Nowadays, many eukaryotic expression systems have been commercialized [37], which including monoclonal antibodies production in mammalian cells [38], some viral vaccines production in baculovirus expression vector system [39], hepatitis B vaccine production in Saccharomyces cerevisiae [40] and insulin glargine production in P. pastoris [37], all these expression systems have the ability of N-glycosylation modification. Here, INS is linked to hepatitis B virus infection.