Common antigen between coxsackievirus A 16 and enterovirus 71

Area of Science:

• Virology
• Immunology
• Public Health

Background:

• Enterovirus 71 (E 71) and Coxsackievirus A 16 (CA 16) are significant enterovirus serotypes causing hand, foot, and mouth disease (HFMD).
• Understanding cross-reactivity between enterovirus serotypes is crucial for vaccine development and disease control strategies.

Purpose of the Study:

• To investigate the antigenic relationship between Coxsackievirus A 16 and Enterovirus 71.
• To characterize the nature and origin of any shared antigens.

Main Methods:

• Cross immunofluorescence assays were performed to detect shared antigens.
• Complement fixation tests utilized purified virus preparations fractionated by sucrose density gradient centrifugation.
• Immuno-diffusion techniques were employed to further confirm antigen presence.

Main Results:

• Cross immunofluorescence confirmed a shared antigen between CA 16 and E 71.
• Complement fixation tests identified two peaks of antigenicity: one type-specific and one cross-reactive.
• The common antigen was found to be heat-stable and associated with empty viral capsids.
• Infants recovering from CA 16-induced HFMD developed antibodies against E 71.

Conclusions:

• A common, heat-stable antigen exists between CA 16 and E 71, likely located on empty capsids.
• This antigenic cross-reactivity may induce protective immunity against E 71 following CA 16 infection.