• Research interests

    Human spermatogonial stem cells (SSCs) form the foundation of spermatogenesis as they can self-renew or differentiate into sperm and are therefore highly interesting. A better understanding of the properties of SSCs is crucial as these cells have the potential to be used for fertility preservation approaches, for instance in pre-pubertal cancer survivors who often become infertile following cancer treatment.


    My research goal is to unravel the epigenetic and transcriptional properties of the general population of spermatogonia during development. Understanding of the normal situation will be crucial to assess abnormal patterns in infertility patients. Moreover, molecular properties of spermatogonia may provide information regarding the conditions that will support the in vitro propagation of these cells.


    In recent years, we have successfully set up approaches for the isolation and characterization of human spermatogonia focusing on epigenetic dynamics during development and in vitro. Moreover, comparative transcriptional analysis of spermatogonial populations and single cells has revealed that the single cell approach can unravel hitherto unknown properties of these cells.

    Characterization of spermatogonia in vitro and selection of spermatogonial clones.
    A. Immunofluorescence stainings of human germ cells stained for MAGE A4 (green)
    and DDX4 (red) (modified from Kossack et al. 2013).
    B. Micromanipulation of spermatogonial clusters.