Detection of conserved and nonconserved epitopes on Coxsackievirus B4: frequency of antigenic change.

A sensitive microneutralization assay was used to detect antigenic variants of Coxsackievirus B4. Analysis of 47 clinical isolates with 16 monoclonal neutralizing antibodies revealed highly conserved, moderately conserved, and poorly conserved epitopes. Upon passage of Coxsackievirus B4 in tissue culture, certain epitopes disappeared and others appeared in the apparent absence of selective pressure. Changes in epitopes often exceeded a frequency of 10(-2). Despite considerable variation in individual epitopes, the overall antigenic composition of Coxsackievirus B4, as measured by the capacity of hyperimmune serum to neutralize clinical isolates, remains fairly constant.