Stan Lemon investigates mechanisms by which hepatotropic positive-strand RNA viruses replicate in the liver and cause diseases ranging from acute inflammatory hepatitis to cancer. His laboratory focuses on hepatitis A virus (HAV, a picornavirus) and hepatitis C virus (HCV, a flavivirus). His past research has elucidated the structure and function of the 5’ and 3’ untranslated RNAs of these viruses, and among other accomplishments discovered the existence of the internal cre, a cis-acting RNA replication element, in picornaviruses, mapped the secondary structure and function of the internal ribosome entry sites (IRESs) of both HAV and HCV, and identified and characterized the unique host function of the microRNA, miR-122, in replication of HCV. Over the past decade, his interests have evolved to include how these viral RNAs are recognized by host innate immune sensors, how HAV and HCV have evolved similar but also distinct mechanisms to evade antiviral defenses in the liver, and how these events influence inflammation and the development of immunity. His group discovered that HAV is released non-lytically from cells cloaked in host cell membranes, and circulates in the blood of infected humans in a quasi-enveloped form resistant to neutralizing anti-HAV antibodies. These seminal observations have blurred the classic distinction between enveloped and non-enveloped viruses, and thus challenged a basic, long held tenet of virology.
Relevance of Research to CGIBD Mission: Dr. Lemon studies hepatitis A and hepatitis C. Although liver research is a minor part of the CGIBD portfolio (we are not one of the designated liver centers), reducing the burden of liver disease is important to our mission. After returning to Chapel Hill from Galveston, where he served as Dean of the School of Medicine, he served on the CGIBD Executive Committee. He currently serves the CGIBD as a senior advisor to CGIBD members who study liver disease.
CGIBD Focus Area(s): Microbiome
Pilot and Feasibility Award 1996
Collaborators: Fried, Ting