223 GENERATION OF INTERSPECIES CHIMERAS BETWEEN PRIMATE INDUCED PLURIPOTENT STEM CELLS AND PORCINE PARTHENOGENETIC EMBRYOS

2016 ◽  
Vol 28 (2) ◽  
pp. 243
Author(s):  
M. Nowak-Imialek ◽  
S. Wunderlich ◽  
D. Herrmann ◽  
S. Klein ◽  
U. Baulain ◽  
...  

The availability of human induced pluripotent stem cell (hiPSC) paves the way to generate regenerative tissue or organs from patient’s own stem cells. The production of chimeric piglets carrying organs that are entirely derived from human stem cells, or at least have a high contribution of human cells or tissues, could be used as a new tissue or an organ replacement in the future treatment of the patients. Here, we produced porcine-nonhuman primate chimeric embryos to assess the feasibility of the potential use of human iPSC for production of human stem cell-derived organs in pigs. Because in vitro culture conditions for cynomolgus monkey iPSC and porcine blastocysts are different, we first identified an effective in vitro culture system for porcine blastocysts and monkey iPSC. We compared blastocyst rates (Days 7 and 8) and number of cells of porcine parthenogenetic blastocysts (Day 8) cultured in 8 different monkey iPSC media and in porcine zygote medium 3 (PZM-3). The best developmental rates of porcine blastocysts were achieved in Knockout DMEM+20% serum replacement monkey medium (iPS 20% medium; N = 65, n = 3). The number of blastocysts on Day 8 cultured in iPS 20% medium was significantly higher (91%; P < 0.05) than in the commonly used porcine PZM-3 medium (65%). We found significantly fewer (P < 0.05) degenerate porcine embryos on Day 8 after culture in iPS 20% medium (9%) compared to PZM-3 (35%). The number of nuclei per blastocyst in iPS 20% medium (88 nuclei; N = 30, n = 3) was significantly higher (P < 0.0001) than in the PZM-3 medium (57 nuclei; N = 54, n = 3). Therefore, we decided to use iPS 20% medium for culture of porcine blastocysts injected with monkey iPSC. Thereafter, we injected clusters of 10 to 15 monkey iPSC transgenic with AAVS1-CAG-Venus into porcine parthenogenetic embryos from Days 4 and 6. Interspecies chimeras were cultured in iPS 20% medium for 24 (for Day 6 embryos) or 48 h (for Day 4 embryos) and observed by confocal microscopy to determine the proportion of Venus-expressing monkey iPSC in porcine embryos. Approximately 37% of blastocysts contained Venus-positive cells after injection of Day 6 embryos (N = 133, n = 4). In contrast, injection into porcine embryos from Day 4 resulted in 73% of Venus-positive blastocysts (N = 69, n = 3). Finally, we investigated proliferation and survival of monkey iPSC in interspecies chimeras after blastocyst plating onto murine fibroblasts. Chimeric blastocyst outgrowth resulted in Venus-expressing monkey iPSC proliferating over 1 week in culture. Outgrowths of all chimeric blastocysts established distinct but separate monkey and porcine stem cell colonies. Here, we optimized the culture conditions for an in vitro interspecies chimera assay in which monkey iPSC are able to survive in porcine embryos. Integration of monkey iPSC to host inner cell mass is relevant for the further contribution to the embryo development. Therefore, to verify this, analysis of cell-cell connection between monkey iPSC and porcine blastocysts and experiments using vivo-derived embryos are currently underway.

2010 ◽  
Vol 22 (1) ◽  
pp. 354
Author(s):  
T. S. Rascado ◽  
J. F. Lima-Neto ◽  
S. E. R. S. Lorena ◽  
B. W. Minto ◽  
F. C. Landim-Alvarenga

The domestic cat can be used as a biological model for humans because of similarities in some disease and genetically transmitted conditions. Embryonic stem cells might complete nuclear reprogramming more efficiently than somatic cells and, therefore, are potentially useful for increasing interspecific cloning success. The objective of this study was to establish an effective culture system for inner cell mass (ICM)-derived cells in the domestic cat, testing the ability of the ICM to attach to the culture dish and to form embryonic stem cell colonies in the presence of fetal calf serum (FCS) and Knockout serum (KS). Moreover, knowing that the transcription factor Oct-4 is important for the maintenance of pluripotency in human and murine embryonic stem cells, the expression of this factor was evaluated in in vitro-produced blastocyst and in the attached ICM. Domestic cat oocytes were matured, fertilized, and cultured in vitro until the blastocyst stage. The ICM was mechanically isolated (n = 60) using a scalpel blade and transferred to a monolayer of chemically inactivated cat fibroblasts with 10 μg mL-1 mitomicin C. The base culture media (BM) was DMEM/F12 supplemented with nonessential amino acids, glutamine, leukemia inhibitory factor, fibroblast growth factor-2, 2-mercaptoethanol, and antibiotics. Three groups were tested: G1 = BM with 20% FCS (20); G2 = BM with 20% KS (20); G3 = BM with 15% FSC and 5% KS (20). Culture was performed in a 5% CO2 in air incubator at 38.5°C. No statistical difference was observed among groups in relation to ICM attachment (chi-square, P > 0.05). Ninety percent of the ICM presented good adhesion after 3 days of culture and started to grow in all media tested. However, until now, no good colonies were formed. Fifteen blastocysts and 10 attached ICM were fixed in 3% paraformaldehyde and permeabilized in 0.2% triton X-100 in PBS. Subsequently, to block nonspecific binding of the primary antibody, the preadsorption for 2 h at room temperature with OCT4 blocking peptide (sc-8628P, Santa Cruz Biotechnology, Santa Cruz, CA, USA) was used. Samples were incubated with Oct4 antibody (N-19 : sc 8628, Santa Cruz Biotechnology) and with the appropriate secondary antibody (A21431, Invitrogen) and examined by fluorescence microscopy. Oct4 protein was detected both in the ICM and trophoderm cells, and it was distributed in cytoplasm and nuclei. These embryos were also stained with Hoechst 33342. Although further standardization of the culture media is needed, it seems that the KS can be replaced by FCS in cat embryonic stem cell culture. Furthermore, the immunostain of the trophoderm with Oct-4 indicates a difference in the expression of this factor when compared with its expression on human and murine blastocysts. This could be related to in vitro production, or Oct 4 is not a good pluripotency marker for cat embryos and cat embryonic stem cell, consequently. This fact has been noted in goat, bovine, and porcine embryos. Acknowledgment is given to FAPESP.


2011 ◽  
Vol 23 (1) ◽  
pp. 249
Author(s):  
D. Kumar ◽  
D. Malakar ◽  
R. Dutta ◽  
S. Garg ◽  
S. Sahu ◽  
...  

Embryonic stem cells (ESC) are derived from the inner cell mass of blastocysts and proliferate extensively while maintaining pluripotency. They can be used for the treatment of juvenile diabetes, Parkinson’s disease, heart failure, and spinal cord injury. However, the use of embryos and tissue rejection remain concerns for ESC transplantation. Reprogramming of somatic cells may be done by different methods such as somatic cell nuclear transfer (Wilmut et al. 1997), fusion of somatic cells (Cowen et al. 2005), treatment with the extract of the pluripotent stem cells (Johnson Rajasingh 2008), and by the stable ectopic expression of defined factors in the somatic cells (Takahashi and Yamanaka 2006). Several transcription factors, including Oct3/4 (Nichols et al. 1998; Niwa et al. 2000), Sox2 (Avilion et al. 2003), and Nanog (Chambers et al. 2003; Mitsui et al. 2003), function in the maintenance of pluripotency in both early embryos and ESC. Takahashi and Yamanaka reported reprogramming the fibroblast cells into stem cells by introducing Oct3/4, Sox2, c-Myc, and Klf4 in mouse embryonic and adult fibroblasts. Yu et al. (2007) demonstrated that four transcription factors (OCT-4, SOX2, NANOG, and LIN28) are sufficient to reprogramme human somatic cells to pluripotent stem cells that exhibit the essential characteristics of ESC. Nakagawa et al. (2008) used three factors (OCT3/4, SOX2, and KLF4) for human iPS cell production from somatic cells. We are trying to reprogramme the adult goat fibroblast cells in induced pluripotent stem cells by using ectopic expression of transcription factors such as Oct-4, Sox2, Nanog, and Lin28. We collected the ovaries from a slaughtered animal from Delhi and collected the oocytes from ovaries. Then after the collection, A and B grade oocytes were selected. Selected oocytes were processed and incubated in in vitro maturation media for 24 h. We collected semen from a male goat, and it was processed and capacitated in sperm TALP. Capacitated sperms were used for IVF of the in vitro matured oocytes in ferTALP. After 12 h sperm were washed from oocytes in embryo developing media (EDM), and oocytes were cultured (in vitro) in EDM. After 24 h cleavage occurred. The cleaved embryos were cultured for 6 to 7 days. At the 7th day, we got blastocysts. From these blastocysts, inner cell mass was isolated enzymatically and cultured to get ESC. The ESC were cultured for 7 passages and used for RNA isolation. The RNA was isolated from these stem cells by the Trizol method. Complementary DNA was prepared by RT-PCR. Using gene-specific primer for Oct-4, Nanog, and Sox2, DNA was amplified. The DNA for the Oct-4, Nanog, and Sox2 genes was cloned in pJET cloning vector and transformed in Top10 E. coli competence cells. After screening, plasmid was isolated and sent for sequencing. Sequences were analysed and the complete open reading frame was created for Oct-4, Nanog, and Sox2.


2017 ◽  
Vol 4 (S) ◽  
pp. 147
Author(s):  
Ho Thi-Kim Ngan ◽  
Nguyen Van Thuan ◽  
Hong-Thuy Bui

Parthenogenesis is a process in which zygotes are produced without sperm presence. Due to lack of paternal genes, parthenogenetic embryos cannot develop to full-term; however, these embryos show a great potential to generate histocompatible stem cells (parthenogenetic embryonic stem – pES cells) for transplantation. In this research, parthenogenetic activation in the mouse was carried out using strontium chloride (SrCl2) combined with cytochalasin B (CB). The rate of embryo development, blastocyst quality and expression of acetylation of histone H4 lysine 12 (H4K12Ac) were investigated, while parthenogenetic blastocysts were used to establish pES cells. The results showed that rate of in vitro blastulation of parthenogenetic embryos was lower than that of fertilized ones (45.1% vs 98.0%, respectively). In addition, blastocysts developed from parthenogenetic embryos also expressed lower quality, which was demonstrated by lower total cell number. Moreover, H4K12Ac expression significantly decreased in the inner cell mass (ICM) of parthenogenetic blastocysts compared to fertilized ones, indicating a possible reason for lower blastocyst quality. Following embryo collection and activation, two ES cell lines – fertilized (fES) and pES cell lines have been successfully established and maintained long term in vitro. To sum up, differences in blastocyst quality and H4K12Ac expression in ICM cells of blastocyst may contribute to aberrant developmental and embryonic stem cell formation in parthenogenetic embryos.


2020 ◽  
Author(s):  
Mohammad Jaber ◽  
Ahmed Radwan ◽  
Netanel Loyfer ◽  
Mufeed Abdeen ◽  
Shulamit Sebban ◽  
...  

Following fertilization, totipotent cells divide to generate two compartments in the early embryo: the inner cell mass (ICM) and trophectoderm (TE). It is only at the 32-64 -cell stage when a clear segregation between the two cell-types is observed, suggesting a ‘T’-shaped model of specification. Here, we examine whether the acquisition of these two states in vitro by nuclear reprogramming share similar dynamics/trajectories. We conducted a comparative parallel multi-omics analysis on cells undergoing reprogramming to Induced pluripotent stem cells (iPSCs) and induced trophoblast stem cells (TSCs), and examined their transcriptome, methylome, chromatin accessibility and activity and genomic stability. Our analysis revealed that cells undergoing reprogramming to pluripotency and TSC state exhibit specific trajectories from the onset of the process, suggesting ‘V’-shaped model. Using these analyses, not only we could describe in detail the various trajectories toward the two states, we also identified previously unknown stage-specific reprogramming markers as well as markers for faithful reprogramming and reprogramming blockers. Finally, we show that while the acquisition of the TSC state involves the silencing of embryonic programs by DNA methylation, during the acquisition of pluripotency these specific regions are initially open but then retain inactive by the elimination of the histone mark, H3K27ac.


2014 ◽  
Vol 4 (1) ◽  
Author(s):  
Jin Young Joo ◽  
Hyun Woo Choi ◽  
Min Jung Kim ◽  
Holm Zaehres ◽  
Natalia Tapia ◽  
...  

Abstract Several mouse pluripotent stem cell types have been established either from mouse blastocysts and epiblasts. Among these, embryonic stem cells (ESCs) are considered to represent a “naïve”, epiblast stem cells (EpiSCs) a “primed” pluripotent state. Although EpiSCs form derivatives of all three germ layers during in vitro differentiation, they rarely incorporate into the inner cell mass of blastocysts and rarely contribute to chimera formation following blastocyst injection. Here we successfully established homogeneous population of EpiSC lines with efficient chimera-forming capability using a medium containing fibroblast growth factor (FGF)-4. The expression levels of Rex1 and Nanog was very low although Oct4 level is comparable to ESCs. EpiSCs also expressed higher levels of epiblast markers, such as Cer1, Eomes, Fgf5, Sox17 and T, and further showed complete DNA methylation of Stella and Dppa5 promoters. However, the EpiSCs were clustered separately from E3 and T9 EpiSC lines and showed a completely different global gene expression pattern to ESCs. Furthermore, the EpiSCs were able to differentiate into all three germ layers in vitro and efficiently formed teratomas and chimeric embryos (21.4%) without germ-line contribution.


2021 ◽  
Vol 22 (9) ◽  
pp. 5011
Author(s):  
Daehwan Kim ◽  
Sangho Roh

Stem cell research is essential not only for the research and treatment of human diseases, but also for the genetic preservation and improvement of animals. Since embryonic stem cells (ESCs) were established in mice, substantial efforts have been made to establish true ESCs in many species. Although various culture conditions were used to establish ESCs in cattle, the capturing of true bovine ESCs (bESCs) has not been achieved. In this review, the difficulty of establishing bESCs with various culture conditions is described, and the characteristics of proprietary induced pluripotent stem cells and extended pluripotent stem cells are introduced. We conclude with a suggestion of a strategy for establishing true bESCs.


2019 ◽  
Vol 55 (7) ◽  
pp. 473-481 ◽  
Author(s):  
Ali Cihan Taskin ◽  
Ahmet Kocabay ◽  
Ayyub Ebrahimi ◽  
Sercin Karahuseyinoglu ◽  
Gizem Nur Sahin ◽  
...  

2010 ◽  
Vol 88 (3) ◽  
pp. 479-490 ◽  
Author(s):  
Guoliang Meng ◽  
Shiying Liu ◽  
Xiangyun Li ◽  
Roman Krawetz ◽  
Derrick E. Rancourt

Embryonic stem cells (ESCs) are derived from the inner cell mass (ICM) of the blastocyst. Because of their ability to differentiate into a variety of cell types, human embryonic stem cells (hESCs) provide an unlimited source of cells for clinical medicine and have begun to be used in clinical trials. Presently, although several hundred hESC lines are available in the word, only few have been widely used in basic and applied research. More and more hESC lines with differing genetic backgrounds are required for establishing a bank of hESCs. Here, we report the first Canadian hESC lines to be generated from cryopreserved embryos and we discuss how we navigated through the Canadian regulatory process. The cryopreserved human zygotes used in this study were cultured to the blastocyst stage, and used to isolate ICM via microsurgery. Unlike previous microsurgery methods, which use specialized glass or steel needles, our method conveniently uses syringe needles for the isolation of ICM and subsequent hESC lines. ICM were cultured on MEF feeders in medium containing FBS or serum replacer (SR). Resulting outgrowths were isolated, cut into several cell clumps, and transferred onto fresh feeders. After more than 30 passages, the two hESC lines established using this method exhibited normal morphology, karyotype, and growth rate. Moreover, they stained positively for a variety of pluripotency markers and could be differentiated both in vitro and in vivo. Both cell lines could be maintained under a variety of culture conditions, including xeno-free conditions we have previously described. We suggest that this microsurgical approach may be conducive to deriving xeno-free hESC lines when outgrown on xeno-free human foreskin fibroblast feeders.


Sign in / Sign up

Export Citation Format

Share Document