HHEX and infection: By infecting human hepatic cells lines or rhesus macaques with the highly virulent strain LCMV-WE or the related avirulent strain LCMV-ARM, it was found that LCMV-WE infection of liver cells leads to drastic reduction of PRH expression, while the level of expression remains unaltered during infection with the avirulent LCMV-ARM [170].