Stem Cell Differentiation and Cytogenetics

Group leader: Dr. Sylvia Ritter

Stem cells play a pivotal role in tissue development and maintenance by replenishing cells lost due to physiological tissue turnover or due to damaging agents such as ionizing radiation. To fully understand the effects of X-ray and particle exposure on stem cells and the underlying molecular mechanisms the group utilizes several cell models: embryonic stem cells, which can give rise to all tissues of an organism (left panel), their progeny (e.g. neural stem cells, middle panel) as well as bone marrow stem cells. Parameters such as cell survival, marker expression, differentiation capacity and genetic stability (left panel) are examined at various times after exposure. Currently, the group focuses on the effects of radon that is offered for the treatment of rheumatic diseases, carbon-ions that are increasingly used in cancer therapy and Fe-ions that are relevant for space Research


Main research topics

  • Radiation response of human embryonic stem cells and their progeny
    • Self-renewal
    • Differentiation/regeneration (neural cells, cardiomyocytes)
    • Functionality
    • Genetic stability
  • Cytogenetic damage in hematopoietic stem and somatic cells
    • Effects of radon spa therapy (in vivo studies)
    • RBE of HZE-particles heavy ions (in vitro studies)


  • Helmholtz Zentrum München, Germany ( Dr. O. Azimzadeh, Dr. S. Tapio)
  • University of Applied Sciences Aschaffenburg, Germany (Professor C. Thielemann)
  • Joint Institute for Nuclear Research, Dubna, Russia (Dr. E. Nasonova)
  • Technical University of Ilmenau, Germany (Prof. A. Schober)
  • Technical University of Darmstadt, Germany (Prof. B. Laube, Prof. M. Löbrich, Prof. G. Thiel)
  • Heidelberg University Hospital, Germany (Prof. J. Debus)


  • BMBF 02NUK049A (Verbundprojekt Brain Radiation Assay: Etablierung eines in vitro Systems zur Analyse und Prädiktion von Schäden im zentralen Nervensystem nach Exposition mit ionisierender Strahlung in Kombination mit anderen Neurotoxika)
  • BMBF 02NUK050A (Verbundprojekt GREWIS-alpha: Genetische Risiken und entzündungshemmende Wirkung von dicht-ionisierender alpha-Strahlung)
  • HGS-HIRE (Helmholtz Graduate School for Hadron and Ion Research)

Group members

  • Research scientists:
    Dr. Insa Schröder (Stem cells and Differentiation)
    Dr. Tamara Bender (Postdoc)
  • Technicians / Laboratory Engineers:
    Emilia Choman
    Kim Sara Jung
    Dr. Carola Hartel (L. E.)
    Dr. Yvonne Knies
  • PhD students:
    Kim Röder
    Celine Schielke
    Timo Smit
    Esther Schickel

Selected publications