Journal of Clinical and Cellular Immunology
Open Access

High therapeutic efficacy of a new survivin LSP-Cancer vaccine containing CD⁴⁺ and CD⁸⁺T-Cell epitopes

Joint Event on 36^th Euro Global Summit and Expo on Vaccines & Vaccination & 6^th World Congress and Exhibition on Antibiotics and Antibiotic Resistance

June 03-04, 2019 London, UK

Ahmed Bouzidi

Vaxeal Holding SA, Switzerland

Posters & Accepted Abstracts: J Clin Cell Immunol

Abstract :

The tumor antigen survivin is an attractive target to develop therapeutic cancer vaccines because of its restricted overexpression and vital functions in most human tumors. Accordingly, several clinical trials targeting survivin in various cancer indications have been conducted. Most of them relied on short peptide-based vaccines and showed promising, but limited clinical results. In this study, we investigated the immunogenicity and therapeutic efficacy of a new long synthetic peptide (LSP)-based cancer vaccine targeting the tumor antigen survivin (SVX). This SVX vaccine is composed of three long synthetic peptides containing several CD⁴⁺ and CD8+ T-cell epitopes, which bind to various HLA class II and class I molecules. Studies in healthy individuals showed CD⁴⁺ and CD⁸⁺ T-cell immunogenicity of SVX peptides in human, irrespective of the individual’s HLA types. Importantly, high frequencies of spontaneous T-cell precursors specific to SVX peptides were also detected in the blood of various cancer patients, demonstrating the absence of tolerance against these peptides. We then demonstrated SVX vaccine’s high therapeutic efficacy against four different established murine tumor models, associated with its capacity to generate both specific cytotoxic CD⁸⁺and multifunctional Th1 CD⁴⁺+ T-cell responses. When tumors were eradicated, generated memory T-cell responses protected against rechallenge allowing longterm protection against relapses. Treatment with SVX vaccine was also found to reshape the tumor microenvironment by increasing the tumor infiltration of both CD⁴⁺ and CD⁸⁺ T cells but not Treg cells therefore tipping the balance toward a highly efficient immune response. These results highlight that this LSP-based SVX vaccine appears as a promising cancer vaccine and warrants its further clinical development.

Biography :

E-mail: abouzidi@vaxeal.net