Generation of a complete genomic copy of hepatitis A virus adapted to replicate in Vero cells

AGUIRRE, SEBASTIAN; MARENGO, JUAN; SCODELLER, EDUARDO; MATTION, NORA

Punta del Este, Uruguay

Workshop; Molecular Biology of Viral Diseases; 2009

ICGEB/PAHO/RELAB

Hepatitis A virus (HAV), has been adapted to grow in a variety of primate cell lines. In contrast to other picornavirus, HAV presents a slow replication phenotype, with no cytopathic effect (cpe) in most cases. These characteristics are given by genetic determinants involved in replication, a high rate of rare codon usage which delays the viral polyprotein expression, and also by the host cell environment. Vaccination against HAV has been incorporated in the Argentine Immunization Program since 2005, being the vaccine provision exclusively from foreign manufacturing  companies. The existing vaccines are formulated with inactivated, purified virus particles, and are highly immunogenic. In order to generate a cultivatable vaccine strain to be manufactured in Argentina, a HAV strain (HM-175-43c) which shows a rr+/cpe+ phenotype in FRhK-4 cells, was adapted to grow at high replication rate in a cell substrate (Vero) approved for human vaccine production .The recovered virus would be used for the generation of a vaccine seed strain free of adventitious agents.