many subjects. Animal and cellular experiments finally validated that the new vaccine simultaneously improves the humoral and cellular immunity of BALB/c mice without side effects. All this results demonstrate that cordycepin could work as adjuvant to hepatitis b vaccine and systems-pharmacology analysis could be used as a new method to select adjuvants Introduction Adjuvants could elicit immune responses through different signaling pathways thus improve vaccine formulations for better protection, however, there are still very few adjuvants have been licensed for human because of the side effects or other problems. Even the widely used alum adjuvant could cause local reaction and IgE responses during vaccination. Therefore, there is a requirement to develop novel adjuvants for vaccines. Traditional Chinese Medicine (TCM) involves the use of natural products that have been utilized by humans for centuries for good health TCMs contain many bioactive ingredients with beneficial effects, and thus have attracted much attention in recent years. Although herbal medicines are comprised of several ingredients that target multiple organs, it is difficult to pin-point the bioactive compounds by traditional pharmacological methods. In addition, TCMs are not widely used outside of China and other Asian countries because of the lack of scientific data on their mechanisms of drug action. Thus, additional studies are needed to identify the underlying mechanisms Systems pharmacology, an emerging area of pharmacology, combines drug-like2 many subjects. Animal and cellular experiments finally validated that the new vaccine simultaneously improves the humoral and cellular immunity of BALB/c mice without side effects. All this results demonstrate that cordycepin could work as adjuvant to hepatitis b vaccine and systems-pharmacology analysis could be used as a new method to select adjuvants. Introduction Adjuvants could elicit immune responses through different signaling pathways thus improve vaccine formulations for better protection1 , however, there are still very few adjuvants have been licensed for human because of the side effects or other problems2-4. Even the widely used alum adjuvant could cause local reaction and IgE responses during vaccination. Therefore, there is a requirement to develop novel adjuvants for vaccines. Traditional Chinese Medicine (TCM) involves the use of natural products that have been utilized by humans for centuries for good health5 . TCMs contain many bioactive ingredients with beneficial effects, and thus have attracted much attention in recent years6 . Although herbal medicines are comprised of several ingredients that target multiple organs, it is difficult to pin-point the bioactive compounds by traditional pharmacological methods. In addition, TCMs are not widely used outside of China and other Asian countries because of the lack of scientific data on their mechanisms of drug action7 . Thus, additional studies are needed to identify the underlying mechanisms. Systems pharmacology, an emerging area of pharmacology, combines drug-like