scholarly journals Generation of donor organs in chimeric animals via blastocyst complementation

2020 ◽  
Vol 24 (8) ◽  
pp. 913-921
Author(s):  
T. I. Babochkina ◽  
L. A. Gerlinskaya ◽  
M. P. Moshkin
Keyword(s):  
Developmental Stages ◽  
Successful Implementation ◽  
Host Animal ◽  
Human Donor ◽  
Human Organs ◽  
Blastocyst Complementation ◽  
Donor Cells ◽  
Induced Pluripotent ◽  
Medicine Today ◽  
Genomic Editing

The lack of organs for transplantation is an important problem in medicine today. The growth of organs in chimeric animals may be the solution of this. The proposed technology is the interspecific blastocyst complementation method in combination with genomic editing for obtaining “free niches” and pluripotent stem cell production methods. The CRISPR/Cas9 method allows the so-called “free niches” to be obtained for blastocyst complementation. The technologies of producing induced pluripotent stem cells give us the opportunity to obtain human donor cells capable of populating a “free niche”. Taken together, these technologies allow interspecific blastocyst complementation between humans and other animals, which makes it possible in the future to grow human organs for transplantations inside chimeric animals. However, in practice, in order to achieve successful interspecific blastocyst complementation, it is necessary to solve a number of problems: to improve methods for producing “chimeric competent” cells, to overcome specific interspecific barriers, to select compatible cell developmental stages for injection and the corresponding developmental stage of the host embryo, to prevent apoptosis of donor cells and to achieve effective proliferation of the human donor cells in the host animal. Also, it is very important to analyze the ethical aspects related to developing technologies of chimeric organisms with the participation of human cells. Today, many researchers are trying to solve these problems and also to establish new approaches in the creation of interspecific chimeric organisms in order to grow human organs for transplantation. In the present review we described the historical stages of the development of the blastocyst complementation method, examined in detail the technologies that underlie modern blastocyst complementation, and analyzed current progress that gives us the possibility to grow human organs in chimeric animals. We also considered the barriers and issues preventing the successful implementation of interspecific blastocyst complementation in practice, and discussed the further development of this method.

scholarly journals The road to generating transplantable organs: from blastocyst complementation to interspecies chimeras

Development ◽  
2021 ◽  
Vol 148 (12) ◽  
Author(s):  
Canbin Zheng ◽  
Emily B. Ballard ◽  
Jun Wu
Keyword(s):  
Science Fiction ◽  
Pluripotent Stem Cells ◽  
Current Status ◽  
Divergent Evolution ◽  
Closely Related Species ◽  
The Road ◽  
Human Organs ◽  
Blastocyst Complementation ◽  
Donor Cells ◽  
Host Embryo

ABSTRACT Growing human organs in animals sounds like something from the realm of science fiction, but it may one day become a reality through a technique known as interspecies blastocyst complementation. This technique, which was originally developed to study gene function in development, involves injecting donor pluripotent stem cells into an organogenesis-disabled host embryo, allowing the donor cells to compensate for missing organs or tissues. Although interspecies blastocyst complementation has been achieved between closely related species, such as mice and rats, the situation becomes much more difficult for species that are far apart on the evolutionary tree. This is presumably because of layers of xenogeneic barriers that are a result of divergent evolution. In this Review, we discuss the current status of blastocyst complementation approaches and, in light of recent progress, elaborate on the keys to success for interspecies blastocyst complementation and organ generation.

scholarly journals Umbilical Cord Tissue as a Source of Young Cells for the Derivation of Induced Pluripotent Stem Cells Using Non-Integrating Episomal Vectors and Feeder-Free Conditions

Cells ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 49
Author(s):  
Aisha Mohamed ◽  
Theresa Chow ◽  
Jennifer Whiteley ◽  
Amanda Fantin ◽  
Kersti Sorra ◽  
...  
Keyword(s):  
Stem Cells ◽  
Induced Pluripotent Stem Cells ◽  
Umbilical Cord ◽  
Pluripotent Stem Cells ◽  
Blood Cells ◽  
Growth Media ◽  
Donor Cells ◽  
Episomal Vectors ◽  
Umbilical Cord Tissue ◽  
Induced Pluripotent

The clinical application of induced pluripotent stem cells (iPSC) needs to balance the use of an autologous source that would be a perfect match for the patient against any safety or efficacy issues that might arise with using cells from an older patient or donor. Drs. Takahashi and Yamanaka and the Office of Cellular and Tissue-based Products (PMDA), Japan, have had concerns over the existence of accumulated DNA mutations in the cells of older donors and the possibility of long-term negative effects. To mitigate the risk, they have chosen to partner with the Umbilical Cord (UC) banks in Japan to source allogeneic-matched donor cells. Production of iPSCs from UC blood cells (UCB) has been successful; however, reprogramming blood cells requires cell enrichment with columns or flow cytometry and specialized growth media. These requirements add to the cost of production and increase the manipulation of the cells, which complicates the regulatory approval process. Alternatively, umbilical cord tissue mesenchymal stromal cells (CT-MSCs) have the same advantage as UCB cells of being a source of young donor cells. Crucially, CT-MSCs are easier and less expensive to harvest and grow compared to UCB cells. Here, we demonstrate that CT-MSCs can be easily isolated without expensive enzymatic treatment or columns and reprogramed well using episomal vectors, which allow for the removal of the reprogramming factors after a few passages. Together the data indicates that CT-MSCs are a viable source of donor cells for the production of clinical-grade, patient matched iPSCs.

Regenerating Life

2020 ◽  
pp. 185-208
Author(s):  
John Parrington
Keyword(s):  
Stem Cells ◽  
Ethical Issues ◽  
Brain Size ◽  
Embryonic Stem ◽  
Cell Types ◽  
Structural Features ◽  
Human Organs ◽  
3D Matrix ◽  
Immortal Cells ◽  
Induced Pluripotent

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?

scholarly journals NaV1.5 knockout in iPSCs: a novel approach to study NaV1.5 variants in a human cardiomyocyte environment

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marion Pierre ◽  
Mohammed Djemai ◽  
Hugo Poulin ◽  
Mohamed Chahine
Keyword(s):  
Contractile Activity ◽  
Somatic Tissue ◽  
Patient Specific ◽  
Ipsc Line ◽  
Healthy Human ◽  
Novel Approach ◽  
Electrophysiological Recordings ◽  
Cardiac Sodium Channel ◽  
Induced Pluripotent ◽  
Genomic Editing

AbstractCardiomyocytes derived from patient-specific induced pluripotent stem cells (iPSC-CMs) successfully reproduce the mechanisms of several channelopathies. However, this approach involve cell reprogramming from somatic tissue biopsies or genomic editing in healthy iPSCs for every mutation found and to be investigated. We aim to knockout (KO) NaV1.5, the cardiac sodium channel, in a healthy human iPSC line, characterize the model and then, use it to express variants of NaV1.5. We develop a homozygous NaV1.5 KO iPSC line able to differentiate into cardiomyocytes with CRISPR/Cas9 tool. The NaV1.5 KO iPSC-CMs exhibited an organized contractile apparatus, spontaneous contractile activity, and electrophysiological recordings confirmed the major reduction in total Na+ currents. The action potentials (APs) exhibited a reduction in their amplitude and in their maximal rate of rise. Voltage optical mapping recordings revealed that the conduction velocity Ca2+ transient waves propagation velocities were slow. A wild-type (WT) NaV1.5 channel expressed by transient transfection in the KO iPSC-CMs restored Na+ channel expression and AP properties. The expression of NaV1.5/delQKP, a long QT type 3 (LQT3) variant, in the NaV1.5 KO iPSC-CMs showed that dysfunctional Na+ channels exhibited a persistent Na+ current and caused prolonged AP duration that led to arrhythmic events, characteristics of LQT3.

scholarly journals Double sperm cloning (DSC) is a promising strategy in mammalian genetic engineering and stem cell research

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhi-ping Zhang ◽  
Jun-tao Zhang ◽  
Shu-cheng Huang ◽  
Xiu-yuan He ◽  
Li-xin Deng
Keyword(s):  
Stem Cells ◽  
Regenerative Medicine ◽  
Epigenetic Modification ◽  
Embryonic Stem ◽  
Immunological Response ◽  
Epigenetic Memory ◽  
Donor Cells ◽  
Induced Pluripotent ◽  
The Many ◽  
Artificial Activation

Abstract Embryonic stem cells (ESCs) derived from somatic cell nuclear transfer (SCNT) and induced pluripotent stem cells (iPSCs) are promising tools for meeting the personalized requirements of regenerative medicine. However, some obstacles need to be overcome before clinical trials can be undertaken. First, donor cells vary, and the reprogramming procedures are diverse, so standardization is a great obstacle regarding SCNT and iPSCs. Second, somatic cells derived from a patient may carry mitochondrial DNA mutations and exhibit telomere instability with aging or disease, and SCNT-ESCs and iPSCs retain the epigenetic memory or epigenetic modification errors. Third, reprogramming efficiency has remained low. Therefore, in addition to improving their success rate, other alternatives for producing ESCs should be explored. Producing androgenetic diploid embryos could be an outstanding strategy; androgenic diploid embryos are produced through double sperm cloning (DSC), in which two capacitated sperms (XY or XX, sorted by flow cytometer) are injected into a denucleated oocyte by intracytoplasmic sperm injection (ICSI) to reconstruct embryo and derive DSC-ESCs. This process could avoid some potential issues, such as mitochondrial interference, telomere shortening, and somatic epigenetic memory, all of which accompany somatic donor cells. Oocytes are naturally activated by sperm, which is unlike the artificial activation that occurs in SCNT. The procedure is simple and practical and can be easily standardized. In addition, DSC-ESCs can overcome ethical concerns and resolve immunological response matching with sperm providers. Certainly, some challenges must be faced regarding imprinted genes, epigenetics, X chromosome inactivation, and dosage compensation. In mice, DSC-ESCs have been produced and have shown excellent differentiation ability. Therefore, the many advantages of DSC make the study of this process worthwhile for regenerative medicine and animal breeding.

Homing of Human Cells in the Fetal Sheep Model: Modulation by Antibodies Activating or Inhibiting Very Late Activation Antigen-4–Dependent Function

Blood ◽  
1999 ◽  
Vol 94 (7) ◽  
pp. 2515-2522 ◽  
Author(s):  
Esmail D. Zanjani ◽  
Alan W. Flake ◽  
Graça Almeida-Porada ◽  
Nam Tran ◽  
Thalia Papayannopoulou
Keyword(s):  
Molecular Mechanisms ◽  
Fetal Liver ◽  
In Utero ◽  
Human Cells ◽  
Human Donor ◽  
Sheep Model ◽  
Fetal Sheep ◽  
In Utero Transplantation ◽  
Donor Cells ◽  
Activation Antigen

The mechanisms by which intravenously (IV)-administered hematopoietic cells home to the bone marrow (BM) are poorly defined. Although insightful information has been obtained in mice, our knowledge about homing of human cells is very limited. In the present study, we investigated the importance of very late activation antigen (VLA)-4 in the early phases of lodgment of human CD34+progenitors into the sheep hematopoietic compartment after in utero transplantation. We have found that preincubation of donor cells with anti–VLA-4 blocking antibodies resulted in a profound reduction of human cell lodgment in the fetal BM at 24 and 48 hours after transplantation, with a corresponding increase of human cells in the peripheral circulation. Furthermore, IV infusion of the anti–VLA-4 antibody at later times (posttransplantation days 21 to 24) resulted in redistribution or mobilization of human progenitors from the BM to the peripheral blood. In an attempt to positively modulate homing, we also pretreated human donor cells with an activating antibody to β1 integrins. This treatment resulted in increased lodgment of donor cells in the fetal liver, presumably for hemodynamic reasons, at the expense of the BM. Given previous involvement of the VLA-4/vascular cell adhesion molecule (VCAM)-1 adhesion pathway in homing and mobilization in the murine system, our present data suggest that cross-reacting ligands (likely VCAM-1) for human VLA-4 exist in sheep BM, thereby implicating conservation of molecular mechanisms of homing and mobilization across disparate species barriers. Thus, information from xenogeneic models of human hematopoiesis and specifically, the human/sheep model of in utero transplantation, may provide valuable insights into human hematopoietic transplantation biology.

Human hematopoiesis in murine embryos after injecting human cord blood–derived hematopoietic stem cells into murine blastocysts

Blood ◽  
2002 ◽  
Vol 99 (2) ◽  
pp. 719-721 ◽  
Author(s):  
Friedrich Harder ◽  
Reinhard Henschler ◽  
Ilse Junghahn ◽  
Marinus C. Lamers ◽  
Albrecht M. Müller
Keyword(s):  
Stem Cells ◽  
Hematopoietic Stem Cells ◽  
Cord Blood ◽  
Developmental Stages ◽  
Specific Gene ◽  
Human Cord Blood ◽  
Human Donor ◽  
Fetal Sheep ◽  
Hematopoietic Stem ◽  
Murine Embryos

Abstract At different developmental stages, candidate human hematopoietic stem cells (HSCs) are present within the CD34+ CD38− population. By means of xenotransplantation, such CD34+CD38− cells were recently shown to engraft the hematopoietic system of fetal sheep and nonobese diabetic severe combined immunodeficient adult mice. Here it is demonstrated that, after their injection into murine blastocysts, human cord blood (CB)–derived CD34+and CD34+ CD38− cells repopulate the hematopoietic tissues of nonimmunocompromised murine embryos and that human donor contribution can persist to adulthood. It is further observed that human hematopoietic progenitor cells are present in murine hematopoietic tissues of midgestational chimeric embryos and that progeny of the injected human HSCs activate erythroid-specific gene expression. Thus, the early murine embryo provides a suitable environment for the survival and differentiation of human CB CD34+ CD38− cells.

scholarly journals Clinically compatible differentiation protocol for human pluripotent stem cell-derived dopaminergic progenitor cells

2020 ◽  
Author(s):  
Daisuke Doi ◽  
Tetsuhiro Kikuchi ◽  
Asuka Morizane ◽  
Jun Takahashi
Keyword(s):  
Stem Cells ◽  
Progenitor Cells ◽  
Pluripotent Stem Cells ◽  
Culture Cell ◽  
Cell Replacement Therapy ◽  
High Density Culture ◽  
Differentiation Protocol ◽  
Donor Cells ◽  
A Cell ◽  
Induced Pluripotent

Abstract Cell replacement therapy with human pluripotent stem cells has the potential to be a new therapy for Parkinson’s disease (PD). This protocol induces human induced pluripotent stem cells (iPSCs) to dopaminergic progenitor cells (DAPs) as clinically compatible donor cells in 30 days. The protocol includes starting with high density culture, cell sorting by using a cell surface marker for floor plate, and a maturation culture to form floating aggregates. The DAPs differentiated with this protocol were used in a pre-clinical tumorigenicity and efficacy study aiming for approval to start a clinical trial in Japan.

scholarly journals Bioprinting Technology as a Legal Challenge: Determining the Model of Legal Regulation

Lex Russica ◽  
2019 ◽  
pp. 80-91
Author(s):  
D. E. Bogdanov
Keyword(s):  
Stem Cells ◽  
3D Printing ◽  
3D Models ◽  
Physical World ◽  
Legal Regulation ◽  
Material World ◽  
Human Organs ◽  
Differentiated Cells ◽  
The Creation ◽  
Induced Pluripotent

The technology of 3D printing creates serious challenges to the legal system that in its development is lagging behind scientific and technological progress. The development of 3D printing technology leads to the «digitalization» of objects of the material world when the boundaries between the physical world and the digital space are blurred. If 3D printing digitalizes objects of the material world, bioprinting digitalizes the human body. An individual tends to depend on the digital incarnation of his body or its individual organs in the corresponding electronic 3D models.Bioprinting is aimed at the formation of a new medical paradigm that will result in overcoming the deficiency of human organs and tissues in the field of transplantology. The discovery of the possibility of reprogramming differentiated cells and obtaining induced pluripotent stem cells eliminates the ethical and legal problem associated with the use of stem cells of the embryo. This should be taken into account in the development of a model of legal regulation of relations connected with the creation of bio-print human organs.Bioprint organs are synthetic organs, so the relations associated with their creation and implantation need independent legal regulation. Contemporary transplantology legislation and bans and prohibitions contained in it do not take into account the features of the creation of organs through 3D bioprinting. It is acceptable to commercialize relations in the field of bioprinting, to perform non-gratuitous transactions in this area, as well as to permit limited turnover of «bioprinting» organs subjecting them to the regulation applied to any other objects of civil law. Legislation on biomedical cellular products is also not able to regulate relations related to the creation and implantation of bio-printed human organs. Thus, the need arises to adopt a special legislative act aimed at regulating relations at all stages of the use of bioprinting technology.

scholarly journals Developmental Stages of Hypopygiopsis violacea (Family: Calliphoridae), a Forensically Important Blowfly on Rat Carcass

1970 ◽  
Vol 5 (1) ◽  
pp. 26-33
Author(s):  
Mohd Zacaery Khalik ◽  
Adibah Mohamed Shariff ◽  
Wan Nurainie Wan Ismail
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Small Mammal ◽  
Larval Stage ◽  
Developmental Stages ◽  
Time Of Death ◽  
Host Animal ◽  
Developmental Duration ◽  
Rate Of Development ◽  
Decomposition Stages

A study on blowfly developmental stages to estimate the time of death (TOD) of small mammal had been conducted during a rainy season. During this study, fresh Muller’s rat (Sundamys muelleri) carcasses were used as the host sample, and the developmental duration of every larval stage, decomposition stages of host animal, ambient temperature and relative humidity were recorded. Hypopygiopsis violacea (Family: Calliphoridae) was recorded to be the first blowfly visiting and ovipositing on the carcass after the carcass being deposited, while Chrysomya megacephala and C. ruffacies were recorded as the most dominant calliphorids present during the decomposition process. This study estimated that the time for calliphorids to complete their life cycle, from an egg to an adult was approximately twenty-three days, and the decomposition of Sundamys muelleri took about nine days. Useful information on succession and rate of development of blowfly could enhance the knowledge of the length of time elapsed since death in particular host animal.

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