1. Historical Microscopy Foundation, Visseringlaan 25, 2288 ER, Rijswijk, The Netherlands
2. Department of Dermatology, Leiden University Medical Centre, Albinusdreef 2, 2333 ZA,Leiden University, Leiden, The Netherlands
3. Department of Biotechnology and Delft Science Centre, Delft University of Technology, Mijnbouwstraat 120, 2628 RX Delft, The Netherlands