Der Browser den Sie verwenden ist sehr alt.

Wir können daher nicht sicherstellen, dass jede Funktion (Gestaltung, Bilder und zusätzliche Funktionen) dieser Internetseite im vollen Umfang zur Verfügung steht. Bitte nutzen Sie eine aktuellere Browserversion.
Wir bitten um Ihr Verständnis.
Startseite > Forschung > Arbeitsgruppen > Arbeitsgruppe Prof. Dr. rer. biol. hum. Ottmar Janßen > english version Janßen

Research Group Prof. Dr. rer. biol. hum. Ottmar Janßen


1. Name of Group

Molecular Immunology


2. Key sentence

Cytotoxic T and NK cells eliminate infected or transformed cells by the targeted release of effector molecules. Decyphering the molecular regulation of underlying processes is a prerequisite to modulate in order to optimize therapeutical approaches to fight cancer, infections and other immunopathologies.


3. Keywords

cytotoxic T cells, NK cells, effector proteins, signal transduction, lysosome-related effector vesicles, exosomes


4. Group members

  • Group Leader: Universityprofessor Dr. rer. biol. hum. Ottmar Janßen
  • Scientists: PD Dr. rer. nat. Marcus Lettau
  • Technician: Ina Martens (until 07/2018)
  • Students: Mai Dang Thi (cand. med.), Katharina Dohmen (cand. med.), Michelle Dietz (cand. med.), Gerrit Hugendieck (cand. med.) Lisann Drews (until 11/2018) Sarah Vollmers (MSc BCM, until 12/20) Luis Fonseca Brito (MSc MLS, until 09/18) Sheng-Hsiang Shen (MSc MLS, until 09/18)


5. Scientific Profile

We are interested in signaling pathways that regulate the activation, effector function and death of NK cells and T lymphocytes. As effector cells of the innate and adaptive immune system, these cell types are in charge of eliminating infected or malignant cells in an immunologically silent fashion. Activation of individual effector cells requires cell-type-specific signals whereas the arsenal of effector proteins widely overlaps. We could recently show that T and NK cells store their live ammunition in distinct storage organelles to mobilize them individually on demand. Presently, we investigate how the targeted release of individual effector proteins might be modulated by differential activation regimen. T and NK cells (as most other cells of the body) also release extracellular vesicles, which may be regarded as a fingerprint of the original cell. We believe that such extracellular vesicles are at least in part derived from the pool of intracellular effector vesicles and are released into the local micromilieu to amplify the immune response by enabling an intracellular communication also at longer distances. To investigate the different phenomena, we employ cell biological, molecular biological and biochemical approaches and methods including cell culture, flow cytometry, imaging flow cytometry, ELISA, Western blotting and proteomics.


6.   List of scientific projects

  • Maturation and subpopulation-specific distribution of cytotoxic effector vesicles in human T and NK cells
  • Comparative characterization of intra- and extracellular effector vesicles from T and NK cells


7.   Selected publications

  • Ebsen H, Schröder A, Kabelitz D, Janssen O. Differential surface appearance of ADAM10 and ADAM17 on human T lymphocytes and tumor cells. Plos One. 2013, 8(10): e76853
  • Lettau M, Kabelitz D, Janssen O. SDF1α-induced interaction of the adapter proteins Nck and HS1 facilitates actin polymerization and migration in T cells. Eur J Immunol. 2014, 45: 551-561
  • Ebsen H, Lettau M, Kabelitz D, Janssen O. Subcellular localization and activation of ADAM proteases in the context of FasL shedding in T lymphocytes. Mol Immunol, 2015, 65: 416-428
  • Lettau M, Kabelitz D, Janssen O. Lysosome-related effector vesicles in T lymphocytes and NK cells. Scand J Immunol, 2015, 82: 235-243
  • Lettau M,  Armbrust  F, Dohmen K, Drews L, Dietz M, Poch T, Kabelitz D, Janssen O. Mechanistic peculiarities of activation-induced mobilization of cytotoxic effector proteins in human T cells. Int Immunol, 2018, 30: 215-228


Complete Publication list



8.   Third party funding projects

  • Medical Faculty, CAU Kiel (2018)
  • Deutsche Forschungsgemeinschaft (DFG), JA 610/7-1 (6/2015-6/2018)  


9. List of cooperation partners

  • Prof. Dr. Dirk Bauerschlag, Department of Gynecology, UKSH Kiel
  • Prof. Dr. Dieter Kabelitz, Institute for Immunology, Kiel
  • Prof. Dr. Matthias Leippe, Zoological Institute, CAU, Kiel
  • Prof. Dr. Susanne Sebens, Institute for Experimental Tumor Research
  • Prof. Dr. Andreas Tholey, IKMB, Kiel
  • PD Dr. Guido Wabnitz, Institute for Immunology, University of Heidelberg
  • Prof. Dr. Carsten Watzl, IFADO, Dortmund