Vaccine 25 (2007) 1789–1797 Enhanced protection against Streptococcus pyogenes infection by intranasal vaccination with a dual antigen component M protein/SfbI lipid core peptide vaccine formulation C. Olive a,∗,1 , K. Schulze b,1 , H. Kuo Sun a , T. Ebensen b , A. Horv´ ath c,d , I. Toth c,d , C.A. Guzman b a Cooperative Research Centre for Vaccine Technology, Division of Infectious Diseases and Immunology, The Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Queensland 4029, Australia b Department of Vaccinology, Helmholtz Centre for Infection Research, Braunschweig, Germany c The School of Molecular and Microbial Sciences, University of Queensland, Brisbane, Queensland 4067, Australia d The School of Pharmacy, University of Queensland, Brisbane, Queensland 4067, Australia Received 16 March 2006; received in revised form 26 October 2006; accepted 13 November 2006 Available online 30 November 2006 Abstract We investigated the efficacy of a synthetic Streptococcus pyogenes vaccine targeting two virulence factors using the Lipid Core Peptide (LCP) delivery system. BALB/c mice were immunised intranasally with LCPs containing peptides encompassing T-cell and B-cell epitopes of the conserved C-repeat region of the M protein (J8) or the fibronectin-binding repeats region (FNBR) of SfbI, or a combination formulation containing peptides representing both antigens. LCPs were co-administered with the TLR2/6 agonist MALP-2 as mucosal adjuvant. Humoral and cellular immune responses stimulated at systemic and mucosal levels were strongest in mice immunised with the dual antigen formulation. Mice were completely protected following a respiratory challenge with a lethal dose of a heterologous S. pyogenes strain, whereas there was 70% and 90% survival in mice immunised with LCP-J8 and LCP-FNBR, respectively. This is the first report demonstrating the elicitation of better protective immunity by a dual antigen component S. pyogenes vaccine. © 2006 Elsevier Ltd. All rights reserved. Keywords: Streptococcus pyogenes; Lipid core peptide system; Peptide-based vaccines 1. Introduction Infection with Streptococcus pyogenes can cause a wide variety of clinical complications and diseases including tonsillitis, scarlet fever, sepsis, toxic shock syndrome and necrotizing fasciitis, as well as the post-streptococcal autoim- mune diseases, like rheumatic fever and rheumatic heart disease [1]. A primary portal of entry of S. pyogenes is by ∗ Corresponding author at: Cooperative Research Centre for Vaccine Tech- nology, The Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Queensland 4029, Australia. Tel.: +61 7 3362 0431; fax: +61 7 3845 3507. E-mail address: Colleen.OliveO@qimr.edu.au (C. Olive). 1 C. Olive and K. Schulze equally contributed to this work. the mucosal surfaces of the upper respiratory tract, which leads to bacterial adhesion and colonisation of host epithelial cells—a prerequisite to local and disseminated infection [2]. Vaccination by the mucosal route to prevent colonisation and infection is therefore a logical approach in the prevention of diseases caused by S. pyogenes. To date, the bacterial surface M protein has been widely studied as a vaccine candidate against S. pyogenes. The M protein has been shown to be important in host cell adherence and also prevents bacterial clearance by complement-mediated phagocytosis [3,4]. It consists of a highly variable amino-terminal region, which defines the S. pyogenes serotype, and a highly conserved carboxy-terminal C-repeat region [5]. One strategy to develop a broad strain coverage S. pyogenes vaccine is the design of vaccines based 0264-410X/$ – see front matter © 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.vaccine.2006.11.031