Branched and linear lipopeptide vaccines have different effects on primary CD4 super(+) and CD8 super(+) T-cell activation but induce similar tumor- protective memory CD8 super(+) T-cell responses

• Published in: Vaccine Vol. 26; no. 21; pp. 2570 - 2579
• Main Authors: Baz, Adriana, Buttigieg, Kathy, Zeng, Weiguang, Rizkalla, Michael, Jackson, David C, Groves, Penny, Kelso, Anne
• Format: Journal Article
• Language: English
• Published: 01.05.2008
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2008.03.022

We compared murine T-cell responses to synthetic lipopeptide vaccines in which the TLR2 ligand Pam sub(2)Cys was attached to co-linear CD4 super(+) and CD8 super(+) T-cell epitopes of ovalbumin (OVA) in a linear or branched configuration. Mice received OVA-specific transgenic CD8 super(+) and CD4 super(+) T- cells followed by one injection of vaccine. Although the branched lipopeptide was more potent in activating OVA-specific CD4 super(+) and CD8 super(+) T-cells in the primary response, both vaccines induced cytolytic T lymphocytes (CTL) that expressed perforin, granzyme A-C, and IFN- gamma mRNAs and conferred long- term protection of most mice against challenge with OVA-expressing tumor cells. OVA epitope display was reduced in tumors that developed in some mice, suggesting CD8 super(+) T-cell dependent selection.