JULY 10, 2009--New data presented during this week's International Society for Stem Cell Research (ISSCR) Annual Meeting (July 8-11; Barcelona, Spain) by BD Biosciences (San Diego, CA) highlights two novel flow cytometry-based sorting and analysis methods for neural and embryonic stem cell research. The presentations, says BD, further validate the viability of tools used for separating near-pure populations of stem cell-derived neurons from undifferentiated stem cells (Abstract ID 2276, Poster ID 1177) and show improved cell recovery and survival of human embryonic stem cells (hESCs) after cell sorting (Abstract 2268, Poster ID 1170).
In the first study, researchers used a novel flow cytometry-based screen assessing 192 antibodies to cell surface markers to identify a cell surface signature that effectively distinguished neurons from hESC-derived neural stem cells (NSCs) and hESCs. Researchers used this cell surface signature in combination with flow cytometry to separate the undifferentiated cells from the differentiated cell types. This method reduces the variability of cell preparations from experiment-to-experiment and may help facilitate the development of assays requiring pure or consistent cell populations, such as genomics, transplantation experiments, in vitro drug testing and other in vitro assays where results may be confounded by unwanted cell types.
"Our study results help address a key challenge in the development of assays that will benefit from consistent, defined neural cell types," said Christian Carson, Stem Cell Scientist, BD Biosciences (a segment of Becton, Dickinson and Company) and the study's senior author. "In addition, these findings have implications beyond neural stem cells. They provide a framework of how to use flow cytometry analysis screens and sorting methods to quickly identify and isolate a variety of stem cells and their derivatives."
The second study demonstrates the successful application of the p160-Rho-associated coiled kinase (ROCK) inhibitor after cell sorting to improve cell survival in both feeder-dependent and feeder-independent growth conditions. Flow cytometry is a powerful tool used to effectively isolate and sort subpopulations of hESCs based on multiple markers, but due to the inherent sensitivity of hESCs, the recovery and survival of these cells can be low. However, the study found that by utilizing the ROCK inhibitor upon completion of cell sorting, researchers were able to improve recovery, enabling higher yield in experiments. Importantly, sorting and application of the ROCK inhibitor did not appear to negatively affect the cells. The sorted cells retain normal morphology, maintain a stable karyotype after many cell passages, and maintain their ability to differentiate into all three germ layers.
"Stem cell research is an increasingly complex and exhilarating area of science where researchers are looking to find answers to some of the most difficult to treat medical conditions," says Jay Glasscock, President, Cell Analysis, BD Biosciences. "BD Biosciences is committed to working with the stem cell research community to help develop state-of-the-art tools that support and further enhance experiment capabilities."
The study titled "Isolation of a near-pure population of hESC-derived neurons using CD markers and fluorescence activated cell sorting (Abstract 2276)" was funded in collaboration with Lawrence S. Goldstein, Ph.D. and his laboratory at the University of California, San Diego.1 Its lead author was Shauna Yuan, M.D., a post-doctoral fellow.
1 Yuan S, Paramban R, Martin J, Vidal JG, Goldstein LS, Carson CT. Isolation of a near-pure population of hESC-derived neurons using CD markers and fluorescence activated cell sorting. Poster presented at: ISSCR 7th Annual Meeting.