Keratins provide virus-dependent protection or predisposition to injury in coxsackievirus-induced pancreatitis
DM Toivola1, SE Ostrowski2, H Baribault3, TM Magin4, AI Ramsingh2, MB Omary5
1Åbo Akademi University, Dept. Biology, BioCity, Turku, Finland and Stanford University School of Medicine and Digestive Disease Center; 2New York State Department of Health, Albany, NY, USA; 3Amgen, South San Francisco, CA, USA; 4University of Bonn, Bonn, Germany; 5Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Mi, USA
Abstract: Keratins 8 and 18 (K8/K18) are the two major intermediate filament proteins in hepatocytes and pancreatic acinar cells. Acinar cell keratins are organized as cytoplasmic and apicolateral filaments. An important role of hepatocyte K8/K18 is to maintain cellular integrity, while this cytoprotective function of K8/K18 is not evident in the pancreas since keratin-deficient mice cope well with pancreatitis models. To further study the roles of keratins in the exocrine pancreas, we used coxsackievirus B4-models, CVB4-V and CVB4-P, to induce severe acute/chronic pancreatitis and acute pancreatitis, respectively, in K8-null (which lack acinar keratins) and K18-null (which lack cytoplasmic keratins) mice. Despite similar virus titers in all mice, CVB4-V resulted in 40% mortality of the K8-null mice 14 days post-infection compared to no lethality of WT and K18-null mice. In contrast, K8-null mice were far less susceptible to CVB4-P-induced damage as determined by histology and serology analysis, and they recover faster than WT and K18-null mice. After CVB4 virus infection, keratins aggregated during acinar degranulation, and K8/K18 site-specific phosphorylation was observed during degranulation and recovery. Hence, keratins significantly affect CVB4 virulence, positively or negatively, depending on the virus subtype and keratin makeup, in a virus replication-independent manner.
Keywords: keratin, pancreatitis, coxsackievirus
© 2009 The Author(s). This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.