Embryoid body

The ES cells were encapsulated in the PMBV/PVA hydrogel by the same method used for the L929 cells. In general, ES cells form a cell aggregate called an embryoid body in suspension culture. However, it was observed that the encapsulated ES cells in the hydrogel did not form any embryoid body for 72 h. 

Human embryonic stem cells / Culture as floating aggregratesN. (embryoid bodies), forming / neuroepithelial cells s Culture to form midbrain dopamine neurons ... 

ES cells aggregated into embryoid bodies and propagated in growth factors, including platelet-derived growth factor, differentiate rapidly to include CNS glial cells. 

Karp JM, Yeh J, Eng G, Fukuda J, Blumling J, Suit KY, Cheng J, Mahdavi A, Borenstein J, Langer R, Khademhosseini A (2007) Controlling size, shape and homogeneity of embryoid bodies using poly(ethylene glycol) microwells. Lab Chip 7 786-794. 

Confrontation cultures between tumor spheroids and solid tissues 3-D from 3-D Insight into biological processes and involved molecules, mimic of in vivo microenvironment via invasion into embryoid bodies or explanted tissues Histological analysis and quantification necessary, low throughput (133, 134)... 

Wartenberg M, Donmez F, Ling FC et al (2001) Tumor-induced angiogenesis studied in confrontation cultures of multicellular tumor spheroids and embryoid bodies grown from pluripotent embryonic stem cells. FASEB J 15 995-1005... 

Itskovitz-Eldor J, Schuldiner M, Karsenti D, Eden A, Yanuka O, Amit M, Soreq H, Benvenisty N. Differentiation of human embryonic stem cells into embryoid bodies compromising the three embryonic germ layers. Mo/MeJ 2000 6 88-95. 

The embryonic stem cell test is an animal-free alternative test method for developmental toxicity. Mouse embryonic stem cells are cultured in a hanging drop method to form embryoid bodies. These embryoid bodies, when plated on tissue culture dishes, differentiate to form contracting myocardial cell foci within 10 days. Inhibition of cardiomyocyte differentiation by test compounds serves as the end point of the assay, as monitored by cormting contracting muscle foci under the microscope. 

Fig. 2. The embryonic stem cell test. Droplets with 750 ES cells per 20 l complete medium are pipetted on the inner side of a cover lid of a 94 x 16 mm bacterial Petri dish (a). 56 droplets are cultured in a Flanging drop method.The lid is placed on a Petri dish, containing 5 ml of PBS (b).The cells will form Embryoid bodies (EB) (c) by proliferation and clustering. After 3 days the EB are transferred to a Petri dish containing 5 ml suspension medium (d). The EB are cultured for 2 days and then transferred to a 24-well plate (e) where they will further differentiate into contracting cardiomyocytes. The scoring is pertormed at day 10 by examining the EB under a light microscope (f).

Fig. 3. Embryoid bodies at day 3 (a). Embryoid bodies at day 5 (b). Differentiated ceiis into contracting myocardiai ceiis at day 10 (c). Unstained, iight microscopy, magnification 4x.

Stary M, Schneider M, Sheikh SP, Weitzer G. 2006. Parietal endoderm secreted S100A4 promotes early cardiomyogenesis in embryoid bodies. Biochem Biophys Res Commun 343(2) 555-563. 

Daley GQ (2003), From embryos to embryoid bodies generating blood from embryonic stem cells, Ann. Acad. Sci. 996 122-131. 

When plated onto untreated dished F9 cells proliferate rapidly and form clumps of necrotic spheres by 4-8 days. In the presence of 5x10-8M retinoic acid (supplied from a stock of 1 mg/ml in DMSO) proliferation and aggregation occurs but, by about 5 days, embryoid bodies are formed which remain stable for more than 25 days (Adamson and Grover, 1983). It is in the early stages that differentiated functions are first expressed and alpha foetoprotein can be detected in the outer cells of the embryoid bodies at 6-8 days depending on the initial seeding density. There is increased production of laminin at 2 days. 

As long as embryonic stem cells in culture are grown under certain conditions, they can remain undifferentiated (unspecialized). But if cells are allowed to clump together to form embryoid bodies they begin to differentiate spontaneously into specific cell types (muscle cells, nerve cells, etc.). To generate cultures of specific types of differentiated cells, various growth factors are used in the culture media [45],... 

GNE UDP-GlcNAc 2-epimerase/ManNAc 6-kinase GDP guanidine diphosphate hEBD human embryoid body-derived... 

All of these methods follow the typical protocol for embryoid body generation as described below. 

Kurosawa H (2007) Methods for inducing embryoid body formation in vitro differentiation system of embryonic stem cells. J Biosci Bioeng 103(5) 389-398... 

Improved human embryonic stem cell embryoid body homogeneity and cardiomyocyte differentiation from a novel V-96 plate... 

Dang SM, Kyba M, Perlingeiro R, Daley GQ, Zandstra PW (2002) Efficiency of embryoid body formation and hematopoietic development from embryonic stem cells in different culture systems. Biotechnol Bioeng 78(4) 442 53... 

Koike M, Kurosawa H, Amano Y (2005) A round-bottom 96-well polystyrene plate coated with 2-methacryloyloxyethyl phos-phorylcholine as an effective tool for embryoid body formation. Cytotechnology 47(1-3) 3-10... 

Ng ES, Davis RP, Azzola L, Stanley EG, Elefanty AG (2005) Forced aggregation of defined numbers of human embryonic stem cells into embryoid bodies fosters robust, reproducible hematopoietic differentiation. Blood 106(5) 1601-1603... 

The EST has been developed with the aim to exploit the characteristics and differentiation potential of mouse embryonic stem cells (ES cells), established from the early embryo in 1981 [4, 5], ES cells are cultured in suspension to induce the formation of embryoid bodies, and afterwards they are transferred in 24-well dishes to allow attachment and differentiation in contracting cardiomyocytes. The toxicological endpoint is the inhibition of cardiac differentiation. In parallel a cytotoxicity test is performed on undifferentiated ES cells and a control somatic (fibroblast) cell line (3T3). The concentrations of testing chemicals that induce 50 % of differentiation inhibition (ID50) and 50 % cytotoxicity (IC50) in ES cells and 3T3 cells are inserted in a validated prediction model to classify the test chemical as non-embryotoxic, moderate, or strong embryotoxic [2, 6, 7], The validation of the method has been... 

Embryoid bodies Neuro-ectoderm progenitor cells Neural Rosettes NPCs to mature neurons 14 days 6 days 10 days 3 days expression (Affymetrix Chip Arrays) mannitol ... 

Bhattacharya B, Cai J, Luo Y, Miura T, Mejido J, Brimble SN, Zeng X, Schulz TC, Rao MS, Puri RK (2005) Comparison of the gene expression profile of undifferentiated human embryonic stem cell lines and differentiating embryoid bodies. BMC Dev Biol 5 22, doi 1471-213X-5-22... 

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