1. Division of Mucosal Immunology and Diagnostics, Research Center Borstel, Parkallee 22, 23845 Borstel, Germany
2. Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93040 Regensburg, Germany
3. Department of Analytical Biotechnology, Veterinary Research Institute, Hudcova 70, 621 32 Brno, Czech Republic