383 IDENTIFICATION OF PLURIPOTENCY MARKERS IN SWINE EMBRYOS

2010 ◽  
Vol 22 (1) ◽  
pp. 348
Author(s):  
F. R. O. de Barros ◽  
M. D. Goissis ◽  
M. G. Marques ◽  
M. I. Giassetti ◽  
F. F. Paula-Lopes ◽  
...  
Keyword(s):  
Stem Cells ◽  
In Vitro Culture ◽  
Genetic Manipulation ◽  
Embryonic Stem ◽  
Culture Conditions ◽  
Rabbit Serum ◽  
Embryonic Fibroblasts ◽  
Pluripotency Markers

Embryonic stem cells (ESC) are a useful tool for studying embryonic development, cell differentiation, and genetic manipulation. Moreover, these cells can be applied in cell-based therapies and in vitro organogenesis. The research conducted with human ESC has generated many ethical, moral, and religious considerations by scientists and laymen alike. Therefore, an animal model such as the pig (Sus scrofa) is valuable in overcoming such hurdles because this species holds physiologic parameters similar to humans. In spite of the great biomedical potential of ESC, many difficulties have been faced in maintaining these cells in a pluripotent state in vitro. For this reason, studies to elucidate the mechanisms of in vitro maintenance of undifferentiated ESC are needed to improve the culture of these cells. The objectives of this study were (1) to isolate ESC from in vitro- and in vivo-produced swine blastocysts; (2) to compare 2 in vitro culture conditions to maintain isolated inner cell masses (ICM), murine embryonic fibroblasts (MEF), or Matrigel; and (3) to identify and to compare the expression of the pluripotency markers Nanog, Sox2, and FoxD3 at ESC and in vitro- and in vivo-produced swine blastocysts. In this manner, swine blastocysts were obtained by in vitro maturation and fertilization of oocytes from ovaries collected in abattoirs. Embryos were in vitro cultured for 7 days until blastocyst stage. In addition, in vivo-produced blastocysts were obtained by superovulation followed by AI of gilts (150 days of age). Embryos were collected by post-mortem uterus flushing 5 days after ovulation. In vitro- and in vivo-produced blastocysts were submitted to immunosurgery to isolate the ICM. Briefly, zona pellucida was digested with pronase solution, and embryos were incubated with anti-swine rabbit serum to remove trophoectoderm cells and with guinea-pig complement serum. Resultant ICM (14 and 66 ICM from in vitro- and in vivo-produced blastocysts, respectively) were cultured in stem cells media (GMEM added by 15% FCS, 0.1 mM β-mercaptoethanol, 1% nonessential amino acids, and 4 ng mL-1 of basic fibroblast growth factor) over monolayer of irradiated mouse embryonic fibroblasts (MEF) or Matrigel for 3 weeks. No difference was observed between the in vitro culture conditions (MEF and Matrigel) on isolated ICM adhesion. In addition, no difference was verified between in vitro- and in vivo-produced blastocysts on adhesion of cultured ICM. However, no swine ESC was obtained. Gene expression analysis was performed only with whole in vitro- and in vivo-produced blastocysts. Results showed that Nanog and Sox2 were less expressed in in vitro-produced blastocysts. However, the expression of FoxD3, demonstrated in this study for the first time, was similar between groups. Because no ESC lineage was obtained in swine until now, we believe this species has different requirements compared with murine and human. Therefore, more studies are necessary to establish protocols to isolate porcine ESC. Acknowledgments are given to FAPESP (processes 06/58507-0 and 07/51732-0).

391 A COMPARATIVE GENE EXPRESSION ANALYSIS BETWEEN SHEEP EARLY EMBRYONIC DEVELOPMENT AND PUTATIVE EMBRYONIC STEM CELLS

2010 ◽  
Vol 22 (1) ◽  
pp. 352
Author(s):  
B. M. Murray ◽  
S. Schmoelzl ◽  
N. M. Andronicos ◽  
J. R. Hill ◽  
P. J. Verma ◽  
...  
Keyword(s):  
Gene Expression ◽  
Stem Cells ◽  
Embryonic Stem Cells ◽  
In Vitro Culture ◽  
Culture Media ◽  
Embryonic Stem ◽  
Oct4 Expression ◽  
Pluripotency Markers

The optimization of culture media to support the isolation of embryonic stem cells relies on methods to monitor whether the pluripotent state of the cultured cells has been maintained. We developed a panel of gene expression assays that allowed us to correlate molecular measures of pluripotency or lineage differentiation with a developmental time course. By conducting quantitative PCR analysis of sheep embryos over Day 6.5 to 24 and sheep inner cell mass (ICM) cells cultured over 25 days, we tested whether culture media designed to inhibit differentiation are able to maintain sheep ICM cells in a pluripotent state. Briefly, embryos were collected from Merino ewes (n = 50, 3 years) at Day 6.5, 12, 16, 20, and 24 post-AI. Embryos were collected from the dissected uterine tracts of slaughtered ewes, excluding Day 6.5 blastocysts, which were surgically recovered from superovulated ewes. For the in vitro culture, Day 6.5 ICM cells were isolated by immunosurgery and cultured on mitomycin-C-treated mouse embryonic fibroblasts in an inhibitor-based medium (3i, based on Ying Q-L et al. 2008 Nature 453, 519-523). Real-time PCR assays for pluripotency (OCT4, SOX2, NANOG) and differentiation (ectodermal: FGF5, PAX6; endodermal: GATA4, GATA6, Somatostatin; mesodermal: BMP4, Connexin40) of sheep candidate genes were conducted on cDNA prepared from these samples and normalized against the reference genes RPL19 and RPS26. In in vivo embryos, pluripotency markers OCT4, SOX2, and NANOG all decreased between Day 6.5 and Day 20, although OCT4 expression spiked around Day 16. More interestingly, pluripotency expression decreased during in vitro culture, with NANOG expression completely lost by passage 2 at Day 11 and OCT4 expression at an equivalent Day 24 embryo basal level by Day 14. The endodermal markers GATA6 and GATA4 decreased between Day 6.5 and Day 12, respectively, although in vitro GATA4 was only expressed once at Day 7. In vivo FGF5 and both PAX6 and Somatostatin displayed a delayed onset, increasing expression from Day 16 and 20, respectively, whereas the ectodermal markers were already expressed by Day 7 in vitro. Both mesodermal markers Connexin40 and BMP4 presented minor fold changes in both data sets. In conclusion, this study has verified the primer sets and described a sheep in vivo embryo gene expression profile comprising both pluripotent and differentiation candidates. Furthermore, the decrease of pluripotency markers together with the appearance of differentiation markers during in vitro culture of ICM cells suggest that culturing ICM cells in 3i media is not sufficient to maintain a sheep-specific pluripotent population of cells. Therefore, future studies will be aimed at manipulating the current in vitro system to focus on maintaining pluripotent genes such as NANOG and OCT4 in culture.

scholarly journals Dynamics of anteroposterior axis establishment in a mammalian embryo-like system

2021 ◽  
Author(s):  
Kerim Anlaş ◽  
Nicola Gritti ◽  
David Oriola ◽  
Krisztina Arató ◽  
Fumio Nakaki ◽  
...  
Keyword(s):  
Stem Cells ◽  
Symmetry Breaking ◽  
Marker Gene ◽  
Embryonic Stem ◽  
Culture Conditions ◽  
Body Plan ◽  
Germ Layer ◽  
Mammalian Embryo

1.AbstractIn the mammalian embryo, specification of the anteroposterior (AP) axis demarcates one of the first steps of body plan formation. While this process requires interactions with extra-embryonic tissues in the native embryo, minimal in vitro systems from embryonic stem cells (ESCs) undergo initial AP polarization in the absence of any localized, external cues. This self-organizing potential of stem cells remains not well understood. Here, we study such an initial symmetry breaking event in gastruloids, an established in vitro model for mammalian body plan formation, using the mesodermal marker gene Brachyury or T (Bra/T) to denote the onset of AP axis specification and concomitant germ layer formation. Through aggregate fusion experiments and manipulation of initial culture conditions as well as key developmental signalling pathways, we probe the dynamics of Bra/T polarization. We further conduct single-cell (sc) RNA sequencing of gastruloids at early stages to identify incipient molecular signatures of germ layer commitment and differences between Bra/T+ and Bra/T− populations during as well as after symmetry breaking. Moreover, we transcriptionally compare early development of gastruloids to the mouse embryo and conclude that gastruloids reproducibly undergo AP axis and germ layer specification in a parallel, but distinct manner: While their primed pluripotent cell populations adopt a more mesenchymal state in lieu of an epithelial epiblast-like transcriptome, the emerging mesendodermal lineages in vitro are nevertheless similar to their in vivo equivalents. Altogether, this study provides a comprehensive analysis of self-organized body plan establishment in a minimal in vitro system of early mammalian patterning and highlights the regulative capacity of mESCs, thereby shedding light on underlying principles of axial polarity formation.

scholarly journals Self-Assembling Scaffolds Supported Long-Term Growth of Human Primed Embryonic Stem Cells and Upregulated Core and Naïve Pluripotent Markers

Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1650 ◽  
Author(s):  
Christina McKee ◽  
Christina Brown ◽  
G. Rasul Chaudhry
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Three Dimensional ◽  
Embryonic Stem ◽  
Extended Period ◽  
Culture Conditions ◽  
Differentiation Potential ◽  
Self Assembling

The maintenance and expansion of human embryonic stem cells (ESCs) in two-dimensional (2-D) culture is technically challenging, requiring routine manipulation and passaging. We developed three-dimensional (3-D) scaffolds to mimic the in vivo microenvironment for stem cell proliferation. The scaffolds were made of two 8-arm polyethylene glycol (PEG) polymers functionalized with thiol (PEG-8-SH) and acrylate (PEG-8-Acr) end groups, which self-assembled via a Michael addition reaction. When primed ESCs (H9 cells) were mixed with PEG polymers, they were encapsulated and grew for an extended period, while maintaining their viability, self-renewal, and differentiation potential both in vitro and in vivo. Three-dimensional (3-D) self-assembling scaffold-grown cells displayed an upregulation of core pluripotency genes, OCT4, NANOG, and SOX2. In addition, the expression of primed markers decreased, while the expression of naïve markers substantially increased. Interestingly, the expression of mechanosensitive genes, YAP and TAZ, was also upregulated. YAP inhibition by Verteporfin abrogated the increased expression of YAP/TAZ as well as core and naïve pluripotent markers. Evidently, the 3-D culture conditions induced the upregulation of makers associated with a naïve state of pluripotency in the primed cells. Overall, our 3-D culture system supported the expansion of a homogenous population of ESCs and should be helpful in advancing their use for cell therapy and regenerative medicine.

scholarly journals The ZT Biopolymer: A Self-Assembling Protein Scaffold for Stem Cell Applications

2019 ◽  
Vol 20 (17) ◽  
pp. 4299 ◽  
Author(s):  
Yevheniia Nesterenko ◽  
Christopher J. Hill ◽  
Jennifer R. Fleming ◽  
Patricia Murray ◽  
Olga Mayans
Keyword(s):  
Stem Cells ◽  
Self Assembly ◽  
Genetic Manipulation ◽  
Ex Vivo ◽  
Embryonic Stem ◽  
Building Blocks ◽  
Culture Conditions ◽  
Molecular Engineering ◽  
Induced Pluripotent

The development of cell culture systems for the naturalistic propagation, self-renewal and differentiation of cells ex vivo is a high goal of molecular engineering. Despite significant success in recent years, the high cost of up-scaling cultures, the need for xeno-free culture conditions, and the degree of mimicry of the natural extracellular matrix attainable in vitro using designer substrates continue to pose obstacles to the translation of cell-based technologies. In this regard, the ZT biopolymer is a protein-based, stable, scalable, and economical cell substrate of high promise. ZT is based on the naturally occurring assembly of two human proteins: titin-Z1Z2 and telethonin. These protein building blocks are robust scaffolds that can be conveniently functionalized with full-length proteins and bioactive peptidic motifs by genetic manipulation, prior to self-assembly. The polymer is, thereby, fully encodable. Functionalized versions of the ZT polymer have been shown to successfully sustain the long-term culturing of human embryonic stem cells (hESCs), human induced pluripotent stem cells (hiPSCs), and murine mesenchymal stromal cells (mMSCs). Pluripotency of hESCs and hiPSCs was retained for the longest period assayed (4 months). Results point to the large potential of the ZT system for the creation of a modular, pluri-functional biomaterial for cell-based applications.

scholarly journals Mesenchymal Stem Cells in the Treatment of COVID-19, a Promising Future

Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2588
Author(s):  
Daniela Gois Beghini ◽  
Samuel Iwao Horita ◽  
Andrea Henriques-Pons
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Intravenous Injection ◽  
Adult Stem Cells ◽  
Ethical Issues ◽  
Genetic Manipulation ◽  
Culture Media ◽  
Embryonic Stem

Mesenchymal stem cells (MSCs) are multipotent adult stem cells present in virtually all tissues; they have a potent self-renewal capacity and can differentiate into multiple cell types. They also affect the ambient tissue by the paracrine secretion of numerous factors in vivo, including the induction of other stem cells’ differentiation. In vitro, the culture media supernatant is named secretome and contains soluble molecules and extracellular vesicles that retain potent biological function in tissue regeneration. MSCs are considered safe for human treatment; their use does not involve ethical issues, as embryonic stem cells do not require genetic manipulation as induced pluripotent stem cells, and after intravenous injection, they are mainly found in the lugs. Therefore, these cells are currently being tested in various preclinical and clinical trials for several diseases, including COVID-19. Several affected COVID-19 patients develop induced acute respiratory distress syndrome (ARDS) associated with an uncontrolled inflammatory response. This condition causes extensive damage to the lungs and may leave serious post-COVID-19 sequelae. As the disease may cause systemic alterations, such as thromboembolism and compromised renal and cardiac function, the intravenous injection of MSCs may be a therapeutic alternative against multiple pathological manifestations. In this work, we reviewed the literature about MSCs biology, focusing on their function in pulmonary regeneration and their use in COVID-19 treatment.

scholarly journals Hypoxia-cultured human adipose-derived mesenchymal stem cells are non-oncogenic and have enhanced viability, motility, and tropism to brain cancer

2014 ◽  
Vol 5 (12) ◽  
pp. e1567-e1567 ◽  
Author(s):  
Y Feng ◽  
M Zhu ◽  
S Dangelmajer ◽  
Y M Lee ◽  
O Wijesekera ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Brain Cancer ◽  
Rapid Development ◽  
Embryonic Stem ◽  
Culture Conditions ◽  
Ambient Conditions ◽  
Tumor Initiating Cells

Abstract Adult human adipose-derived mesenchymal stem cells (hAMSCs) are multipotent cells, which are abundant, easily collected, and bypass the ethical concerns that plague embryonic stem cells. Their utility and accessibility have led to the rapid development of clinical investigations to explore their autologous and allogeneic cellular-based regenerative potential, tissue preservation capabilities, anti-inflammatory properties, and anticancer properties, among others. hAMSCs are typically cultured under ambient conditions with 21% oxygen. However, physiologically, hAMSCs exist in an environment of much lower oxygen tension. Furthermore, hAMSCs cultured in standard conditions have shown limited proliferative and migratory capabilities, as well as limited viability. This study investigated the effects hypoxic culture conditions have on primary intraoperatively derived hAMSCs. hAMSCs cultured under hypoxia (hAMSCs-H) remained multipotent, capable of differentiation into osteogenic, chondrogenic, and adipogenic lineages. In addition, hAMSCs-H grew faster and exhibited less cell death. Furthermore, hAMSCs-H had greater motility than normoxia-cultured hAMSCs and exhibited greater homing ability to glioblastoma (GBM) derived from brain tumor-initiating cells from our patients in vitro and in vivo. Importantly, hAMSCs-H did not transform into tumor-associated fibroblasts in vitro and were not tumorigenic in vivo. Rather, hAMSCs-H promoted the differentiation of brain cancer cells in vitro and in vivo. These findings suggest an alternative culturing technique that can enhance the function of hAMSCs, which may be necessary for their use in the treatment of various pathologies including stroke, myocardial infarction, amyotrophic lateral sclerosis, and GBM.

scholarly journals Expression Profile of New Marker Genes Involved in Differentiation of Canine Adipose-Derived Stem Cells into Osteoblasts

2021 ◽  
Vol 22 (13) ◽  
pp. 6663
Author(s):  
Maurycy Jankowski ◽  
Mariusz Kaczmarek ◽  
Grzegorz Wąsiatycz ◽  
Claudia Dompe ◽  
Paul Mozdziak ◽  
...  
Keyword(s):  
Stem Cells ◽  
In Vitro Culture ◽  
Osteogenic Differentiation ◽  
Molecular Mechanisms ◽  
Marker Genes ◽  
P Value ◽  
Illumina Platform

Next-generation sequencing (RNAseq) analysis of gene expression changes during the long-term in vitro culture and osteogenic differentiation of ASCs remains to be important, as the analysis provides important clues toward employing stem cells as a therapeutic intervention. In this study, the cells were isolated from adipose tissue obtained during routine surgical procedures and subjected to 14-day in vitro culture and differentiation. The mRNA transcript levels were evaluated using the Illumina platform, resulting in the detection of 19,856 gene transcripts. The most differentially expressed genes (fold change >|2|, adjusted p value < 0.05), between day 1, day 14 and differentiated cell cultures were extracted and subjected to bioinformatical analysis based on the R programming language. The results of this study provide molecular insight into the processes that occur during long-term in vitro culture and osteogenic differentiation of ASCs, allowing the re-evaluation of the roles of some genes in MSC progression towards a range of lineages. The results improve the knowledge of the molecular mechanisms associated with long-term in vitro culture and differentiation of ASCs, as well as providing a point of reference for potential in vivo and clinical studies regarding these cells’ application in regenerative medicine.

Abstract 129: Embryonic Stem Cell Derived Exosomes Revive Endogenous Repair Mechanisms In Failing Heart

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Mohsin Khan ◽  
Suresh K Verma ◽  
Alexander R Mackie ◽  
Erin Vaughan ◽  
Srikanth Garikipati ◽  
...  
Keyword(s):  
Stem Cells ◽  
Therapeutic Potential ◽  
Embryonic Stem ◽  
Cardiac Regeneration ◽  
Great Promise ◽  
Target Cells ◽  
Free System ◽  
Teratoma Formation

Rationale: Embryonic stem cells (ESCs) hold great promise for cardiac regeneration but are susceptible to ethical concerns, lack of autologous donors and teratoma formation. Recently, it has been observed that beneficial effects of stem cells are mediated by exosomes secreted out under various physiological conditions. ESCs have the ability to produce exosomes however their effect in the context of the heart is unknown. Objective: Determine the effect of ESC derived exosomes for cardiac repair and modulation of CPCs functions in the heart following myocardial infarction. Methods and Results: Exosomes were isolated from murine ESCs (mES Ex) or embryonic fibroblasts (MEFs) by ultracentrifugation and verified by Flotillin-1 immunoblot analysis. Induction of pluripotent markers, survival and in vitro tube formation was enhanced in target cells receiving ESC exosomes indicating therapeutic potential of mES Ex. mES Ex administration resulted in enhanced neovascularization, cardiomyocyte survival and reduced fibrosis post infarction consistent with resurgence of cardiac proliferative response. Importantly, mES Ex mediated considerable enhancement of cardiac progenitor cell (CPC) survival, proliferation and cardiac commitment concurrent with increased c-kit+ CPCs in vivo 4 weeks after mES Ex transfer. miRNA Array analysis of ESC and MEF exosomes revealed significantly high expression of miR290-295 cluster in the ESC exosomes compared to MEF exosomes. The underlying beneficial effect of mES Ex was tied to delivery of ESC miR-294 to the heart and in particular CPCs thereby promoting CPC survival and proliferation as analyzed by FACS based cell death analysis and CyQuant assay respectively. Interestingly, enhanced G1/S transition was observed in CPCs treated with miR-294 in conjunction with significant reduction of G1 phase. Conclusion: In conclusion, mES Ex provide a novel cell free system for cardiac regeneration with the ability to modulate both cardiomyocyte and CPC based repair programs in the heart thereby avoiding the risk of teratoma formation associated with ESCs.

Sign in / Sign up

Export Citation Format

Share Document