Human T- and B-cell epitopes of E1 glycoprotein of rubella virus

The identification of T- and B-cell sites recognized frequently by human populations could provide the basis for selecting the candidate T- and B-cell epitopes for the development of an effective synthetic vaccine against rubella. Rubella virus E1 glycoprotein has been shown to be the predominant antigen to which the majority of human populations develop lymphocyte proliferative and antibody responses. To define the T- and B-cell epitopes of E1 glycoprotein of rubella virus, 23 overlapping synthetic peptides corresponding to more than 90% of the amino acid sequence of E1 were synthesized and tested for their capacities to induce proliferative and antibody responses of 10 seropositive individuals. The most frequently recognized T-cell epitopes were EP19 (residues 324-343), with 7 of 10 responders, and both EP12 (residues 207-226) and EP17 (residues 289-308), with 6 of 10 responders, respectively. Two immunodominant linear B-cell epitopes were mapped to residues 157 to 176 (EP9, 8/10) and 374 to 390 (EP22, 6/10) by using peptide-specific enzyme linked immunosorbent assay.