Zebrafish embryo sensitivity test as in vivo platform to anti-Shiga toxin compound screening

Author(s)

Melo, Bruna de Sousa ^[1] ; Ventura Fernandes, Bianca Helena ^[2] ; Anjos Lopes-Ferreira, Monica Valdyrce ^{[3, 4]} ; Henrique, Camila ^[1] ; Fontes Piazza, Roxane Maria ^[1] ; Luz, Daniela ^{[1, 5]}

Affiliation

^[1] Inst Butantan, Lab Bacteriol, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Lab Controle Genet & Sanit Anim, Unidade Zebrafish, Fac Med, Sao Paulo - Brazil

^[3] Inst Butantan, Lab Especial Toxinol, Sao Paulo - Brazil

^[4] CeTICS FAPESP, Sao Paulo - Brazil

^[5] Univ Fed Sao Paulo, Inst Ciencia & Tecnol, Lab Monoclonais, Rua Talim 330, BR-12231280 Sao Jose Dos Campos, SP - Brazil

• Document type: Journal article
• Source: Brazilian Journal of Microbiology; v. 51, n. 3, p. 1021-1027, SEP 2020.
• Web of Science Citations: 1

Abstract

Shiga toxin-producing Escherichia coli (STEC) pathotype secretes two types of AB(5) cytotoxins (Stx1 and Stx2), responsible for complications such as hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS) in infected patients, which could lead to sequels and death. Currently, there is no effective treatment against the cytotoxic effect of these toxins. However, in order to approve any therapy molecule, an animal experiment is required in order to evaluate the efficacy and safety of therapeutic approaches. The use of alternative small host models is growing among human infectious disease studies, particularly the vertebrate zebrafish model, since relevant results have been described for pathogen-host interaction. In this sense, the present work aimed to analyze the toxic effect of Shiga toxins in zebrafish embryo model in order to standardize this method in the future to be used as a fast, simple, and efficient methodology for the screening of therapeutic molecules. Herein, we demonstrated that the embryos were sensitive in a dose-dependent manner to both Stx toxins, with LD50 of 22 mu g/mL for Stx1 and 33 mu g/mL for Stx2, and the use of anti-Stx polyclonal antibody abolished the toxic effect. Therefore, this methodology can be a rapid alternative method for selecting promising compounds against Stx toxins, such as recombinant antibodies. (AU)

• FAPESP's process: 11/12928-2 - New challenge for the diagnosis of diarrheagenic Escherichia coli: recombinant antibody obtention against different virulence factors
• Grantee: Roxane Maria Fontes Piazza
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/17006-2 - Shiga toxin-producing Escherichia coli (STEC) intoxication and colonization in Zebrafish model: An in vivo alternative for pathogenicity studies and therapeutic antibodies validation
• Grantee: Daniela Luz Hessel da Cunha
• Support Opportunities: Scholarships in Brazil - Post-Doctoral