Study of gene expression in Nile tilapia (Oreochromis niloticus) vaccinated against pathogen bacteria

• Grant number: 19/07683-2
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: September 01, 2019
• End date: December 31, 2019
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Maria José Tavares Ranzani de Paiva
• Grantee: Said Ben Hamed
• Supervisor: Miguel Angel Moriñigo Gutierrez
• Host Institution: Instituto de Pesca. Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). São Paulo , SP, Brazil
• Institution abroad: Universidad de Málaga (UMA), Spain
• Associated to the scholarship: 16/19816-9 - Mono and trivalent vaccines of pathogenic bacteria Aeromonas hydrophila, Streptococcus agalactiae e Francisella noatunensis subsp. orientalis to Nile Tilapia, BP.PD

Abstract

In aquaculture, resolving disease problems with antibiotic-medicated food is a general practice but has led to antibiotic resistance of several pathogens, resulting in a higher dose requirement for effective control, a matter of increasing public concern. Vaccines for fish are urgently needed to control emergent diseases and prevent the spread of antibiotic and drug-resistant bacteria. Developed for the induction of the immune system for long period prevention, the vaccine regulated (up-regulate or down-regulate) the expression of genes related to the cell-mediated cytotoxicity (CMC; TNF ±), the inflammatory pathway (Il²), the heat chock proteins (HSPs) and the Complement component 8² (C8²). In this project we are using a whole cell-formalin killed of three pathogen bacteria to develop a monovalent and polyvalent vaccine for tilapia. The three pathogen bacteria Francisella noatunensis orientalis, Streptococcus agalactae and Aeromonas hydrophila were isolated from Brazilian farms that had acute diseases outbreak. We used the Montanide ISA 763A VG as an adjuvant in the vaccine preparation. Survival of the vaccinated fishes were evaluated after challenge with virulent bacteria cited above. Blood and samples of organs (liver and spleen) were collected after one week and 3 weeks post-challenge. Evaluation of the efficiency of the developed vaccine is being realized via determination of Relative Percent Survival (RPS), execution of a complete hemogramme, checks of the bactericidal activity of the serum and gene expression of the genes: Tumor necrosis factor (TNF ±), Interleukin 1-beta (Il²), heat shock proteins (HSP70) and Complement component 8² (C8²). The evaluation of the regulation of these genes will be realized in comparison with two housekeeping genes ef1± and GAPDH.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BEN HAMED, SAID; TERESA TAPIA-PANIAGUA, SILVANA; ANGEL MORINIGO, MIGUEL; TAVARES RANZANI-PAIVA, MARIA JOSE. Advances in vaccines developed for bacterial fish diseases, performance and limits. AQUACULTURE RESEARCH, v. 52, n. 6, FEB 2021. (19/07683-2, 18/06012-4, 16/19816-9)