Phagocytotic activity and gene expression of leukocytes isolated from Astyanax lacustris

Author(s)

N. Levy-Pereira ^[1] ; M. M. Carriero ^[2] ; S. R. L. Maganha ^[3] ; C. M. Meira ^[4] ; T. M. Lázaro ^[5] ; N. R. A. Rocha ^[6] ; A. A. M. Maia ^[7] ; G. Wiegertjes ^[8] ; A. M. Fernandes ^[9] ; R. L. M. Sousa ^[10]

Affiliation

^[1] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Higiene Zootécnica - Brasil

^[2] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Parasitologia - Brasil

^[3] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Higiene Zootécnica - Brasil

^[4] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Parasitologia - Brasil

^[5] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Higiene Zootécnica - Brasil

^[6] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Higiene Zootécnica - Brasil

^[7] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Parasitologia - Brasil

^[8] Wageningen University & Research. Department of Animal Sciences. Cell Biology and Immunology Group - Holanda

^[9] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório Multi-usuário de Microbiologia - Brasil

^[10] Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária, Laboratório de Higiene Zootécnica - Brasil

• Document type: Journal article
• Source: Brazilian Journal of Biology; v. 83, 2023-01-16.

Abstract

Abstract The constant intensification of aquaculture has considerable increased the stress levels of farmed fish and, consequently, the number and intensity of diseases outbreaks. Thus, studies on fish immune response, especially regarding the interaction of fish leukocytes with potential pathogens and xenobiotics are of great importance in order to develop new prophylactic and curative strategies. We isolated leukocytes from the head kidney of Astyanax lacustris—an important Neotropical fish species for aquaculture and a potential model for Neotropical aquaculture research—using a Percoll centrifugation protocol. The isolated leukocytes were incubated with lipopolysaccharide (LPS), and the expression of genes IL-1β, IL-8, LysC, and LysG were measured. We assessed the phagocytotic activity of leukocytes using Congo red-dyed yeast, a novel and cost-effective protocol that has been developed in this study. The isolated leukocytes responded to LPS induction, exhibiting strong IL-1β and IL-8 upregulation, two of the most important pro-inflammatory interleukins for vertebrates immune reponse. The optimal concentration of yeast for the phagocytic assay was 106 cells mL-1, resulting in acceptable phagocytic capacity (PC) but without excess of yeasts during the counting process, ensuring a high precision and accuracy of the method. To the best of our knowledge, the present study is the first to investigate the in vitro gene expression and phagocytic activity of leukocytes isolated from A. lacustris. Our findings will serve as a reference for future studies on the immunology and toxicology of Neotropical fish. (AU)

• FAPESP's process: 20/06371-4 - Effect of immunization of lambaris (Astyanax altiparanae) with the immobilization antigen IAG52A from Ichthyophthirius multifiliis associated with the cytokine IL-8 from A. altiparanae as a molecular adjuvant
• Grantee: Caroline Munhoz Meira
• Support Opportunities: Scholarships in Brazil - Master