Peptide immunogen

Several plant vims coat proteins, including those of TMV, CPMV, AlMV and Tomato bushy stunt vims (TBSV), have been used to produce and deliver antigenic determinants from a variety of viral and bacterial pathogens. These data have been summarized in numerous publications and several reviews [12,13]. The ease of virus purification coupled with enhanced peptide immunogenicity when fused to carrier molecules makes this approach very attractive for vaccine development. 

The methods described are suitable for use with immunogens derived from a variety of sources, for example, bacterially expressed fusion proteins, baculovirus-expressed proteins or synthetic peptides conjugated to suitable carrier proteins (see Chapter 2). Antibody responses to peptide immunogens often differ from those where the immunogen is a larger macromolecule in that maximal antipeptide titres (which arise rapidly after two to three immunizations) do not always coincide with maximal titres against the intact... 

Because synthetic peptide immunogens used to generate antipeptide antibodies often are available in comparatively large... 

Fig. 2. Immunogenicity of synthesized lipopeptide and nonlipidated peptide. Groups of BALB/c mice (6-8 wk old) were inoculated subcutaneously with 20 nmol of peptide immunogens in both primary and secondary inoculations. All lipopeptides were administered in saline, and the nonlipidated peptide was administered in either CFA or saline. Sera were obtained from blood taken 4 wk following the primary (open circles) inoculation and 2 wk following the secondary (closed circles) inoculation. Antibody levels were determined by ELISA. Individual antibody titers are presented with the mean value represented by the horizontal bar.

Incidence of Pregnancy Following Inoculation with Peptide Immunogens... 

Toth I, Danton M, Flinn N, Gibbons WA (1993) A combined adjuvant and carrier system for enhancing synthetic peptides immunogenicity utilizing lipidic amino acids. Tetrahedron Lett 34(24) 3925-3928... 

Olive, C., Batzloff, M., Horvath, A., et al. (2003) Potential of lipid core peptide technology as a novel self-adjuvanting vaccine delivery system for multiple different synthetic peptide immunogens. Infection and Immunity 71, 2373-2383. 

Sundaram R, Lynch MP, Rawale SV, Sun Y, Kazanji M, Kaumaya PT (2004) De novo design of peptide immunogens that mimic the coiled coil region of human T-ceU leukemia virus type-1 glycoprotein 21 transmembrane subunit for induction of native protein reactive neutralizing antibodies. J Biol Chem 279 24141-24151. 

Whichever model one favors, it is important to note that peptide immunogens do not have the same possibility for induced fit that occurs in systems with a limited number of receptors (i.e., peptide hormones) because the immune system is a system of diversity, and unless other factors pertain (see below), fixing the correct conformation would seem to have no better probability than fixing the incorrect one. 

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