Protocols For Differentiation Of hESCs Research Articles

Differentiation of Human Embryonic Stem Cells into Neuron, Cholinergic, and Glial Cells.

Human embryonic stem cells (hESCs) are pluripotent cells, capable of differentiation into different cellular lineages given the opportunity. Derived from the inner cell mass of blastocysts in early embryonic development, the cell self-renewal ability makes them a great tool for regenerative medicine, and there are different protocols available for maintaining hESCs in their undifferentiated state. In addition, protocols for differentiation into functional human neural stem cells (hNSCs), which have the potential for further differentiation into various neural cell types, are available. However, many protocols are time-consuming and complex and do not always fit for purpose. In this study, we carefully combined, optimized, and developed protocols for differentiation of hESCs into adherent monolayer hNSCs over a short period of time, with the possibility of both expansion and freezing. Moreover, the method details further differentiation into neurons, cholinergic neurons, and glial cells in a simple, single step by step protocol. We performed immunocytochemistry, qPCR, and electrophysiology to examine the expression profile and characteristics of the cells to verify cell lineage. Using presented protocols, the creation of neuronal cultures, cholinergic neurons, and a mixed culture of astrocytes and oligodendrocytes can be completed within a three-week time period.

Single-Cell Transcriptome Profiling of Mouse and hESC-Derived Pancreatic Progenitors.

SummaryHuman embryonic stem cells (hESCs) are a potential unlimited source of insulin-producing β cells for diabetes treatment. A greater understanding of how β cells form during embryonic development will improve current hESC differentiation protocols. All pancreatic endocrine cells, including β cells, are derived from Neurog3-expressing endocrine progenitors. This study characterizes the single-cell transcriptomes of 6,905 mouse embryonic day (E) 15.5 and 6,626 E18.5 pancreatic cells isolated from Neurog3-Cre; Rosa26mT/mG embryos, allowing for enrichment of endocrine progenitors (yellow; tdTomato + EGFP) and endocrine cells (green; EGFP). Using a NEUROG3-2A-eGFP CyT49 hESC reporter line (N5-5), 4,462 hESC-derived GFP+ cells were sequenced. Differential expression analysis revealed enrichment of markers that are consistent with progenitor, endocrine, or previously undescribed cell-state populations. This study characterizes the single-cell transcriptomes of mouse and hESC-derived endocrine progenitors and serves as a resource (https://lynnlab.shinyapps.io/embryonic_pancreas) for improving the formation of functional β-like cells from hESCs.

Abstract 461: Prospective Isolation of Heart Field Specific Cardiomyocytes from Differentiating Human Embryonic Stem Cells

Cardiovascular disease (CVD) is the leading cause of death worldwide. Human embryonic stem cell (hESC) derived cardiovascular progenitor cells (CPCs) or cardiomyocytes (CMs) represent a promising candidate for cell-based therapies to treat CVD. Following a myocardial infarction there is extensive CM death and damage primarily localized to the left ventricle of the heart, which is predominantly derived from first heart field (FHF) CPCs during development. This is important in future developmental and regenerative therapy studies since heart field specific cardiac cells will be desired. Current hESC differentiation protocols as well as the use of cardiac-specific reporter lines, yield a mixture of cardiac cells without the ability to isolate heart field specific cardiac progenitors and their associated progeny. Here we generated and characterized a FHF specific TBX5- TdTomato/W hESC reporter line to show that TBX5 + cells represent an enriched population of FHF CPCs that can give rise to CMs, endothelial and smooth muscle cells in vitro . Transplantation of hESC-derived TBX5 + and TBX5 - CPCs into the injured left ventricle of mice showed that these cells were able to survive and predominantly gave rise to CMs without functional integration into the host myocardium. Furthermore, RNA-sequencing analysis of hESC-derived cardiac cells at different stages of development suggested that while TBX5 expression leads to an enrichment of FHF- derived CMs, TBX5 - cells also generate cardiac cells that resemble second heart field (SHF) CMs at the transcriptional level. To enable prospective isolation of FHF and SHF CMs we generated a double transgenic hESC reporter line TBX5 TdTomato/W /NKX2-5 eGFP/W . Using immunostaining, qPCR and electrophysiological studies we were able to confirm the isolation of FHF and SHF specific CMs from differentiating hESCs. Finally, we show that using the novel surface marker, CORIN, we can isolate FHF CMs without the use of genetic reporters. Our studies provide valuable information and resources on the production of heart field specific CMs from hESCs for cell-based therapies to treat CVD.

Generation of reporter hESCs by targeting EGFP at the CD144 locus to facilitate the endothelial differentiation.

Reporter embryonic stem cell (ESC) lines with tissue-specific reporter genes may contribute to optimizing the differentiation conditions in vitro as well as trafficking transplanted cells in vivo. To optimize and monitor endothelial cell (EC) differentiation specifically, here we targeted the enhanced green fluorescent protein (EGFP) reporter gene at the junction of 5'UTR and exon2 of the endothelial specific marker gene CD144 using TALENs in human ESCs (H9) to generate a EGFP-CD144-reporter ESC line. The reporter cells expressed EGFP and CD144 increasingly and specifically without unexpected effects during the EC differentiation. The EC differentiation protocol was optimized and applied to EC differentiation from hiPSCs, resulting in an efficient and simplified endothelial differentiation approach. Here we created our own optimized and robust protocol for EC differentiation of hESCs and hiPSCs by generating the lineage-specific site-specific integration reporter cell lines, showing great potential to be applied in the fields such as trafficking gene and cell fate in vivo in preclinical animal models.

Differentiation of Human Embryonic Stem Cells to Endothelial Progenitor Cells on Laminins in Defined and Xeno-free Systems.

SummaryA major hurdle for in vitro culturing of primary endothelial cells (ECs) is that they readily dedifferentiate, hampering their use for therapeutic applications. Human embryonic stem cells (hESCs) may provide an unlimited cell source; however, most current protocols deriving endothelial progenitor cells (EPCs) from hESCs use direct differentiation approaches albeit on undefined matrices, yet final yields are insufficient. We developed a method to culture monolayer hESCs on stem cell niche laminin (LN) LN511 or LN521 matrix. Here, we report a chemically defined, xeno-free protocol for differentiation of hESCs to EPCs using LN521 as the main culture substrate. We were able to generate ∼95% functional EPCs defined as VEGFR2+CD34+CD31+VE-Cadherin+. RNA-sequencing analyses of hESCs, EPCs, and primary human umbilical vein endothelial cells showed differentiation-related EC expression signatures, regarding basement membrane composition, cell-matrix interactions, and changes in endothelial lineage markers. Our results may facilitate production of stable ECs for the treatment of vascular diseases and in vitro cell modeling.

Pancreas development in humans

We highlight some of the major recent advances in characterizing human pancreas development and endocrine cell differentiation. Extensive research efforts have helped to define crucial events in the mouse pancreas organogenesis. Information gained from these studies was used to develop human embryonic stem cell (hESC) differentiation protocols with the goal of generating functional glucose-responsive, insulin-producing human β-cells. In spite of remarkable progress in hESC differentiation, current protocols based on mouse developmental biology can produce human β-cells only in vivo. New differentiation markers and recently generated reagents may provide an unprecedented opportunity to develop a high-density expression map of human fetal pancreas and pancreatic islets that could serve as a reference point for in vitro hESC differentiation. Integrating an increased knowledge of human pancreas development into hESC differentiation protocols has the potential to greatly advance our ability to generate functional insulin-producing cells for β-cell replacement therapy.

Driven Hematopoietic Differentiation of Embryonic Stem Cells: Epigenetic Perspectives

Hematopoietic progenitors derived from human embryonic stem cells (hESCs) present both a potential cell source for cell-replacement therapies and an in vitro model for hematopoietic stem cell (HSC) development. Current protocols for the hematopoietic differentiation of hESCs suffer from low efficiency and functional defects in the derived HSCs. Epigenetic mechanisms of HSC development should be addressed to overcome these imperfections. The focus of this review is to summarize the knowledge on the epigenetic regulation of pluripotency and lineage-specific genes with the emphasis on the hematopoietic cell lineage. The potential utilization of this knowledge to improve the generation of HSCs for clinical application is also discussed.

Enrichment and Purging of Human Embryonic Stem Cells by Detection of Cell Surface Antigens Using the Monoclonal Antibodies TG30 and GCTM-2

Human embryonic stem cells (hESC) can self-renew indefinitely in vitro, and with the appropriate cues can be induced to differentiate into potentially all somatic cell lineages. Differentiated hESC derivatives can potentially be used in transplantation therapies to treat a variety of cell-degenerative diseases. However, hESC differentiation protocols usually yield a mixture of differentiated target and off-target cell types as well as residual undifferentiated cells. For the translation of differentiated hESC-derivatives from the laboratory to the clinic, it is important to be able to discriminate between undifferentiated (pluripotent) and differentiated cells, and generate methods to separate these populations. Safe application of hESC-derived somatic cell types can only be accomplished with pluripotent stem cell-free populations, as residual hESCs could induce tumors known as teratomas following transplantation. Towards this end, here we describe a methodology to detect pluripotency associated cell surface antigens with the monoclonal antibodies TG30 (CD9) and GCTM-2 via fluorescence activated cell sorting (FACS) for the identification of pluripotent TG30Hi-GCTM-2Hi hESCs using positive selection. Using negative selection with our TG30/GCTM-2 FACS methodology, we were able to detect and purge undifferentiated hESCs in populations undergoing very early-stage differentiation (TG30Neg-GCTM-2Neg). In a further study, pluripotent stem cell-free samples of differentiated TG30Neg-GCTM-2Neg cells selected using our TG30/GCTM-2 FACS protocol did not form teratomas once transplanted into immune-compromised mice, supporting the robustness of our protocol. On the other hand, TG30/GCTM-2 FACS-mediated consecutive passaging of enriched pluripotent TG30Hi-GCTM-2Hi hESCs did not affect their ability to self-renew in vitro or their intrinsic pluripotency. Therefore, the characteristics of our TG30/GCTM-2 FACS methodology provide a sensitive assay to obtain highly enriched populations of hPSC as inputs for differentiation assays and to rid potentially tumorigenic (or residual) hESC from derivative cell populations.

Enrichment and Purging of Human Embryonic Stem Cells by Detection of Cell Surface Antigens Using the Monoclonal Antibodies TG30 and GCTM-2

Human embryonic stem cells (hESC) can self-renew indefinitely in vitro, and with the appropriate cues can be induced to differentiate into potentially all somatic cell lineages. Differentiated hESC derivatives can potentially be used in transplantation therapies to treat a variety of cell-degenerative diseases. However, hESC differentiation protocols usually yield a mixture of differentiated target and off-target cell types as well as residual undifferentiated cells. For the translation of differentiated hESC-derivatives from the laboratory to the clinic, it is important to be able to discriminate between undifferentiated (pluripotent) and differentiated cells, and generate methods to separate these populations. Safe application of hESC-derived somatic cell types can only be accomplished with pluripotent stem cell-free populations, as residual hESCs could induce tumors known as teratomas following transplantation. Towards this end, here we describe a methodology to detect pluripotency associated cell surface antigens with the monoclonal antibodies TG30 (CD9) and GCTM-2 via fluorescence activated cell sorting (FACS) for the identification of pluripotent TG30Hi-GCTM-2Hi hESCs using positive selection. Using negative selection with our TG30/GCTM-2 FACS methodology, we were able to detect and purge undifferentiated hESCs in populations undergoing very early-stage differentiation (TG30Neg-GCTM-2Neg). In a further study, pluripotent stem cell-free samples of differentiated TG30Neg-GCTM-2Neg cells selected using our TG30/GCTM-2 FACS protocol did not form teratomas once transplanted into immune-compromised mice, supporting the robustness of our protocol. On the other hand, TG30/GCTM-2 FACS-mediated consecutive passaging of enriched pluripotent TG30Hi-GCTM-2Hi hESCs did not affect their ability to self-renew in vitro or their intrinsic pluripotency. Therefore, the characteristics of our TG30/GCTM-2 FACS methodology provide a sensitive assay to obtain highly enriched populations of hPSC as inputs for differentiation assays and to rid potentially tumorigenic (or residual) hESC from derivative cell populations.

Initial Cell Seeding Density Influences Pancreatic Endocrine Development During in vitro Differentiation of Human Embryonic Stem Cells

Human embryonic stem cells (hESCs) have the ability to form cells derived from all three germ layers, and as such have received significant attention as a possible source for insulin-secreting pancreatic beta-cells for diabetes treatment. While considerable advances have been made in generating hESC-derived insulin-producing cells, to date in vitro-derived glucose-responsive beta-cells have remained an elusive goal. With the objective of increasing the in vitro formation of pancreatic endocrine cells, we examined the effect of varying initial cell seeding density from 1.3 x 104 cells/cm2 to 5.3 x 104 cells/cm2 followed by a 21-day pancreatic endocrine differentiation protocol. Low density-seeded cells were found to be biased toward the G2/M phases of the cell cycle and failed to efficiently differentiate into SOX17-CXCR4 co-positive definitive endoderm cells leaving increased numbers of OCT4 positive cells in day 4 cultures. Moderate density cultures effectively formed definitive endoderm and progressed to express PDX1 in approximately 20% of the culture. High density cultures contained approximately double the numbers of PDX1 positive pancreatic progenitor cells and also showed increased expression of MNX1, PTF1a, NGN3, ARX, and PAX4 compared to cultures seeded at moderate density. The cultures seeded at high density displayed increased formation of polyhormonal pancreatic endocrine cell populations co-expressing insulin, glucagon and somatostatin. The maturation process giving rise to these endocrine cell populations followed the expected cascade of pancreatic progenitor marker (PDX1 and MNX1) expression, followed by pancreatic endocrine specification marker expression (BRN4, PAX4, ARX, NEUROD1, NKX6.1 and NKX2.2) and then pancreatic hormone expression (insulin, glucagon and somatostatin). Taken together these data suggest that initial cell seeding density plays an important role in both germ layer specification and pancreatic progenitor commitment, which precedes pancreatic endocrine cell formation. This work highlights the need to examine standard culture variables such as seeding density when optimizing hESC differentiation protocols.

Forced aggregation and defined factors allow highly uniform-sized embryoid bodies and functional cardiomyocytes from human embryonic and induced pluripotent stem cells

In vitro human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) can differentiate into functional cardiomyocytes (CMs). Protocols for cardiac differentiation of hESCs and hiPSCs include formation of the three-dimensional cell aggregates called embryoid bodies (EBs). The traditional suspension method for EB formation from clumps of cells results in an EB population heterogeneous in size and shape. In this study we show that forced aggregation of a defined number of single cells on AggreWell plates gives a high number of homogeneous EBs that can be efficiently differentiated into functional CMs by application of defined growth factors in the media. For cardiac differentiation, we used three hESC lines and one hiPSC line. Our contracting EBs and the resulting CMs express cardiac markers, namely myosin heavy chain α and β, cardiac ryanodine receptor/calcium release channel, and cardiac troponin T, shown by real-time polymerase chain reaction and immunocytochemistry. Using Ca(2+) imaging and atomic force microscopy, we demonstrate the functionality of RyR2 to release Ca(2+) from the sarcoplasmic reticulum as well as reliability in contractile and beating properties of hESC-EBs and hiPSC-EBs upon the stimulation or inhibition of the β-adrenergic pathway.

Improved Hepatic Differentiation Strategies for Human Induced Pluripotent Stem Cells

Based on their almost unlimited self-renewal capacity and their ability to differentiate into derivatives of all three germ layers, human induced pluripotent stem cells (hiPSCs) might serve as a preferable source for hepatic transplants in metabolic liver disorders or acute liver failure. Furthermore, the generation of patient specific hiPSCs might facilitate the development of innovative therapeutic strategies by accurately modelling disease in vitro. In our study, we aimed for an efficient hepatic differentiation protocol that is applicable for both human embryonic stem cells (hESCs) and hiPSCs. We attempted to accomplish this goal by using a cytokine and small molecule-based protocol for direct differentiation of hESCs and hiPSCs into hepatic cells. Selecting differentiated hepatic cells was possible using an albumin promoter-driven G418 resistance system. Due to IRES-dependent dTomato reporter expression, we were able to track hepatic differentiated cells and we evaluated the most efficient time frame for G418 selection. The status of hepatic differentiation was determined by qRT-PCR comparing the expression of hepatic markers such as AFP, ALB, SOX17, and HNF4 to standard hepatic cells. Functional analysis of the hepatic phenotype was obtained by measuring secreted albumin levels and by analysis of cytochrome P450 type 1A1 activity (EROD). The percentage of differentiated cells was quantified by FACS analysis. In conclusion, our improved protocol demonstrates that both pluripotent cell sources (hESC and hiPSC) can efficiently be differentiated into mature hepatic cells with functional characteristics similar to those of standard hepatic cell lines such as HepG2.