[1][2] In the early 1980s in the laboratory of later Nobel Prize laureate Harald zur Hausen he was the first (together with the postgraduates Matthias Dürst and Michael Boshart supervised by him) to isolate and characterize HPV16 and HPV18, the two most oncogenic HPV types causing the vast majority of HPV-induced anogenital and head-and-neck cancers.
Together with Harald zur Hausen he moved to the University of Freiburg as a post doc and later became assistant professor in virology.
He was on leave of absence from 1993 to 1997 as director of research in the department of Obstetrics and Gynecology and chairman of the program Viral Oncology at the Loyola University Medical Center, Chicago, USA, and from 1998 to 1999 as vice president of research and development, MediGene AG, Martinsried, Germany.
Under his guidance numerous diploma and Ph.D. students were introduced to the fascination of science and the fun side of life in a research laboratory.
He received several honorary memberships and awards (including the Warren Alpert Foundation Prize in 2007 together with Harald zur Hausen "for work leading to the development of a vaccine against human papillomavirus").