Team IMT: Immunosuppressive Microenvironment of Tumors

Solid tumors are complex microenvironments composed of cancer and immune cells that interact through various regulatory networks. Although CD8 T-cells may recognize and kill tumor cells, their function is impaired by cells such as regulatory T-cells, tumor-associated macrophages (TAM), and myeloid-derived suppressor cells (MDSC). The success of the so-called checkpoint blockade strategy and numerous clinical and preclinical studies have demonstrated that alleviating immunosuppression translates into a therapeutic benefit.

Our team is exploring new strategies to relieve immunosuppression and improve anti-tumor response. Current projects focus on the establishment of antibody-discovery platforms, the isolation of specific antibodies, and their functionalization. Furthermore, our group develops platforms that allow investigation into the development and suppressive activity of myeloid cells in both human beings and mice.


  • Dr. Laura Helming
    Associate Director, Group Leader Cancer & Inflammation – ImmunoOncology, Merck, Darmstadt (Industry mentor)
  • Prof. Dr. Viktor Umansky
    Group Leader, Dermato-Oncology Unit, German Cancer Research Center (DKFZ), Heidelberg (Academic mentor)


    1. Schröder M, Loos S, Naumann SK, Bachran C, Krötschel M, Umansky V, Helming L, Swee LK.
      Identification of inhibitors of myeloid-derived suppressor cells activity through phenotypic chemical screening. Oncoimmunology. 2016
    2. Bachran C, Schröder M, Conrad L, Cragnolini JJ, Tafesse FG, Helming L, Ploegh HL, Swee LK.
      The activity of myeloid cell-specific VHH immunotoxins is target-, epitope-, subset- and organ dependent. Scientific Reports. 2017
The research of this team is kindly sponsored by Merck.
The research of this team is kindly sponsored by Merck.

Our Team Members

Dr. Lee Kim Swee

Group Leader

Previous work
  • 2010–2014: Postdoc with Prof. Hidde Ploegh, Whitehead Institute/MIT, USA
  • 2010: Scientist at Scil Technology, Munich, Germany
  • 2004–2008: PhD with Prof. Antonius Rolink, University of Basel, Switzerland
  • 2004: Master of Science, University of Lausanne, Switzerland

Dr. Stefanie Dannenmann

Postdoctoral Researcher

Previous work
  • 2012–2014: Head of the flow cytometry facility, Medical Faculty Ulm, Germany
  • 2012: PhD in Oncoimmunology, ETH/University of Zurich, Switzerland
  • 2005: Master of Science, Jacob University Bremen, Germany

Marit Krötschel

Research Associate

Previous work
  • 2005–2015: Research Assistant, Max Planck Institute of Immunology and Epigenetics, Freiburg, Germany
  • 2011–2013: Master in Health Sciences, University of Education, Freiburg, Germany
  • 2008–2011: Bachelor in Health Sciences, University of Education, Freiburg, Germany

Simone Loos

Research Associate

Previous work
  • 2013–2015: Master of Science in Biomedical Science and Technology, University of Applied Sciences, Mannheim, Germany
  • 2009–2013: Bachelor of Science in Biotechnology, University of Applied Sciences, Ansbach, Germany