Decellularized matrices for tumor cell modeling.

Collagen is the main component of the extracellular matrix and it plays a key role in tumor progression. Commercial collagen solutions are derived from animals, such as rat-tail and bovine or porcine skin. Their cost is quite high and the product is stable only at low temperature, with the disadvantage of a short expiring date. Most importantly, lot-to-lot variability can occur and the reconstituted collagen gels differ significantly from native tissues in terms of both structure and stiffness. In this chapter, we describe a straightforward method to use native, collagen rich skin samples derived from by-products of the tanning industry. The protocol proposed preserves the microstructure of the ovine skin collagen network, offering structurally competent and more relevant model to investigate cell behavior in vitro. Other advantages of the proposed procedure consist in the cost-effectiveness of the process and an increased level of reproducibility. The decellularized ovine skin samples support the adhesion and growth of different cancer cell lines (pancreatic, breast and melanoma cells). The proposed decellularized skin scaffolds are meant as future low-cost competitors for conventional porous scaffold derived by biomaterials, since they offer a biomimetic environment for the cells.

Early cost-utility analysis of tissue-engineered heart valves compared to bioprostheses in the aortic position in elderly patients.

OBJECTIVES: Aortic valve disease is the most frequent indication for heart valve replacement with the highest prevalence in elderly. Tissue-engineered heart valves (TEHV) are foreseen to have important advantages over currently used bioprosthetic heart valve substitutes, most importantly reducing valve degeneration with subsequent reduction of re-intervention. We performed early Health Technology Assessment of hypothetical TEHV in elderly patients (≥ 70 years) requiring surgical (SAVR) or transcatheter aortic valve implantation (TAVI) to assess the potential of TEHV and to inform future development decisions. METHODS: Using a patient-level simulation model, the potential cost-effectiveness of TEHV compared with bioprostheses was predicted from a societal perspective. Anticipated, but currently hypothetical improvements in performance of TEHV, divided in durability, thrombogenicity, and infection resistance, were explored in scenario analyses to estimate quality-adjusted life-year (QALY) gain, cost reduction, headroom, and budget impact. RESULTS: Durability of TEHV had the highest impact on QALY gain and costs, followed by infection resistance. Improved TEHV performance (- 50% prosthetic valve-related events) resulted in lifetime QALY gains of 0.131 and 0.043, lifetime cost reductions of €639 and €368, translating to headrooms of €3255 and €2498 per hypothetical TEHV compared to SAVR and TAVI, respectively. National savings in the first decade after implementation varied between €2.8 and €11.2 million (SAVR) and €3.2-€12.8 million (TAVI) for TEHV substitution rates of 25-100%. CONCLUSIONS: Despite the relatively short life expectancy of elderly patients undergoing SAVR/TAVI, hypothetical TEHV are predicted to be cost-effective compared to bioprostheses, commercially viable and result in national cost savings when biomedical engineers succeed in realising improved durability and/or infection resistance of TEHV.

Extruded Bioreactor Perfusion Culture Supports the Chondrogenic Differentiation of Human Mesenchymal Stem/Stromal Cells in 3D Porous Poly(ɛ-Caprolactone) Scaffolds.

Novel bioengineering strategies for the ex vivo fabrication of native-like tissue-engineered cartilage are crucial for the translation of these approaches to clinically manage highly prevalent and debilitating joint diseases. Bioreactors that provide different biophysical stimuli have been used in tissue engineering approaches aimed at enhancing the quality of the cartilage tissue generated. However, such systems are often highly complex, expensive, and not very versatile. In the current study, a novel, cost-effective, and customizable perfusion bioreactor totally fabricated by additive manufacturing (AM) is proposed for the study of the effect of fluid flow on the chondrogenic differentiation of human bone-marrow mesenchymal stem/stromal cells (hBMSCs) in 3D porous poly(ɛ-caprolactone) (PCL) scaffolds. hBMSCs are first seeded and grown on PCL scaffolds and hBMSC-PCL constructs are then transferred to 3D-extruded bioreactors for continuous perfusion culture under chondrogenic inductive conditions. Perfused constructs show similar cell metabolic activity and significantly higher sulfated glycosaminoglycan production (≈1.8-fold) in comparison to their non-perfused counterparts. Importantly, perfusion bioreactor culture significantly promoted the expression of chondrogenic marker genes while downregulating hypertrophy. This work highlights the potential of customizable AM platforms for the development of novel personalized repair strategies and more reliable in vitro models with a wide range of applications.

Scalable and cost-effective generation of osteogenic micro-tissues through the incorporation of inorganic microparticles within mesenchymal stem cell spheroids.

Mesenchymal stem cells (MSCs) are considered primary candidates for treating complex bone defects in cell-based therapy and tissue engineering. Compared with monolayer cultures, spheroid cultures of MSCs (mesenspheres) are favorable due to their increased potential for differentiation, extracellular matrix (ECM) synthesis, paracrine activity, and in vivo engraftment. Here, we present a strategy for the incorporation of microparticles for the fabrication of osteogenic micro-tissues from mesenspheres in a cost-effective and scalable manner. A facile method was developed to synthesize mineral microparticles with cell-sized spherical shape, biphasic calcium phosphate composition (hydroxyapatite and ß-tricalcium phosphate), and a microporous structure. Calcium phosphate microparticles (CMPs) were incorporated within the mesenspheres through mixing with the single cells during cell aggregation. Interestingly, the osteogenic genes were upregulated significantly (collagen type 1 (Col 1) 30-fold, osteopontin (OPN) 10-fold, and osteocalcin (OCN) 3-fold) after 14 days of culture with the incorporated CMPs, while no significant upregulation was observed with the incorporation of gelatin microparticles. The porous structure of the CMPs was exploited for loading and sustained release of an angiogenic small molecule. Dimethyloxaloylglycine (DMOG) was loaded efficiently onto the CMPs (loading efficiency: 65.32 ± 6%) and showed a sustained release profile over 12 days. Upon incorporation of the DMOG-loaded CMPs (DCMPs) within the mesenspheres, a similar osteogenic differentiation and an upregulation in angiogenic genes (VEGF 5-fold and kinase insert domain (KDR) 2-fold) were observed after 14 days of culture. These trends were also observed in immunostaining analysis. To evaluate scalable production of the osteogenic micro-tissues, the incorporation of microparticles was performed during cell aggregation in a spinner flask. The DCMPs were efficiently incorporated and directed the mesenspheres toward osteogenesis and angiogenesis. Finally, the DCMP mesenspheres were loaded within a three-dimensional printed cell trapper and transplanted into a critical-sized defect in a rat model. Computed tomography and histological analysis showed significant bone formation with blood vessel reconstruction after 8 weeks in this group. Taken together, we provide a scalable and cost-effective approach for fabrication of osteogenic micro-tissues, as building blocks of macro-tissues, that can address the large amounts of cells required for cell-based therapies.

What Is the Potential of Tissue-Engineered Pulmonary Valves in Children?

BACKGROUND: As a living heart valve substitute with growth potential and improved durability, tissue-engineered heart valves (TEHVs) may prevent reinterventions that are currently often needed in children with congenital heart disease. We performed early health technology assessment to assess the potential cost-effectiveness of TEHVs in children requiring right ventricular outflow tract reconstruction (RVOTR). METHODS: A systematic review and meta-analysis was conducted of studies reporting clinical outcome after RVOTR with existing heart valve substitutes in children (mean age ≤12 years or maximum age ≤21 years) published between January 1, 2000, and May 2, 2018. Using a patient-level simulation model, costs and effects of RVOTR with TEHVs compared with existing heart valve substitutes were assessed from a health care perspective applying a 10-year time horizon. Improvements in performance of TEHVs, divided in durability, thrombogenicity, and infection resistance, were explored to estimate quality-adjusted life year (QALY) gain, cost reduction, headroom, and budget impact associated with TEHVs. RESULTS: Five-year freedom from reintervention after RVOTR with existing heart valve substitutes was 46.1% in patients less than or equal to 2 years of age and 81.1% in patients greater than 2 years of age. Improvements in durability had the highest impact on QALYs and costs. In the improved TEHV performance scenario (durability ≥5 years and -50% other valve-related events), QALY gain was 0.074 and cost reduction was €10,378 per patient, translating to maximum additional costs of €11,856 per TEHV compared with existing heart valve substitutes. CONCLUSIONS: This study showed that there is room for improvement in clinical outcomes in children requiring RVOTR. If TEHVs result in improved clinical outcomes, they are expected to be cost-effective compared with existing heart valve substitutes.

An Overview of the Tissue Engineering Market in the United States from 2011 to 2018.

IMPACT STATEMENT: This report seeks to provide an update of the current landscape of the tissue engineering market in the United States from an unbiased point of view by analyzing the financial reports provided by tissue engineering companies, as well as data from publicly available clinical trials with relevant tissue engineering applications.

Integrated generation of induced pluripotent stem cells in a low-cost device.

Human induced pluripotent stem cells (iPSCs) have unlimited proliferation capability and potential to differentiate into all somatic cells. Their derivatives contain patients' genetic information and can model many diseases. Additionally, derivatives of patient-specific iPSCs induce minimal immune rejection in vivo. With this unique combination of properties, iPSCs open the avenue to personalized medicine including personalized drug screening, toxicity test, cell therapy and tissue engineering. However, the further advance of iPSC-based personalized medicine is currently limited by the difficulty to generate iPSCs for large populations and at affordable cost. We here report a low-cost device to address this challenge. The device allows the entire bioprocess for generating high quality and quantity of iPSCs for one patient to be done automatically within a closed conical tube without cell passaging. Additionally, iPSCs can be further differentiated into somatic cells in the device. Thus, the device also allows integrated iPSCs generation, expansion and differentiation to produce any somatic cell types. This device can be made in large quantities at low cost for manufacturing iPSCs (and their derivatives in necessary) for large populations at affordable cost. It will significantly advance the iPSCs-based personalized medicine.

Regenerative Medicine Venturing at the University-Industry Boundary: Implications for Institutions, Entrepreneurs, and Industry.

Regenerative medicine research at university laboratories has outpaced commercial activity. Legal, regulatory, funding, technological, and operational uncertainty have slowed market entry of regenerative medicine treatments. As a result, commercial development has often been led by entrepreneurial ventures rather than large biopharma firms. Translating regenerative medicine across the university-industry boundary links academic scientists, technology transfer organizations, funders, and entrepreneurs. Conflicting motivations among the participants may significantly hinder these efforts. Unproven downstream business models for regenerative medicine delivery further complicate the entrepreneurial process. This chapter explores the challenges associated with entrepreneurial activity commercializing regenerative medicine science developed at research institutions.

A Customizable, Low-Cost Perfusion System for Sustaining Tissue Constructs.

The fabrication of engineered vascularized tissues and organs requiring sustained, controlled perfusion has been facilitated by the development of several pump systems. Currently, researchers in the field of tissue engineering require the use of pump systems that are in general large, expensive, and generically designed. Overall, these pumps often fail to meet the unique demands of perfusing clinically useful tissue constructs. Here, we describe a pumping platform that overcomes these limitations and enables scalable perfusion of large, three-dimensional hydrogels. We demonstrate the ability to perfuse multiple separate channels inside hydrogel slabs using a preprogrammed schedule that dictates pumping speed and time. The use of this pump system to perfuse channels in large-scale engineered tissue scaffolds sustained cell viability over several weeks.

Controlling the extrudate swell in melt extrusion additive manufacturing of 3D scaffolds: a designed experiment.

Tissue engineering using three-dimensional porous scaffolds has shown promise for the restoration of normal function in injured and diseased tissues and organs. Rigorous control over scaffold architecture in melt extrusion additive manufacturing is highly restricted mainly due to pronounced variations in the deposited strand diameter upon any variations in process conditions and polymer viscoelasticity. We have designed an I-optimal, split-plot experiment to study the extrudate swell in melt extrusion additive manufacturing and to control the scaffold architecture. The designed experiment was used to generate data to relate three responses (swell, density, and modulus) to a set of controllable factors (plotting needle diameter, temperature, pressure, and the dispensing speed). The fitted regression relationships were used to optimize the three responses simultaneously. The swell response was constrained to be close to 1 while maximizing the modulus and minimizing the density. Constraining the extrudate swell to 1 generates design-driven scaffolds, with strand diameters equal to the plotting needle diameter, and allows a greater control over scaffold pore size. Hence, the modulus of the scaffolds can be fully controlled by adjusting the in-plane distance between the deposited strands. To the extent of the model's validity, we can eliminate the effect of extrudate swell in designing these scaffolds, while targeting a range of porosity and modulus appropriate for bone tissue engineering. The result of this optimization was a predicted modulus of 14 MPa and a predicted density of 0.29 g/cm3 (porosity ≈ 75%) using polycaprolactone as scaffold material. These predicted responses corresponded to factor levels of 0.6 µm for the plotting needle diameter, plotting pressure of 2.5 bar, melt temperature of 113.5 °C, and dispensing speed of 2 mm/s. The validation scaffold enabled us to quantify the percentage difference for the predictions, which was 9.5% for the extrudate swell, 19% for the density, and 29% for the modulus.

A Cost-Effective Culture System for the In Vitro Assembly, Maturation, and Stimulation of Advanced Multilayered Multiculture Tubular Tissue Models.

The development of tubular engineered tissues is a challenging research area aiming to provide tissue substitutes but also in vitro models to test drugs, medical devices, and even to study physiological and pathological processes. In this work, the design, fabrication, and validation of an original cost-effective tubular multilayered-tissue culture system (TMCS) are reported. By exploiting cellularized collagen gel as scaffold, a simple moulding technique and an endothelialization step on a rotating system, TMCS allowed to easily prepare in 48 h, trilayered arterial wall models with finely organized cellular composition and to mature them for 2 weeks without any need of manipulation. Multilayered constructs incorporating different combinations of vascular cells are compared in terms of cell organization and viscoelastic mechanical properties demonstrating that cells always progressively aligned parallel to the longitudinal direction. Also, fibroblast compacted less the collagen matrix and appeared crucial in term of maturation/deposition of elastic extracellular matrix. Preliminary studies under shear stress stimulation upon connection with a flow bioreactor are successfully conducted without damaging the endothelial monolayer. Altogether, the TMCS herein developed, thanks to its versatility and multiple functionalities, holds great promise for vascular tissue engineering applications, but also for other tubular tissues such as trachea or oesophagus.

Stem cell roadmap - The industrial point of view.

CELLforCURE is a French Contract Development and Manufacturing Organization (CDMO) dedicated to industrialization and process development for routine manufacturing, GMP manufacturing for clinical and commercial batches and regulatory services and associated logistics. CELLforCURE is a subsidiary of LFB Group.Stem cells fields of application gather cell and gene therapy as well as tissue engineering. According to VisionGain survey, cell therapy medicinal products will remain predominant in the future.Clinical trials are sponsored either by universities or private companies. Most of clinical trials are performed in oncology (53%). More than 100 clinical trials are currently performed in France, involving 36 products in clinical phases II or II/III.Tomorrow's regenerative medicine will be organ reconstruction using scaffolds and bioprinting technologies. The expected applications in the near future could be skin, cornea, blood vessels, retina, urethra and trachea. There are still important issues to overcome: create the vasculature and neuron connection.Solutions are expected regarding I) fundamental biology, in particular better understanding of IPS behavior and metabolism, precursor differentiation conditions, sustainability of induced genetic changes, II) technical approaches which involves injectable preservation medium, high density cells and centrifugation system.

Overcoming Challenges Facing Advanced Therapies in the EU Market.

While advanced therapy medicinal products offer great clinical promise, most EU-approved products have not achieved satisfactory commercial performance. Here we highlight a number of issues that prevent current products from obtaining commercial success and pitfalls that developers must overcome in future product development.

Accessible bioprinting: adaptation of a low-cost 3D-printer for precise cell placement and stem cell differentiation.

The precision and repeatability offered by computer-aided design and computer-numerically controlled techniques in biofabrication processes is quickly becoming an industry standard. However, many hurdles still exist before these techniques can be used in research laboratories for cellular and molecular biology applications. Extrusion-based bioprinting systems have been characterized by high development costs, injector clogging, difficulty achieving small cell number deposits, decreased cell viability, and altered cell function post-printing. To circumvent the high-price barrier to entry of conventional bioprinters, we designed and 3D printed components for the adaptation of an inexpensive 'off-the-shelf' commercially available 3D printer. We also demonstrate via goal based computer simulations that the needle geometries of conventional commercially standardized, 'luer-lock' syringe-needle systems cause many of the issues plaguing conventional bioprinters. To address these performance limitations we optimized flow within several microneedle geometries, which revealed a short tapered injector design with minimal cylindrical needle length was ideal to minimize cell strain and accretion. We then experimentally quantified these geometries using pulled glass microcapillary pipettes and our modified, low-cost 3D printer. This systems performance validated our models exhibiting: reduced clogging, single cell print resolution, and maintenance of cell viability without the use of a sacrificial vehicle. Using this system we show the successful printing of human induced pluripotent stem cells (hiPSCs) into Geltrex and note their retention of a pluripotent state 7 d post printing. We also show embryoid body differentiation of hiPSC by injection into differentiation conducive environments, wherein we observed continuous growth, emergence of various evaginations, and post-printing gene expression indicative of the presence of all three germ layers. These data demonstrate an accessible open-source 3D bioprinter capable of serving the needs of any laboratory interested in 3D cellular interactions and tissue engineering.

Benevolent technotopias and hitherto unimaginable meats: Tracing the promises of in vitro meat.

Today, in vitro (Latin: in glass) meat researchers strive to overhaul meat production technologies by producing meat outside animal bodies, primarily by culturing cells. In the process, meat should become healthier, more environmentally friendly and kinder to animals. In this article, I scrutinize (and problematize) this promissory discourse by examining the world that proponents envision alongside the world from which promises emerge. First, I trace the increasing number of publications striving to pinpoint the nature of in vitro meat to unveil the creation of an in vitro meat canon wherein perceived possibilities become taken for granted. Second, I investigate how the promissory discourse is often relatively silent on key aspects of how this technology could remake the world. Wet laboratories, animals and end products become foregrounded at the expense of political economy and the biophysical properties of cultured cells. Thus, questions concerning how funding requirements shape representations of this new technology, together with in vitro meat's particular socio-spatial and socio-ecological implications, become problematically de-emphasized.

Cost of Stem Cell-Based Tissue-Engineered Airway Transplants in the United Kingdom: Case Series.

Stem cell-based tissue-engineered tracheas are at an early stage in their product development cycle. Tens of patients have been treated worldwide in predominantly compassionate use settings, demonstrating significant promise. This potentially life-saving treatment is complex, and the cost and its implications for such treatments are yet to be fully understood. The costs are compounded by varying strategies for graft preparation and transplant, resulting in differing clinical and laboratory costs from different research groups. In this study, we present a detailed breakdown of the clinical and manufacturing costs for three of the United Kingdom (UK) patients treated with such transplants. All three patients were treated under Compassionate Use legislation, within the UK National Health Service (NHS) hospital setting. The total costs for the three UK patients treated ranged from $174,420 to $740,500. All three patients were in a state of poor health at time of treatment and had a number of complexities in addition to the restricted airway. This is the first time a cost analysis has been made for a tissue-engineered organ and provides a benchmark for future studies, as well as comparative data for use in reimbursement considerations.