Hepatitis E virus of different genotypes contains multiple-type antigenic epitopes
不同基因型戊型肝炎病毒存在多种类型抗原表位

Monoclonal antibodies (McAbs) were prepared against a recombinant protein p166Us derived from US-1 strain of hepatitis E virus (HEV). The immune reactivity of the McAbs to seven p166s derived from different genotypes and subtypes of HEV, which included p166Bur (genotype I a), p166Pak (genotype I b), p166Mor (genotype I c), p166Mex (genotype II), p166Us (genotype III), p166Nz (swine HEV, genotype III) and p166Chn (genotype IV), was tested by an indirect enzyme-linked immunosorbent assay (ELISA) and a Western blotting assay. The immunological relationship between the McAbs and native HEV particles or anti-HEV positive serum samples was analyzed by an antigen-competitive or antibody-competitive ELISA. Totally, six McAb-producible hybridoma cell lines, designated by the name of 4D3, 2E3, 11E11, 12H5, 3A3 and 1F1 respectively, were cloned and obtained in this study. The McAb of 4D3 could react to all of the seven p166 recombinant proteins. This kind of reaction could be inhibited by each of 4 genotypes of native HEV particles or anti-HEV positive serum samples. The McAbs produced by 2E3, 11E11 and 12H5 reacted to p166Us, p166Nz and p166Chn, but did not react to p166Bur, p166Pak, p166Mor and p166Mex. The reaction of McAb of 2E3, as an example of the McAbs of 2E3, 11E11 and 12H5, could be only inhibited by genotype III and IV HEV or anti-HEV positive serum. The McAb of 3A3 could bind to p166Us as well as p166Nz. The McAb produced by 1F1 was reactive to the p166Us only. However, neither of I , II , IV genotype HEV particles or antisera could inhibit both of their reactions to p166Us. The data as mentioned above suggested that there are multiple-type antigenic epitopes such as genotype I, II, III and IV common, III and IV common, and III specific epitopes within HEV ORF2 encoded p166 proteins of different genotypes and subtypes of HEV. Moreover, the antigenic epitopes on recombinant protein p166s and these on native HEV particles possess identical immunological characteristics.