Mohammad Massumi - Academia.edu (original) (raw)

Papers by Mohammad Massumi

Research paper thumbnail of Inductive effect of IDE1 on differentiation of human induced pluripotent stem cells into definitive endoderm cells by using PCL nanofibrous scaffold

Nova Biologica Reperta, 2014

Research paper thumbnail of Bispecific immune cell engager enhances the anticancer activity of CD16+ NK cells and macrophages in vitro, and eliminates cancer metastasis in NK humanized NOG mice

Journal for immunotherapy of cancer, Mar 1, 2024

Research paper thumbnail of The effect of overexpression of Pdx1 on the differentiation of induced pluripotent stem cells derived from fibroblast of diabetic patient into pancreatic cells

Journal of Stem Cell Research & Therapy, Sep 3, 2015

Research paper thumbnail of Signaling and Gene Regulatory Networks Governing Definitive Endoderm Derivation From Pluripotent Stem Cells

Journal of Cellular Physiology, Jan 28, 2016

The generation of definitive endoderm (DE) from pluripotent stem cells (PSCs) is a fundamental st... more The generation of definitive endoderm (DE) from pluripotent stem cells (PSCs) is a fundamental stage in the formation of highly organized visceral organs, such as the liver and pancreas. Currently, there is a need for a comprehensive study that illustrates the involvement of different signaling pathways and their interactions in the derivation of DE cells from PSCs. This study aimed to identify signaling pathways that have the greatest influence on DE formation using analyses of transcriptional profiles, protein-protein interactions, protein-DNA interactions, and protein localization data. Using this approach, signaling networks involved in DE formation were constructed using systems biology and data mining tools, and the validity of the predicted networks was confirmed experimentally by measuring the mRNA levels of hub genes in several PSCs-derived DE cell lines. Based on our analyses, seven signaling pathways, including the BMP, ERK1-ERK2, FGF, TGF-beta, MAPK, Wnt, and PIP signaling pathways and their interactions, were found to play a role in the derivation of DE cells from PSCs. Lastly, the core gene regulatory network governing this differentiation process was constructed. The results of this study could improve our understanding surrounding the efficient generation of DE cells for the regeneration of visceral organs.

Research paper thumbnail of High neuronal/astroglial differentiation plasticity of adult rat hippocampal neural stem/progenitor cells in response to the effects of embryonic and adult cerebrospinal fluids

PubMed, 2015

Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important... more Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important sources of neuronal and gial cell production. In this study, the main goal is to investigate the plasticity of these cells in neuronal/astroglial differentiations. To this end, the differentiation of the hipp-NS/PCs isolated from 3-month-old Wistar rats was investigated in response to the embryonic cerebrospinal fluid (E-CSF) including E13.5, E17-CSF and the adult cerebrospinal fluid (A-CSF), all extracted from rats. CSF samples were selected based on their effects on cell behavioral parameters. Primary cell culture was performed in the presence of either normal or high levels of KCL in a culture medium. High levels of KCL cause cell depolarization, and thus the activation of quiescent NSCs. Results from immunocytochemistry (ICC) and semi-quantitative RT-PCR (sRT-PCR) techniques showed that in E-CSF-treated groups, neuronal differentiation increased (E17>E13.5). In contrast, A-CSF decreased and increased neuronal and astroglial differentiations, respectively. Cell survivability and/or proliferation (S/P), evaluated by an MTT assay, increased by E13.5 CSF, but decreased by both E17 CSF and A-CSF. Based on the results, it is finally concluded that adult rat hippocampal proliferative cells are not restricted progenitors but rather show high plasticity in neuronal/astroglial differentiation according to the effects of CSF samples. In addition, using high concentrations of KCL in the primary cell culture led to an increase in the number of NSCs, which in turn resulted in the increase in neuronal or astroglial differentiations after CSF treatment.

Research paper thumbnail of L-Ascorbic acid affect the DNA methytransferase expression in Mouse Embryonic Fibroblasts

Journal of "Regeneration, Reconstruction & Restoration" (Triple R), Sep 17, 2017

Induced pluripotent stem cells (iPSCs) can be generated from different source of cells with diffe... more Induced pluripotent stem cells (iPSCs) can be generated from different source of cells with different efficiencies. Two DNA methyltransferases DNMT1 and DNMT3A have been shown to regulate epigenetically the gene expression involved in cell viability and reprogramming. L-ascorbic acid (L-AA) is a chemical factor that can accelerate reprogramming. Here, we sought to investigate the effect of L-AA on DNMT1 and DNMT3A expressions. Materials and Methods: First, mouse embryonic fibroblasts at passage 3 were cultured in the presence of 10 µg/ml L-AA days for 5 days. Then, DNMT1 and DNMT3A expressions were determined using real-time PCR at days 3 and 5. Results: It was showed that L-AA could enhance DNMT-1 expression which involve in cell viability and decrease the DNMT3A which involve in cell differentiation. Conclusion: The results therefore suggest a new insight into L-AA mechanism impact on reprogramming process.

Research paper thumbnail of Design and production of a cell line expressing 5′UTR and NS3 genes of bovine viral diarrhea virus (BVDV) in order to evaluate the efficacy of treatments against this virus

Journal of Veterinary Research, 2014

Research paper thumbnail of Involvement of Polycomb Repressive Complex 2 in Maturation of Induced Pluripotent Stem Cells during Reprogramming of Mouse and Human Fibroblasts

PLOS ONE, Mar 3, 2016

Induced pluripotent stem cells (iPSCs) provide a reliable source for the study of regenerative me... more Induced pluripotent stem cells (iPSCs) provide a reliable source for the study of regenerative medicine, drug discovery, and developmental biology. Despite extensive studies on the reprogramming of mouse and human fibroblasts into iPSCs, the efficiency of reprogramming is still low. Here, we used a bioinformatics and systems biology approach to study the two gene regulatory waves governing the reprogramming of mouse and human fibroblasts into iPSCs. Our results revealed that the maturation phase of reprogramming was regulated by a more complex regulatory network of transcription factors compared to the initiation phase. Interestingly, in addition to pluripotency factors, the polycomb repressive complex 2 (PRC2) members Ezh2, Eed, Jarid2, Mtf2, and Suz12 are crucially recruited during the maturation phase of reprogramming. Moreover, we found that during the maturation phase of reprogramming, pluripotency factors, via the expression and induction of PRC2 complex members, could silence the lineage-specific gene expression program and maintain a ground state of pluripotency in human and mouse naïve iPSCs. The findings obtained here provide us a better understanding of the gene regulatory network (GRN) that governs reprogramming, and the maintenance of the naïve state of iPSCs.

Research paper thumbnail of Combined cell and gene therapy towards the treatment of age-related macular degeneration and diabetic retinopathy

Research paper thumbnail of シグナル伝達と遺伝子調節ネットワークを支配する根治的内胚葉誘導多能性幹細胞から【Powered by NICT】

Journal of Cellular Physiology, 2016

Research paper thumbnail of See Profile

All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.

Research paper thumbnail of Murine ES-derived pancreatic acinar cells recapitulate features of early pancreatic differentiation

Background & Aims—Acinar cells constitute 90% of the pancreas epithelium, are polarized, and secr... more Background & Aims—Acinar cells constitute 90% of the pancreas epithelium, are polarized, and secrete digestive enzymes. These cells play a crucial role in pancreatitis and pancreatic cancer. However, there are no models to study normal acinar cell differentiation in vitro. The aim of this work was to generate and characterize purified populations of pancreatic acinar cells from embryonic stem cells (ES). Methods—Reporter ES cells (Ela-pur) were generated that stably expressed both beta-galactosidase and puromycin resistance genes under the control of the elastase I promoter. Directed differentiation was achieved by incubation with conditioned media (CM) of cultured foetal pancreatic rudiments Correspondence: Anouchka Skoudy; address: IMIM-PRBB, Dr Aiguader 88, 08003 Barcelona, Spain; phone: + 34 93 3160431; Fax: + 34 93 3160410; email: askoudy@imim.es. ∫These two authors contributed equally to the work. ¶¶Present address: Centro Nacional de Investigaciones Oncológicas, Melchor Ferná...

Research paper thumbnail of L-Ascorbic acid affect the DNA methytransferase expression in Mouse Embryonic Fibroblasts

Introduction: Induced pluripotent stem cells (iPSCs) can be generated from different source of ce... more Introduction: Induced pluripotent stem cells (iPSCs) can be generated from different source of cells with different efficiencies. Two DNA methyltransferases DNMT1 and DNMT3A have been shown to regulate epigenetically the gene expression involved in cell viability and reprogramming. L-ascorbic acid (L-AA) is a chemical factor that can accelerate reprogramming. Here, we sought to investigate the effect of L-AA on DNMT1 and DNMT3A expressions. Materials and Methods : First, mouse embryonic fibroblasts at passage 3 were cultured in the presence of 10 µg/ml L-AA days for 5 days. Then, DNMT1 and DNMT3A expressions were determined using real-time PCR at days 3 and 5. Results: It was showed that L-AA could enhance DNMT-1 expression which involve in cell viability and decrease the DNMT3A which involve in cell differentiation. Conclusion: The results therefore suggest a new insight into L-AA mechanism impact on reprogramming process.

Research paper thumbnail of Ps-19: Human Endometrial Stem Cells Attain Oligodendrocyte Features In Vitro

Objective: Human endometrial-derived stem cells (En- SCs) are the abundant and easy available sou... more Objective: Human endometrial-derived stem cells (En- SCs) are the abundant and easy available source for cell replacement therapy. Oligodendrocytes are myelinating cells in the central nervous system (CNS) that form the myelin sheath of axons to support rapid nerve conduction. In CNS disorders, such as stroke, multiple sclerosis and spinal cord injury, demyelination of axons contributes to functional deficit. Materials and Methods: The characterized cells were coaxed to oligodendrocyte differentiation by induction of bFGF, EGF and PDGF-AA (20 ng/ml) signaling molecules for 21 days and T3 (30 ng/ml) for 8 days. Differentiated cells were analyzed for expression of neuronal markers by RT-PCR and Immunocytochemistry. Results: The flow cytometric analysis showed that En- SCs were positive for CD90, CD105, OCT4 and were negative for CD31, CD34. The result showed the expression profile of oligodendrocyte markers such as Nestin, Olig2, PDGFRa, CNP in the level of mRNA. The expression of Oli...

Research paper thumbnail of Results Digestive Enzyme Gene Expression Is Not Activated as a Single Regulatory Module During Pancreatic Development

Research paper thumbnail of Induction of long-term allogeneic cell acceptance and formation of immune privileged tissue in immunocompetent hosts

ABSTRACTA vast number of diseases could be treated with therapeutic cells derived from pluripoten... more ABSTRACTA vast number of diseases could be treated with therapeutic cells derived from pluripotent stem cells (PSCs). However, cell products that come from non-autologous sources can be immune rejected by the recipient’s immune system. Here, we show that forced expression of eight immunomodulatory transgenes, includingCcl21, Pdl1, Fasl, Serpinb9, H2-M3, Cd47, Cd200, andMfge8, allows mouse embryonic stem cells (mESCs) and their derivatives to escape immune rejection in fully immunocompetent, allogeneic recipients. Despite no genetic alterations to major histocompatibility complex (MHC) genes, immune-modified C57BL/6 mESCs could generate long-term, allogeneic tissues in inbred FVB/N, C3H, and BALB/c, as well as outbred CD-1 recipients. Due to the tandem incorporation of our safe-cell suicide system, which allows tight and drug-inducible control over proliferationin vivo, these allotolerated cells can generate safe and dormant ectopic tissues in the host. We show that these ectopic tis...

Research paper thumbnail of Glucose-Responsiveness of Pancreatic β-Like (GRP β-L) Cells Generated from Human Pluripotent Stem Cells

Current protocols in human genetics, Jan 18, 2018

The International Diabetic Federation estimated that 415 million adults currently have diabetes a... more The International Diabetic Federation estimated that 415 million adults currently have diabetes and 318 million adults had impaired glucose tolerance, putting them at high risk of developing diabetes in the future. In Type 1 Diabetes (T1D), the β cells are lost because of autoimmune reactions. Although islet transplantation has been a promising therapy for T1D, it is greatly limited by pancreatic donors. Here, we describe a protocol to generate glucose- responsive pancreatic β-like (GRPβ-L) cells from human-induced pluripotent stem (iPS) cells. We recapitulate in vivo pancreas development by in vitro induction of differentiating human (iPS) cells with stage-specific signaling molecules and proteins. Inhibition of Tyrosine Kinase receptor AXL, TGF-β, and Notch signaling pathways in the final stage of the five-stage protocol could efficiently generate GRPβ-L from the endocrine progenitor. Differentiation of human iPS cells through the protocol could result in functional GRPβ-L cells, ...

Research paper thumbnail of Optimization of Lentiviral Transduction Procedure for the Generation of Human Induced Pluripotent Stem Cells

Journal of Biomedicine, 2016

Background: Human somatic cells are reprogrammed to induced pluripotent stem (iPS) cells when fou... more Background: Human somatic cells are reprogrammed to induced pluripotent stem (iPS) cells when four transcription factors (Oct4, Sox2, Klf4, and Myc) are ectopically expressed in them. These iPS cells, which evade immunological rejection, are a valuable source for patient-specific cell therapy. Lentiviral systems have been proved to be powerful tools for cellular reprogramming, an example of which is the induction of iPS cells from somatic cells that requires a high transduction efficiency of lentiviruses harboring the four reprogramming factors. Objectives: The purpose of this study was to define an optimized calcium phosphate transfection method to produce high-titer lentiviral vectors for the generation of human iPS cells. Materials and Methods: In this study, the calcium phosphate transfection method was used to generate lentiviruses. The virus supernatant was concentrated using Amicon Ultra-4 column. Results: This method resulted in 80% GFP-positive cells and viral preparations of 2.4 × 10 8 viral particles/mL. Conclusions: This method is both cost effective and simple to adopt.

Research paper thumbnail of Improved human endometrial stem cells differentiation into functional hepatocyte-like cells on a glycosaminoglycan/collagen-grafted polyethersulfone nanofibrous scaffold

Journal of biomedical materials research. Part B, Applied biomaterials, Jan 30, 2016

Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engine... more Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engineering and biological processes to compensate for the shortage of damaged or destroyed liver tissues. We examined the viability, differentiation, and integration of hepatocyte-like cells on an electrospun polyethersulfone (PES) scaffold, derived from human endometrial stem cells (hEnSCs). Natural polymers were separately grafted on plasma-treated PES nanofibers, that is, collagen, heparan sulfate (HS) and collagen-HS. Galactosilated PES (PES-Gal) nanofibrous were created. The engineering and cell growth parameters were considered and compared with each sample. The cellular studies revealed increased cell survival, attachment, and normal morphology on the bioactive natural polymer-grafted scaffolds after 30 days of hepatic differentiation. The chemical and molecular assays displayed hepatocyte differentiation. These cells were also functional, showing glycogen storage, α-fetoprotein, and a...

Research paper thumbnail of Efficient generation of dopaminergic-like neurons by overexpression of Nurr1 and Pitx3 in mouse induced Pluripotent Stem Cells

Neuroscience Letters, 2016

Parkinson's disea... more Parkinson's disease (PD) is a neurodegenerative disorder, in which the nigro-striatal Dopaminergic (DAergic) neurons are selectively lost. Treatment of neurodegenerative diseases with Pluripotent Stem Cells (PSCs) is a big interest in cell therapy. Here, we used induced Pluripotent Stem Cells (iPSCs) expressing two master Dopaminergic (DAergic) transcription factors, i.e. Nurr1 and Pitx3, to generate functional in vitro DAergic-like neurons. After establishment and characterization of Doxycycline-inducible iPSCs from mouse fibroblasts, the cells were transduced by NURR1- and PITX3-harboring lentiviruses. The Nurr1/Pitx3 -iPSCs were differentiated through a five-stage protocol to generate DAergic-like neurons. The results confirmed the efficient expression of DAergic neuron markers in the end of protocol. Beside, the generated cells could exclusively synthesize and secrete Dopamine in response to secretagogues. In conclusion, overexpression of Nurr1 and Pitx3 in iPSCs could efficiently program iPSCs into functional DAergic-like neurons. This finding may have an impact on future stem cell therapy of PD.

Research paper thumbnail of Inductive effect of IDE1 on differentiation of human induced pluripotent stem cells into definitive endoderm cells by using PCL nanofibrous scaffold

Nova Biologica Reperta, 2014

Research paper thumbnail of Bispecific immune cell engager enhances the anticancer activity of CD16+ NK cells and macrophages in vitro, and eliminates cancer metastasis in NK humanized NOG mice

Journal for immunotherapy of cancer, Mar 1, 2024

Research paper thumbnail of The effect of overexpression of Pdx1 on the differentiation of induced pluripotent stem cells derived from fibroblast of diabetic patient into pancreatic cells

Journal of Stem Cell Research & Therapy, Sep 3, 2015

Research paper thumbnail of Signaling and Gene Regulatory Networks Governing Definitive Endoderm Derivation From Pluripotent Stem Cells

Journal of Cellular Physiology, Jan 28, 2016

The generation of definitive endoderm (DE) from pluripotent stem cells (PSCs) is a fundamental st... more The generation of definitive endoderm (DE) from pluripotent stem cells (PSCs) is a fundamental stage in the formation of highly organized visceral organs, such as the liver and pancreas. Currently, there is a need for a comprehensive study that illustrates the involvement of different signaling pathways and their interactions in the derivation of DE cells from PSCs. This study aimed to identify signaling pathways that have the greatest influence on DE formation using analyses of transcriptional profiles, protein-protein interactions, protein-DNA interactions, and protein localization data. Using this approach, signaling networks involved in DE formation were constructed using systems biology and data mining tools, and the validity of the predicted networks was confirmed experimentally by measuring the mRNA levels of hub genes in several PSCs-derived DE cell lines. Based on our analyses, seven signaling pathways, including the BMP, ERK1-ERK2, FGF, TGF-beta, MAPK, Wnt, and PIP signaling pathways and their interactions, were found to play a role in the derivation of DE cells from PSCs. Lastly, the core gene regulatory network governing this differentiation process was constructed. The results of this study could improve our understanding surrounding the efficient generation of DE cells for the regeneration of visceral organs.

Research paper thumbnail of High neuronal/astroglial differentiation plasticity of adult rat hippocampal neural stem/progenitor cells in response to the effects of embryonic and adult cerebrospinal fluids

PubMed, 2015

Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important... more Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important sources of neuronal and gial cell production. In this study, the main goal is to investigate the plasticity of these cells in neuronal/astroglial differentiations. To this end, the differentiation of the hipp-NS/PCs isolated from 3-month-old Wistar rats was investigated in response to the embryonic cerebrospinal fluid (E-CSF) including E13.5, E17-CSF and the adult cerebrospinal fluid (A-CSF), all extracted from rats. CSF samples were selected based on their effects on cell behavioral parameters. Primary cell culture was performed in the presence of either normal or high levels of KCL in a culture medium. High levels of KCL cause cell depolarization, and thus the activation of quiescent NSCs. Results from immunocytochemistry (ICC) and semi-quantitative RT-PCR (sRT-PCR) techniques showed that in E-CSF-treated groups, neuronal differentiation increased (E17>E13.5). In contrast, A-CSF decreased and increased neuronal and astroglial differentiations, respectively. Cell survivability and/or proliferation (S/P), evaluated by an MTT assay, increased by E13.5 CSF, but decreased by both E17 CSF and A-CSF. Based on the results, it is finally concluded that adult rat hippocampal proliferative cells are not restricted progenitors but rather show high plasticity in neuronal/astroglial differentiation according to the effects of CSF samples. In addition, using high concentrations of KCL in the primary cell culture led to an increase in the number of NSCs, which in turn resulted in the increase in neuronal or astroglial differentiations after CSF treatment.

Research paper thumbnail of L-Ascorbic acid affect the DNA methytransferase expression in Mouse Embryonic Fibroblasts

Journal of "Regeneration, Reconstruction & Restoration" (Triple R), Sep 17, 2017

Induced pluripotent stem cells (iPSCs) can be generated from different source of cells with diffe... more Induced pluripotent stem cells (iPSCs) can be generated from different source of cells with different efficiencies. Two DNA methyltransferases DNMT1 and DNMT3A have been shown to regulate epigenetically the gene expression involved in cell viability and reprogramming. L-ascorbic acid (L-AA) is a chemical factor that can accelerate reprogramming. Here, we sought to investigate the effect of L-AA on DNMT1 and DNMT3A expressions. Materials and Methods: First, mouse embryonic fibroblasts at passage 3 were cultured in the presence of 10 µg/ml L-AA days for 5 days. Then, DNMT1 and DNMT3A expressions were determined using real-time PCR at days 3 and 5. Results: It was showed that L-AA could enhance DNMT-1 expression which involve in cell viability and decrease the DNMT3A which involve in cell differentiation. Conclusion: The results therefore suggest a new insight into L-AA mechanism impact on reprogramming process.

Research paper thumbnail of Design and production of a cell line expressing 5′UTR and NS3 genes of bovine viral diarrhea virus (BVDV) in order to evaluate the efficacy of treatments against this virus

Journal of Veterinary Research, 2014

Research paper thumbnail of Involvement of Polycomb Repressive Complex 2 in Maturation of Induced Pluripotent Stem Cells during Reprogramming of Mouse and Human Fibroblasts

PLOS ONE, Mar 3, 2016

Induced pluripotent stem cells (iPSCs) provide a reliable source for the study of regenerative me... more Induced pluripotent stem cells (iPSCs) provide a reliable source for the study of regenerative medicine, drug discovery, and developmental biology. Despite extensive studies on the reprogramming of mouse and human fibroblasts into iPSCs, the efficiency of reprogramming is still low. Here, we used a bioinformatics and systems biology approach to study the two gene regulatory waves governing the reprogramming of mouse and human fibroblasts into iPSCs. Our results revealed that the maturation phase of reprogramming was regulated by a more complex regulatory network of transcription factors compared to the initiation phase. Interestingly, in addition to pluripotency factors, the polycomb repressive complex 2 (PRC2) members Ezh2, Eed, Jarid2, Mtf2, and Suz12 are crucially recruited during the maturation phase of reprogramming. Moreover, we found that during the maturation phase of reprogramming, pluripotency factors, via the expression and induction of PRC2 complex members, could silence the lineage-specific gene expression program and maintain a ground state of pluripotency in human and mouse naïve iPSCs. The findings obtained here provide us a better understanding of the gene regulatory network (GRN) that governs reprogramming, and the maintenance of the naïve state of iPSCs.

Research paper thumbnail of Combined cell and gene therapy towards the treatment of age-related macular degeneration and diabetic retinopathy

Research paper thumbnail of シグナル伝達と遺伝子調節ネットワークを支配する根治的内胚葉誘導多能性幹細胞から【Powered by NICT】

Journal of Cellular Physiology, 2016

Research paper thumbnail of See Profile

All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.

Research paper thumbnail of Murine ES-derived pancreatic acinar cells recapitulate features of early pancreatic differentiation

Background & Aims—Acinar cells constitute 90% of the pancreas epithelium, are polarized, and secr... more Background & Aims—Acinar cells constitute 90% of the pancreas epithelium, are polarized, and secrete digestive enzymes. These cells play a crucial role in pancreatitis and pancreatic cancer. However, there are no models to study normal acinar cell differentiation in vitro. The aim of this work was to generate and characterize purified populations of pancreatic acinar cells from embryonic stem cells (ES). Methods—Reporter ES cells (Ela-pur) were generated that stably expressed both beta-galactosidase and puromycin resistance genes under the control of the elastase I promoter. Directed differentiation was achieved by incubation with conditioned media (CM) of cultured foetal pancreatic rudiments Correspondence: Anouchka Skoudy; address: IMIM-PRBB, Dr Aiguader 88, 08003 Barcelona, Spain; phone: + 34 93 3160431; Fax: + 34 93 3160410; email: askoudy@imim.es. ∫These two authors contributed equally to the work. ¶¶Present address: Centro Nacional de Investigaciones Oncológicas, Melchor Ferná...

Research paper thumbnail of L-Ascorbic acid affect the DNA methytransferase expression in Mouse Embryonic Fibroblasts

Introduction: Induced pluripotent stem cells (iPSCs) can be generated from different source of ce... more Introduction: Induced pluripotent stem cells (iPSCs) can be generated from different source of cells with different efficiencies. Two DNA methyltransferases DNMT1 and DNMT3A have been shown to regulate epigenetically the gene expression involved in cell viability and reprogramming. L-ascorbic acid (L-AA) is a chemical factor that can accelerate reprogramming. Here, we sought to investigate the effect of L-AA on DNMT1 and DNMT3A expressions. Materials and Methods : First, mouse embryonic fibroblasts at passage 3 were cultured in the presence of 10 µg/ml L-AA days for 5 days. Then, DNMT1 and DNMT3A expressions were determined using real-time PCR at days 3 and 5. Results: It was showed that L-AA could enhance DNMT-1 expression which involve in cell viability and decrease the DNMT3A which involve in cell differentiation. Conclusion: The results therefore suggest a new insight into L-AA mechanism impact on reprogramming process.

Research paper thumbnail of Ps-19: Human Endometrial Stem Cells Attain Oligodendrocyte Features In Vitro

Objective: Human endometrial-derived stem cells (En- SCs) are the abundant and easy available sou... more Objective: Human endometrial-derived stem cells (En- SCs) are the abundant and easy available source for cell replacement therapy. Oligodendrocytes are myelinating cells in the central nervous system (CNS) that form the myelin sheath of axons to support rapid nerve conduction. In CNS disorders, such as stroke, multiple sclerosis and spinal cord injury, demyelination of axons contributes to functional deficit. Materials and Methods: The characterized cells were coaxed to oligodendrocyte differentiation by induction of bFGF, EGF and PDGF-AA (20 ng/ml) signaling molecules for 21 days and T3 (30 ng/ml) for 8 days. Differentiated cells were analyzed for expression of neuronal markers by RT-PCR and Immunocytochemistry. Results: The flow cytometric analysis showed that En- SCs were positive for CD90, CD105, OCT4 and were negative for CD31, CD34. The result showed the expression profile of oligodendrocyte markers such as Nestin, Olig2, PDGFRa, CNP in the level of mRNA. The expression of Oli...

Research paper thumbnail of Results Digestive Enzyme Gene Expression Is Not Activated as a Single Regulatory Module During Pancreatic Development

Research paper thumbnail of Induction of long-term allogeneic cell acceptance and formation of immune privileged tissue in immunocompetent hosts

ABSTRACTA vast number of diseases could be treated with therapeutic cells derived from pluripoten... more ABSTRACTA vast number of diseases could be treated with therapeutic cells derived from pluripotent stem cells (PSCs). However, cell products that come from non-autologous sources can be immune rejected by the recipient’s immune system. Here, we show that forced expression of eight immunomodulatory transgenes, includingCcl21, Pdl1, Fasl, Serpinb9, H2-M3, Cd47, Cd200, andMfge8, allows mouse embryonic stem cells (mESCs) and their derivatives to escape immune rejection in fully immunocompetent, allogeneic recipients. Despite no genetic alterations to major histocompatibility complex (MHC) genes, immune-modified C57BL/6 mESCs could generate long-term, allogeneic tissues in inbred FVB/N, C3H, and BALB/c, as well as outbred CD-1 recipients. Due to the tandem incorporation of our safe-cell suicide system, which allows tight and drug-inducible control over proliferationin vivo, these allotolerated cells can generate safe and dormant ectopic tissues in the host. We show that these ectopic tis...

Research paper thumbnail of Glucose-Responsiveness of Pancreatic β-Like (GRP β-L) Cells Generated from Human Pluripotent Stem Cells

Current protocols in human genetics, Jan 18, 2018

The International Diabetic Federation estimated that 415 million adults currently have diabetes a... more The International Diabetic Federation estimated that 415 million adults currently have diabetes and 318 million adults had impaired glucose tolerance, putting them at high risk of developing diabetes in the future. In Type 1 Diabetes (T1D), the β cells are lost because of autoimmune reactions. Although islet transplantation has been a promising therapy for T1D, it is greatly limited by pancreatic donors. Here, we describe a protocol to generate glucose- responsive pancreatic β-like (GRPβ-L) cells from human-induced pluripotent stem (iPS) cells. We recapitulate in vivo pancreas development by in vitro induction of differentiating human (iPS) cells with stage-specific signaling molecules and proteins. Inhibition of Tyrosine Kinase receptor AXL, TGF-β, and Notch signaling pathways in the final stage of the five-stage protocol could efficiently generate GRPβ-L from the endocrine progenitor. Differentiation of human iPS cells through the protocol could result in functional GRPβ-L cells, ...

Research paper thumbnail of Optimization of Lentiviral Transduction Procedure for the Generation of Human Induced Pluripotent Stem Cells

Journal of Biomedicine, 2016

Background: Human somatic cells are reprogrammed to induced pluripotent stem (iPS) cells when fou... more Background: Human somatic cells are reprogrammed to induced pluripotent stem (iPS) cells when four transcription factors (Oct4, Sox2, Klf4, and Myc) are ectopically expressed in them. These iPS cells, which evade immunological rejection, are a valuable source for patient-specific cell therapy. Lentiviral systems have been proved to be powerful tools for cellular reprogramming, an example of which is the induction of iPS cells from somatic cells that requires a high transduction efficiency of lentiviruses harboring the four reprogramming factors. Objectives: The purpose of this study was to define an optimized calcium phosphate transfection method to produce high-titer lentiviral vectors for the generation of human iPS cells. Materials and Methods: In this study, the calcium phosphate transfection method was used to generate lentiviruses. The virus supernatant was concentrated using Amicon Ultra-4 column. Results: This method resulted in 80% GFP-positive cells and viral preparations of 2.4 × 10 8 viral particles/mL. Conclusions: This method is both cost effective and simple to adopt.

Research paper thumbnail of Improved human endometrial stem cells differentiation into functional hepatocyte-like cells on a glycosaminoglycan/collagen-grafted polyethersulfone nanofibrous scaffold

Journal of biomedical materials research. Part B, Applied biomaterials, Jan 30, 2016

Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engine... more Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engineering and biological processes to compensate for the shortage of damaged or destroyed liver tissues. We examined the viability, differentiation, and integration of hepatocyte-like cells on an electrospun polyethersulfone (PES) scaffold, derived from human endometrial stem cells (hEnSCs). Natural polymers were separately grafted on plasma-treated PES nanofibers, that is, collagen, heparan sulfate (HS) and collagen-HS. Galactosilated PES (PES-Gal) nanofibrous were created. The engineering and cell growth parameters were considered and compared with each sample. The cellular studies revealed increased cell survival, attachment, and normal morphology on the bioactive natural polymer-grafted scaffolds after 30 days of hepatic differentiation. The chemical and molecular assays displayed hepatocyte differentiation. These cells were also functional, showing glycogen storage, α-fetoprotein, and a...

Research paper thumbnail of Efficient generation of dopaminergic-like neurons by overexpression of Nurr1 and Pitx3 in mouse induced Pluripotent Stem Cells

Neuroscience Letters, 2016

Parkinson's disea... more Parkinson's disease (PD) is a neurodegenerative disorder, in which the nigro-striatal Dopaminergic (DAergic) neurons are selectively lost. Treatment of neurodegenerative diseases with Pluripotent Stem Cells (PSCs) is a big interest in cell therapy. Here, we used induced Pluripotent Stem Cells (iPSCs) expressing two master Dopaminergic (DAergic) transcription factors, i.e. Nurr1 and Pitx3, to generate functional in vitro DAergic-like neurons. After establishment and characterization of Doxycycline-inducible iPSCs from mouse fibroblasts, the cells were transduced by NURR1- and PITX3-harboring lentiviruses. The Nurr1/Pitx3 -iPSCs were differentiated through a five-stage protocol to generate DAergic-like neurons. The results confirmed the efficient expression of DAergic neuron markers in the end of protocol. Beside, the generated cells could exclusively synthesize and secrete Dopamine in response to secretagogues. In conclusion, overexpression of Nurr1 and Pitx3 in iPSCs could efficiently program iPSCs into functional DAergic-like neurons. This finding may have an impact on future stem cell therapy of PD.