Enteroviruses are nonenveloped, positive-sense single-stranded RNA viru
ses that belong to the family Picornaviridae and genus Enterovirus. More t
han 100 human enteroviruses have been identified, including polioviruse
s, coxsackieviruses group A (CVA), coxsackieviruses group B (CVB), entero
viruses (EV, 68 to 71) and echoviruses. Hand, foot, and mouth disease (HF
MD) is primarily a childhood disease that has garnered attention worldwid
e in the last 20 years. HFMD is caused by infection with human enterovirus
es, particularly the EV-A71 and CVA. Several HFMD pathogens are associat
ed with severe clinical complications especially in the Asia-Pacific countrie
s. However, the monovalent EV-A71 vaccines showed poor cross-neutraliz
ation against CVAs in preclinical studies. Formalin-inactivated EV-A71 vac
cines are developed from virions produced by Vero cells. However, most c
oxsackievirus clinical isolates are reported to have low culture efficiency in
Vero cells, and lead to difficulty in producing whole viral particles for the d
evelopment of inactivated vaccines. Cell lines, culture media and manufact
uring processes are important elements for cell-based viral vaccine produ
ction. We have tested several cell lines for enterovirus production and fou
nd that HEK293 is a potent cell for coxsackievirus propagation. We also es
tablish serum-free culture system for cell-based inactivated vaccine produ
ction. This technique is a novel method for preparing enterovirus vaccines
using HEK293 cells. Serum-free HEK293 cells can be scaled up in attached
or suspension culture system, and it can also be used to culture various ty
pes of enteroviruses. The production of different enterovirus antigens can
be included in a multivalent HFMD virus vaccine, which can be use to cont
rol the epidemic of multiple HFMD diseases.