Inhibition of trophoblast stem cell potential in chorionic ectoderm coincides with occlusion of the ectoplacental cavity in the mouse

At the blastocyst stage of pre-implantation mouse development, close contact of polar trophectoderm with the inner cell mass (ICM) promotes proliferation of undifferentiated diploid trophoblast. However, ICM/polar trophectoderm intimacy is not maintained during post-implantation development, raising the question of how growth of undifferentiated trophoblast is controlled during this time. The search for the cellular basis of trophoblast proliferation in post-implantation development was addressed with an in vitro spatial and temporal analysis of fibroblast growth factor 4-dependent trophoblast stem cell potential. Two post-implantation derivatives of the polar trophectoderm – early-streak extra-embryonic ectoderm and late-streak chorionic ectoderm – were microdissected into fractions along their proximodistal axis and thoroughly dissociated for trophoblast stem cell culture. Results indicated that cells with trophoblast stem cell potential were distributed throughout the extra-embryonic/chorionic ectoderm, an observation that is probably attributable to non-coherent growth patterns exhibited by single extra-embryonic ectoderm cells at the onset of gastrulation. Furthermore, the frequency of cells with trophoblast stem cell potential increased steadily in extra-embryonic/chorionic ectoderm until the first somite pairs formed, decreasing thereafter in a manner independent of proximity to the allantois. Coincident with occlusion of the ectoplacental cavity via union between chorionic ectoderm and the ectoplacental cone, a decline in the frequency of mitotic chorionic ectoderm cells in vivo, and of trophoblast stem cell potential in vitro, was observed. These findings suggest that the ectoplacental cavity may participate in maintaining proliferation throughout the developing chorionic ectoderm and, thus, in supporting its stem cell potential. Together with previous observations, we discuss the possibility that fluid-filled cavities may play a general role in the development of tissues that border them.

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Faculty Opinions recommendation of Inhibition of trophoblast stem cell potential in chorionic ectoderm coincides with occlusion of the ectoplacental cavity in the mouse.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1009601.130807 ◽

2002 ◽

Author(s):

Patrick Tam

Keyword(s):

Stem Cell ◽

Cell Potential ◽

Trophoblast Stem ◽

Trophoblast Stem Cell ◽

Stem Cell Potential

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Impact of Galectin-1 on Trophoblast Stem Cell Differentiation and Invasion in In Vitro Implantation Model

Reproductive Sciences ◽

10.1177/1933719117725816 ◽

2017 ◽

Vol 25 (5) ◽

pp. 700-711 ◽

Cited By ~ 2

Author(s):

Minyue Tang ◽

Jiali You ◽

Wei Wang ◽

Yongchao Lu ◽

Xiaoling Hu ◽

...

Keyword(s):

Stem Cell ◽

Cell Differentiation ◽

Stem Cell Differentiation ◽

Trophoblast Stem ◽

Trophoblast Stem Cell ◽

Implantation Model

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Multipotential ability of primitive germ cells from neonatal pig testis cultured in vitro

Reproduction Fertility and Development ◽

10.1071/rd08176 ◽

2009 ◽

Vol 21 (5) ◽

pp. 696 ◽

Cited By ~ 19

Author(s):

Sandeep Goel ◽

Mayako Fujihara ◽

Kazuo Tsuchiya ◽

Yuji Takagi ◽

Naojiro Minami ◽

...

Keyword(s):

Stem Cell ◽

Transcription Factors ◽

Germ Cells ◽

Cultured Cells ◽

Primordial Germ Cells ◽

Primary Cultures ◽

Cell Potential ◽

Neonatal Pig ◽

Stem Cell Potential

Gonocytes are progenitor-type germ cells that arise from primordial germ cells and differentiate further into spermatogonia, thereby initiating spermatogenesis. In the present study, freshly isolated gonocytes were found to have either weak or no expression of pluripotency determining transcription factors, such as POU5F1, SOX2 and C-MYC. Interestingly, the expression of these transcription factors, as well as other vital transcription factors, such as NANOG, KLF4 and DAZL, were markedly upregulated in cultured cells. Cells in primary cultures expressed specific germ cell and pluripotency markers, such as lectin Dolichos biflorus agglutinin (DBA), KIT, ZBTB16, stage-specific embryonic antigen (SSEA-1), NANOG and POU5F1. Using a monoclonal antibody to specifically identify porcine germ cells, the stem cell potential of fresh and cultured cells was determined with a testis xenotransplantation assay. Colonised porcine germ cells were detected only in mouse testes that were either transplanted with fresh testicular cells or with cells from primary cultures. Interestingly, testes transplanted with cells from primary cultures showed colonisation of germ cells in the interstitial space, reflecting their tumourigenic nature. The formation of teratomas with tissues originating from the three germinal layers following the subcutaneous injection of cells into nude mice from primary cultures confirmed their multipotency. The results of the present study may provide useful information for the establishment of multipotent germ stem cell lines from neonatal pig testis.

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Quantitative and qualitative in vitro analysis of the stem cell potential of hematopoietic cells purified from murine skeletal muscle

Cell Research ◽

10.1038/cr.2007.74 ◽

2007 ◽

Vol 17 (9) ◽

pp. 783-791 ◽

Cited By ~ 4

Author(s):

Celine Haond ◽

Françoise Farace ◽

Martine Guillier ◽

Yann Lécluse ◽

Frederic Mazurier ◽

...

Keyword(s):

Skeletal Muscle ◽

Stem Cell ◽

Hematopoietic Cells ◽

Cell Potential ◽

Murine Skeletal Muscle ◽

Stem Cell Potential ◽

Vitro Analysis ◽

In Vitro Analysis

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Targeting Chronic Myeloid Leukemia Stem Cells through Pharmacological Inhibition of HIF-1α

Blood ◽

10.1182/blood.v128.22.4235.4235 ◽

2016 ◽

Vol 128 (22) ◽

pp. 4235-4235

Author(s):

Giulia Cheloni ◽

Michele Tanturli ◽

DeSouza Ho Ngoc ◽

Yi Shan ◽

Ignazia Tusa ◽

...

Keyword(s):

Stem Cell ◽

Myeloid Leukemia ◽

Low Oxygen ◽

Cell Potential ◽

Viable Cells ◽

Stem Cell Potential ◽

Formation Efficiency ◽

Colony Formation Efficiency

Abstract Chronic myeloid leukemia (CML) is a clonal hematopoietic stem cell (HSC) disorder due to the 9;22(q34.1;q11.2) reciprocal chromosomal translocation, which results in the generation of BCR/abl "fusion" oncogene and the expression of the BCR/Abl oncoprotein, a constitutively-active tyrosine kinase (TK). To date, chronic-phase CML patients are treated with TK inhibitors (TKi) such as imatinib- mesylate (IM) and dasatinib. However, to eradicate CML, it is necessary to eliminate Leukemia Stem Cells (LSC), which are largely insensitive to TKi. Thus, TKi, rather than curing CML definitively, induce a state of minimal residual disease (MRD) apparently sustained by LSC persistence. Therefore, the identification of non-TKi drugs capable to target and eradicate LSC responsible for MRD and therefore the risk of relapse of disease is of primary importance. LSC, as well as normal HSC, in vivo reside in low oxygen tension areas of the bone marrow (BM) called "HSC niche". Several previous studies from our group and others demonstrate that low oxygen tension maintains the survival and stem cell potential of HSC and LSC, favoring their self-renewal. Interestingly, we also found that the expression of BCR/Abl oncoprotein is suppressed in low oxygen, which well explains the refractoriness of LSC to TKi, provided they manage to survive in the absence of BCR/Abl signaling. Hypoxia-Inducible Factor-1α (HIF-1α) is a key regulator of cell adaptation to low oxygen and of LSC maintenance. This study addresses the in vitro and in vivo effects of the pharmacological inhibition of HIF-1α on the maintenance of CML stem cell potential. After screening several HIF-1α inhibitors, we found that Acriflavine (ACF) induced apoptosis and DNA damage in CML cells and identified ACF as a very effective inhibitor of CML cell survival and growth in low oxygen, as regards the number of viable cells in culture and colony formation efficiency of CML cell lines or human or murine primary cells. Interestingly, ACF did not affect the colony formation efficiency of normal human hematopoietic cells. We also demonstrated in this study that IM and ACF exhibited an at least additive effect as far as the reduction of the total number of viable cells in low oxygen is concerned. Moreover, we demonstrated that low-oxygen incubation of CML cells increased the expression of genes related to stem cell potential, such as Nanog, Sox2 and Oct4, and that ACF treatment reduced their expression. These results on one hand confirmed that hypoxia selects cells with SC potential, on the other hand they demonstrated that ACF treatment reduces their maintenance. Moreover, we evaluated the maintenance of CML stem cell potential using a stem cell assay, demonstrating that ACF suppressed the stem cell potential of CML cell lines or primary cells. On the contrary, IM or Dasatinib, were unable to affect the stem cell potential of CML cells also when administered to primary samples neither TKi-treated before nor carrying primary mutations of BCR/Abl kinase domain. This is in agreement with what observed before by us and others and confirms the refractoriness of LSC to TKi. The effects of ACF in vivo were evaluated using a murine CML model where the disease was induced by a BCR/abl-carrying retrovirus. A 10 day-long ACF treatment was sufficient to attenuate CML development in mice, as evidenced by lower spleen weight, fewer leukemia cells in peripheral blood and BM, and a markedly reduced leukemia cell infiltration into the lungs. Moreover, it was possible to confirm in vivo the effects of ACF on LSC observed in vitro. ACF treatment indeed reduced the maintenance of the Long-Term LSC-containing LSK cell subset (CD34- LSK) in the BM of CML mice. Interestingly and in keeping with the less-severe addiction of HSC to HIF-1α deficiency, we found that non-CML cells were significantly less sensitive to ACF treatment than CML cells. This points to a good therapeutic index of ACF in discriminating leukemic from normal hematopoietic cells. On the basis of all above, the ACF/TKi combination may represent a novel therapeutic approach to target at one time CML cell bulk and LSC, in order to induce remission and prevent MRD of CML. Interestingly, ACF is an already FDA-approved drug for non-oncological uses in humans. Disclosures No relevant conflicts of interest to declare.

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