166 EXPRESSION OF PLURIPOTENCY-DETERMINING FACTORS IN IN VITRO-PRODUCED BUFFALO EMBRYOS

2008 ◽  
Vol 20 (1) ◽  
pp. 163
Author(s):  
T. Anand ◽  
D. Kumar ◽  
M. K. Singh ◽  
M. S. Chauhan ◽  
R. S. Manik ◽  
...  

Embryonic stem cells (ESCs) are derived from the inner cell mass (ICM) of blastocysts. These are pluripotent cells that retain the ability to differentiate into all cell types. Various cell surface antigens, the expressions of which have been widely used as markers to monitor the pluripotency of ESCs, include Oct-4, stage-specific embryonic antigens (SSEAs) such as SSEA-1, SSEA-3, and SSEA-4, and tumor rejection antigens (TRAs) such as TRA-1-60 and TRA-1-81. In this study, the cell surface expression patterns of these markers were examined in in vitro-produced buffalo embryos at the 2-, 4-, 8- to 16-cell, morula, and blastocyst stages using immunofluorescence microscopy. Oocytes obtained from slaughterhouse buffalo ovaries were subjected to IVM and IVF, following which the cleaved embryos were cultured for 9 days for production of embryos at different stages (n = 246). The embryos were fixed in 4% paraformaldehyde in Dulbecco's phosphate-buffered saline (DPBS) for 30 min, permeabilized by treatment with 0.1% Triton X-100 in DPBS for 30 min, and incubated first with the blocking solution (4% normal goat serum) for 30 min and then with the primary antibody (Oct-4: clone 9E3; SSEA-1: MC-480; SSEA-3: MC-631; SSEA-4: MC-813-70; TRA-1-60: clone TRA-1-60; and TRA-1-81: clone TRA-1-81, Chemicon� Inc., Temecula, CA, USA) at a dilution of 1:10 to 1:20 for 1 h. After being washed with DPBS, the embryos were incubated with appropriate FITC-labeled second antibody (anti-rat IgM or anti-mouse IgG or IgM, diluted 1:100 to 1:200) for 1 h and then examined under a fluorescence microscope. Oct-4 expression was detected at all embryonic stages starting from the 2-cell to the blastocyst stage, in which ICM, but not trophectoderm cells, exhibited a strong expression. SSEA-4 signal was found to be strongest at the 2-cell stage, with continued expression at all intermediate stages until the blastocyst stage in which there was a strong expression in ICM cells. In contrast, all of the embryonic stages were found to be negative for SSEA-3 expression. The SSEA-1 signal was present at all of the embryonic stages but was very weak. Expression of TRA-1-60 and TRA-1-81, which was detected only on the inner surface of the zona pellucida and in the perivitelline space in early embryonic stages, was absent in morulae and blastocysts. The results of this study indicate that the pluripotency-determining markers are differentially expressed in buffalo embryos and that the pattern of their expression is distinct from that of murine and human embryos but resembles to some extent that of goat embryos. Comparison of the expression pattern of these markers needs to be done between embryonic cells and ESCs for a better understanding of their developmental regulation.

Development ◽  
1989 ◽  
Vol 107 (3) ◽  
pp. 597-604 ◽  
Author(s):  
K. Hardy ◽  
A.H. Handyside ◽  
R.M. Winston

The development of 181 surplus human embryos, including both normally and abnormally fertilized, was observed from day 2 to day 5, 6 or 7 in vitro. 63/149 (42%) normally fertilized embryos reached the blastocyst stage on day 5 or 6. Total, trophectoderm (TE) and inner cell mass (ICM) cell numbers were analyzed by differential labelling of the nuclei with polynucleotide-specific fluorochromes. The TE nuclei were labelled with one fluorochrome during immunosurgical lysis, before fixing the embryo and labelling both sets of nuclei with a second fluorochrome (Handyside and Hunter, 1984, 1986). Newly expanded normally fertilized blastocysts on day 5 had a total of 58.3 +/− 8.1 cells, which increased to 84.4 +/− 5.7 and 125.5 +/− 19 on days 6 and 7, respectively. The numbers of TE cells were similar on days 5 and 6 (37.9 +/− 6.0 and 40.3 +/− 5.0, respectively) and then doubled on day 7 (80.6 +/− 15.2). In contrast, ICM cell numbers doubled between days 5 and 6 (20.4 +/− 4.0 and 41.9 +/− 5.0, respectively) and remained virtually unchanged on day 7 (45.6 +/− 10.2). There was widespread cell death in both the TE and ICM as evidenced by fragmenting nuclei, which increased substantially by day 7. These results are compared with the numbers of cells in morphologically abnormal blastocysts and blastocysts derived from abnormally fertilized embryos. The nuclei of arrested embryos were also examined. The number of TE and ICM cells allocated in normally fertilized blastocysts appears to be similar to the numbers allocated in the mouse. Unlike the mouse, however, the proportion of ICM cells remains higher, despite cell death in both lineages.


Reproduction ◽  
2020 ◽  
Vol 159 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Wei Cui ◽  
Agnes Cheong ◽  
Yongsheng Wang ◽  
Yuran Tsuchida ◽  
Yong Liu ◽  
...  

Microspherule protein 1 (MCRS1, also known as MSP58) is an evolutionarily conserved protein that has been implicated in various biological processes. Although a variety of functions have been attributed to MCRS1 in vitro, mammalian MCRS1 has not been studied in vivo. Here we report that MCRS1 is essential during early murine development. Mcrs1 mutant embryos exhibit normal morphology at the blastocyst stage but cannot be recovered at gastrulation, suggesting an implantation failure. Outgrowth (OG) assays reveal that mutant blastocysts do not form a typical inner cell mass (ICM) colony, the source of embryonic stem cells (ESCs). Surprisingly, cell death and histone H4 acetylation analysis reveal that apoptosis and global H4 acetylation are normal in mutant blastocysts. However, analysis of lineage specification reveals that while the trophoblast and primitive endoderm are properly specified, the epiblast lineage is compromised and exhibits a severe reduction in cell number. In summary, our study demonstrates the indispensable role of MCRS1 in epiblast development during early mammalian embryogenesis.


2009 ◽  
Vol 21 (9) ◽  
pp. 63
Author(s):  
L. Ganeshan ◽  
C. O'Neill

The developmental viability of the early embryo requires the formation of the inner cell mass (ICM) at the blastocyst stage. The ICM contributes to all cell lineages within the developing embryo in vivo and the embryonic stem cell (ESC) lineage in vitro. Commitment of cells to the ICM lineage and its pluripotency requires the expression of core transcription factors, including Nanog and Pou5f1 (Oct4). Embryos subjected to culture in vitro commonly display a reduced developmental potential. Much of this loss of viability is due to the up-regulation of TRP53 in affected embryos. This study investigated whether increased TRP53 disrupts the expression of the pluripotency proteins and the normal formation of the ICM lineage. Mouse C57BL6 morulae and blastocysts cultured from zygotes (modHTF media) possessed fewer (p < 0.001) NANOG-positive cells than equivalent stage embryos collected fresh from the uterus. Blocking TRP53 actions by either genetic deletion (Trp53–/–) or pharmacological inhibition (Pifithrin-α) reversed this loss of NANOG expression during culture. Zygote culture also resulted in a TRP53-dependent loss of POU5F1-positive cells from resulting blastocysts. Drug-induced expression of TRP53 (by Nutlin-3) also caused a reduction in formation of pluripotent ICM. The loss of NANOG- and POU5F1-positive cells caused a marked reduction in the capacity of blastocysts to form proliferating ICM after outgrowth, and a consequent reduced ability to form ESC lines. These poor outcomes were ameliorated by the absence of TRP53, resulting in transmission distortion in favour of Trp53–/– zygotes (p < 0.001). This study shows that stresses induced by culture caused TRP53-dependent loss of pluripotent cells from the early embryo. This is a cause of the relative loss of viability and developmental potential of cultured embryos. The preferential survival of Trp53–/– embryos after culture due to their improved formation of pluripotent cells creates a genetic danger associated with these technologies.


2010 ◽  
Vol 191 (1) ◽  
pp. 129-139 ◽  
Author(s):  
Daniel Mesnard ◽  
Daniel B. Constam

Axis formation and allocation of pluripotent progenitor cells to the germ layers are governed by the TGF-β–related Nodal precursor and its secreted proprotein convertases (PCs) Furin and Pace4. However, when and where Furin and Pace4 first become active have not been determined. To study the distribution of PCs, we developed a novel cell surface–targeted fluorescent biosensor (cell surface–linked indicator of proteolysis [CLIP]). Live imaging of CLIP in wild-type and Furin- and Pace4-deficient embryonic stem cells and embryos revealed that Furin and Pace4 are already active at the blastocyst stage in the inner cell mass and can cleave membrane-bound substrate both cell autonomously and nonautonomously. CLIP was also cleaved in the epiblast of implanted embryos, in part by a novel activity in the uterus that is independent of zygotic Furin and Pace4, suggesting a role for maternal PCs during embryonic development. The unprecedented sensitivity and spatial resolution of CLIP opens exciting new possibilities to elucidate PC functions in vivo.


2010 ◽  
Vol 22 (1) ◽  
pp. 350
Author(s):  
C. K. Lee ◽  
K. J. Uh ◽  
J. K. Park ◽  
H. S. Kim ◽  
H. M. Kim ◽  
...  

Porcine embryonic stem cells (ESC) can be a useful tool for the production of a transgenic animal and the study of developmental gene regulation. The study of porcine parthenogenetic ESC might also provide advantages in the understanding of changes in human parthenogenetic embryonic stem cells in the culture environment. Because human embryonic stem cells must be maintained stably for therapeutic uses, parthenogenetic porcine embryonic stem cells can give us precious information to help understand human parthenogenetic embryonic stem cells. Three putative porcine embryonic stem cell lines were derived from 99 parthenogenetic embryos. Cumulus-oocyte complexes were collected from prepubertal gilt ovaries and matured in vitro. Diploid parthenogenetic zygotes were produced by electrical activation followed by cytochalasin B treatment to suppress second polar body extrusion. Embryos were cultured to the blastocyst stage. Hatched blastocysts were directly cultured on mitomycin C-inactivated murine embryonic fibroblasts as feeder layers. Primary colonies were formed after 7 days of culture, and the colonies were transferred to new culture dishes 7 days after. They were passsaged every 5 days by physical dissociation, with one colony divided into small clumps and maintained for over 30 passages. These cells morphologically resembled human embryonic stem cells and consistently expressed the markers of pluripotent cells such as alkaline phosphatase, NANOG, OCT-4, SSEA-1, SSEA-4, TRA-1-60, and TRA-1-81. They could be maintained holding the previous characteristics after cryopreservation. Furthermore, we conducted experiments to confirm the expression patterns of the imprinted genes Igf2 and H19 in these ESC and IVF/parthenogenetic blastocysts using quantitative real-time PCR. At the blastocyst stage, the 2 genes were expressed in a parental-specific manner according to their origins in normal fertilized embryos and uniparental embryos. The putative parthenogenetic ESC, on the other hand, showed a high expression of Igf2, the paternally expressed gene, when compared with their blastocyst counterparts. Current work aims to confirm the authenticity of these ESC via teratoma formation in severe combined immunodeficiency mice following injection with these putative parthenogenetic ESC. This work was supported by the BioGreen 21 Program (#20070401034031, #20080401034031), Rural Development Administration, Republic of Korea (HK).


2006 ◽  
Vol 68 (1) ◽  
Author(s):  
Larry J. Pittman

Many Americans die each day from diseases affecting the heart, liver, kidneys, brain and a whole host of other bodily organs. Scientific researchers are constantly trying to develop new treatments for such medical conditions. Presently, the research community is working hard to develop medical treatments using stem cells from human embryos. That process involves extracting stem cells from either excess embryos that are no longer needed for in vitro fertilization or from embryos that are created through therapeutic cloning. At the blastocyst stage, about five days after the beginning of an embryo, researchers extract stem cells from the embryo and place them in a petri dish where the cells divide to produce a line of millions of stem cells. These stem cells are undifferentiated, meaning that they are still capable of transforming themselves into many different types of cells that exist in the human body. The hope is that physicians and other medical personnel will one day be able to inject these stem cells into a patient’s diseased heart, kidney, brain, liver, spinal cord or other organ, and the stem cells willtransform themselves into the same type of cells that comprise the host organ. The expectation is that the stem cells will repair the patient’s heart or other organs by curing diseases and otherwise improving the patient’s medical condition and life expectancy.


2005 ◽  
Vol 33 (6) ◽  
pp. 1526-1530 ◽  
Author(s):  
P.W. Andrews ◽  
M.M. Matin ◽  
A.R. Bahrami ◽  
I. Damjanov ◽  
P. Gokhale ◽  
...  

Embryonal carcinoma (EC) cells are the stem cells of teratocarcinomas, and the malignant counterparts of embryonic stem (ES) cells derived from the inner cell mass of blastocyst-stage embryos, whether human or mouse. On prolonged culture in vitro, human ES cells acquire karyotypic changes that are also seen in human EC cells. They also ‘adapt’, proliferating faster and becoming easier to maintain with time in culture. Furthermore, when cells from such an ‘adapted’ culture were inoculated into a SCID (severe combined immunodeficient) mouse, we obtained a teratocarcinoma containing histologically recognizable stem cells, which grew out when the tumour was explanted into culture and exhibited properties of the starting ES cells. In these features, the ‘adapted’ ES cells resembled malignant EC cells. The results suggest that ES cells may develop in culture in ways that mimic changes occurring in EC cells during tumour progression.


2021 ◽  
Author(s):  
Kilian Simmet ◽  
Mayuko Kurome ◽  
Valerie Zakhartchenko ◽  
Horst-Dieter Reichenbach ◽  
Claudia Springer ◽  
...  

The mammalian blastocyst undergoes two lineage segregations, i.e., formation of the trophectoderm and subsequently differentiation of the hypoblast (HB) from the inner cell mass, leaving the epiblast (EPI) the remaining pluripotent lineage. To clarify expression patterns of markers specific for these lineages in bovine embryos, we analyzed day 7, 9 and 12 blastocysts completely derived ex vivo by staining for OCT4, NANOG, SOX2 (EPI) and GATA6, SOX17 (HB) and identified genes specific for these developmental stages in a global transcriptomics approach. To study the role of OCT4, we generated OCT4-deficient (OCT4 KO) embryos via somatic cell nuclear transfer or in vitro fertilization. OCT4 KO embryos reached the expanded blastocyst stage by day 8 but lost of NANOG and SOX17 expression, while SOX2 and GATA6 were unaffected. Blastocysts transferred to recipient cows from day 6 to 9 expanded, but the OCT4 KO phenotype was not rescued by the uterine environment. Exposure of OCT4 KO embryos to exogenous FGF4 or chimeric complementation with OCT4 intact embryos did not restore NANOG or SOX17 in OCT4-deficient cells. Our data show, that OCT4 is required cell-autonomously for the maintenance of pluripotency of the EPI and differentiation of the HB in bovine embryos.


2009 ◽  
Vol 21 (1) ◽  
pp. 237
Author(s):  
H. M. Kim ◽  
J. K. Park ◽  
S. G. Lee ◽  
C. H. Park ◽  
S. W. Yoon ◽  
...  

The porcine embryonic stem (ES) cells could be a useful tool for the production of transgenic animals and the study of developmental gene regulation. Even though the efficiency of establishment of ES cells from in vivo blastocysts is relatively high, especially in mice, it is difficult and expensive to obtain in vivo embryos in domestic animals. Recent development of techniques in the production of embryos in vitro could be a useful source for the establishment of ES cells. However, the morphology and cell quality of in vitro-produced embryos are inferior to those of their in vivo counterparts. Although many attempts have been made to establish ES cells from in vitro-produced embryos, the overall efficiency is extremely low because of the poor embryo quality. However, aggregation of in vitro-produced embryos was developed to increase the number of cells in the inner cell mass (ICM) of blastocysts and could be useful in the application to ES cell establishment. Therefore, in this study, we attempted to derive porcine ES cells by using aggregation of in vitro-produced embryos by in vitro fertilization (IVF) or somatic cell nuclear transfer (SCNT). Cumulus–oocyte complexes were collected from prepubertal gilt ovaries and matured in vitro. Embryos at the 4-cell stage were produced by culturing embryos for 2 days after IVF and SCNT. After removal of the zona pellucida with acid Tyrode’s solution, three 4-cell-stage embryos (IVF3X) from IVF and two 4-cell-stage embryos (NT2X) from SCNT were aggregated by co-culturing them in an aggregation plate followed by culturing to the blastocyst stage. Embryos from IVF (IVF control) and SCNT (NT control) were also cultured to the blastocyst stage. All blastocysts were directly cultured on mitomycin C-inactivated murine embryonic fibroblasts as feeder layers. Two primary colonies were formed in the IVF control group (3.9%), whereas four primary colonies were formed in the IVF3X group (12.5%). One primary colony was formed in the NT2X group (20%), although no colony was formed in the NT control group. One of the IVF3X lines gradually disappeared after sub-passing, and the NT2X line also disappeared. Two ES-like cell lines derived from the IVF control were maintained up to 14 passages, and three ES-like lines from IVF3X were also maintained for more than 14 passages. These cells morphologically resembled human ES cells (flat and single layered) and expressed the markers of pluripotent cells such as alkaline phosphatase, NANOG, Oct-4, SSEA-1, SSEA-4, TRA-1-60, and TRA-1-81. These results indicated that a porcine ES cell line could be established from in vitro-produced aggregated blastocysts. Further research is required to establish ES cell lines from SCNT embryos and characterize the differentiation and developmental abilities of these porcine ES-like cells. This work was supported by the BioGreen 21 Program (#20070401034031, #20080401034031), Rural Development Administration, Republic of Korea (HK).


2019 ◽  
Vol 25 (7) ◽  
pp. 397-407
Author(s):  
Yvonne Wilson ◽  
Ian D Morris ◽  
Susan J Kimber ◽  
Daniel R Brison

Abstract Apoptosis occurs primarily in the blastocyst inner cell mass, cells of which go on to form the foetus. Apoptosis is likely to play a role in ensuring the genetic integrity of the foetus, yet little is known about its regulation. In this study, the role of the mouse gene, transformation-related protein 53 (Trp53) in the response of embryos to in vitro culture and environmentally induced DNA damage was investigated using embryos from a Trp53 knockout mouse model. In vivo-derived blastocysts were compared to control embryos X-irradiated at the two-cell stage and cultured to Day 5. An analysis of DNA by comet assay demonstrated that 1.5 Gy X-irradiation directly induced damage in cultured two-cell mouse embryos; this was correlated with retarded development to blastocyst stage and increased apoptosis at the blastocyst stage but not prior to this. Trp53 null embryos developed to blastocysts at a higher frequency and with higher cell numbers than wild-type embryos. Trp53 also mediates apoptosis in conditions of low levels of DNA damage, in vivo or in vitro in the absence of irradiation. However, following DNA damage induced by X-irradiation, apoptosis is induced by Trp53 independent as well as dependent mechanisms. These data suggest that Trp53 and apoptosis play important roles in normal mouse embryonic development both in vitro and in vivo and in response to DNA damage. Therefore, clinical ART practices that alter apoptosis in human embryos and/or select embryos for transfer, which potentially lack a functional Trp53 gene, need to be carefully considered.


Sign in / Sign up

Export Citation Format

Share Document