Four antigenic domains, A to D, have been identified on E2. On the basis of neutralization and conservation, domain A is divided into subdomains A1, A2, and A3. Subdomain A1 is conserved in different CSFV strains and the MAbs of the A1 are neutralizing.

• E2存在4个不同抗原区(A-D),根据中和特性和保守性差异,将A抗原区进一步划分为A1、A2、A3抗原亚区,A1抗原亚区在不同猪瘟病毒分离毒株中高度保守且诱导的单克隆抗体具有中和特性。