Epitope mapping of Streptococcus pneumoniae vaccine antigens PspA (Pneumococcal surface protein A) and PspC (Pneumococal surface protein C).

Author(s)

Cintia Fiuza Marques Vadesilho

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2014-03-17

Examining board members

Eliane Namie Miyaji; Viviane Maimoni Gonçalves; Eliana Faquim de Lima Mauro

• Advisor: Eliane Namie Miyaji

Abstract

S. pneumoniae can cause respiratory tract infections. An alternative to the conjugate vaccines, which confer serotype-specific protection, would be a vaccine based on epitopes of variants of antigens such as PspA and PspC. The objective of this study was to identify epitopes of variants of PspA and PspC, using the peptide array technique, aiming at the synthesis of a multi-epitope antigen. The results obtained with peptide arrays indicated that antibodies against linear epitopes of PspA recognize the initial N-terminal and proline-rich regions, but these epitopes seem to be only markers of exposure to pneumococcus and conformational epitopes would be in fact protective, as observed in the experiments with fragments of 100 amino acids constructed from PspARx1, especially those present in Frags 2 and 4. Linear epitopes of PspC seem to be important in the regions of sIgA and FH binding. Thus, a protein-based vaccine with broad coverage could contain the regions of Frag 2 of PspA and the regions of sIgA and FH binding of PspC. (AU)

• FAPESP's process: 11/13671-5 - Mapping of epitopes present in variants of the Streptococcus pneumoniae vaccine antigens PspA (Pneumococcal surface protein A) and PspC (Pneumococcal surface protein C)
• Grantee: Cintia Fiuza Marques Vadesilho
• Support Opportunities: Scholarships in Brazil - Master