Shrinky-dink hanging drops: a simple way to form and culture embryoid bodies.
ABSTRACT Embryoid bodies (EB) are aggregates of embryonic stem cells. The most common way of creating these aggregates is the hanging drop method, a laborious approach of pipetting an arbitrary number of cells into well plates. The interactions between the stem cells forced into close proximity of one another promotes the generation of the EBs. Because the media in each of the wells has to be manually exchanged every day, this approach is manually intensive. Moreover, because environmental parameters including cell-cell, cell-soluble factor interactions, pH, and oxygen availability can be functions of EB size, cell populations obtained from traditional hanging drops can vary dramatically even when cultured under identical conditions. Recent studies have indeed shown that the initial number of cells forming the aggregate can have significant effects on stem cell differentiation. We have developed a simple, rapid, and scalable culture method to load pre-defined numbers of cells into microfabricated wells and maintain them for embryoid body development. Finally, these cells are easily accessible for further analysis and experimentation. This method is amenable to any lab and requires no dedicated equipment. We demonstrate this method by creating embryoid bodies using a red fluorescent mouse cell line (129S6B6-F1).
Full-textDOI: · Available from: Jonathan Dusan Pegan, Mar 17, 2014
- SourceAvailable from: Ali Khademhosseini
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- "There are several methods that have been previously used to control aggregate size when forming aggregates. Most common among these is the hanging drop method . However this method does not allow for the production of large numbers of aggregates for mass production. "
ABSTRACT: A major hurdle in the use of exogenous stems cells for therapeutic regeneration of injured myocardium remains the poor survival of implanted cells. To date, the delivery of stem cells into myocardium has largely focused on implantation of cell suspensions. We hypothesize that delivering progenitor cells in an aggregate form would serve to mimic the endogenous state with proper cell-cell contact, and may aid the survival of implanted cells. Microwell methodologies allow for the culture of homogenous 3D cell aggregates, thereby allowing cell-cell contact. In this study, we find that the culture of cardiac progenitor cells in a 3D cell aggregate augments cell survival and protects against cellular toxins and stressors, including hydrogen peroxide and anoxia/reoxygenation induced cell death. Moreover, using a murine model of cardiac ischemia-reperfusion injury, we find that delivery of cardiac progenitor cells in the form of 3D aggregates improved in vivo survival of implanted cells. Collectively, our data support the notion that growth in 3D cellular systems and maintenance of cell-cell contact improves exogenous cell survival following delivery into myocardium. These approaches may serve as a strategy to improve cardiovascular cell-based therapies.PLoS ONE 11/2012; 7(11):e50491. DOI:10.1371/journal.pone.0050491 · 3.23 Impact Factor
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- "Centrifugal force was not required for hEB formation using this media formulation (Figure S5F). Other aggregation hEB formation techniques such as AggreWell (StemCell Technologies)  or ‘Shrinky-dink’ methods did not result in cardiac differentiation  (data not shown). "
ABSTRACT: The production of cardiomyocytes from human induced pluripotent stem cells (hiPSC) holds great promise for patient-specific cardiotoxicity drug testing, disease modeling, and cardiac regeneration. However, existing protocols for the differentiation of hiPSC to the cardiac lineage are inefficient and highly variable. We describe a highly efficient system for differentiation of human embryonic stem cells (hESC) and hiPSC to the cardiac lineage. This system eliminated the variability in cardiac differentiation capacity of a variety of human pluripotent stem cells (hPSC), including hiPSC generated from CD34(+) cord blood using non-viral, non-integrating methods. We systematically and rigorously optimized >45 experimental variables to develop a universal cardiac differentiation system that produced contracting human embryoid bodies (hEB) with an improved efficiency of 94.7±2.4% in an accelerated nine days from four hESC and seven hiPSC lines tested, including hiPSC derived from neonatal CD34(+) cord blood and adult fibroblasts using non-integrating episomal plasmids. This cost-effective differentiation method employed forced aggregation hEB formation in a chemically defined medium, along with staged exposure to physiological (5%) oxygen, and optimized concentrations of mesodermal morphogens BMP4 and FGF2, polyvinyl alcohol, serum, and insulin. The contracting hEB derived using these methods were composed of high percentages (64-89%) of cardiac troponin I(+) cells that displayed ultrastructural properties of functional cardiomyocytes and uniform electrophysiological profiles responsive to cardioactive drugs. This efficient and cost-effective universal system for cardiac differentiation of hiPSC allows a potentially unlimited production of functional cardiomyocytes suitable for application to hPSC-based drug development, cardiac disease modeling, and the future generation of clinically-safe nonviral human cardiac cells for regenerative medicine.PLoS ONE 04/2011; 6(4):e18293. DOI:10.1371/journal.pone.0018293 · 3.23 Impact Factor
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- "The 1.75×10 5 cells/ml concentration was also used for the 200 and 300 µm Honeycomb Microwells. To achieve uniform EB size, 1 mL of the ESCs were then gently pipetted and dispensed drop-wise into each well of a 24-well plate (Chen et al., 2008; Nguyen et al., 2009). To prevent convective effects within each well of the 24-well plate, which may disrupt the uniform distribution, ESC were allowed to settle into the Honeycomb Microwells at room temperature for 15–30 m before being transferred into the incubator. "
ABSTRACT: The differentiation of embryonic stem cells (ESC) into tissue-specific cells utilizes either monolayer cultures or three-dimensional cell aggregates called embryoid bodies (EB). However, the generation of a large number of EB of controlled sizes can be challenging and labor intensive. Our laboratories have developed a simple, robust, ultra-rapid, and inexpensive design of Honeycomb Microwells for generation of EB. Here, we compare EB generated using (1) Honeycomb Microwells, (2) the commercially available AggreWell™400, and (3) the more traditional Hanging Drop method. We compared the efficiency, viability, quality, and control of EB sizes. Results indicate that the Honeycomb Microwell and AggreWell™400 efficiently generate small EB at approximately 500 cells per EB. However, the cone-bottomed AggreWell plate generates cone-shaped EB at 1000-2000 cells per EB. Moreover, the cone-shape correlates with a reduction in the formation of the primitive endoderm GATA-4+ cells (1% compared with 6-8% in spherical EB), but does not significantly affect mesoderm or ectoderm development. We conclude that the non-spherical EB shape correlates with a reduction in the development of primitive endoderm, and that use of these AggreWell plates should be avoided in deriving endoderm tissue products.