The safety of the cells used for Advanced Therapy Medicinal Products is crucial for patients. Reliable methods for the cell purification are very important for the commercialization of those new therapies. With the large production scale envisioned for commercialization, the cell isolation methods need to be efficient, robust, operationally simple and generic while ensuring cell biological functionality and safety. In this study, we used high magnetized magnetic agarose-based beads conjugated with protein A to develop a new method for cell separation. A high separation efficiency of 91% yield and consistent isolation performances were demonstrated using population mixtures of human mesenchymal stem cells and HER2+ SKBR3 cells (80:20, 70:30 and 30:70). Additionally, high robustness against mechanical stress and minimal unspecific binding obtained with the protein A base conjugated magnetic beads were significant advantages in comparison with the same magnetic microparticles where the antibodies were covalently conjugated. This study provided insights on features of large high magnetized microparticles, which is promising for the large-scale application of cell purification.
Heart regeneration is an unmet clinical need, hampered by limited renewal of adult cardiomyocytes and fibrotic scarring. Pluripotent stem cell-based strategies are emerging, but unravelling cellular dynamics of host–graft crosstalk remains elusive. Here, by combining lineage tracing and single-cell transcriptomics in injured non-human primate heart biomimics, we uncover the coordinated action modes of human progenitor-mediated muscle repair. Chemoattraction via CXCL12/CXCR4 directs cellular migration to injury sites. Activated fibroblast repulsion targets fibrosis by SLIT2/ROBO1 guidance in organizing cytoskeletal dynamics. Ultimately, differentiation and electromechanical integration lead to functional restoration of damaged heart muscle. In vivo transplantation into acutely and chronically injured porcine hearts illustrated CXCR4-dependent homing, de novo formation of heart muscle, scar-volume reduction and prevention of heart failure progression. Concurrent endothelial differentiation contributed to graft neovascularization. Our study demonstrates that inherent developmental programmes within cardiac progenitors are sequentially activated in disease, enabling the cells to sense and counteract acute and chronic injury.
Innovation is the process by which inventions or new ideas can generate economic and social value. Innovation in health sciences offers a vital route to developing novel approaches to unmet medical need and improving quality of life for patients. While the world-class UK science base has been instrumental in generating innovative ideas, the UK government has also played a pivotal strategic role. Through ensuring the appropriate environmental conditions to support the development and commercialisation of innovation, innovative technologies and therapies have been delivered. In addition, this has generated economic growth, increased productivity and promoted high-value employment. By creating a conducive policy environment using procurement intelligently and providing targeted direct support, government can also be highly effective at enticing the private sector to invest in innovation. Governments therefore, have a key role, as new fields develop, in breaking down barriers to enable industry and private investors to risk entering on a new path. The United Kingdom has many innovation assets particularly pertinent to cell and gene therapy; the challenge for successive UK governments over the last decade has been to ensure that there was an overarching vision and a coherent, strategic policy framework. This has enabled the effective support of the emergence and accelerated growth of this innovative industry. It is hoped that such science and technology promoting policies will deliver on the promise of cell and gene therapy to produce safe and effective new therapies with the potential to cure some diseases and disorders. This chapter aims to summarise the current UK innovation strategy.
Background:Despite recent advances in culture techniques for undifferentiated human Embryonic Stem Cells (hESCs), further improvements are required to facilitate research and translation of these cells in clinical settings. We have previously derived hESC lines that can be cultured in their undifferentiated state on regular plastic culture dishes, without the need for feeder cells or other coating supports, denoted Matrix-Free Growth hESCs (MFG-hESCs).Objective:In this study, we further characterize and compare MFG-hESCs to hESCs in order to understand the molecular differences responsible for the unique ability of MFG-hESCs.Results:Microarray analysis demonstrated that MFG-hESCs highly resemble feeder-cultured hESCs in global gene expression profile. Two identified groups of genes with differential expression were those encoding for ribosomal proteins and attachment proteins, such as the RGD (Arg-Gly-Asp)-associated proteins. Real-time PCR and flow cytometry corroborated the microarray results. Culture of MFG-hESCs in the presence of RGD peptides resulted in decreased attachment ability compared to cells cultured in the presence of RGES (Arg-Gly-Asp-Ser) peptides.Conclusion:This study demonstrates that MFG-hESC lines overexpress cell attachment proteins but retain the typical characteristics of undifferentiated feeder-cultured hESCs. The ability to culture high-quality pluripotent stem cells in feeder- and matrix-free conditions creates a new opportunities for their large-scale manufacturing for experimental research and translational applications.
Stem cells can be isolated from a variety of sources and they are typically classified based on their tissue of origin. Embryonic stem cells are, as the name indicates, derived from the inner cell mass of pre-implantation stage blastocysts at day 5-7 post fertilization. These cells possess qualities such as pluripotency and a seemingly limitless capacity to proliferate in vitro in their undifferentiated state. Embryonic stem cells were first derived from mouse embryos in the early 1980s but have now been derived from a number of different species including rat, rabbit, sheep, and human. This chapter focuses on human embryonic stem cells and describes techniques used for their derivation and culture. In addition, the basic properties of these cells are illustrated, including some examples of their capacity to differentiate to various precursors and functional cell types. Finally, some areas of applications for these cells are discussed with emphasis on their possible future use in regenerative medicine.
This paper summarizes the proceedings of a workshop held at Trinity Hall, Cambridge to discuss comparability and includes additional information and references to related information added subsequently to the workshop. Comparability is the need to demonstrate equivalence of product after a process change; a recent publication states that this 'may be difficult for cell-based medicinal products'. Therefore a well-managed change process is required which needs access to good science and regulatory advice and developers are encouraged to seek help early. The workshop shared current thinking and best practice and allowed the definition of key research questions. The intent of this report is to summarize the key issues and the consensus reached on each of these by the expert delegates.
The development of induced pluripotent stem cells offers the possibility of the scalable manufacture of cellular therapies for regenerative medicine. Moreover, donors can be selected on the basis of major transplant antigen systems to match the widest possible number of recipients worldwide, reducing the likely risk of immunological rejection and the degree of immune suppression or tolerance required. If such cell lines are to be broadly available, there will need to be mutual recognition of common standards across different jurisdictions. Extensive international collaboration will be required around issues such as determination of the optimal homozygous human leukocyte antigens (HLA) panel, donor selection, screening and consent, good manufacturing practice (GMP), standards and quality control and regulatory legislation. The challenges in establishing a global GMP induced pluripotent stem cell (iPSC) haplobank are formidable. We argue that now is the time to attempt to reach international agreement around common standards for GMP iPSC manufacture before the field develops in a fragmented manner.
The nature of cellular structure was first recognized by the British scientist Robert Hooke and described in Micrographia (Royal Society, September 1665) although their physiological role was not recognized for almost 200 years (Matthias Jakob Schleiden 1838 and Theodor Schwann 1839 working on
Cell therapies offer the promise of treating and altering the course of diseases which cannot be addressed adequately by existing pharmaceuticals. Cell therapies are a diverse group across cell types and therapeutic indications and have been an active area of research for many years but are now strongly emerging through translation and towards successful commercial development and patient access. In this article, we present a description of a classification of cell therapies on the basis of their underlying technologies rather than the more commonly used classification by cell type because the regulatory path and manufacturing solutions are often similar within a technology area due to the nature of the methods used. We analyse the progress of new cell therapies towards clinical translation, examine how they are addressing the clinical, regulatory, manufacturing and reimbursement requirements, describe some of the remaining challenges and provide perspectives on how the field may progress for the future.
Cell Therapy Clinical Trial and Preclinical Research databases have been established by the Cell Therapy Catapult to document current and future cell therapy clinical trials in the UK. We identified 41 ongoing trials in April 2014, an increase of seven trials from April 2013. In addition, we identified 45 late-stage preclinical research projects. The majority of the clinical trials are early phase, primarily led by academic groups. The leading therapeutic areas are cancer, cardiology and neurology. The trends in the UK are also seen globally. As the field matures, more later phase and commercial studies will emerge and the challenges will likely evolve into how to manufacture sufficient cell quantities, manage complex logistics for multi-center trials and control cost.
Human induced pluripotent stem cells (iPSCs) are potential cell sources for regenerative medicine; however, clinical applications of iPSCs are restricted because of undesired genomic modifications associated with most reprogramming protocols. We show, for the first time, that chondrocytes from autologous chondrocyte implantation (ACI) donors can be efficiently reprogrammed into iPSCs using a nonintegrating method based on mRNA delivery, resulting in footprint-free iPSCs (no genome-sequence modifications), devoid of viral factors or remaining reprogramming molecules. The search for universal allogeneic cell sources for the ACI regenerative treatment has been difficult because making chondrocytes with high matrix-forming capacity from pluripotent human embryonic stem cells has proven challenging and human mesenchymal stem cells have a predisposition to form hypertrophic cartilage and bone. We show that chondrocyte-derived iPSCs can be redifferentiated in vitro into cartilage matrix-producing cells better than fibroblast-derived iPSCs and on par with the donor chondrocytes, suggesting the existence of a differentiation bias toward the somatic cell origin and making chondrocyte-derived iPSCs a promising candidate universal cell source for ACI. Whole-genome single nucleotide polymorphism array and karyotyping were used to verify the genomic integrity and stability of the established iPSC lines. Our results suggest that RNA-based technology eliminates the risk of genomic integrations or aberrations, an important step toward a clinical-grade cell source for regenerative medicine such as treatment of cartilage defects and osteoarthritis.
To overcome the limitations and misjudgments of conventional prediction of arrhythmic cardiotoxicity, we have developed an on-chip in vitro predictive cardiotoxicity assay using cardiomyocytes derived from human stem cells employing a constructive spatiotemporal two step measurement of fluctuation (short-term variability; STV) of cell's repolarization and cell-to-cell conduction time, representing two origins of lethal arrhythmia. Temporal STV of field potential duration (FPD) showed a potential to predict the risks of lethal arrhythmia originated from repolarization dispersion for false negative compounds, which was not correctly predicted by conventional measurements using animal cells, even for non-QT prolonging clinical positive compounds. Spatial STV of conduction time delay also unveiled the proarrhythmic risk of asynchronous propagation in cell networks, whose risk cannot be correctly predicted by single-cell-based measurements, indicating the importance of the spatiotemporal fluctuation viewpoint of in vitro cell networks for precise prediction of lethal arrhythmia reaching clinical assessment such as thorough QT assay.
Mesenchymal stroma cells (MSCs) have a high potential for novel cell therapy approaches in clinical transplantation. Commonly used bone marrow-derived MSCs (BM-MSCs), however, have a restricted proliferative capacity and cultures are difficult to standardize. Recently developed human embryonic stem cell-derived mesenchymal stroma cells (hES-MSCs) might represent an alternative and unlimited source of hMSCs. We therefore compared human ES-cell-derived MSCs (hES-MP002.5 cells) to normal human bone marrow-derived MSCs (BM-MSCs). hES-MP002.5 cells had lower yet reasonable CFU-F capacity compared with BM-MSC (8±3 versus 29±13 CFU-F per 100 cells). Both cell types showed similar immunophenotypic properties, i.e. cells were positive for CD105, CD73, CD166, HLA-ABC, CD44, CD146, CD90, and negative for CD45, CD34, CD14, CD31, CD117, CD19, CD 271, SSEA-4 and HLA-DR. hES-MP002.5 cells, like BM-MSCs, could be differentiated into adipocytes, osteoblasts and chondrocytes in vitro. Neither hES-MP002.5 cells nor BM-MSCs homed to the bone marrow of immune-deficient NSG mice following intravenous transplantation, whereas intra-femoral transplantation into NSG mice resulted in engraftment for both cell types. In vitro long-term culture-initiating cell assays and in vivo co-transplantation experiments with cord blood CD34+ hematopoietic cells demonstrated furthermore that hES-MP002.5 cells, like BM-MSCs, possess potent stroma support function. In contrast to BM-MSCs, however, hES-MP002.5 cells showed no or only little activity in mixed lymphocyte cultures and phytohemagglutinin (PHA) lymphocyte stimulation assays. In summary, ES-cell derived MSCs might be an attractive unlimited source for stroma transplantation approaches without suppressing immune function.
Human pluripotent stem cells provide unique possibilities for in vitro studies of human cells in basic research, disease modeling as well as in industrial applications. By introducing relevant genome engineering technology, and thereby creating, for example, reporter cell lines, one will facilitate and improve safety pharmacology, toxicity testing, and can help the scientists to better understand pathological processes in humans. This review discusses how the merger of these two fields, human pluripotent stem cells and genome engineering, form extremely powerful tools and how they have been implemented already within the scientific community. In sharp contrast to immortalized human cell lines, which are both easy to expand and very simple to transfect, the genetically modified pluripotent stem cell line can be directed to a specific cell lineage and provide the user with highly relevant information. We highlight some of the challenges the field had to solve and how new technology advancements has removed the early bottlenecks.
Bone tissue engineering represents a promising strategy to obviate bone deficiencies, allowing the ex vivo construction of bone substitutes with unprecedented potential in the clinical practice. Considering that in the human body cells are constantly stimulated by chemical and mechanical stimuli, the use of bioreactor is emerging as an essential factor for providing the proper environment for the reproducible and large-scale production of the engineered substitutes. Human mesenchymal stem cells (hMSCs) are experimentally relevant cells but, regardless the encouraging results reported after culture under dynamic conditions in bioreactors, show important limitations for tissue engineering applications, especially considering their limited proliferative potential, loss of functionality following protracted expansion, and decline in cellular fitness associated with aging. On the other hand, we previously demonstrated that human embryonic stem cell-derived mesodermal progenitors (hES-MPs) hold great potential to provide a homogenous and unlimited source of cells for bone engineering applications. Based on prior scientific evidence using different types of stem cells, in the present study we hypothesized that dynamic culture of hES-MPs in a packed bed/column bioreactor had the potential to affect proliferation, expression of genes involved in osteogenic differentiation, and matrix mineralization, therefore resulting in increased bone-like tissue formation. The reported findings suggest that hES-MPs constitute a suitable alternative cell source to hMSCs and hold great potential for the construction of bone substitutes for tissue engineering applications in clinical settings.
PURPOSE:The aim of this study was to investigate whether cells originating from human embryonic stem cells (hESCs) could be successfully transplanted onto a partially wounded human cornea. A second aim was to study the ability of the transplanted cells to differentiate into corneal epithelial-like cells.METHODS:Spontaneously, differentiated hESCs were transplanted onto a human corneal button (without limbus) with the epithelial layer partially removed. The cells were cultured on Bowman's membrane for up to 9 days, and the culture dynamics documented in a time-lapse system. As the transplanted cells originated from a genetically engineered hESC line, they all expressed green fluorescent protein, which facilitated their identification during the culture experiments, tissue preparation and analysis. To detect any differentiation into human corneal epithelial-like cells, we analysed the transplanted cells by immunohistochemistry using antibodies specific for CK3, CK15 and PAX6.RESULTS:The transplanted cells established and expanded on Bowman's membrane, forming a 1-4 cell layer surrounded by host corneal epithelial cells. Expression of the corneal marker PAX6 appeared 3 days after transplantation, and after 6 days, the cells were expressing both PAX6 and CK3.CONCLUSION:This shows that it is possible to transplant cells originating from hESCs onto Bowman's membrane with the epithelial layer partially removed and to get these cells to establish, grow and differentiate into corneal epithelial-like cells in vitro.
This chapter describes the principles for derivation and maintenance of human embryonic stem cells. Detailed protocols are outlined and researchers who are generally skilled in mammalian cell culture should be able to repeat the processes successfully. Further, the protocols are intended for scientists who do not have access to advanced IVF equipment and therefore cannot perform, e.g. assisted hatching. In addition to derivation, we also discuss characterisation and banking of hES cells.
For more than a decade, human mesenchymal stem cells (hMSCs) have been used in bone tissue-engineering research. More recently some of the focus in this field has shifted towards the use of embryonic stem cells. While it is well known that hMSCs are able to form bone when implanted subcutaneously in immune-deficient mice, the osteogenic potential of embryonic stem cells has been mainly assessed in vitro. Therefore, we performed a series of studies to compare the in vitro and in vivo osteogenic capacities of human and mouse embryonic stem cells to those of hMSCs. Embryonic and mesenchymal stem cells showed all characteristic signs of osteogenic differentiation in vitro when cultured in osteogenic medium, including the deposition of a mineralized matrix and expression of genes involved in osteogenic differentiation. As such, based on the in vitro results, osteogenic ES cells could not be discriminated from osteogenic hMSCs. Nevertheless, although osteogenic hMSCs formed bone upon implantation, osteogenic cells derived from both human and mouse embryonic stem cells did not form functional bone, indicated by absence of osteocytes, bone marrow and lamellar bone. Although embryonic stem cells show all signs of osteogenic differentiation in vitro, it appears that, in contrast to mesenchymal stem cells, they do not possess the ability to form bone in vivo when a similar culture method and osteogenic differentiation protocol was applied.
This chapter contains sections titled: Introduction Background Applications Perspectives References