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Using microRNAs to enhance the generation of induced pluripotent stem cells.

Program for RNA Biology, Sanford-Burnham Medical Research Institute, La Jolla, California, USA.
Current protocols in stem cell biology 03/2012; Chapter 4:Unit 4A.4. DOI: 10.1002/9780470151808.sc04a04s20
Source: PubMed

ABSTRACT Somatic cells reprogrammed to acquire an ES-like state are termed iPS cells. In this unit, a protocol to use microRNAs as enhancers to increase the reprogramming efficiency is described. Mouse embryonic fibroblasts (MEFs) are isolated from E13.5 mouse embryos and seeded for reprogramming by defined factors. microRNA mimics are transfected into MEFs at two time points during this process to enhance the overall reprogramming efficiency. Two standard protocols for characterization of these miR-iPSCs, embryoid body formation and teratoma formation, are also provided. By using this method, the investigators can obtain a significantly higher number of bona-fide iPSC colonies and miR-iPSCs can be derived at a faster rate than with non-treated cells.

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    • "Work from Ali et al. clearly demonstrates that the post-mitotic photoreceptor precursor cell is the optimal cell type for efficient rod photoreceptor cell replacement (Lakowski et al., 2011; Pearson et al., 2012). A variety of different protocols, utilizing both two-and three-dimensional culture systems, have succeeded in deriving photoreceptor precursor cells from less differentiated precursors (Osakada et al., 2008; Hirami et al., 2009; Meyer et al., 2009; Osakada et al., 2009; Lamba et al., 2010; Meyer et al., 2011; Tucker et al., 2011; Nakano et al., 2012; Phillips et al., 2012; Sasai et al., 2012; Homma et al., 2013; Mekala et al., 2013; Tucker et al., 2013). Although cultured three-dimensional eyecups will undoubtedly have many applications in developmental biology (Nakano et al., 2012; Sasai et al., 2012), two-dimensional systems have the advantage of easier identification and isolation of specific cell types for post-differentiation subculture. "
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