TY - JOUR

T1 - Immunological and bacteriological shifts associated with a flagellin-hyperproducing Salmonella Enteritidis mutant in chickens

AU - de Oliveira Barbosa, Fernanda

AU - de Freitas Neto, Oliveiro Caetano

AU - Rodrigues Alves, Lucas Bocchini

AU - Benevides, Valdinete Pereira

AU - de Souza, Andrei Itajahy Secundo

AU - da Silva Rubio, Marcela

AU - de Almeida, Adriana Maria

AU - Saraiva, Mauro Mesquita

AU - de Oliveira, Celso José Bruno

AU - Olsen, John Elmerdahl

AU - Junior, Angelo Berchieri

PY - 2021

Y1 - 2021

N2 - Salmonella Enteritidis causes infections in humans and animals which are often associated with extensive gut colonization and bacterial shedding in faeces. The natural presence of flagella in Salmonella enterica has been shown to be enough to induce pro-inflammatory responses in the gut, resulting in recruitment of polymorphonuclear cells, gut inflammation and, consequently, reducing the severity of systemic infection in chickens. On the other hand, the absence of flagellin in some Salmonella strains favours systemic infection as a result of the poor intestinal inflammatory responses elicited. The hypothesis that higher production of flagellin by certain Salmonella enterica strains could lead to an even more immunogenic and less pathogenic strain for chickens was here investigated. In the present study, a Salmonella Enteritidis mutant strain harbouring deletions in clpP and fliD genes (SE ΔclpPfliD), which lead to overexpression of flagellin, was generated, and its immunogenicity and pathogenicity were comparatively assessed to the wild type in chickens. Our results showed that SE ΔclpPfliD elicited more intense immune responses in the gut during early stages of infection than the wild type did, and that this correlated with earlier intestinal and systemic clearance of the bacterium.

AB - Salmonella Enteritidis causes infections in humans and animals which are often associated with extensive gut colonization and bacterial shedding in faeces. The natural presence of flagella in Salmonella enterica has been shown to be enough to induce pro-inflammatory responses in the gut, resulting in recruitment of polymorphonuclear cells, gut inflammation and, consequently, reducing the severity of systemic infection in chickens. On the other hand, the absence of flagellin in some Salmonella strains favours systemic infection as a result of the poor intestinal inflammatory responses elicited. The hypothesis that higher production of flagellin by certain Salmonella enterica strains could lead to an even more immunogenic and less pathogenic strain for chickens was here investigated. In the present study, a Salmonella Enteritidis mutant strain harbouring deletions in clpP and fliD genes (SE ΔclpPfliD), which lead to overexpression of flagellin, was generated, and its immunogenicity and pathogenicity were comparatively assessed to the wild type in chickens. Our results showed that SE ΔclpPfliD elicited more intense immune responses in the gut during early stages of infection than the wild type did, and that this correlated with earlier intestinal and systemic clearance of the bacterium.

KW - Deletion

KW - Flagellin

KW - Mutant

KW - Poultry

KW - Salmonellosis

U2 - 10.1007/s42770-020-00399-7

DO - 10.1007/s42770-020-00399-7

M3 - Journal article

C2 - 33150477

AN - SCOPUS:85094980481

VL - 52

SP - 419

EP - 429

JO - Brazilian Journal of Microbiology

JF - Brazilian Journal of Microbiology

SN - 1517-8382

ER -