Expression and immunogenicity of V sub(3) loop epitopes of HIV-1, isolates SC and WMJ2, inserted in Salmonella flagellin

• Published in: Journal of biotechnology Vol. 56; no. 3; pp. 191 - 203
• Main Authors: Cattozzo, E M, Stocker, BAD, Radaelli, A, De Giuli Morghen, C, Tognon, M
• Format: Journal Article
• Language: English
• Published: 01.08.1997
• ISSN: 0168-1656

Synthetic oligonucleotides corresponding to specific V sub(3) loop portions of two HIV-1 isolates, SC and WMJ2, were expressed in the flagella of a Salmonella live-vaccine strain. Expression of the inserted epitopes in flagellin and their exposure at the surface of flagellar filaments were shown by immunoblotting and immunogold labeling with anti-flagellin (Salmonella d) and anti-HIV-1(IIIB) V sub(3) loop peptide sera. Live recombinant Salmonella strains expressing either one of the two V sub(3) loop inserts were administered intraperitoneally to BALB/c mice. All these animals developed antibodies specific for the heterologous glycoprotein 120 (gp120) of HIV-1 MN strain, as detected by enzyme-linked immunosorbent assays (ELISA); two of the sera had neutralizing activity against the heterologous HIV-1 MN strain. Moreover, oral administration of the live Salmonella recombinant strains to mice evoked specific IgA directed against gp120.