Molecular characterization of secreted proteins of Schistosoma mansoni VAL (Venom Allergen-Like Protein) family and evaluation as vaccine candidates.

Author(s)

Rafaela Sachetto Fernandes

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2016-03-02

Examining board members

Luciana Cezar de Cerqueira Leite; José Gregorio Cabrera Gomez; Roxane Maria Fontes Piazza; Carlos Eduardo Winter; Gerhard Wunderlich

• Advisor: Luciana Cezar de Cerqueira Leite

Abstract

Schistosomiasis is a disease caused by trematodes of the genus Schistosoma. Among the genes identified in the parasite transcriptome, members of SmVAL (Schistosoma mansoni Venom Allergen-Like) gene family were proposed as vaccine candidates. SmVALs were identified in cercariae and schistosomule secretions in vitro, the SmVAL4 and 24 transcripts were located to the germ ball acetabular glands and SmVAL4 native protein was identified in cercariae extract, indicating functions in skin penetration. On the other hand, SmVAL13 and 14 transcripts were located to the anterior esophageal gland of adult worms, suggesting roles in the blood feeding processes. Immunization with rSmVAL4, 6, 7, 13, 14 and 18 proteins co-administered did not protected mice against experimental challenge, however, there was a decrease in the number of females and the number of eggs in the immunized group. The investigation of functions for secreted proteins showed that rSmVAL18 interacts with plasminogen in vitro thus favoring the host invasion. (AU)

• FAPESP's process: 10/18486-9 - Molecular characterization and immunological evaluation of VAL (Venom Allergen-Like protein) protein family from Schistosoma mansoni
• Grantee: Rafaela Sachetto Fernandes
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)