Activity of a synthetic microbicidal peptide against Influenza A virus multiplication

10 Activity of a synthetic microbicidal peptide against Influenza A virus multiplication Conti G., Magliani V., Portincasa P., Conti S., Polonelli L. Department of Pathology and Laboratory Medicine- Microbiology Section - University of Parma A killer peptide (KP) engineered from the sequence of the variable region of a recombinant antiidiotypic antibody representing the internal image of a killer toxin, is characterized by the wide spectrum of microbicidal activity against pathogenic eukaryotic and prokaryotic microrganisms. Based on the surprising sequence homology of KP with the light chain variable region of an antibody (HC63) that prevents the haemagglutinin, HA, low pH fusogenic transition of Influenza A virus, we report the “in vitro” inhibition of Influenza A virus multiplication in LLC-MK2 cells which is mediated by a marked reduction of glycosylation of HA, as well as its synthesis. The restriction of the production of mature virion particles could be the result of a defect involving the migration and / or the association - insertion of virus haemagglutinin HA into the plasma membrane of infected LLC-MK2 cells treated with KP. Moreover, this hypothesis is also in good agreement with the haemadsorption as well as immunoprecipitation experiment results.