Epitope mapping of monoclonal antibodies generated against PspA (Pneumococcal surface protein A) through phage-display

• Grant number: 13/23722-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2014
• End date: December 31, 2014
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Eliane Namie Miyaji
• Grantee: Tiphanie Kertischka Lemos
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Streptococcus pneumoniae is an important human pathogen, causing severe diseases such as meningitis, pneumonia, bacteremia and sepsis. The currently available vaccines induce anti-capsular polysaccharide antibodies and have some disadvantages, such as limited serotype coverage and high production costs. The widespread use of the 7-valent conjugate polysaccharide vaccine led to a drastic reduction of infections caused by vaccine-serotypes, but there was also a rapid substitution with disease caused by non-vaccine serotypes. The development of alternative vaccines is thus still a priority and new strategies include the development of vaccines based on protein atigens. Among the most promising proteins is PspA (Pneumococcal surface protein A). This project aims at mapping epitopes recognized by monoclonal antibodies generated against PspA. A random peptide comercial library will be screened with the monoclonals. The determination of these epitopes opens up the possibility of using a recombinant protein containing several epitopes of PspA, that could induce broadly reactive antibodies and afford protection against different pneumococcal isolates.