Evaluation of the variability of the vaccine candidate PspC (Pneumococcal surface protein C) in Streptococcus pneumoniae isolates from the University Hospital of the University of São Paulo.

Author(s)

Adriana Tonet Moreno

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2013-08-09

Examining board members

Eliane Namie Miyaji; Maria Elisabete Sbrogio de Almeida; Lucila Okuyama Fukasawa; Viviane Maimoni Gonçalves; Elizabeth Angelica Leme Martins

• Advisor: Eliane Namie Miyaji

Abstract

Streptococcus pneumoniae is the causative agent of several diseases, such as meningitis and pneumonia. PspC (Pneumococcal surface protein C) has been described as an important vaccine candidate protein as it could provide wide coverage with low cost of production. PspC is a virulence factor capable of binding to Factor H (FH) and secretory IgA (sIgA). PspC is polymorphic antigen, and therefore it is crucial to evaluate its variability. In the present work we have determined the PspC group of 13 pneumococcal isolates obtained at the University Hospital of the University of São Paulo. Antisera against different PspC groups were produced and PspC group 3 (PspC3) was able to induce antibodies that recognized different groups of PspC. Antibodies to PspC3 reduced binding of FH and sIgA to pneumococcus in in vitro assays. However, no protection was observed against a murine model of nasopharyngeal colonization by immunization with PspC3. This was possibly due to deficiencies in the experimental model. (AU)

• FAPESP's process: 09/16275-3 - Evaluation of the variability of the candidate vaccine PspC (Pneumococcal surface protein C) in isolates of Streptococcus pneumoniae from the University Hospital of the University of São Paulo
• Grantee: Adriana Tonet Moreno
• Support Opportunities: Scholarships in Brazil - Doctorate