Prof. Dr. rer. nat. Martin Schwemmle
University of Freiburg
Phone: +49 (0)761 203 6526, Fax:+49 (0) 761 203 6639
Avian influenza viruses sporadically infect humans but usually do not transmit between individuals due to innate immune responses that efficiently protect from zoonotic infections. In rare cases, however, these viruses establish a new virus lineage in the human population, resulting in devastating morbidity and mortality. We areinterested in the adaptation processes of avian influenza viruses, including highly pathogenic H5N1 and H7N9 to humans. This includes the identification of virus-specific changes that allow efficient replication in human cells as well as changes required to overcome innate immune responses. We could recently show that impaired synthesis of the viral genome represents one major defect of avian polymerases in human cells. While the precise mechanisms remain to be unveiled, it appears that a broad spectrum of adaptive mutations in the polymerase and the viral nuclear export protein NEP can act collectively to overcome this defect. We also identified a discrete set of adaptive mutations in the viral nucleoprotein of human influenza A virus strains that are essential to escape from the antivirally active host restriction factor MxA. We hope with these studies to gain both deep insights into the mechanisms of avian influenza viruses to successfully adapt to humans and the development of new antiviral approaches that protect from such species transmissions.