hESCCO: development of good practice models for hES cell derivation

Species Choice and Model Use: Reviving Research on Human Development

While model organisms have had many historians, this article places studies of humans, and particularly our development, in the politics of species choice. Human embryos, investigated directly rather than via animal surrogates, have gone through cycles of attention and neglect. In the past 60 years they moved from the sidelines to center stage. Research was resuscitated in anatomy, launched in reproductive biomedicine, molecular genetics, and stem-cell science, and made attractive in developmental biology. I explain this surge of interest in terms of rivalry with models and reliance on them. The greater involvement of medicine in human reproduction, especially through in vitro fertilization, gave access to fresh sources of material that fed critiques of extrapolation from mice and met demands for clinical relevance or "translation." Yet much of the revival depended on models. Supply infrastructures and digital standards, including biobanks and virtual atlases, emulated community resources for model organisms. Novel culture, imaging, molecular, and postgenomic methods were perfected on less precious samples. Toing and froing from the mouse affirmed the necessity of the exemplary mammal and its insufficiency justified inquiries into humans. Another kind of model-organoids and embryo-like structures derived from stem cells-enabled experiments that encouraged the organization of a new field, human developmental biology. Research on humans has competed with and counted on models.

Acquisition and Reception of Primary Tissues, Cells, or Other Biological Specimens

The use and banking of biological material for research or clinical application is a well-established practice. The material can be of human or non-human origin. The processes involved in this type of activity, from the sourcing to receipt of materials, require adherence to a set of best practice principles that assure the ethical and legal procurement, traceability, and quality of materials.

MicroRNAs in spent blastocyst culture medium are derived from trophectoderm cells and can be explored for human embryo reproductive competence assessment

OBJECTIVE

To assess whether extracellular microRNAs (miRNAs) can be accurately profiled from spent blastocyst culture media (SBM) and used as embryonic biomarkers.

DESIGN

Prospective cohort study.

SETTING

Private and academic in vitro fertilization centers.

PATIENT(S)

Inner cell mass-free trophectoderm (TE) samples and their relative SBM from five good-quality human blastocysts.

INTERVENTION(S)

Protocol for miRNA purification and analysis based on quantitative polymerase chain reaction set and validated on human embryonic stem cells (hESCs) and on SBM with and without biological variability.

MAIN OUTCOMES MEASURE(S)

Analysis of miRNAs in culture media in relation with TE cells and comparison of miRNA profiles between implanted and unimplanted euploid blastocysts.

RESULT(S)

Culture media from embryos in the cleavage, morula, and blastocyst stages were collected to investigate the presence of miRNAs. The SBM were prospectively collected from euploid implanted (n = 25) and unimplanted blastocysts (n = 28) for comparison. We hypothesized that human embryos secrete miRNAs in culture media that can be used as biomarkers. The comparative analysis of TE and SBM samples revealed that 96.6% (57 of 59; 95 CI, 88.3-99.6) of the miRNAs detected in the SBM were expressed from TE cells, suggesting a TE origin. The culture media collected from cleavage and morula stage embryos showed a pattern similar to blanks, suggesting that miRNAs profiling from spent culture media applies only for blastocysts. MicroRNAs analysis of SBM from euploid implanted and unimplanted blastocysts highlighted two miRNAs (miR-20a, miR-30c) that showed increased concentrations in the former and were predicted in silico to be involved in 23 implantation-related pathways.

CONCLUSION(S)

MicroRNAs secreted from human blastocysts in culture media can be profiled with high reproducibility, and this approach can be further explored for noninvasive embryo selection.

Perception and knowledge about stem cell and tissue engineering research: a survey amongst researchers and medical practitioners in perinatology

INTRODUCTION

Stem cell and tissue engineering (SC&TE) research remain controversial. Polemics are potential hurdles for raising public funds for research and clinical implementation. In view of future applications of SC&TE in perinatal conditions, we aimed to measure the background knowledge, perceptions or beliefs on SC&TE research among clinicians and academic researchers with perinatal applications on the department's research agenda.

MATERIAL AND METHODS

We polled three professional categories: general obstetrician gynecologists, perinatologists and basic or translational researchers in development and regeneration. The survey included questions on demographics, work environment, educational background, general knowledge, expectations, opinions and ethical reflections of the respondent about SC&TE.

RESULTS

The response rate was 39 %. Respondents were mainly female (54 %) and under 40 years (63 %). The general background knowledge about SC&TE is low. Respondents confirm that remaining controversies still arise from the confusion that stem cell research coincides with embryo manipulation. Clinicians assume that stem cell research has reached the level of clinical implementation, and accept the risks associated of purposely harvesting fetal amniotic cells. Researchers in contrast are more cautious about both implementation and risks.

CONCLUSION

Professionals in the field of perinatology may benefit of a better background knowledge and information on current SC & TE research. Though clinicians may be less aware of the current state of knowledge, they are open to clinical implementation, whereas dedicated researchers remain cautious. In view of the clinical introduction of SC & TE, purposed designed informative action should be taken and safety studies executed, hence avoid sustaining needless polemics.

Use of human embryonic stem cells and umbilical cord blood stem cells for research and therapy: a prospective survey among health care professionals and patients in Switzerland

BACKGROUND

Scientific progress in the biology of hematopoietic stem cells (HSCs) provides opportunities for advances in therapy for different diseases. While stem cell sources such as umbilical cord blood (UCB) are unproblematic, other sources such as human embryonic stem cells (hESCs) raise ethical concerns.

STUDY DESIGN AND METHODS

In a prospective survey we established the ethical acceptability of collection, research, and therapy with UCB HSCs versus hESCs among health care professionals, pregnant women, patients undergoing in vitro fertilization therapy, parents, and HSC donors and recipients in Switzerland.

RESULTS

There was overall agreement about an ethical justification for the collection of UCB for research and therapy in the majority of participants (82%). In contrast, research and therapy with hESCs was acceptable only by a minority (38% of all responders). The collection of hESCs solely created for HSC collection purposes met overall with the lowest approval rates. Hematologists displayed among the participants the highest acceptance rates for the use of hESCs with 55% for collection, 63% for research, and 73% for therapy.

CONCLUSIONS

This is the first study assessing the perception of hESCs for research and therapy in comparison with UCB HSCs in different target groups that are exposed directly, indirectly, or not at all to stem cell-based medicine. Our study shows that the debate over the legitimacy of embryo-destructive transplantation medicine is far from over as particularly hESC research continues to present an ethical problem to an overwhelming majority among laypersons and even among health care professionals.

Embryo futures and stem cell research: the management of informed uncertainty

In the social worlds of assisted conception and stem cell science, uncertainties proliferate and particular framings of the future may be highly strategic. In this article we explore meanings and articulations of the future using data from our study of ethical and social issues implicated by the donation of embryos to human embryonic stem cell research in three linked assisted conception units and stem cell laboratories in the UK. Framings of the future in this field inform the professional management of uncertainty and we explore some of the tensions this involves in practice. The bifurcation of choices for donating embryos into accepting informed uncertainty or not donating at all was identified through the research process of interviews and ethics discussion groups. Professional staff accounts in this study contained moral orientations that valued ideas such as engendering patient trust by offering full information, the sense of collective ownership of the National Heath Service and publicly funded science and ideas for how donors might be able to give restricted consent as a third option.

Derivation and feeder-free propagation of human embryonic stem cells under xeno-free conditions

BACKGROUND AIMS

Human embryonic stem (hES) cells hold great potential for cell therapy and regenerative medicine because of their pluripotency and capacity for self-renewal. The conditions used to derive and culture hES cells vary between and within laboratories depending on the desired use of the cells. Until recently, stem cell culture has been carried out using feeder cells, and culture media, that contain animal products. Recent advances in technology have opened up the possibility of both xeno-free and feeder-free culture of stem cells, essential conditions for the use of stem cells for clinical purposes. To date, however, there has been limited success in achieving this aim.

METHODS, RESULTS AND CONCLUSIONS

Protocols were developed for the successful derivation of two normal and three specific mutation-carrying (SMC) (Huntington's disease and myotonic dystrophy 1) genomically stable hES cell lines, and their adaptation to feeder-free culture, all under xeno-free conditions.

Constructing an ethical framework for embryo donation to research: is it time for a restricted consent policy?

An Ethics & Policy Workshop was held with 20 invited UK stakeholders to consider whether embryo donors should be able to restrict the future use of human embryonic stem cells (hESCs) created from their embryos. Participants cited tensions between pure altruism and a more reciprocal basis for donation; and between basic research (in which genetic material would never form part of another living being) and treatment applications. Two restriction models were suggested to acknowledge specific ethical issues raised by hESCs' use in research and treatments: (1) a two tier system: hESCs with unrestricted consent could go to the UK Stem Cell Bank; those with restricted consent could be used in individual labs which could guarantee to honour the restrictions, and Bank deposit would not be required. (2) a three category system: restrictions could include (i) basic hESC research; (ii) hESC research and treatment; no gamete derivation (iii) 'unrestricted' hESC research and treatment.

Beyond the 'embryo question': human embryonic stem cell ethics in the context of biomaterial donation in the UK

Discussion about the ethics of human embryonic stem cell (ESC) research in the UK tends to be dominated by the divisive and potentially intractable issue of the moral status of the embryo. This can have the effect of silencing or marginalizing other concerns, especially in the context of public engagement with science in this field. One such area of potential public concern is the donation of oocytes and embryos to stem cell research. Contemporary research on the views of donors and potential donors about a wide range of biomaterials, from solid organs to gametes and bone marrow, is reviewed and used to illustrate the range and types of ethical concerns articulated by this important group of stakeholders. Attitudes to donation are found to vary according to the type of tissue being donated or collected, the purpose for which donation is being sought and the nature of the recipient of the donation. Pertinently, attitudes towards donating oocytes are found to differ in some respects from donation of embryos or fetal tissue. The implications of these findings for ensuring ethically robust informed consent and publicly acceptable sourcing of human biomaterials for stem cell research are then considered.

Safety paradigm: genetic evaluation of therapeutic grade human embryonic stem cells

The use of stem cells for regenerative medicine has captured the imagination of the public, with media attention contributing to rising expectations of clinical benefits. Human embryonic stem cells (hESCs) are the best model for capital investment in stem cell therapy and there is a clear need for their robust genetic characterization before scaling-up cell expansion for that purpose. We have to be certain that the genome of the starting material is stable and normal, but the limited resolution of conventional karyotyping is unable to give us such assurance. Advanced molecular cytogenetic technologies such as array comparative genomic hybridization for identifying chromosomal imbalances, and single nucleotide polymorphism analysis for identifying ethnic background and loss of heterozygosity should be introduced as obligatory diagnostic tests for each newly derived hESC line before it is deposited in national stem cell banks. If this new quality standard becomes a requirement, as we are proposing here, it would facilitate and accelerate the banking process, since end-users would be able to select the most appropriate line for their particular application, thus improving efficiency and streamlining the route to manufacturing therapeutics. The pharmaceutical industry, which may use hESC-derived cells for drug screening, should not ignore their genomic profile as this may risk misinterpretation of results and significant waste of resources.

Consenting futures: professional views on social, clinical and ethical aspects of information feedback to embryo donors in human embryonic stem cell research

This paper reports from an ongoing multidisciplinary, ethnographic study that is exploring the views, values and practices (the ethical frameworks) drawn on by professional staff in assisted conception units and stem cell laboratories in relation to embryo donation for research purposes, particularly human embryonic stem cell (hESC) research, in the UK. We focus here on the connection between possible incidental findings and the circumstances in which embryos are donated for hESC research, and report some of the uncertainties and dilemmas of our staff participants. We explore the views of our study participants in relation to two themes: (1) rights to information and anticipating how donors might be informed about future research findings and (2) occupational work goals and trust.

Derivation of the King's College London human embryonic stem cell lines

Since the derivation of the first human embryonic stem cell (hESC) line in 1998, there has been substantial interest in the potential of these cells for regenerative medicine and cell therapy and in the use of hESCs carrying clinically relevant genetic mutations as models for disease research and therapeutic target identification. There is still a need to improve derivation efficiency and further the understanding of the basic biology of these cells and to develop clinical grade culture systems with the aim of producing cell lines suitable for subsequent manipulation for therapy. The derivation of initial hESC lines at King's College London is discussed here, with focus on derivation methodology. Each of the derivations was distinctive. Although the stage and morphology of each blastocyst were generally similar in each attempt, the behaviour of the colonies was unpredictable; colony morphology and development was different with each attempt. Days 5, 6 and 7 blastocysts were used successfully, and the number of days until appearance of stem-like cells varied from 4 to 14 d. Routine characterisation analyses were performed on three lines, all of which displayed appropriate marker expression and survived cryopreservation-thaw cycles. From the lines discussed, four are at various stages of the deposition process with the UKSCB, one is pending submission and two are unsuitable for banking. Continued open and transparent reporting of results and collaborations will maximise the efficiency of derivation and facilitate the development of standardised protocols for the derivation and early culture of hESC lines.

Report on the donation of supernumerary embryos from fresh IVF and ICSI treatment cycles for human stem cell research

BACKGROUND

Research involving human embryos promises exciting therapeutic advances but raises ethical and moral dilemmas for scientists and potential donors. The aim of this study is to report the proportion of couples donating supernumerary fresh embryos for development of stem cell lines from a single centre and the characteristics of those who donate.

METHODS

Couples undergoing assisted conception treatment in a teaching hospital received research information between January 2005 and July 2006. Counselling and consenting was performed by a dedicated research nurse. Demographic data was collected for couples who enrolled in the study.

MAIN OUTCOME MEASURES

To determine the proportion of couples willing to donate surplus embryos for stem cell derivation and to examine the characteristics of those who consent to donate.

RESULTS

Of 508 couples, 353 (69%) expressed an interest in research on their treatment consent forms. Sixty-six percent of those interested in research and 87% of counselled couples consented to donation. The demographic characteristics of those who agreed to donate were similar to those of all couples attending the unit.

CONCLUSIONS

Approximately half of couples consented to donate under the described system in our centre. Detailed information provision helps the majority of those counselled to proceed to donation.

The fetal tissue economy: from the abortion clinic to the stem cell laboratory

This paper examines the exchange relationships between women undergoing abortion, the clinicians who procure fetal tissue and stem cell scientists in Britain, and argues that the fetal tissue economy is an important dimension of the gendered bioeconomy that underpins stem cell science. In so doing it suggests that the path from the abortion clinic to the stem cell laboratory differs from the route taken by pre-implantation embryos from the in vitro fertilisation clinic in important ways. It reports on a study which included 29 in-depth, semi-structured interviews with stem cell scientists, policymakers, clinicians, activists and sponsors of stem cell research. The paper explores the meanings attached to aborted fetuses and how women's relationship to fetal tissue is constructed in the interviews, the law and official guidance on the use and disposal of fetal tissue. This is linked to variability in consent procedures and procurement practices.

[Human embryonic stem cells within the context of international research activity]

Research involving pluripotent human embryonic stem cells (hESCs) is a rapidly growing field of science. Since hESCs originate from early human embryos, alternative methods for producing pluripotent cells have been developed. This article introduces some of those strategies and, in addition, covers international efforts to establish consistent international standards for cultivation, characterization and preservation of hESCs. Furthermore, global trends to form networks in the field of stem cell research as well as endeavors to harmonize ethical standards for hESC research are presented. Finally, potential applications of hESCs in the field of pharmacology/toxicology are discussed as well as recent results of animal studies using hESCs.