Cloning and stem cells

2010 ◽  
pp. 73-90
Author(s):  
Carlo Alberto Redi ◽  
Manuela Monti

Cloning, the generation of genetically identical individuals, frequently occurs in plants and in several animal groups. Nowadays cloning is technically reproducible thanks to both embryo splitting and somatic cell nuclear transfer thus playing an important role in zootechnical applications (i.e., to increase transgenic animals for drug production) and in biomedicine (i.e, to produce embryonic stem cells in animal models, cybrids, etc.). The relevant historical advancements of these techniques and the related ethical issues are discussed. A brief review of the formation of a new individual as "a process" clearly leads to the impossibility for the biologist to unambiguously determine at which stage a new individual is first formed. However, the application of the scientific method to this issue produces a communal statement independent from ideological or religious opinion: ontogenetically, the material-energetic process originating and identifying a new individual is coincident with the moment in which the first genetically active copy of his genome is formed. Even the critical production of patient-specific stem cells (therapeutic cloning) it is most likely to be superseded and devoided of any ethical concerns thanks to the technical advancements developed by Shinia Yamanaka on the genetic reprogramming of terminally differentiated nuclei. The production of specific cell types might address the therapy of nearly all the pathologies. Noteworthy, starting April 2009 but actually beginning August 2010, the FDA gave green light to the first trial based on the administration of neuronal cells derived from human embryonic stem cells to 11 patients with severe spinal cord injury. Bio-political topics are briefly frameworked within the elaboration of ethical principles and laws that respect multiple values, which are necessary in multi-ethnic cultures.

2001 ◽  
Vol 13 (8) ◽  
pp. 523 ◽  
Author(s):  
Alan O. Trounson

Human embryonic stem cells lines can be derived from human blastocysts at high efficiency (>50%) by immunosurgical isolation of the inner cell mass and culture on embryonic fibroblast cell lines. These cells will spontaneously differentiate into all the primary embryonic lineages in vitro and in vivo, but they are unable to form an integrated embryo or body plan by themselves or when combined with trophectoderm cells. They may be directed into a number of specific cell types and this enrichment process requires specific growth factors, cell-surface molecules, matrix molecules and secreted products of other cell types. Embryonic stem (ES) cells are immortal and represent a major potential for cell therapies for regenerative medicine. Their use in transplantation may depend on the formation of a large bank of suitable human leucocyte antigen (HLA) types or the genetic erasure of their HLA expression. Successful transplantation may also require induction of tolerance in recipients and ongoing immune suppression. Although it is possible to customize ES cells by therapeutic cloning or cytoplasmic transfer, it would appear unlikely that these strategies will be used extensively for producing ES cells compatible for transplantation. Embryonic stem cell research may deliver a new pathway for regenerative medicine.


1998 ◽  
Vol 10 (1) ◽  
pp. 121 ◽  
Author(s):  
A. Trounson ◽  
M. Pera

The successful cloning of a mammal from an adult somatic cell nucleus opens new avenues for major advances in reproductive medicine, biotechnology and cellular-based transplantation therapies for degenerative diseases. At the same time, this breakthrough has generated much heated discussion concerning the ethics of cloning. Twinning is a form of cloning, and there are instances in clinical assisted reproduction in which the deliberate formation of twins by embryo dissection would seem ethically acceptable. Nuclear transfer technology might facilitate the derivation of human embryonic stem cells, capable of differentiation into a wide variety of somatic cell lineages. Directed differentiation of human embryonic stem cells into specific cell types in vitro could provide a universal source of cells for transplantation therapy. The potential benefits of therapeutics based on cloning technologies are considerable, and hasty legislation to ban all such procedures could block progress in critical arenas of biomedical research


2018 ◽  
Vol 17 (1) ◽  
Author(s):  
Che Anuar Che Mohamad ◽  
Abdurezak Abdullahi Hashi

The advancement in human stem cell research has promised a viable alternative treatment for a range of ‘incurable diseases’ such as neurological diseases. To date, several studies have documented substantial evidences on the therapeutic properties of stem cells in promoting repair in different diseases including common neurological disorders i.e. ischaemic stroke and spinal cord injury. However, the progress of stem cell research has been surrounded by ethical issues which largely due to the usage of human embryos as one of the sources. These embryonic stem cells which originally derived from human embryo of aborted foetus or already existing human embryonic stem cells (hESCs) lines, has sparked an intense moral and religious argument among people of various faith, including Muslim community. From the therapeutic point of view, amongst the currently available stem cells, hESCs show the greatest potential for the broadest range of cell replacement therapies and are regarded as the most commercially viable. This review focuses on the major ethical issues, particularly to Muslim community, related to human embryonic stem cells research with special emphasis on the moral status of the embryo and the beginning of life according to the Islamic ethics and rulings. In this paper, we also discuss some ethical positions towards embryonic stem cell research in the Islamic world, including official regulations existing in some Muslim countries. We examine the justification and the necessity on the usage of hESCs following the newly discovered Induced Pluripotent Stem Cells (IPSCs) in the laboratory. In addition, we supplement the discussions with the general views and positions from the other two Abrahamic religions i.e. Christianity and Judaism.


Blood ◽  
2006 ◽  
Vol 107 (4) ◽  
pp. 1265-1275 ◽  
Author(s):  
Abby L. Olsen ◽  
David L. Stachura ◽  
Mitchell J. Weiss

Embryonic stem (ES) cells exhibit the remarkable capacity to become virtually any differentiated tissue upon appropriate manipulation in culture, a property that has been beneficial for studies of hematopoiesis. Until recently, the majority of this work used murine ES cells for basic research to elucidate fundamental properties of blood-cell development and establish methods to derive specific mature lineages. Now, the advent of human ES cells sets the stage for more applied pursuits to generate transplantable cells for treating blood disorders. Current efforts are directed toward adapting in vitro hematopoietic differentiation methods developed for murine ES cells to human lines, identifying the key interspecies differences in biologic properties of ES cells, and generating ES cell-derived hematopoietic stem cells that are competent to repopulate adult hosts. The ultimate medical goal is to create patient-specific and generic ES cell lines that can be expanded in vitro, genetically altered, and differentiated into cell types that can be used to treat hematopoietic diseases.


Cancers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 663
Author(s):  
Kwang-Hyun Baek ◽  
Jihye Choi ◽  
Chang-Zhu Pei

Octamer-binding transcription factor 3/4 (OCT-3/4), which is involved in the tumorigenesis of somatic cancers, has diverse functions during cancer development. Overexpression of OCT-3/4 has been detected in various human somatic tumors, indicating that OCT-3/4 activation may contribute to the development and progression of cancers. Stem cells can undergo self-renewal, pluripotency, and reprogramming with the help of at least four transcription factors, OCT-3/4, SRY box-containing gene 2 (SOX2), Krüppel-like factor 4 (KLF4), and c-MYC. Of these, OCT-3/4 plays a critical role in maintenance of undifferentiated state of embryonic stem cells (ESCs) and in production of induced pluripotent stem cells (iPSCs). Stem cells can undergo partitioning through mitosis and separate into specific cell types, three embryonic germ layers: the endoderm, the mesoderm, and the trophectoderm. It has been demonstrated that the stability of OCT-3/4 is mediated by the ubiquitin-proteasome system (UPS), which is one of the key cellular mechanisms for cellular homeostasis. The framework of the mechanism is simple, but the proteolytic machinery is complicated. Ubiquitination promotes protein degradation, and ubiquitination of OCT-3/4 leads to regulation of cellular proliferation and differentiation. Therefore, it is expected that OCT-3/4 may play a key role in proliferation and differentiation of proliferating cells.


2020 ◽  
Author(s):  
Tee Udomlumleart ◽  
Sofia Hu ◽  
Salil Garg

AbstractPluripotent embryonic stem cells (ESCs) contain the ability to constitute the cell types of the adult vertebrate through a series of developmental state transitions. In culture, ESCs reversibly transition between states in a manner previously described as stochastic. However, whether ESCs retain memory of their previous states or transition in a memoryless (Markovian) process remains relatively unknown. Here we show lineages of ESCs do not exhibit the Markovian property: their previous states and kin relations influence future choices. In a subset of lineages, related ESCs remain likely to occupy the same state weeks after labeling. Unexpectedly, the distribution of lineages across states away from the equilibrium point predicted by a Markov model remains consistent over time, suggesting a conservation of informational entropy in this system. Additionally, some lineages appear highly dynamic in their ability to switch states but do not dominate the culture, suggesting that state switching is a separable property from growth. Together, these data suggest ESC state transitions are a proscribed process governed by additional variables.


2020 ◽  
Vol 5 (1) ◽  
pp. 1-4 ◽  
Author(s):  
David Septian Sumanto Marpaung ◽  
Ayu Oshin Yap Sinaga

The four transcription factors OCT4, SOX2, KLF4 and c-MYC are highly expressed in embryonic stem cells (ESC) and their overexpression can induce pluripotency, the ability to differentiate into all cell types of an organism. The ectopic expression such transcription factors could reprogram somatic stem cells become induced pluripotency stem cells (iPSC), an embryonic stem cells-like. Production of recombinant pluripotency factors gain interests due to high demand from generation of induced pluripotent stem cells in regenerative medical therapy recently. This review will focus on demonstrate the recent advances in recombinant pluripotency factor production using various host.


2021 ◽  
Vol 26 ◽  
pp. 169-191
Author(s):  
Emma E. Redfield ◽  
Erin K. Luciano ◽  
Monica J. Sewell ◽  
Lucas A. Mitzel ◽  
Isaac J. Sanford ◽  
...  

This study looks at the number of clinical trials involving specific stem cell types. To our knowledge, this has never been done before. Stem cell clinical trials that were conducted at locations in the US and registered on the National Institutes of Health database at ‘clinicaltrials.gov’ were categorized according to the type of stem cell used (adult, cancer, embryonic, perinatal, or induced pluripotent) and the year that the trial was registered. From 1999 to 2014, there were 2,357 US stem cell clinical trials registered on ‘clinicaltrials.gov,’ and 89 percent were from adult stem cells and only 0.12 percent were from embryonic stem cells. This study concludes that embryonic stem cells should no longer be used for clinical study because of their irrelevance, moral questions, and induced pluripotent stem cells.


2020 ◽  
pp. 185-208
Author(s):  
John Parrington

Stem cells, which are ‘immortal’ cells that divide indefinitely and produce many different cell types, are central to how our body develops and maintains itself. Embryonic stem cells can give rise to all cell types in the body, and there has been lots of interest since their discovery in the 1980s in using such cells to generate new tissues or organs to replace diseased or faulty ones. More recently has come the discovery of induced pluripotent stem cells, which are normal skin cells taken from a person and genetically modified or tweaked chemically to give them stem cell properties. There is now hope that both of these types of stem cells might be used in ‘regenerative’ medicine, for instance in producing pancreatic cells that secrete insulin which could be used to treat diabetes. Perhaps the most remarkable breakthrough in recent years has been the discovery that stem cells introduced into a 3D matrix that is infused with chemicals that stimulate the development of particular cell types, can spontaneously form ‘organoids’, which have many of the cell types and even structural features of human organs such as hearts, kidneys, intestines, and even eyes and brains. Organoids make it possible to study how human organs develop but also this area of science raises many ethical issues. For instance, currently human brain organoids can only grow to the size of an embryonic brain, but if in the future they could be induced to grow to adult brain size, could they develop feelings and thoughts?


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