of scaffolds, cells, and biologically active molecules into functional tissue with the goal of restoring, maintaining, or improving damaged tissue or whole organs) to provide dermal replacement, prevent infection, or prevent or mitigate scarring. Skin substitutes can have a variety of compositions (cellular vs acellular), origins (human, animal, or synthetically derived), and complexities (dermal or epidermal only vs composite). The regulation of tissue-engineered products in the United States occurs by one of several pathways established by the U.S. Food and Drug Administration, including a Biologics License Application (BLA), a 510(k) (Class I and Class II devices), Premarket Approval (Class III devices), or a human cells, tissues, and cellular and tissue-based products designation. Key differentiators among these regulatory classifications include the amount and type of data required to support a filing. For example, a BLA requires a clinical trial(s) and evaluation of safety and efficacy by the Center for Biologics Evaluation and Research. Applicable approved biological products must also comply with submission of advertising and promotional materials per regulations. This review provides a description of, and associated requirements for, the various regulatory pathways for the approval or clearance of tissue-engineered products. Some of the regulatory challenges for commercialization of such products for the treatment of burns will be explored. [ABSTRACT FROM AUTHOR]

Gastrointestinal disease burden continues to rise in the United States and worldwide. The development of bioengineering strategies to model gut injury or disease and to reestablish functional gut tissue could expand therapeutic options and improve clinical outcomes. Current approaches leverage a rapidly evolving gut bioengineering toolkit aimed at 1) de novo generation of gutlike tissues at multiple scales for microtissue models or implantable grafts and 2) regeneration of functional gut in vivo. Although significant progress has been made in intestinal organoid cultures and engineered tissues, development of predictive in vitro models and effective regenerative therapies remains challenging. In this review, we survey emerging bioengineering tools and recent methodological advances to identify current challenges and future opportunities in gut bioengineering for disease modeling and regenerative medicine. [ABSTRACT FROM AUTHOR]

Women's health concerns are generally underrepresented in basic and translational research, but reproductive health in particular has been hampered by a lack of understanding of basic uterine and menstrual physiology. Menstrual health is an integral part of overall health because between menarche and menopause, most women menstruate. Yet for tens of millions of women around the world, menstruation regularly and often catastrophically disrupts their physical, mental, and social well-being. Enhancing our understanding of the underlying phenomena involved in menstruation, abnormal uterine bleeding, and other menstruation-related disorders will move us closer to the goal of personalized care. Furthermore, a deeper mechanistic understanding of menstruation-a fast, scarless healing process in healthy individuals-will likely yield insights into a myriad of other diseases involving regulation of vascular function locally and systemically. We also recognize that many women now delay pregnancy and that there is an increasing desire for fertility and uterine preservation. In September 2018, the Gynecologic Health and Disease Branch of the Eunice Kennedy Shriver National Institute of Child Health and Human Development convened a 2-day meeting, "Menstruation: Science and Society" with an aim to "identify gaps and opportunities in menstruation science and to raise awareness of the need for more research in this field." Experts in fields ranging from the evolutionary role of menstruation to basic endometrial biology (including omic analysis of the endometrium, stem cells and tissue engineering of the endometrium, endometrial microbiome, and abnormal uterine bleeding and fibroids) and translational medicine (imaging and sampling modalities, patient-focused analysis of menstrual disorders including abnormal uterine bleeding, smart technologies or applications and mobile health platforms) to societal challenges in health literacy and dissemination frameworks across different economic and cultural landscapes shared current state-of-the-art and future vision, incorporating the patient voice at the launch of the meeting. Here, we provide an enhanced meeting report with extensive up-to-date (as of submission) context, capturing the spectrum from how the basic processes of menstruation commence in response to progesterone withdrawal, through the role of tissue-resident and circulating stem and progenitor cells in monthly regeneration-and current gaps in knowledge on how dysregulation leads to abnormal uterine bleeding and other menstruation-related disorders such as adenomyosis, endometriosis, and fibroids-to the clinical challenges in diagnostics, treatment, and patient and societal education. We conclude with an overview of how the global agenda concerning menstruation, and specifically menstrual health and hygiene, are gaining momentum, ranging from increasing investment in addressing menstruation-related barriers facing girls in schools in low- to middle-income countries to the more recent "menstrual equity" and "period poverty" movements spreading across high-income countries. [ABSTRACT FROM AUTHOR]

BACKGROUND: Patent is the most effective carrier of technological information. Preliminary study evaluates the strength of technology development in this field from the angle of patent quantity and quality, regional distribution of patent applicants, countries/regions of patent acceptance, patent applicants, inventors, and technical fields OBJECTIVE: To identify the hot sub-fields of tissue engineering through patent analysis, show their technological strength, reveal China’s level globally, and also clarify the competition between China and United States on the basis of previous research. METHODS: Combining qualitative analysis with quantitative analysis, the hot sub-fields of tissue engineering were identified based on the patsnap patent database. It analyzes from three perspectives: patent application, invention patent grant, and tripartite patent application, and demonstrates the scale and growth rate of technology development in the hot sub-fields from the perspective of the patent number and quality. RESULTS AND CONCLUSION: (1) There are four hot sub-fields in the field of tissue engineering: bone, skin, nerve, and cornea; each has its own characteristics. Bone tissue engineering is relatively large-scale. (2) The scale in the skin and nerve sub-fields is limited; corneal tissue engineering has not yet reached a certain amount of scale, but the output of technological achievements with high-quality and high-market value is high. (3) The technological scale and growth rate in the field of bone tissue engineering in China are much bigger and faster than those in the United States, and it also has accumulated a certain number of high-quality technological achievements. The technological scales of skin and nerve sub-fields in China exceed those in United States, and high-quality technological outputs are about twice that in United States. The technological scale and high-quality achievements in the corneal tissue engineering in China are far beyond those in the United States. (4) China’s high-market-value achievements in the hot sub-fields of tissue engineering are still far behind the United States. [ABSTRACT FROM AUTHOR]

Significant bone loss due to disease or severe injury can result in the need for a bone graft, with over 500,000 procedures occurring each year in the United States. However, the current standards for grafting, autografts and allografts, can result in increased patient morbidity or a high rate of failure respectively. An ideal alternative would be a biodegradable tissue engineered graft that fulfills the function of bone while promoting the growth of new bone tissue. We developed a prevascularized tissue engineered scaffold of electrospun biodegradable polymers PLLA and PDLA reinforced with hydroxyapatite, a mineral similar to that found in bone. A composite design was utilized to mimic the structure and function of human trabecular and cortical bone. These scaffolds were characterized mechanically and in vitro to determine osteoinductive and angioinductive properties. It was observed that further reinforcement is necessary for the scaffolds to mechanically match bone, but the scaffolds are successful at inducing the differentiation of mesenchymal stem cells into mature bone cells and vascular endothelial cells. Prevascularization was seen to have a positive effect on angiogenesis and cellular metabolic activity, critical factors for the integration of a graft. [ABSTRACT FROM AUTHOR]

Chronic venous disease (CVD) is the most common reported chronic condition in the United States, affecting more than 25 million Americans. Regardless of its high occurrence, current therapeutic options are far from ideal due to their palliative nature. For best treatment outcomes, challenging cases of chronic venous insufficiency (CVI) are treated by repair or replacement of venous valves. Regrettably, the success of venous valve transplant is dependent on the availability of autologous venous valves and hindered by the possibility of donor site complications and increased patient morbidity. Therefore, the use of alternative tissue sources to provide off-the-shelf venous valve replacements has potential to be extremely beneficial to the field of CVI. This manuscript demonstrates the capability of producing off-the-shelf fully functional venous valved extracellular matrix (ECM) scaffold conduits from bovine saphenous vein (SV), using an antigen removal (AR) method. AR ECM scaffolds maintained native SV structure-function relationships and associated venous valves function. Conversely, SDS decellularization caused significant changes to the collagen and elastin macromolecular structures, resulting in collagen fibril merging, elimination of fibril crimp, amalgaming collagen fibers and fragmentation of the inner elastic lamina. ECM changes induced by SDS decellularization resulted in significant venous valve dysfunction. Venous valved conduits generated using the AR approach have potential to serve as off-the-shelf venous valve replacements for CVI. Retention of the structure and composition of extracellular matrix (ECM) proteins within xenogeneic scaffolds for tissue engineering is of crucial importance, due to the undeniable effect ECM proteins can impose on repopulating cells and function of the resultant biomaterial. This manuscript demonstrates that alteration or elimination of ECM proteins via commonly utilized decellularization approach results in complete disruption of venous valve function. Conversely, retention of the delicate ECM structure and composition of native venous tissue, using an antigen removal tissue processing method, results in preservation of native venous valve function. Image, graphical abstract [ABSTRACT FROM AUTHOR]

BACKGROUND: Development of tissue engineering is of great social and economic significance. Understanding the basic research strength of China in the main subfields of tissue engineering can provide reference for the optimization of resources allocation and for the formulation of corresponding development strategies. OBJECTIVE: To evaluate the basic research strength of China in the main subfields of tissue engineering. METHODS: PubMed was searched for basic research and top basic research articles in the subfields of tissue engineering (including bone and cartilage, nerve, blood vessel, liver, skin, heart, and eye tissue engineering) in the world, the United States and China. By comparing with the global average and American, Chinese basic research strength in the main subfields of tissue engineering was evaluated with indicators including the number of papers, the growth rate of papers, and the number and proportion of top papers. RESULTS AND CONCLUSION: (1) The number of basic research papers pubIished by Chinese institutions in the subfields of bone and cartilage tissue engineering, nerve tissue engineering, vessel tissue engineering, liver tissue engineering, skin tissue engineering, cardiac tissue engineering and eye tissue engineering was 4 487, 3 551, 2 869, 1 328, 1 185, 1 088 and 689, respectively, accounting for 10%-15% of worldwide papers in corresponding subfields. The amount of papers published by Chinese institutions was nearly half of that published by institutions of the United States for the first five subfields, but only 32.1% and 37.8% of that published by institutions of the United States for the latter two subfields. (2) The annual growth rate of papers published by Chinese institutions was 19.3%, 19.5%, 18.2%, 14.6%, 21.8%, 19.6% and 19.6%, respectively, for the above seven subfrelds, all of which were obviously higher than that of the global average and the United States. (3) The number of top papers published by Chinese institutions was 36, 31, 33, 24, 15, 24 and 12, and the proportion of top papers published by Chinese institutions was 0.8%, 0.9%, 1.2%, 1.8%, 1.3%, 2.2% and 1.7%, respectively, all of which were obviously lower than that of the global average and the United States. (4) China has published relatively more papers on bone and cartilage tissue engineering, nerve tissue engineering and vessel tissue engineering, and relatively less papers on cardiac tissue engineering and eye tissue engineering. The amount of papers published by Chinese institutions has been growing rapidly in each of the seven main subfields of tissue engineering, with the speed of growing being obviously higher than that of the global average and the United States. China has published a certain amount of top papers in each of the seven subfields, while the proportion of top papers for China is obviously lower than that of the global average and the United States. [ABSTRACT FROM AUTHOR]

Injuries to articular cartilage and menisci can lead to cartilage degeneration that ultimately results in arthritis. Different forms of arthritis affect ~50 million people in the USA alone, and it is therefore crucial to identify methods that will halt or slow the progression to arthritis, starting with the initiating events of cartilage and meniscus defects. The surgical approaches in current use have a limited capacity for tissue regeneration and yield only short-term relief of symptoms. Tissue engineering approaches are emerging as alternatives to current surgical methods for cartilage and meniscus repair. Several cell-based and tissue-engineered products are currently in clinical trials for cartilage lesions and meniscal tears, opening new avenues for cartilage and meniscus regeneration. This Review provides a summary of surgical techniques, including tissue-engineered products, that are currently in clinical use, as well as a discussion of state-of-the-art tissue engineering strategies and technologies that are being developed for use in articular cartilage and meniscus repair and regeneration. The obstacles to clinical translation of these strategies are also included to inform the development of innovative tissue engineering approaches. [ABSTRACT FROM AUTHOR]

Advanced therapy medicinal products (ATMPs) are a fast-growing field of innovative therapies. The European Union (EU) and the United States (US) are fostering their development. For both regions, ATMPs fall under the regulatory framework of biological products, which determines the legal basis for their development. Sub-classifications of advanced therapies are different between regions, while in EU, there are four major groups, i.e., gene therapy, somatic cell therapy, tissue-engineered therapies, and combined advanced therapies; in US, the sub-classification covers two major groups of products, i.e., gene therapy and cellular therapy. The inclusion criteria that define a gene therapy are equivalent in both regions, and the exclusion criteria are directly related to the indications of the product. In the EU, there is a clear differentiation between cell- and tissue-based products regarding their classification as advanced therapies or coverage by other legal frameworks, whereas in US, there is a broader classification about whether or not these products can be categorized as biologic products. Both in EU and in US, in order to classify a cell- or a tissue-based product as an advanced therapy, it must be ensured that the processing of the cells implies a manipulation that alters their biological characteristics, although the term of manipulation in US differentiates between structural and non-structural cells and tissues. The regulatory terminology used to define ATMPs and their sub-classification reveals some differences between EU and US. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tissue engineering technology provides an effective medical means to solve the problems of organ donor insufficiency and tissue trauma reconstruction. OBJECTIVE: To provide information reference for researchers of tissue engineering through the analysis of the patents data to grasp the hotspot and core technologies of tissue engineering. METHODS: The information including the annual distribution of patents, priority countries, patentees, hotspot of technology and core patents by Excel after extracting the data by programming based on Derwent Innovations Index. RESULTS AND CONCLUSION: In the past decade, the number of patents in the field of tissue engineering is on a rise. The most prolific countries are the United States, China and Japan. Zhejiang University, Donghua University, and the University of California are the leading institutions. Two United States companies, TYCO HEALTHCARE GROUP LP and ETHICON INC, each have two of the 20 core patents. The market of the relevant tissue-engineered products is led by the United States. Scaffolds, tissue engineering technology and prosthesis are the hot areas of tissue engineering. Scaffold materials, extracellular matrix, drug delivery, construction technology, and devices are the core technologies in the field of tissue engineering. [ABSTRACT FROM AUTHOR]

The epidermis is a skin layer, which protects an organism from the different factors of external environment. Therefore, the fast and effective regeneration of epidermis is important. Potential materials used for epidermis regeneration may be polyurethane scaffolds in form of the thin permeable layers. One and main disadvantage of such polyurethane scaffolds are their lack of antibacterial and antifungal properties. The great proposition to improve antiseptic properties of polyurethane epidermis scaffolds is to modify them with the use of substances, which reveal antiseptic, antimicrobial, and/or antifungal properties like cinnamaldehyde (CA). The great advantage speaking in favor of this compound is the fact that it has been approved and concerned as generally safe by the Food and Drug Administration in the USA. In this paper was described the fabrication of antibacterial microporous polyurethane scaffolds (MPTLs) in a form of a thin layers by using solvent-casting/particulate-leaching technique combined with thermally induced phase separation. Obtained MPTLs were modified with CA at different concentrations (0.5–5%): to establish the most suitable antibacterial effect of the CA introduced into the MPTLs matrix. Obtained unmodified and CA-modified MPTLs were characterized by mechanical and physicochemical properties as well as by identification of their antibacterial performance. The performed studies revealed that the most relevant antimicrobial effect of CA-modified MPTLs was observed when the CA concentration was 3.5%. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) is an active ingredient that has attracted the attention of pharmaceutical companies. There are expectations that the market for it will grow in the next few years. A technology roadmap for hyaluronic acid and its derivatives market was built and analyzed. A roadmap is a prospective tool that allows the visualization of the evolution of a product or technology through time, revealing opportunities and providing greater safety for companies' and institutions' resource allocation. A search was conducted for patents that were granted or applied for in the USPTO database and for scientific articles in Science Direct database. The information was presented in categories in such a way that the evolution of the categories over time could be predicted. Analysis of the roadmap showed that the market is diverse with local and global companies developing patents in this sector. The main highlight is in the medical area, in which HA and its derivatives are widely used in the treatment of osteoarthritis, wound healing, cell regeneration, and tissue engineering. Major drug companies, such as Alergan, Klox Technologies, Fidia Pharma USA, and Cormedix have focused on HA. The roadmap indicated that, in the long run, the market's focus will be on cancer treatments with the development of less aggressive medicines, which have already been the research focus of companies such as Holy Stone Healthcare and DKFZ. China stands out as the country with the highest number of scientific articles and the USA as the country with the highest number of patents. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Treatment for end-stage liver failure is restricted by the critical shortage of donor organs; about 4000 people die in the USA while waiting for a transplantable organ. This situation has been a major driving force behind the rise of tissue engineering to build artificial tissues/organs. Recent advancements in creating transplantable liver grafts using decellularized liver scaffolds bring the field closer to clinical translation. However, a source of readily available and highly functional adult hepatocytes in adequate numbers for regenerative liver therapies still remains unclear. Here, we describe a new method to utilize discarded livers to make transplantable new liver grafts. We show that marginal donor livers damaged due to warm ischemia could be treated with machine perfusion to yield 39 million viable hepatocytes per gram of liver, similar to fresh livers, and these cells could be used to repopulate decellularized liver matrix (DLM) scaffolds to make transplantable liver grafts. The hepatocytes from recovered livers sustained their characteristic epithelial morphology while they exhibited slightly lower protein synthesis functions both in plate cultures and in recellularized liver grafts. The dampened protein synthesis was attributed to residual endoplasmic reticulum stress found in recovered cells. The results here represent a unique approach to reengineer transplantable liver grafts solely from discarded organs. [ABSTRACT FROM AUTHOR]

Background Aims: Advanced therapy medicinal products (ATMPs) are a class of biological products for human use that are based on gene, tissues or cells. ATMPs have peculiar characteristics when compared with traditional medicines. In this regard, long-term safety and efficacy follow-up systems of individuals treated with ATMPs have become necessary and may present unique challenges, because unlike conventional drugs and biologics, these products can exert their effects for years after administration. This work seeks to assess the requirements foreseen in the regulatory frameworks for the post-marketing authorization safety and efficacy surveillance for ATMPs in Brazil, European Union (EU), Japan and United States, which are some of the members of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use., Methods: We reviewed the scientific literature and official documents of regulatory agencies (RAs) in Brazil, the EU, Japan and the United States., Results and Conclusions: RAs in the EU, US and Japan have developed regulatory guidelines for the post-marketing surveillance of ATMPs. These guidelines aim at implementing surveillance plans for monitoring adverse events, including late ones, after marketing authorization. All the ATMPs authorized by the RAs studied, submitted some type of post-marketing requirement to supplement safety and efficacy data, according to the regulations and terminology used by those jurisdictions., Competing Interests: Declaration of Competing Interest The authors have no commercial, proprietary or financial interest in the products or companies described in this article., (Copyright © 2023 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

This article presents an editorial in which the authors discuss the use of emerging biotechnology in dental, oral, and craniofacial regenerative medicine. They comment on the innovations in these fields, which utilize tissue engineering, regeneration, and bioengineering techniques. Information is also presented on resource centers in the DOC Tissue Regeneration Consortium (DOCTRC).

Globally health care spending is increasing unsustainably. This is especially true of the treatment of musculoskeletal (MSK) disease where in the United States the MSK disease burden has doubled over the last 15 years. With an aging and increasingly obese population, the surge in MSK related spending is only set to worsen. Despite increased funding, research and attention to this pressing health need, little progress has been made toward novel therapies. Tissue engineering and regenerative medicine (TERM) strategies could provide the solutions required to mitigate this mounting burden. Biomaterial-based treatments in particular present a promising field of potentially cost-effective therapies. However, the translation of a scientific development to a successful treatment is fraught with difficulties. These barriers have so far limited translation of TERM science into clinical treatments. It is crucial for primary researchers to be aware of the barriers currently restricting the progression of science to treatments. Researchers need to act prospectively to ensure the clinical, financial, and regulatory hurdles which seem so far removed from laboratory science do not stall or prevent the subsequent translation of their idea into a treatment. The aim of this review is to explore the development and translation of new treatments. Increasing the understanding of these complexities and barriers among primary researchers could enhance the efficiency of biomaterial translation. J. Cell. Physiol. 230: 36-49, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In order to ease chronic shortages of transplantable human organs as well as circumvent the immune response of recipients, tissue engineers have seeded scaffolds with patients' stem cells that develop into functional replacements. Several individuals already have benefitted from lab-grown bladders and tracheas, and scientists have made promising advances in laboratory animals with far more complex organs such as hearts and kidneys. As this form of regenerative medicine moves from fantasy to reality, it will pose various puzzles for legal institutions. For instance, does tissue engineering merely amount to an innovative medical procedure subject to state regulation, or instead does it qualify as an interstate commercial activity governed by federal law? Will the outputs of this novel technique closely enough resemble human organs so that the Health Resources and Services Administration enjoys primary authority, or instead will they qualify as therapeutic products regulated by the Food and Drug Administration (FDA)? If subject to the supervision of the latter agency, then would lab-grown organs face licensure as biologics or medical devices, and how exactly would the FDA apply such requirements to tailor-made items? Collateral questions will arise in connection with tort law, payment, and patent protection. Unless existing systems for controlling medical technologies develop satisfactory answers to such concerns, they may create roadblocks to the realization of the full potential of tissue engineering. [ABSTRACT FROM AUTHOR]

The article offers information in the approaches in staging medicines utilizing different methods and surfaces in the U.S. It mentions the benefits of integrating therapeutics on thin films. Moreover, ways on how therapeutics can be tailored according to develop new therapeutic regiments are also stated.

Progress in understanding the role of bone morphogenetic proteins (BMPs) in craniofacial and tooth development and the demonstration of stem cells in periodontal ligament have set the stage for periodontal regenerative therapy and tissue engineering. Furthermore, recent approval by the Food and Drug Administration of recombinant human BMPs for accelerating bone fusion in slow-healing fractures indicates that this protein family may prove useful in designing regenerative treatments in periodontics. In the near term, these advances are likely to be applied to periodontal surgery; ultimately, they may facilitate approaches to regenerating whole lost periodontal structures. [ABSTRACT FROM AUTHOR]

Advanced therapies constitute one of the most complex, organizational, and regulatory areas currently approached by clinical researchers in order to explore new therapeutic applications. Basic scientists and clinicians trying to implement cell therapies into clinical practice, may feel overwhelmed by the apparently endless regulatory requirements that apply. However, regulatory agencies have primary responsibility on patient safety and law enforcement are, and should be, their main considerations. Cell- and tissuebased therapies have the potential to treat many conditions, where present conventional treatments are inadequate. The current approach to cell- and tissue- based therapy development requires using good manufacturing production facilities through master and working cell banks. Facilities need to be purpose-designed and accredited by their national medicinal regulatory body and production scientists need to work in close tandem with quality assurances and ethics committees to absolutely ensure the safety of this cellular products. [ABSTRACT FROM AUTHOR]

Abstract: The Food and Drug Administration (FDA) has approved of a variety of hard and soft tissue lasers for use in the dental treatment of adults and children. Because dental lasers boast unique absorption characteristics, they are used to perform specific dental procedures and improve its characteristics by using some of lasers in prevention and conditioning of enamel as Nd:yag and Er:yag lasers. Lasers have been tested to improve enamel properties in order to enhance its resistance to demineralization. Since the 1960s, when associated with fluoride by special wavelengths of some lasers. This study evaluated the influence of both Er: YAG and Nd: YAG laser irradiation on deciduous enamel demineralization. The Nd: YAG laser wavelength of 1064nm exhibits strong thermal effect in soft dental tissue because of its appropriate absorption characteristics, is also efficient in the increase of the enamel resistance and play an important role in the prevention of dental caries by forming enamel granules of variable sizes. Er:YAG. Its emitted wavelength of 2940nm matches exactly the maximal absorption in water which play main role in conditioning of Hydroxyapatite nanorods of enamel. [Copyright &y& Elsevier]

Rotator cuff tears represent the most common shoulder injuries in the United States. The debilitating effect of this degenerative condition coupled with the high incidence of failure associated with existing graft choices underscores the clinical need for alternative grafting solutions. The 2 critical design criteria for the ideal tendon graft would require the graft to not only exhibit physiologically relevant mechanical properties but also be able to facilitate functional graft integration by promoting the regeneration of the native tendon-to-bone interface. Centered on these design goals, this review will highlight current approaches to functional and integrative tendon repair. In particular, the application of biomimetic design principles through the use of nanofiber- and nanocomposite-based scaffolds for tendon tissue engineering will be discussed. This review will begin with nanofiber-based approaches to functional tendon repair, followed by a section highlighting the exciting research on tendon-to-bone interface regeneration, with an emphasis on implementation of strategic biomimicry in nanofiber scaffold design and the concomitant formation of graded multi-tissue systems for integrative soft-tissue repair. This review will conclude with a summary and discussion of future directions. [Copyright &y& Elsevier]

Aim The primary objective of this study was to clinically and histologically evaluate periodontal wound healing/regeneration following surgical implantation of recombinant human growth/differentiation factor-5 (rh GDF-5) adsorbed onto a particulate β-tricalcium phosphate (β- TCP) carrier rh GDF-5/β- TCP into periodontal defects in man. Material & Methods Twenty chronic periodontitis patients, each with at least one tooth scheduled for extraction exhibiting a probing depth ≥6 mm and an associated intra-bony defect ≥4 mm participated in the study upon written informed consent. Subjects (one defect/patient) were randomized to receive open flap debridement ( OFD) + rh GDF-5/β- TCP (n = 10) or OFD alone (control; n = 10). Block biopsies of the defect sites were collected at 6 months post-surgery and prepared for the histological evaluation. Two masked examiners evaluated the deepest aspect of each defect site relative to bone (height/area), periodontal ligament ( PDL) and cementum regeneration, and residual β- TCP. Results Sites receiving rh GDF-5/β- TCP showed numerically greater PD reduction (3.7 ± 1.2 versus 3.1 ± 1.8 mm; p = 0.26), less gingival recession (0.5 ± 0.8 versus 1.4 ± 1.0 mm; p < 0.05) and greater clinical attachment level ( CAL) gain (3.2 ± 1.7 versus 1.7 ± 2.2 mm; p = 0.14) at the deepest aspect of the defect compared with OFD alone. One biopsy in the rh GDF-5/β- TCP and four biopsies in the OFD group were deemed as not evaluable. Histologically, bone regeneration height was almost threefold greater for the rh GDF-5/β- TCP treatment compared with OFD alone (2.19 ± 1.59 versus 0.81 ± 1.02 mm; p = 0.08). Similarly an almost twofold increase was observed for PDL (2.16 ± 1.43 versus 1.23 ± 1.07 mm; p = 0.26), cementum (2.16 ± 1.43 versus 1.23 ± 1.07 mm; p = 0.26) and bone regeneration area (0.74 ± 0.69 versus 0.32 ± 0.47 mm2; p = 0.14). Root resorption/ankylosis was not observed. Residual β- TCP occupied 8.4 ± 11.5% of the area of interest in biopsies of patients receiving rh GDF-5/β- TCP. Five biopsies (one rh GDF-5/β- TCP, four OFD) were deemed unsuitable to allow a meaningful histological or histometrical evaluation. Conclusions Descriptive statistics showed greater PD reduction and CAL gain, and greater alveolar bone regeneration and periodontal regeneration at sites that received rh GDF-5/β- TCP compared to control. However, these differences were not statistically significant. Future studies with larger sample sizes will have to be conducted to verify these findings. [ABSTRACT FROM AUTHOR]

Abstract: With over 500,000 coronary artery bypass grafts (CABG) performed annually in the United States alone, there is a significant clinical need for a small diameter tissue engineered vascular graft. A principle goal in tissue engineering is to develop materials and growth conditions that encourage appropriate recellularization and extracellular matrix formation in vivo. A particular challenge in vascular engineering results from the inability of adult cells to produce elastin, as its expression is developmentally limited. We investigated factors to stimulate elastogenesis in vitro, and found that heparin treatment of adult human vascular smooth muscle cells promoted the formation of elastic fibers. This effect was heparin-specific, and dependent on cell density and growth state. We then applied this information to a silk-based construct, and found that immobilized heparin showed essentially identical biological effects to that of soluble heparin. These findings indicate that heparinized vascular grafts may promote elastin formation and regulate restenosis, in addition to heparin''s well-established antithrombotic properties. Given the increase in elastin mRNA level and the increase in extracellular elastin present, our data suggests that there may be multiple levels of elastin regulation that are mediated by heparin treatment. [Copyright &y& Elsevier]

Background: There are currently several approaches being pursued to treat focal defects of articular cartilage, each having specific advantages or challenges. A single-stage procedure that uses autologous cartilage fragments, Cartilage Autograft Implantation System (CAIS), is being evaluated in patients and may offer a clinically effective option.Purpose: To establish the safety of CAIS and to test whether CAIS improves quality of life by using standardized outcomes assessment tools.Study Design: Randomized controlled trial; Level of evidence, 2.Methods: Patients (n = 29) were randomized (1:2) with the intent to treat with either a control (microfracture [MFX]) or an experimental (CAIS) procedure. Patients were followed at predetermined time points for 2 years using several standardized outcomes assessment tools (SF-36, International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS]). Magnetic resonance imaging was performed at baseline, 3 weeks, and 6, 12, and 24 months.Results: Lesion size and International Cartilage Repair Society (ICRS) grade were similar in both groups. General outcome measures (eg, physical component score of the SF-36) indicated an overall improvement in both groups, and no differences in the number of adverse effects were noted in comparisons between the CAIS and MFX groups. The IKDC score of the CAIS group was significantly higher (73.9 ± 14.72 at 12 months and 82.95 ± 14.88 at 24 months) compared with the MFX group (57.78 ± 18.31 at 12 months and 59.5 ± 13.44 at 24 months). Select subdomains (4/5) in the KOOS instrument were significantly different at 12 and 18 months, and all subdomains (Symptoms and Stiffness, Pain, Activities of Daily Living, Sports and Recreation, Knee-related Quality of Life) were significantly increased at 24 months in CAIS with scores of 88.47 ± 11.68, 90.64 ± 7.87, 97.29 ± 3.8, 78.16 ± 22.06, and 69 ± 23.15 compared with 75 ± 9.31, 78.94 ± 13.73, 89.46 ± 8.13, 51.67 ± 26.01, and 37.15 ± 21.67 in the MFX group. These significant improvements were maintained at 24 months in both IKDC and KOOS. Qualitative analysis of the imaging data did not note differences between the 2 groups in fill of the graft bed, tissue integration, or presence of subchondral cysts. Patients treated with MFX had a significantly higher incidence of intralesional osteophyte formation (54% and 70% of total number of lesions treated) at 6 and 12 months when compared with CAIS (8% and 25% of total number of lesions treated).Conclusion: The first clinical experience in using CAIS for treating patients with focal chondral defects indicates that it is a safe, feasible, and effective method that may improve long-term clinical outcomes. [ABSTRACT FROM AUTHOR]

Recombinant human bone morphogenetic protein-2 (rhBMP2) has been shown to induce both in vitro osteogenic differentiation and in vivo bone formation, with the capacity of rhBMP2 to elicit the repair of numerous bony defects (calvaria, spinal fusion, femora, and so on) well documented. In addition, rhBMP2 has been approved by the Food and Drug Administration (FDA) for selected human indications. Despite the fact that healing is often achieved, the challenge still remains to optimize the therapeutic use of rhBMP2. One avenue may be through the combination of rhBMP2 with stem cells capable of osteogenic differentiation. This study investigates the ability of rhBMP2 at various doses in combination with human adipose-derived stem cells (ASCs) to heal critical-sized rat segmental femoral defects. For this, different doses of rhBMP2 were incorporated with apatite-coated porous poly( l-lactide-co- dl-lactide) (70 : 30) (PLDLA) scaffolds, seeded with ASCs, and implanted into athymic rats. After 8 weeks, all implants were harvested and processed for bone formation using micro computed tomography (microCT) analysis and histology. Despite the findings that indicate no adverse effect of the apatite surface on ASC osteogenesis, no significant difference in bone formation could be qualitatively or quantitatively determined upon the implantation of ASC-seeded scaffolds absorbed to increasing doses of rhBMP2. Such results would suggest that the presence of ASCs within rhBMP2-absorbed scaffolds does not improve the bone-forming ability of the construct and that the formation of bone may be driven by the rhBMP2 alone. Based on these results, the addition of ASCs to rhBMP2-treated scaffolds may provide no significant advantage in terms of the ability to heal bone. [ABSTRACT FROM AUTHOR]

This study provides an insight into the difficulties companies encounter in transposing basic science into commercially viable healthcare technologies, focusing on the issue of establishing a dominant supply model within a highly regulated market. The core issue is how to scale-up customised scientific processes into products able to supply wider and possibly mass markets. In tracing the development of approaches to scaling-up, the paper highlights the influence regulatory regimes have on high technology regulated products and services. The paper details the implications of two contrasting supply initiatives towards operationalising tissue engineering, based on differences in regulatory regimes between Europe and the USA. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Under a Food and Drug Administration directive, we examined definite long-term safety and efficacy aspects of an engineered diaphragmatic tendon graft as a regulatory prerequisite for clinical trials. Methods: Newborn lambs (N = 27) underwent partial diaphragmatic replacement with a Teflon patch, a composite acellular bioprosthesis, or the same bioprosthesis seeded with autologous amniotic mesenchymal stem cells processed under Good Manufacturing Practice guidelines. Multiple safety and efficacy analyses were performed at different time points up to 14 months of age (ovine adulthood). Results: There was no mortality. None of the blood tests or full body autopsy specimens showed any abnormality. There was a significantly higher failure rate in animals that received an acellular bioprosthetic graft vs an engineered graft, with no significant differences between Teflon and acellular bioprosthetic implants. Tensile strength and total collagen levels were significantly higher in engineered grafts than in acellular bioprosthetic grafts. On histology, lysozyme and myeloperoxidase stainings were unremarkable in all grafts. Conclusions: Diaphragmatic repair with a clinically viable autologous tendon engineered with amniotic mesenchymal stem cells leads to improved outcomes when compared with an equivalent acellular bioprosthesis, with no local or systemic adverse effects. Clinical trials of engineered diaphragmatic repair appear practicable within regulatory guidelines. [ABSTRACT FROM AUTHOR]

The article presents several studies relating to orthopaedic medicine in the U.S. It includes the influence of the mechanical environment on tendon and ligament structure and function and the effects of mechanical stimulation on Achilles tendon healing. Also mentioned is the interface tissue engineering for integrative soft-tissue healing to accelerate tendon-bone and ligament-bone healing.

The article discusses the impact of tissue engineering in clinical management of periodontal, maxillofacial and osseous defects in preparation for implant placement in the U.S. It notes the key elements involve in the manipulation of the tissue engineering. It also highlights the use of platelet-rich plasma as a source of growth factors in bone and periodontal regeneration.

Abstract: The purpose of this study was to evaluate soft tissue response to maxillo-mandibular counter-clockwise rotation, with TMJ reconstruction and mandibular advancement using TMJ Concepts® total joint prostheses, and maxillary osteotomies in 44 females. All patients were operated at Baylor University Medical Center, Dallas TX, USA, by one surgeon (Wolford). Eighteen patients had genioplasties with either porous block hydroxyapatite or hard tissue replacement implants (Group 2) 26 had no genioplasty (Group 1). Surgically, the maxilla moved forward and upward by counter-clockwise maxillo-mandibular rotation with greater horizontal movement in Group 2. Vertically, both groups showed diversity of maxillo-mandibular mean movement. Group 1 showed a consistent 1: 0.97 ratio of hard to soft tissue advancement at pogonion; Group 2 results were less consistent, with ratios between 1: 0.84 and 1: 1.02. Horizontal changes in upper lip morphology after maxillary advancement/impaction, VY closure, and alar base cinch sutures showed greater movement in both groups, than observed in hard tissue. Counter-clockwise rotation of the maxillo-mandibular complex using TMJ Concepts total joint prostheses resulted in similar soft tissue response as previously reported for traditional maxillo-mandibular advancement without counter-clockwise rotation of the occlusal plane. The association of chin implants, in the present sample, showed higher variability of soft tissue response. [Copyright &y& Elsevier]

Neurogenic bladder is a general term encompassing various neurologic dysfunctions in the bladder and external urethral sphincter caused by damage or disease. Therapeutic management options fall into the categories of conservative, minimally invasive or surgical. The current standard for surgical management is bladder augmentation using intestinal segments. However, because intestinal tissue possesses different functional characteristics to bladder tissue, numerous complications can ensue. Regenerative medicine uses combinations of cells and/or biomaterials to encourage regeneration of healthy tissue and offers an alternative approach for the replacement of lost or deficient organs, including the bladder. Promising results using the principles of regenerative medicine have already been obtained in children with neurogenic bladder caused by myelomeningocele. Human clinical trials, governed by the US FDA, are ongoing in the USA in both children and adults to further evaluate the safety and efficacy of this technology for regenerating bladders. More studies are in progress and additional advanced in this field can be anticipated. [ABSTRACT FROM AUTHOR]

Despite widespread hype and significant investment through the late 1980s and 1990s, cell-based therapeutics have largely failed from both a clinical and financial perspective. While the early pioneers were able to create clinically efficacious products, small margins coupled with small initial indications made it impossible to produce a reasonable return on the huge initial investments that had been made to support widespread research activities. Even as US FDA clearance opened up larger markets, investor interest waned, and the crown jewels of cell-based therapeutics went bankrupt or were rescued by corporate bailout. Despite the hard lessons learned from these pioneering companies, many of today's regenerative medicine companies are supporting nearly identical strategies. It remains to be seen whether or not our proposed tenets for investment and commercialization strategy yield an economic success or whether the original model can produce a return on investment sufficient to justify the large up-front investments. Irrespective of which approach yields a success, it is critically important that more of the second-generation products establish profitability if the field is to enjoy continued investment from both public and private sectors. [ABSTRACT FROM AUTHOR]

Background: This study evaluated the safety and effectiveness of a tissue-engineered skin product composed of viable neonatal keratinocytes and fibroblasts and compared it to a free gingival graft (FGG) in a procedure to enhance keratinized tissue (KT) and wound healing around teeth that do not require root coverage. Methods: Twenty five subjects were enrolled who had at least two non-adjacent teeth in contralateral quadrants exhibiting an insufficient zone of attached gingiva requiring soft tissue grafting where root coverage was not desired. One tooth was randomized to receive an FGG, and the other was randomized to receive bilayered cell therapy (BCT). The amount of KT was measured at baseline and 3 and 6 months, and the texture and color of the grafted tissue were compared to the surrounding tissue at months 1, 3, and 6. A questionnaire was used to determine subject preference at 6 months. Biopsies and persistence studies were performed on a subset of the subjects. Results: The FGG generated statistically significantly (P<0.001) more KT than the test device (BCT) (4.5 ± 0.80 mm versus 2.4 ± 1.02 mm); no significant difference in recession or clinical attachment level was detected between treatment groups (P = 0.212 and P = 0.448, respectively); and no significant differences were detected at any time point for bleeding on probing (BOP), resistance to muscle pull, or inflammation. The BCT group had significantly better color and texture match with surrounding tissue (P <0.001), and subject preference was significantly greater for the BCT group (P = 0.041). No device-related adverse events or safety issues occurred during the course of the study. Conclusions: The tissue engineered graft BCT was safe and capable of generating de novo KT without the morbidity and potential clinical difficulties associated with donor-site surgery. The amount of KT generated with FGG was greater than generated with BCT; however, 24 of 25 test sites demonstrated an increase in KT at 6 months, with more than three-quarters of the sites yielding ≥2 mm bands of KT. [ABSTRACT FROM AUTHOR]

There are >200,000 anterior cruciate ligament (ACL) ruptures each year in the United States, and, due to the poor healing properties of the ACL, surgical reconstruction with autograft or allograft tissue is the current treatment of these injuries. To regenerate the ACL, the ideal matrix should be biodegradable, porous, and exhibit sufficient mechanical strength to allow formation of neoligament tissue. Researchers have developed ACL scaffolds with collagen fibers, silk, biodegradable polymers, and composites with limited success. Our group has developed a biomimetic ligament replacement by using 3D braiding technology. In this preliminary in vivo rabbit model study for ACL reconstruction, the histological and mechanical evaluation demonstrated excellent healing and regeneration with our cell-seeded, tissue-engineered ligament replacement. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines the development of innovation in human tissue technologies as a form of regenerative medicine, firstly by applying ‘pollution ideas’ to contemporary trends in its risk regulation and to the processes of regulatory policy formation, and secondly by analysing the classificatory processes deployed in regulatory policy. The analysis draws upon data from fieldwork and documentary materials with a focus on the UK and EU (2002–05) and explores four arenas: governance and regulatory policy; commercialisation and the market; ‘evidentiality’ manifest in evidence-based policy; and publics’ and technology users’ values and ethics. The analysis suggests that there is a trend toward ‘purification’ across these arenas, both material and socio-political. A common process of partitioning is found in stakeholders’ attempts to define a clear terrain, which the field of tissue-engineered technology might occupy. We conclude that pollution ideas and partitioning processes are useful in understanding regulatory ordering and innovation in the emerging technological zone of human tissue engineering. [Copyright &y& Elsevier]

The emergence of tissue-engineered products (TEPs) raises a standard question for regulators: is the existing regulatory regime appropriate or is there a case for a new regulatory framework? In the USA, the FDA has developed a risk-based approach to TEPs, whereas in Europe, a common regulatory strategy for these products has not yet been implemented. In order to fill this perceived gap, member states have set up domestic rules, which has led to an unclear and patchy regulatory situation. The Regulation on Advanced Therapy Medicinal Products, voted on by the European Commission in November 2005, has been developed by European Union regulators to provide the necessary framework to regulate TEPs. As the text is still to be discussed and to be passed, many concerns have been raised regarding the appropriateness of the proposed framework. [ABSTRACT FROM AUTHOR]

Presents examples and insights from several educators' experiences teaching tissue engineering at the University of Kansas and the University of Michigan in Ann Arbor to serve as a guide both to those developing a new course in tissue engineering and those looking for ideas to supplement an existing tissue engineering course in the U.S. Selection of textbooks and reference reading materials for the course; Suggested topics to be covered in every tissue engineering course; Tips on making tissue engineering a quantitative course.

The article sheds light on various accomplishments and future perspectives in tissue engineering. A team of researchers in Switzerland, Germany and the U.S. have succeeded in engineering a living heart valve that resembles normal valves in both microstructure and mechanical properties. Engineering efficient structures is not and involves the contribution of researchers from other fields, such as material science and chemistry. A supporting matrix has to sustain and guide the growth of cells, and should provide all of the signals that are needed for cell growth, differentiation and cell interaction. Another important challenge for biologists is the selection of appropriate cells, and the conditions for their isolation, purification and cultivation.

Fulminant hepatic failure (FHF) attributes to rising medical cost and accounts for many deaths each year in the United States. Currently, the only solution is organ transplantation. Due to increasing donor organ shortage, many in need of transplantation continue to remain on the waiting list. Liver Assist Devices (LADs) are being used to temporarily sustain liver function and bridge the period between FHF and transplantation. Hepatic Tissue Engineering is a step toward alleviating the need for donor organs; yet many challenges must be overcome including scaffold choice, cell source and immunological barrierrs. Bioreactors have aided in hepatocyte survival and have proven to sustain viable cells for several weeks. Achieving the necessary functions required for hepatic replacement is aided by the incorporation of growth factors and mitogens many that now can be bound to the polymer scaffold and released in a timely manner. Utilizing concepts such as MicroElectroMechanical systems (MEMs) technology, our laboratory is able to mimic the natural vasculature of the liver and sustain functional and viable hepatocytes. Expanding and improving upon this platform technology, advancements made will continue toward the development of a fully functioning and implantable liver. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]