Generation of Blood Cells from Human Ips Cells in Vitro through the Hematopoietic Progenitors Concentrated within the Unique Structures, Ips-Sac.

Abstract Human embryonic stem cells (hESCs) are proposed as an alternative source for transfusion therapy or studies of hematopoiesis. We have recently established an in vitro culture system whereby hESCs can be differentiated into hematopoietic progenitors within the ‘unique sac-like structures’ (ES-sacs), that are able to produce megakaryocytes and platelets (Takayama et al., Blood, 111, 5298–306, 2008). However there is a little concern that repetitive transfusion with same human ESC-derived platelets may induce immunological rejection against transfused platelets expressing allogenic HLA. Meanwhile, induced pluripotent stem (iPS) cells established from donor with identical HLA are well known as a potential and given source on platelet transfusion devoid of rejection. To examine if human iPS cells could generate platelets as well as from hESCs, we utilized 3 different human iPS cell lines; two were induced by transduction of 4 genes (Oct3/4, Klf4, Sox2, and c-Myc) in adult dermal fibroblasts, and one was by 3 genes without c-Myc. Sac-like structures (iPS-sac), inducible from 3 iPS cell lines, concentrated hematopoietic progenitors that expressed early hemato-endothelial markers, such as CD34, CD31, CD41a (integrin αIIb) and CD45. These progenitors were able to form hematopoietic colonies in semi-solid culture and differentiate into several blood cells including leukocytes, erythrocytes or platelets. Of these, obtained platelets responded to agonist stimulation, in which the function was as much as human ESC-derived platelets, as evidenced by PAC-1 binding with activated αIIbβ3 integrin or full spreading onto fibrinogen. These results collectively indicated that human dermal fibroblasts could generate functional and mature hematopoietic cells through the reprogramming process and this method may be useful for basic studies of hematopoietic disorders and clinical therapy in the future.

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Analyzing the Stepwise Developmental Pathway From ES/IPS Cells to Functional Mature Erythrocytes.

Blood ◽

10.1182/blood.v114.22.2534.2534 ◽

2009 ◽

Vol 114 (22) ◽

pp. 2534-2534

Author(s):

Akira Niwa ◽

Tomoki Fukatsu ◽

Katsutsugu Umeda ◽

Itaru Kato ◽

Hiromi Sakai ◽

...

Keyword(s):

Red Blood Cells ◽

Blood Cells ◽

Conflicts Of Interest ◽

Specific Antigen ◽

Embryonic Stem ◽

Ips Cells ◽

Oxygen Carriers ◽

Developmental Pathway ◽

Ips Cell

Abstract Abstract 2534 Poster Board II-511 Induced pluripotent stem (iPS) cells, reprogrammed somatic cells with embryonic stem (ES) cell–like characteristics, are generated by the introduction of combinations of specific transcription factors. Despite the controversy surrounding the gene manipulation, it is expected that iPS cells should contribute to regenerative medicine, disease investigation, drug screening, toxicology, and drug development in future. In the fields of hematology, iPS cells could become used as a new feasible source for transplantation therapy without immunological barrier and for the investigation of various kinds of hematological defects. Previous studies on ES / iPS cells have already demonstrated that they can develop into various lineages of hematopoietic cells including erythrocytes following the similar processes occurred in embryo and fetus. However, it is important to establish the more effective system for developing functional blood cells. Here we present the methods for selectively inducing mature red blood cells from ES / iPS cells in vitro, and show the functional equality of them to natural blood cells. First, Flk1+ mesodermal progenitors were derived from ES / iPS cells on OP9 stromal cells at an efficacy of more than 50% and collected by fluorescence activated cell sorter. Then, those sorted cells were cultured in the presence of exogenous erythropoietin and stem cell factor. They highly selectively developed into erythroid lineages including enucleated red blood cells. Sequential FACS analysis using the antibodies against transferrin receptor CD71 and erythroid specific antigen Ter119 in combination with DNA staining dye Hoechst 33342 demonstrated that ES / iPS cell-derived erythropoiesis in our system follow the normal erythroid developmental pathway occurred in vivo. RT-PCR and Western blot analyses proved the expression of heme biosynthesis enzymes on the produced erythrocytes. Finally, the oxygen dissociation curve showed that ES / iPS cell-derived erythroid cells are functionally virtually equivalent to natural red blood cells as oxygen carriers. Taken together, our system can present the effective methods of investigating the mechanisms of normal erythropoiesis and the deficits in syndromes with disrupted red blood cell production. Disclosures: No relevant conflicts of interest to declare.

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Inducible Gata1 Suppression As a Novel Strategy to Expand Physiologic Megakaryocyte Production from Embryonic Stem Cells

Blood ◽

10.1182/blood.v124.21.3846.3846 ◽

2014 ◽

Vol 124 (21) ◽

pp. 3846-3846

Author(s):

Ji-Yoon Noh ◽

Shilpa Gandre-Babbe ◽

Yuhuan Wang ◽

Vincent Hayes ◽

Yu Yao ◽

...

Keyword(s):

Transcription Factor ◽

Conflicts Of Interest ◽

Fetal Liver ◽

Es Cells ◽

Embryonic Stem ◽

Hematopoietic Progenitors ◽

Erythroid Progenitors ◽

Transfusion Therapy ◽

Ips Cell

Abstract Embryonic stem (ES) and induced pluripotent stem (iPS) cells represent potential sources of megakaryocytes and platelets for transfusion therapy. However, most current ES/iPS cell differentiation protocols are limited by low yields of hematopoietic progeny, including platelet-releasing megakaryocytes. Mutations in the mouse and human genes encoding transcription factor GATA1 cause accumulation of proliferating, developmentally arrested megakaryocytes. Previously, we reported that in vitro differentiation of Gata1-null murine ES cells generated self-renewing hematopoietic progenitors termed G1ME cells that differentiated into erythroblasts and megakaryocytes upon restoration of Gata1 cDNA by retroviral transfer. However, terminal maturation of Gata1-rescued megakaryocytes was aberrant with immature morphology and no proplatelet formation, presumably due to non-physiological expression of GATA1. We now engineered wild type (WT) murine ES cells that express doxycycline (dox)-regulated Gata1 short hairpin (sh) RNAs to develop a strategy for Gata1-blockade that upon its release, restores physiologic GATA1 expression during megakaryopoiesis. In vitro hematopoietic differentiation of control scramble shRNA-expressing ES cells with dox and thrombopoietin (TPO) produced megakaryocytes that underwent senescence after 7 days. Under similar differentiation conditions, Gata1 shRNA-expressing ES cells produced immature hematopoietic progenitors, termed G1ME2 cells, which replicated continuously for more than 40 days, resulting in ~1013-fold expansion (N=4 separate experiments). Upon dox withdrawal with multi-lineage cytokines present (EPO, TPO, SCF, GMCSF and IL3), endogenous GATA1 expression was restored to G1ME2 cells followed by differentiation into erythroblasts and megakaryocytes, but no myeloid cells. In clonal methylcellulose assays, dox-deprived G1ME2 cells produced a mixture of erythroid, megakaryocytic and erythro-megakaryocytic colonies. In liquid culture with TPO alone, dox-deprived G1ME2 cells formed mature megakaryocytes in 5-6 days, as determined by morphology, ultrastructure, acetylcholinesterase staining, upregulated megakaryocytic gene expression (Vwf, Pf4, Gp1ba, Selp, Ppbp), CD42b surface expression, increased DNA ploidy and proplatelet production. Compared to G1ME cells rescued with Gata1 cDNA retrovirus, dox-deprived G1ME2 cells exhibited more robust megakaryocytic maturation, similar to that of megakaryocytes produced from cultured fetal liver. Importantly, G1ME2 cell-derived megakaryocytes generated proplatelets in vitro and functional platelets in vivo (~40 platelets/megakaryocyte with a circulating half life of 5-6 hours). These platelets were actively incorporated into growing arteriolar thrombi at sites of laser injury and subsequently expressed the platelet activation marker p-selectin (N=3-4 separate experiments). Our findings indicate that precise timing and magnitude of a transcription factor is required for proper terminal hematopoiesis. We illustrate this principle using a novel, readily reproducible strategy to expand ES cell-derived megakaryocyte-erythroid progenitors and direct their differentiation into megakaryocytes and then into functional platelets in clinically relevant numbers. Disclosures No relevant conflicts of interest to declare.

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MODELING GENETIC Diseases through Reprogramming of HUMAN Amniotic Liquid Derived CELLS

Blood ◽

10.1182/blood.v116.21.4789.4789 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4789-4789

Author(s):

Noufissa Oudrhiri ◽

Frank Yates ◽

Olivier Feraud ◽

Emilie Gobbo ◽

Cecile BAS ◽

...

Keyword(s):

Stem Cells ◽

Gene Transfer ◽

Cell Lines ◽

Human Embryonic Stem Cells ◽

Sickle Cell Anemia ◽

Genetic Diseases ◽

Embryonic Stem ◽

Ips Cells ◽

Ips Cell

Abstract Abstract 4789 Pluripotency and self-renewal, two key characteristics of induced pluripotent stem cells (IPS), make these cells ideally suited for modeling diseases in vitro and generating biological resources usable for drug screening and cell therapy. However, the reprogramming efficiency of somatic cells greatly varies according to the cell type, to the in vitro proliferation index, the number of passages and the age of the donor. Human amniotic liquid-derived cells (hALDC), collected during amniocentesis for the prenatal diagnosis of genetic diseases, represent an abundant source of primary cells. In preliminary experiments we have shown that hALDC expressed endogenous Oct4 and Sox2 proteins suggesting that could be readily amenable to reprogramming. To this end, we have used two strategies using either hALDC or neonatal fibroblasts: (1) lentivirus mediated gene transfer of OCT4, SOX2, LIN28, NANOG, (2) retroviruses mediated gene transfer of OCT4, SOX2, CMYC, KLF4 and (3) lentiviral transfer of OCT4, SOX2. hALDC transduced by these viruses were placed on MEF and b-FGF (10 ng/ml) with daily medium changes. One to three weeks after infection, typical human ES-like colonies could be picked up for expansion before being characterized. HALDC show an increased reprogramming potential with the [OCT4, SOX2, LIN28, NANOG] and [OCT4, SOX2] cocktails, when compared to reprogramming of neonatal fibroblasts. Twelve hALDC-derived-IPS cells were obtained from 12 different samples of amniotic fluid. All hALDC-IPS cell lines maintained a normal karyotype in culture and displayed the morphology and characteristics of human embryonic stem cells, including the surface expression of Tra-160, SSEA-3, SSEA-4, HESCA-1 and alkaline phosphatase, and formed multi-lineaged teratomas upon injection to NOD-SCID mice. Gene expression profiles of the IPS cell lines reveal a high correlation coefficient between hALDC-iPS cells and human embryonic stem cells, and a low correlation between hALDC-iPS and hALDC. When compared to hES cells H1, H9 and Cl01, these cell lines generated hematopoiesis with a variable efficiency in vitro. Amongst the hALDC-IPS cell lines generated by our laboratory (http://www.hescreg.eu/) four lines carry an inherited trisomy of chromosome 21, and three lines carry the homozygous “S” mutation in the beta-globin gene of sickle-cell anemia. All hALDC-IPS cell are currently banked at the Human Pluripotent Stem Cell Core Facility, France. In conclusion, hALDC can be rapidly and efficiently reprogrammed to pluripotency with a limited number of transgenes. Moreover, hALDC-IPS cell lines derived from patients can be used to modelize in vitro the phenotypic features of monogenic diseases such as sickle cell anemia or more complex, multifactorial disorders such as Down's syndrom. The ability to generate hematopoietic differentiation from these cell lines will facilitate the modelling of these hematopoietic disorders. Disclosures: No relevant conflicts of interest to declare.

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Human induced pluripotent stem cells are capable of B-cell lymphopoiesis

Blood ◽

10.1182/blood-2010-08-299941 ◽

2011 ◽

Vol 117 (15) ◽

pp. 4008-4011 ◽

Cited By ~ 50

Author(s):

Lee Carpenter ◽

Ram Malladi ◽

Cheng-Tao Yang ◽

Anna French ◽

Katherine J. Pilkington ◽

...

Keyword(s):

Stem Cells ◽

B Cell ◽

Embryonic Stem ◽

Ips Cells ◽

Ips Cell ◽

Lymphoid Lineage ◽

Human Ips Cells ◽

Induced Pluripotent ◽

First Time ◽

Unique Potential

Abstract Induced pluripotent stem (iPS) cells offer a unique potential for understanding the molecular basis of disease and development. Here we have generated several human iPS cell lines, and we describe their pluripotent phenotype and ability to differentiate into erythroid cells, monocytes, and endothelial cells. More significantly, however, when these iPS cells were differentiated under conditions that promote lympho-hematopoiesis from human embryonic stem cells, we observed the formation of pre-B cells. These cells were CD45+CD19+CD10+ and were positive for transcripts Pax5, IL7αR, λ-like, and VpreB receptor. Although they were negative for surface IgM and CD5 expression, iPS-derived CD45+CD19+ cells also exhibited multiple genomic D-JH rearrangements, which supports a pre–B-cell identity. We therefore have been able to demonstrate, for the first time, that human iPS cells are able to undergo hematopoiesis that contributes to the B-cell lymphoid lineage.

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Human-induced pluripotent stem cells from blood cells of healthy donors and patients with acquired blood disorders

Blood ◽

10.1182/blood-2009-04-217406 ◽

2009 ◽

Vol 114 (27) ◽

pp. 5473-5480 ◽

Cited By ~ 262

Author(s):

Zhaohui Ye ◽

Huichun Zhan ◽

Prashant Mali ◽

Sarah Dowey ◽

Donna M. Williams ◽

...

Keyword(s):

Stem Cells ◽

Cell Lines ◽

Blood Cells ◽

Ips Cells ◽

Patient Specific ◽

Hematopoietic Differentiation ◽

Ips Cell ◽

Healthy Donors ◽

Cd34 Cells ◽

Induced Pluripotent

Abstract Human induced pluripotent stem (iPS) cells derived from somatic cells hold promise to develop novel patient-specific cell therapies and research models for inherited and acquired diseases. We and others previously reprogrammed human adherent cells, such as postnatal fibroblasts to iPS cells, which resemble adherent embryonic stem cells. Here we report derivation of iPS cells from postnatal human blood cells and the potential of these pluripotent cells for disease modeling. Multiple human iPS cell lines were generated from previously frozen cord blood or adult CD34+ cells of healthy donors, and could be redirected to hematopoietic differentiation. Multiple iPS cell lines were also generated from peripheral blood CD34+ cells of 2 patients with myeloproliferative disorders (MPDs) who acquired the JAK2-V617F somatic mutation in their blood cells. The MPD-derived iPS cells containing the mutation appeared normal in phenotypes, karyotype, and pluripotency. After directed hematopoietic differentiation, the MPD-iPS cell-derived hematopoietic progenitor (CD34+CD45+) cells showed the increased erythropoiesis and gene expression of specific genes, recapitulating features of the primary CD34+ cells of the corresponding patient from whom the iPS cells were derived. These iPS cells provide a renewable cell source and a prospective hematopoiesis model for investigating MPD pathogenesis.

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Human Umbilical Cord Blood Derived IPS Cells as a Source of Hematopoietic Progenitors Cells

Blood ◽

10.1182/blood.v116.21.4790.4790 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4790-4790

Author(s):

Roksana Moraghebi ◽

Roger Emanuel Rönn ◽

Aaron Parker ◽

Margaret Lutz ◽

Travis Berggren ◽

...

Keyword(s):

Cord Blood ◽

Cell Lines ◽

Umbilical Cord ◽

Umbilical Cord Blood ◽

Ips Cells ◽

Cell Fraction ◽

Human Umbilical Cord Blood ◽

Human Umbilical Cord ◽

Hematopoietic Progenitors ◽

Ips Cell

Abstract Abstract 4790 The ability to generate hematopoietic stem cells (HSCs) from an unlimited source of cells, such as from patient derived induced pluripotent stem (iPS) cells, would enable the generation of an unlimited supply of HLA matched transplantable HSCs for therapeutic purposes. Umbilical cord blood is an ideal source of fetal/neonatal cellular material for iPS reprogramming due to the proliferative capacity of the cells as well as the reduced exposure of these cells to environmental factors compare to commonly used skin fibroblasts. In addition, it has been proposed that the cellular starting material imparts an epigenetic memory to the iPS cell line that influences lineage predisposition upon its differentiation. This project seeks to evaluate human umbilical cord blood as a starting cell source for generating iPS cells, with the ultimate goal to generate transplantable HSCs. We have isolated, cultured, and characterized an adherent cell fraction from the hemato-endothelial lineage. These cells were found to have an endothelial progenitor phenotype with CD45neg, CD133neg, VE-Cadherinhi, VEGFR2med, CD31hi, CD34hi cell surface markers as determined by FACS and formed tubules in the matrigel tubular assay. The iPS cell lines were generated using a 5-factor cocktail of inducible lentiviral vectors with an efficiency of 0.02%. The iPS cell lines were then evaluated for blood cell lineage differentiation capacity using our state-of-the-art ES/iPS-to-blood differentiation protocol. From the 5 iPS lines we tested, we saw 30 +/− 20% hematopoietic (CD45+) cells in our differentiation cultures. Moreover, the percentage of hematopoietic progenitors (CD45+ CD34+) of the hematopoietic cell fraction was 19.8+/− 0.6%, and also showed the presence of the more primitive CD45+ CD34+ CD38- progenitor fraction. Clonogenic progenitor cell counts determined by methylcellulose colony assay showed 44 +/− 3 colony forming units per 10,000 plated CD45+ cells. This is in the range of colonies obtained from umbilical cord blood mononuclear cell isolates (mean= 35+/− 2). The efficiency of hematopoietic generation for the lines ranged from 8 to 60% CD45+ suggesting that there are significant differences between the lines in terms of the completeness of reprogramming towards the pluripotent state. Further investigation into the epigenetic status of these lines is being performed. These data demonstrate the utility of human umbilical cord blood derived iPS cells for generating and expanding hematopoietic progenitors. This project advances iPS technologies towards treating life threatening hematological malignancies and diseases. Disclosures: No relevant conflicts of interest to declare.

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Re-establishing pluripotency in adult cells derived from breast stromal tissue.

Journal of Clinical Oncology ◽

10.1200/jco.2011.29.27_suppl.227 ◽

2011 ◽

Vol 29 (27_suppl) ◽

pp. 227-227

Author(s):

S. M. L. Lim ◽

I. Aksoy ◽

K. G. C. Lim ◽

J. Karuppasamy ◽

U. Divakar ◽

...

Keyword(s):

Cell Biology ◽

Breast Tissue ◽

Ectopic Expression ◽

Embryonic Stem ◽

Ips Cells ◽

Dermal Fibroblasts ◽

Patient Specific ◽

Stromal Tissue ◽

Induced Pluripotent

227 Background: Recent advances in pluripotent stem cell biology offer patient-specific disease models to investigate in vitro mechanisms of tumorigenesis. Induced pluripotent stem (iPS) cells were originally derived by reprogramming of human dermal fibroblasts through ectopic expression of pluripotency–associated transcription factors. A limitation to the use of dermal fibroblasts as the starting cell type for reprogramming is that it usually takes weeks to expand cells from a single biopsy, and the efficiency of the process is very low. In contrast, a large number of adipose-derived mesenchymal stromal cells (Ad-MSCs) can be easily obtained from the stroma of human breast tissue, without the time-consuming steps of cell expansion. Here we investigated the ability to induce pluripotency in committed, Ad-MSCs derived from the stroma of breast tissue. Methods: The aim of this study is to investigate the potential of using Ad-MSCs derived from surgically discarded breast stromal tissue to generate human iPS. Discarded tissue during surgical procedures was processed in vitro and Ad-MSCs were derived. These Ad-MSCs were then used to generate iPS cells by ectopic expression of “Yamanaka’s cocktail” containing OCT4, SOX2, KLF4 and c-MYC. Results: The success rate in generating iPS cells from human Ad-MSCs derived from breast stromal tissue is very high compared to the use of dermal fibroblasts. In our study, almost all human Ad-MSC cell lines can be reprogrammed into iPS cells, which share the same characteristics as skin fibroblast-derived iPS cells and human embryonic stem cells in their morphology, gene expression profile and differentiation capacities. Conclusions: We are now optimizing this approach and making it more clinically relevant by adopting an integration-free method to deliver the reprogramming factors. The successful reprogramming of breast stromal-derived Ad-MSCs into iPS cells may provide a valuable source of patient-specific iPS cells to study the mechanism of tumorigenesis in patients with breast cancer.

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Induced Pluripotent Stem Cells in Cardiovascular Medicine

Stem Cells International ◽

10.4061/2011/348960 ◽

2011 ◽

Vol 2011 ◽

pp. 1-7 ◽

Cited By ~ 15

Author(s):

Toru Egashira ◽

Shinsuke Yuasa ◽

Keiichi Fukuda

Keyword(s):

Regenerative Medicine ◽

Embryonic Stem ◽

Stem Cell Differentiation ◽

Ips Cells ◽

Cardiovascular Research ◽

Ips Cell ◽

Cell Technology ◽

The Future ◽

Human Ips Cells ◽

Induced Pluripotent

Induced pluripotent stem (iPS) cells are generated by reprogramming human somatic cells through the forced expression of several embryonic stem (ES) cell-specific transcription factors. The potential of iPS cells is having a significant impact on regenerative medicine, with the promise of infinite self-renewal, differentiation into multiple cell types, and no problems concerning ethics or immunological rejection. Human iPS cells are currently generated by transgene introduction principally through viral vectors, which integrate into host genomes, although the associated risk of tumorigenesis is driving research into nonintegration methods. Techniques for pluripotent stem cell differentiation and purification to yield cardiomyocytes are also advancing constantly. Although there remain some unsolved problems, cardiomyocyte transplantation may be a reality in the future. After those problems will be solved, applications of human iPS cells in human cardiovascular regenerative medicine will be envisaged for the future. Furthermore, iPS cell technology has generated new human disease models using disease-specific cells. This paper summarizes the progress of iPS cell technology in cardiovascular research.

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Research Progress and Application Prospect of IPS Cells

Gene Science and Engineering ◽

10.18063/gse.v1i1.526 ◽

2018 ◽

Vol 1 (1) ◽

Author(s):

Ceng Yiwu

Keyword(s):

Stem Cells ◽

Es Cells ◽

Embryonic Stem ◽

Donor Cell ◽

Ips Cells ◽

New Drugs ◽

Theoretical Research ◽

Research Progress ◽

Ips Cell

Differentiated somatic cells can be reprogrammed into induced pluripotent stem cells (iPS cells) by introducingspecific transcription factors. This technique avoids immune rejection and ethical problems in stem cell research.A great revolution in the fi eld of science. As with embryonic stem cells (ES cells), iPS cells are able to self-renewand maintain undiff erentiated state. In vitro, iPS cells can be induced to diff erentiate into a variety of mature cells,therefore, iPS cells in theoretical research and clinical applications are extremely valuable. IPS cell diff erentiationand transplantation in the treatment of blood diseases have a great use, iPS cells can treat nervous system diseases,to provide in vitro disease model, to study the mechanism of disease formation, screening new drugs and thedevelopment of new to provide a new treatment The The use of iPS cells as a nuclear donor cell, with the appropriatereceptor cells after fusion can be directly obtained transgenic animals. Not only can improve the genetic nature ofanimals, but also can break the boundaries of species and get the new animal traits that cannot achieve by usingtraditional mating methods. The research of iPS cells has been widely concerned, and it is the research hotspot in cellbiology and molecular biology. In this paper, the defi nition of iPS cells, the acquisition of iPS cells, the history ofdevelopment, the signifi cance of research, the progress of research, the application of iPS cells, and the problems ofiPS cells were reviewed.

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Approach to Neurotoxicity using Human iPSC Neurons: Consortium for Safety Assessment using Human iPS Cells

Current Pharmaceutical Biotechnology ◽

10.2174/1389201020666191129103730 ◽

2020 ◽

Vol 21 (9) ◽

pp. 780-786

Author(s):

Takafumi Shirakawa ◽

Ikuro Suzuki

Keyword(s):

Cell Biology ◽

Safety Assessment ◽

Neuronal Cell ◽

Electrode Array ◽

Ips Cells ◽

Current Status ◽

Ips Cell ◽

Human Ips Cells

Neurotoxicity, as well as cardiotoxicity and hepatotoxicity, resulting from administration of a test article is considered a major adverse effect both pre-clinically and clinically. Among the different types of neurotoxicity occurring during the drug development process, seizure is one of the most serious one. Seizure occurrence is usually assessed using in vivo animal models, the Functional Observational Battery, the Irwin test or electroencephalograms. In in vitro studies, a number of assessments can be performed using animal organs/cells. Interestingly, recent developments in stem cell biology, especially the development of Human-Induced Pluripotent Stem (iPS) cells, are enabling the assessment of neurotoxicity in human iPS cell-derived neurons. Further, a Multi-Electrode Array (MEA) using rodent neurons is a useful tool for identifying seizure-inducing compounds. The Consortium for Safety Assessment using Human iPS Cells (CSAHi; http://csahi.org/en/) was established in 2013 by the Japan Pharmaceutical Manufacturers Association (JPMA) to verify the application of human iPS cell-derived neuronal cells to drug safety evaluation. The Neuro Team of CSAHi has been attempting to evaluate the seizure risk of compounds using the MEA platform. Here, we review the current status of neurotoxicity and recent work, including problems related to the use of the MEA assay with human iPS neuronal cell-derived neurons, and future developments.

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