scholarly journals Reprogrammed Pteropus Bat Stem Cells Present Distinct Immune Signature and are Highly Permissive for Henipaviruses

2019 ◽  
Author(s):  
Noémie Aurine ◽  
Camille Baquerre ◽  
Maria Gaudino ◽  
Christian Jean ◽  
Claire Dumont ◽  
...  

AbstractBats are unique among mammals due to the ability of powered flight and exceptional longevity. They are also asymptomatic hosts for numerous viruses, including recently emerged zoonotic Henipaviruses Nipah and Hendra, which are highly pathogenic for humans and other mammals. Better understanding of how bats control viral infection requires development of relevant permissive cellular experimental models. By applying a somatic reprogramming protocol to Pteropus bat primary cells, using a novel combination of ESRRB, CDX2, and c-MYC transcription factors, we generated bat reprogrammed cells exhibiting stem cell-like characteristics and a neural stem cell-like molecular signature. These cells present a unique interferon-stimulated transcriptomic signature and both produce and respond to interferon type-I, highlighting differences between stem cells from bats and other mammals. In contrast to primary bat cells, these reprogrammed cells are highly susceptible to infection by Henipavirus, thereby enabling isolation of new bat viruses, study of virus-bat interactions, and better understanding of bat biology.Summary sentenceSomatic reprogramming provides new bat stem cells with unique immune properties and original viral permissivness

2021 ◽  
Vol 9 (12) ◽  
pp. 2567
Author(s):  
Noémie Aurine ◽  
Camille Baquerre ◽  
Maria Gaudino ◽  
Christian Jean ◽  
Claire Dumont ◽  
...  

Bats are natural hosts for numerous zoonotic viruses, including henipaviruses, which are highly pathogenic for humans, livestock, and other mammals but do not induce clinical disease in bats. Pteropus bats are identified as a reservoir of henipaviruses and the source of transmission of the infection to humans over the past 20 years. A better understanding of the molecular and cellular mechanisms allowing bats to control viral infections requires the development of relevant, stable, and permissive cellular experimental models. By applying a somatic reprogramming protocol to Pteropus bat primary cells, using a combination of ESRRB (Estrogen Related Receptor Beta), CDX2 (Caudal type Homeobox 2), and c-MYC (MYC proto-oncogene) transcription factors, we generated bat reprogrammed cells. These cells exhibit stem cell-like characteristics and neural stem cell molecular signature. In contrast to primary fibroblastic cells, these reprogrammed stem cells are highly permissive to henipaviruses and exhibit specific transcriptomic profiles with the particular expression of certain susceptibility factors such as interferon-stimulated genes (ISG), which may be related to viral infection. These Pteropus bat reprogrammed stem cells should represent an important experimental tool to decipher interactions during henipaviruses infection in Pteropus bats, facilitate isolation and production of bat-borne viruses, and to better understand the bat biology.


2019 ◽  
Vol 14 (2) ◽  
pp. 146-151 ◽  
Author(s):  
Junaid Khan ◽  
Amit Alexander ◽  
Mukta Agrawal ◽  
Ajazuddin ◽  
Sunil Kumar Dubey ◽  
...  

Diabetes and its complications are a significant health concern throughout the globe. There are physiological differences in the mechanism of type-I and type-II diabetes and the conventional drug therapy as well as insulin administration seem to be insufficient to address the problem at large successfully. Hypoglycemic swings, frequent dose adjustments and resistance to the drug are major problems associated with drug therapy. Cellular approaches through stem cell based therapeutic interventions offer a promising solution to the problem. The need for pancreatic transplants in case of Type- I diabetes can also be by-passed/reduced due to the formation of insulin producing β cells via stem cells. Embryonic Stem Cells (ESCs) and induced Pluripotent Stem Cells (iPSCs), successfully used for generating insulin producing β cells. Although many experiments have shown promising results with stem cells in vitro, their clinical testing still needs more exploration. The review attempts to bring into light the clinical studies favoring the transplantation of stem cells in diabetic patients with an objective of improving insulin secretion and improving degeneration of different tissues in response to diabetes. It also focuses on the problems associated with successful implementation of the technique and possible directions for future research.


2021 ◽  
Vol 12 (6) ◽  
Author(s):  
Manuel Pedro Jimenez-García ◽  
Antonio Lucena-Cacace ◽  
Daniel Otero-Albiol ◽  
Amancio Carnero

AbstractThe EMX (Empty Spiracles Homeobox) genes EMX1 and EMX2 are two homeodomain gene members of the EMX family of transcription factors involved in the regulation of various biological processes, such as cell proliferation, migration, and differentiation, during brain development and neural crest migration. They play a role in the specification of positional identity, the proliferation of neural stem cells, and the differentiation of certain neuronal cell phenotypes. In general, they act as transcription factors in early embryogenesis and neuroembryogenesis from metazoans to higher vertebrates. The EMX1 and EMX2’s potential as tumor suppressor genes has been suggested in some cancers. Our work showed that EMX1/EMX2 act as tumor suppressors in sarcomas by repressing the activity of stem cell regulatory genes (OCT4, SOX2, KLF4, MYC, NANOG, NES, and PROM1). EMX protein downregulation, therefore, induced the malignance and stemness of cells both in vitro and in vivo. In murine knockout (KO) models lacking Emx genes, 3MC-induced sarcomas were more aggressive and infiltrative, had a greater capacity for tumor self-renewal, and had higher stem cell gene expression and nestin expression than those in wild-type models. These results showing that EMX genes acted as stemness regulators were reproduced in different subtypes of sarcoma. Therefore, it is possible that the EMX genes could have a generalized behavior regulating proliferation of neural crest-derived progenitors. Together, these results indicate that the EMX1 and EMX2 genes negatively regulate these tumor-altering populations or cancer stem cells, acting as tumor suppressors in sarcoma.


e-Polymers ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 87-91 ◽  
Author(s):  
Jiankang Zhou ◽  
Kun Zhang ◽  
Shanshan Ma ◽  
Tengfei Liu ◽  
Minghao Yao ◽  
...  

AbstractIn the past few decades, stem cell transplantation has been generally accepted as an effective method on the treatment of tissue and organ injury. However, the insufficient number of transplanted stem cells and low survival rate that caused by series of negative conditions limit the therapeutic effect. In this contribution, we developed an injectable hydrogel composed of sodium alginate (SA) and Type I collagen (ColI), as the tissue scaffold to create better growth microenvironment for the stem cells. Compared the traditional SA scaffold, the ColI/SA hydrogel inherits its biomimetic properties, and simultaneously has shorter gelation time which means less loss of the transplanted stem cells. The mesenchyma stem cell (MSC) culture experiments indicated that the ColI/SA hydrogel could prevent the MSC apoptosis and contributed to faster MSC proliferation. It is highlighted that this ColI/SA hydrogel may have potential application for tissue regeneration and organ repair as the stem cell scaffold.


2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Dajeong Yoon ◽  
Dogeon Yoon ◽  
Heejoong Sim ◽  
Inseok Hwang ◽  
Ji-Seon Lee ◽  
...  

Fibroblasts synthesize and secrete dermal collagen, matrix proteins, growth factors, and cytokines. These characteristics of fibroblasts provide a potential way for fibroblast therapy to treat skin ulcers more effectively than conventional therapies such as cytokine therapy and negative pressure wound therapy. However, the obstacle to the commercialization of fibroblast therapy is the limited supply of cells with consistent quality. In this study, we tested whether human embryonic stem cell-derived mesenchymal stem cells (hESC-MSCs) could be differentiated into fibroblasts considering that they have characteristics of high differentiation rates, unlimited proliferation possibility from a single colony, and homogeneity. As a result, hESC-MSC-derived fibroblasts (hESC-MSC-Fbs) showed a significant increase in the expression of type I and III collagen, fibronectin, and fibroblast-specific protein-1 (FSP-1). Besides, vessel formation and wound healing were enhanced in hESC-MSC-Fb-treated skin tissues compared to PBS- or hESC-MSC-treated skin tissues, along with decreased IL-6 expression at 4 days after the formation of pressure ulcer wound in a mouse model. In view of the limited available cell sources for fibroblast therapy, hESC-MSC-Fbs show a promising potential as a commercial cell therapy source to treat skin ulcers.


2018 ◽  
Vol 115 (4) ◽  
pp. E610-E619 ◽  
Author(s):  
Onur Basak ◽  
Teresa G. Krieger ◽  
Mauro J. Muraro ◽  
Kay Wiebrands ◽  
Daniel E. Stange ◽  
...  

The adult mouse subependymal zone provides a niche for mammalian neural stem cells (NSCs). However, the molecular signature, self-renewal potential, and fate behavior of NSCs remain poorly defined. Here we propose a model in which the fate of active NSCs is coupled to the total number of neighboring NSCs in a shared niche. Using knock-in reporter alleles and single-cell RNA sequencing, we show that the Wnt target Tnfrsf19/Troy identifies both active and quiescent NSCs. Quantitative analysis of genetic lineage tracing of individual NSCs under homeostasis or in response to injury reveals rapid expansion of stem-cell number before some return to quiescence. This behavior is best explained by stochastic fate decisions, where stem-cell number within a shared niche fluctuates over time. Fate mapping proliferating cells using a Ki67iresCreER allele confirms that active NSCs reversibly return to quiescence, achieving long-term self-renewal. Our findings suggest a niche-based mechanism for the regulation of NSC fate and number.


2012 ◽  
Vol 24 (1) ◽  
pp. 221
Author(s):  
S. A. Ock ◽  
G. H. Maeng ◽  
Y. M. Lee ◽  
T. H. Kim ◽  
B. M. Kumar ◽  
...  

Canine mesenchymal stem cells (cMSC) have been successfully isolated from several adult tissue sources. However, differences in the biological properties of MSC have been shown to be associated with donor variability. Further, the stem cell capacity of cMSC of various tissues isolated from a single donor is currently unclear. Therefore, this study investigated the functional and molecular characteristics of cMSC derived from bone marrow (cBM-MSC), adipose tissue (cA-MSC) and dermal skin (cDS-MSC) of a single donor. Three kinds of cMSC were isolated by following previously published protocols. AP activity was assessed with a chromogen kit (Abcam Inc., Cambridge, MA, USA). Expression of CD markers (CD45, 90 and 105) and stem cell transcription factors (Oct3/4, Nanog and Sox2) was analysed by immunocytochemical staining. All cells were induced into osteogenesis and adipogenesis by following protocols described earlier and confirmed by cytochemical staining and the detection of lineage specific genes by RT-PCR. Chromosomal stability was assessed by a method described earlier (Ock and Rho 2008 J. Vet. Med. Sci. 70, 1165–1172) and cell cycle status was determined by a flow cytometry. Telomere length was analysed by Telo TAGGG Telomere Length Assay kit (Roche, Mannheim, Germany) and telomerase activity was evaluated by semiquantitative nested RT-PCR. Statistical analysis was performed by ANOVA using SPSS 12.0 and significance was tested when P < 0.05. Expressions of AP activity and the transcription factors, such as Oct3/4, Nanog and Sox2 were absent in all cMSC. All 3 types of cMSC positively expressed the surface markers CD90 and 105 but not CD45. Exposure of all cell lines to osteogenic and adipogenic induction medium resulted in the calcium deposition evidenced by Alizarin red S staining and the accumulation of fat globules indicated by Oil red O staining, respectively. Differentiation was further confirmed by the detection of marker genes, such as Runx2 and Pparγ. However, the degree of osteogenic or adipogenic differentiation among the 3 kinds of cMSC was different and particularly, cA-MSC had enhanced cytochemical staining associated with expression of specific genes, Runx2 and Pparγ. Ploidy analysis showed that the diploid rate was high with over 90% in all cMSC and indicated no noticeable chromosomal abnormalities. Further, less than 52% of cells were found at G1 phase in all cMSC, with lowest percentage observed in cDS-MSC (33.3%). Regardless of varied tissue sources, cMSC from a single donor showed no differences in telomere lengths (∼18–19 kbp), but the telomerase activity was different with significantly higher levels found in cBM-MSC. In conclusion, the above results suggest that tissue specific cMSC derived from a single donor possess differences in stem cell capacity and support the consideration of tissue source before judging the suitability of cells for therapeutic applications. This work was supported by grant from Basic Science Research Program through NRF funded by the Ministry of Education, Science and Technology (2009-0064229).


1999 ◽  
Vol 189 (7) ◽  
pp. 1139-1148 ◽  
Author(s):  
Mickie Bhatia ◽  
Dominique Bonnet ◽  
Dongmei Wu ◽  
Barbara Murdoch ◽  
Jeff Wrana ◽  
...  

The identification of molecules that regulate human hematopoietic stem cells has focused mainly on cytokines, of which very few are known to act directly on stem cells. Recent studies in lower organisms and the mouse have suggested that bone morphogenetic proteins (BMPs) may play a critical role in the specification of hematopoietic tissue from the mesodermal germ layer. Here we report that BMPs regulate the proliferation and differentiation of highly purified primitive human hematopoietic cells from adult and neonatal sources. Populations of rare CD34+CD38−Lin− stem cells were isolated from human hematopoietic tissue and were found to express the BMP type I receptors activin-like kinase (ALK)-3 and ALK-6, and their downstream transducers SMAD-1, -4, and -5. Treatment of isolated stem cell populations with soluble BMP-2, -4, and -7 induced dose-dependent changes in proliferation, clonogenicity, cell surface phenotype, and multilineage repopulation capacity after transplantation in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. Similar to transforming growth factor β, treatment of purified cells with BMP-2 or -7 at high concentrations inhibited proliferation yet maintained the primitive CD34+CD38− phenotype and repopulation capacity. In contrast, low concentrations of BMP-4 induced proliferation and differentiation of CD34+ CD38−Lin− cells, whereas at higher concentrations BMP-4 extended the length of time that repopulation capacity could be maintained in ex vivo culture, indicating a direct effect on stem cell survival. The discovery that BMPs are capable of regulating repopulating cells provides a new pathway for controlling human stem cell development and a powerful model system for studying the biological mechanism of BMP action using primary human cells.


PPAR Research ◽  
2007 ◽  
Vol 2007 ◽  
pp. 1-13 ◽  
Author(s):  
K. R. Shockley ◽  
C. J. Rosen ◽  
G. A. Churchill ◽  
B. Lecka-Czernik

Bone formation and hematopoiesis are anatomically juxtaposed and share common regulatory mechanisms. Bone marrow mesenchymal stromal/stem cells (MSC) contain a compartment that provides progeny with bone forming osteoblasts and fat laden adipocytes as well as fibroblasts, chondrocytes, and muscle cells. In addition, marrow MSC provide an environment for support of hematopoiesis, including the development of bone resorbing osteoclasts. The PPARγ2 nuclear receptor is an adipocyte-specific transcription factor that controls marrow MSC lineage allocation toward adipocytes and osteoblasts. Increased expression of PPARγ2 with aging correlates with changes in the MSC status in respect to both their intrinsic differentiation potential and production of signaling molecules that contribute to the formation of a specific marrow microenvironment. Here, we investigated the effect of PPARγ2 on MSC molecular signature in respect to the expression of gene markers associated exclusively with stem cell phenotype, as well as genes involved in the formation of a stem cell supporting marrow environment. We found that PPARγ2 is a powerful modulator of stem cell-related gene expression. In general, PPARγ2 affects the expression of genes specific for the maintenance of stem cell phenotype, including LIF, LIF receptor, Kit ligand, SDF-1, Rex-1/Zfp42, and Oct-4. Moreover, the antidiabetic PPARγagonist TZD rosiglitazone specifically affects the expression of “stemness” genes, including ABCG2, Egfr, and CD44. Our data indicate that aging and antidiabetic TZD therapy may affect mesenchymal stem cell phenotype through modulation of PPARγ2 activity. These observations may have important therapeutic consequences and indicate a need for more detailed studies of PPARγ2 role in stem cell biology.


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