Studies on the role of linear epitopes in neutralization of alphaviruses.

By using three synthetic peptides (16-19 amino acids in length) representing different regions of glycoproteins E1 (peptide 3) and E2 (peptides 1 and 2) of Sindbis and Semliki Forest virus and isolated glycoprotein fractions of both viruses in reduced and non-reduced form, the role of linear epitopes for the neutralization was investigated. The reaction patterns of sera induced by immunization with these antigens indicate that conformational epitopes do play the major role in neutralization of alphaviruses. Furthermore, no cross-neutralization of these alphaviruses classified in different antigenic complexes within this genus was found.