Research

Epitope definition by proteomic similarity analysis: identification of the linear determinant of the anti-Dsg3 MAb 5H10

Alberta Lucchese¹ , Abraham Mittelman² , Mong-Shang Lin³ , Darja Kanduc⁴ and Animesh A Sinha⁵

¹Department of Odontostomatology and Surgery, Faculty of Medicine, University of Bari, P.za G. Cesare 11, 70124 Bari, Italy

²Department of Medicine, New York Medical College, Valhalla, NY 10595, USA

³Department of Dermatology, Medical College of Wisconsin, Milwaukee 53226, USA

⁴Department of Biochemistry and Molecular Biology, University of Bari, Via Orabona 4, 70126 Bari, Italy

⁵Department of Dermatology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA

author email corresponding author email

Journal of Translational Medicine 2004, 2:43doi:10.1186/1479-5876-2-43

Published:	11 December 2004

Abstract

Background

Walking along disease-associated protein sequences in the search for specific segments able to induce cellular immune response may direct clinical research towards effective peptide-based vaccines. To this aim, we are studying the targets of the immune response in autoimmune diseases by applying the principle of non-self-discrimination as a driving concept in the identification of the autoimmunogenic peptide sequences.

Methods

Computer-assisted proteomic analysis of the autoantigen protein sequence and dot-blot/NMR immunoassays are applied to the prediction and subsequent validation of the epitopic sequences.

Results

Using the experimental model Pemphigus vulgaris/desmoglein 3, we have identified the antigenic linear determinant recognized by MAb 5H10, a monoclonal antibody raised against the extracellular domain of human desmoglein-3. The computer-assisted search for the Dsg3 epitope was conducted by analyzing the similarity level to the mouse proteome of the human desmoglein protein sequence. Dot-blot immunoassay analyses mapped the epitope within the sequence Dsg3_49–60 REWVKFAKPCRE, which shows low similarity to the mouse proteome. NMR spectroscopy analyses confirmed the specificity of MAb 5H10 for the predicted epitope.

Conclusions

This report promotes the concept that low level of sequence similarity to the host's proteome may modulate peptide epitopicity.