Poster Presentation 6th Annual Meeting for Australasian Society for Stem Cell Research 2013

Novel monoclonal antibodies that identify human pluripotent stem cells. (#114)

Hun S Chy 1 , Carmel O'Brien 1 2 , Andrew L Laslett 1 2
  1. CSIRO, Future Manufacturing Flagship, Vic, Australia
  2. Monash University, Department of Anatomy & Developmental Biology, Clayton, Vic, Australia

The ability of human embryonic stem cells (hESC) and induced pluripotent stem cells (iPSC), collectively termed human pluripotent stem cells (hPSCs) to undergo indefinite self-renewal and differentiation into all cell types of the three embryonic germ layers makes them potentially useful for a wide range of therapeutic applications. However, these properties also confer a risk for tumorigenesis where residual hPSCs remain in differentiated cell populations destined for clinical applications.  There is a need to develop in vitro tools and rigorous assays that will enable both the enrichment of hPSCs for differentiation strategies and their stringent elimination from end point target cell populations.

We have previously identified genes associated with predicted cell surface expression that are upregulated in hPSCs, and downregulated in early stage differentiation1,2,3. We have generated a large number of novel monoclonal antibodies (MAbs) that detect live hPSCs by flow cytometry analysis and correlate with eighteen candidate cell surface antigens (unpublished). Extensive hPSC characterisation studies have been undertaken with these MAbs using multiparameter immunostaining and fluorescence activated cell sorting (FACS) analyses for two hESC lines and two hiPSC lines generated via different reprogramming strategies. Here we present data for a panel of novel MAbs, showing the detection and enrichment of hPSCs in comparison with cell surface markers SSEA-3, TRA-1-60, GCTM-2, CD9 and the transcription factor OCT3/4.  We also demonstrate the downregulation of MAb detection in embryoid body differentiation analyses over 28 days, and the correlation with OCT3/4 protein detection in these heterogeneous cultures.  We anticipate that these new MAb markers, when used in a combinatorial fashion, will greatly facilitate the enrichment of hPSCs as starting point populations for clinically relevant differentiation strategies, and will enable definitive detection of residual or reverting hPSCs4 to ensure the safe application of hPSC-derivatives.

  1. Laslett, A. L. et al. (2007). BMC Dev Biol 7: 12.
  2. Kolle, G. et al. (2009) STEM CELLS 27:2446–2456.
  3. Hough, S. et al. (2009) PLOS One Nov 5;4(11):e7708
  4. Polanco, J.C. et al. (2013) Stem Cells epub 3Jun 2013.