Evaluation of protective immune response against fowl typhoid in chickens vaccinated with the attenuated strain Salmonella Gallinarum Delta cobS Delta cbiA

Author(s)

Casarin Penha Filho, Rafael Antonio ; Acelas Diaz, Silvia Juliana ; Medina, Tiago da Silva ; Chang, Yung-Fu ; da Silva, Joao Santana ; Berchieri, Jr., Angelo

• Document type: Journal article
• Source: Research in Veterinary Science; v. 107, p. 220-227, AUG 2016.
• Web of Science Citations: 2

Abstract

Salmonella enterica serovar Gallinarum biovar Gallinarum (SG) causes fowl typhoid in chickens, a septicemic infection which results in high mortality rates. This disease causes high economic impact to the poultry industry worldwide because of the mortality or elimination of positive flocks to control bacterial dissemination. Live vaccines are used in the fields, however the characterization of immune mechanisms important for protection are being studied to improve the efficacy of vaccination schemes. In this study, we evaluated the immune response in brown layer-hens, vaccinated or not, during the most critical period of infection. Cellular and humoral immunity were extensively evaluated until 7 days post-infection (DPI), by flow cytometry and ELISA, respectively. Furthermore, we evaluated the expression of important pro-inflammatory cytokines after infection of bone marrow derived macrophages (BMDMs) with the live attenuated SG vaccine and with the wild SG strain. The results showed an increasing production of IgG and IgM during the first week post-infection, in vaccinated layer-hens, which was absent in unvaccinated birds. The population of CD8(+) CD44(+) and CD4(+)CD44(+) T cells in spleen and cecal tonsils constantly decreased in unvaccinated birds in comparison with vaccinated layers. The expression of IFN-gamma and TNF-alpha. in BMDMs was induced by both SG strains (attenuated and wild) at similar levels (p>0.05). Vaccination with live SG vaccine reduced systemic infection by challenge strain of SG and prevented the mortality rate of 85% that occurred in unvaccinated layer-hens during 30 dpi. Furthermore, the immunization enhanced the proliferation of effector CD4(+) and CD8(+) T cells after challenge. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 13/26127-7 - Factors involved in the pathogenesis of fowl typhoid
• Grantee: Angelo Berchieri Junior
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/24017-7 - Evaluation of the infection and immunity in susceptible and resistant lines of chicken (Gallus gallus) challenged with Salmonella enterica subsp. enterica sorovar Gallinarum
• Grantee: Rafael Antonio Casarin Penha Filho
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/26122-5 - Identification of homologous protein antigen in Salmonella enterica subsp. enterica serovars Typhimurium, Enteritidis, Heidelberg and Schwarzengrund for production of recombinant protein and evaluation as a vaccine candidate in chickens
• Grantee: Rafael Antonio Casarin Penha Filho
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor