Anice C. Lowen, PhD

ARTDTP Research Discipline:

The Lowen lab focuses on two aspects of influenza virus biology: transmission of the virus from host-to-host and reassortment of the viral gene segments. Transmission studies: Despite its clear importance to the epidemiology of influenza, the process by which human influenza viruses travel from one individual to another is not well understood. The lack of transmission of H5N1 influenza viruses among humans and other mammals has shown that, contrary to expectation, viral growth is not the only prerequisite for transmission. Research over the past six years has revealed that viral, host and environmental factors each play a role in determining the efficiency with which an influenza virus transmits. They previously showed, for example, that humidity and temperature have a strong impact on the efficiency of transmission, that host-specific adaptive changes in the viral polymerase can alter transmission efficiency, and that host immunity resulting from vaccination or natural infection limits transmission to varying degrees. Despite such progress, an in-depth understanding of transmission remains a high priority in the influenza field. The group previously demonstrated that guinea pigs reflect humans well in terms of influenza virus transmissibility and therefore use this animal model system for our studies. One highly important question that we are able to address in this model is the potential for certain antiviral drugs and vaccination approaches to limit the transmission of influenza viruses. Reassortment studies: Reassortment is the process by which influenza viruses, which carry RNA genomes comprising eight segments, exchange genetic material. Reassortment of the genome segments of two differing influenza strains has the potential to vastly increase the diversity of circulating influenza viruses. Despite its importance to influenza virus evolution, the frequency with which reassortment occurs in an animal infected with two or more variant viruses is unclear. The group is working to assess the incidence of reassortment in experimentally infected guinea pigs. By studying the process under well-controlled conditions, they aim to identify factors that dictate how readily reassortment can occur. For example, the roles of pre-existing immunity to one subtype, sequential rather than coincident infection, genetic compatibility between differing viruses, and the likelihood of two distinct strains to infect the same cell type will be studied. Importantly, the impact of antiviral treatment and vaccination on reassortment potential will also be evaluated. One important question is whether reassortment between wild-type and antiviral resistant influenza viruses allows for rapid escape from antiviral drugs.

ARTDTP Faculty Collaborators:

Richard W. Compans, PhD
David A. Steinhauer, PhD