Place: Kleiner Physik-Hörsaal, Geschwister-Scholl-Platz
Date: 19.10.2012, Time: 16:30 h
Investigating target-cell killing in amoebae
Prof. Dr. Christine Selhuber-Unkel
Institute for Materials Science, Christian-Albrechts-Universität Kiel
The pathogenic amoeba Acanthamoeba castellanii can cause severe diseases such as Acanthamoeba keratitis. 90% of the patients with this painful disease are contact lens users, who are infected with Acanthamoeba due to wrong contact lens care. Through small lesions of the epithelial cells the amoebae get into the eye and start to destroy target cells by an extracellular killing mechanism. A crucial first step during this killing process is the formation of a close contact between an Acanthamoeba and a target cell. This initial contact is supposed to be mediated by carbohydrates. Subsequently, intracellular granules move towards the contact site and release pore-forming molecules into the extracellular space. These pore-forming molecules presumably perforate the membrane of the target cell and induce target-cell apoptosis.
In our work, we aim at understanding the adhesion behavior of amoebae to target cells and the subsequent intracellular processes. We use live-cell imaging and force microscopy to investigate both the adhesion of amoebae to target cells as well as the intra-amoebic dynamics of granule transport. Furthermore, we develop carbohydrate-functionalized materials to elucidate the initial contact between amoebae and target-cells. Combining these different aspects should finally give us a comprehensive picture of Acanthamoeba pathogenicity.