Towards an immunosense vaccine to prevent toxoplasmosis: Protective Toxoplasma gondii epitopes restricted by HLA-A*0201

Vaccine. 2010 Nov 20. [Epub ahead of print]

Towards an immunosense vaccine to prevent toxoplasmosis: Protective Toxoplasma gondii epitopes restricted by HLA-A*0201

Cong H, Mui EJ, Witola WH, Sidney J, Alexander J, Sette A, Maewal A, McLeod R.

Department of Surgery, The University of Chicago, 5841 S. Maryland Ave., MC 2114, Chicago, IL 60637, USA.

Abstract
The ideal vaccine to protect against toxoplasmosis in humans would include antigens that elicit a protective T helper cell type 1 immune response, and generate long-lived IFN-γ-producing CD8(+) T cells. Herein, we utilized a predictive algorithm to identify candidate HLA-A02 supertype epitopes from Toxoplasma gondii proteins. Thirteen peptides elicited production of IFN-γ from PBMC of HLA-A02 supertype persons seropositive for T. gondii infection but not from seronegative controls. These peptides displayed high-affinity binding to HLA-A02 proteins. Immunization of HLA-A*0201 transgenic mice with these pooled peptides, with a universal CD4(+) epitope peptide called PADRE, formulated with adjuvant GLA-SE, induced CD8(+) T cell IFN-γ production and protected against parasite challenge. Peptides identified in this study provide candidates for inclusion in immunosense epitope-based vaccines.

Copyright © 2010. Published by Elsevier Ltd.
PMID: 21095258 [PubMed - as supplied by publisher]