UNIT 7.33 SYTO Probes: Markers of Apoptotic Cell Demise

  1. Donald Wlodkowic1,
  2. Joanna Skommer2

Published Online: 1 OCT 2007

DOI: 10.1002/0471142956.cy0733s42

Current Protocols in Cytometry

Current Protocols in Cytometry

How to Cite

Wlodkowic, D. and Skommer, J. 2007. SYTO Probes: Markers of Apoptotic Cell Demise. Current Protocols in Cytometry. 42:7.33:7.33.1–7.33.12.

Author Information

  1. 1

    University of Glasgow, UK

  2. 2

    University of Kuopio, Finland

Publication History

  1. Published Online: 1 OCT 2007
  2. Published Print: OCT 2007


As mechanistic studies on tumor cell death advance towards their ultimate translational goal, there is a need for specific, rapid, and high-throughput analytical tools to detect diverse cell demise modes. Patented DNA-binding SYTO probes, for example, are gaining increasing interest as easy-to-use markers of caspase-dependent apoptotic cell death. They are proving convenient for tracking apoptosis in diverse hematopoietic cell lines and primary tumor samples, and, due to their spectral characteristics, appear to be useful for the development of multiparameter flow cytometry assays. Herein, several protocols for multiparametric assessment of apoptotic events using SYTO probes are provided. There are protocols describing the use of green fluorescent SYTO 16 and red fluorescent SYTO 17 dyes in combination with plasma membrane permeability markers. Another protocol highlights the multiparametric use of SYTO 16 dye in conjunction with the mitochondrial membrane potential sensitive probe, tetramethylrhodamine methyl ester (TMRM), and the plasma membrane permeability marker, 7-aminoactinomycin D (7-AAD). Curr. Protocol. Cytom. 42:7.33.1-7.33.12. © 2007 by John Wiley & Sons, Inc.


  • SYTO;
  • apoptosis;
  • flow cytometry;
  • multi-parameter assay