Title Salmonella Typhimurium ST313 isolated in Brazil revealed to be more invasive and inflammatory in murine colon compared to ST19 strains
Author Amanda Aparecida Seribelli1†, Tamara R. Machado Ribeiro2†, Patrick da Silva2†, Isabela Mancini Martins2, Felipe Pinheiro Vilela1, Marta I. Cazentini Medeiros3, Kamila Chagas Peronni4, Wilson Araújo da Silva Junior4,5, Cristiano Gallina Moreira2*, and Juliana Pfrimer Falcão1*
Address 1School of Pharmaceutical Sciences of Ribeirão Preto - University of São Paulo, Ribeirão Preto, São Paulo 05508-220, Brazil, 2Department of Biological Sciences, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, São Paulo 01049-010, Brazil, 3Adolfo Lutz Institute - Ribeirão Preto, São Paulo 14085-410, Brazil, 4Regional Blood Center of the University Hospital of the Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, São Paulo 05508-220, Brazil, 5Ribeirão Preto Medical School, Genetics Department - University of São Paulo, Ribeirão Preto, São Paulo 05508-220, Brazil
Bibliography Journal of Microbiology, 59(9),861-870, 2021,
DOI 10.1007/s12275-021-1082-z
Key Words Salmonella Typhimurium ST313, invasion, inflammation, cytokines, RNA-seq
Abstract Salmonella Typhimurium (ST313) has caused an epidemic of invasive disease in sub-Saharan Africa and has been recently identified in Brazil. As the virulence of this ST is poorly understood, the present study aimed to (i) perform the RNAseq in vitro of S. Typhimurium STm30 (ST313) grown in Luria-Bertani medium at 37°C; (ii) compare it with the RNAseq of the S. Typhimurium SL1344 (ST19) and S. Typhimurium STm11 (ST19) strains under the same growing conditions; and (iii) examine the colonization capacity and expression of virulence genes and cytokines in murine colon. The STm30 (ST313) strain exhibited stronger virulence and was associated with a more inflammatory profile than the strains SL1344 (ST19) and STm11 (ST19), as demonstrated by transcriptome and in vivo assay. The expression levels of the hilA, sopD2, pipB, and ssaS virulence genes, other Salmonella pathogenicity islands SPI-1 and SPI-2 genes or effectors, and genes of the cytokines IL-1β, IFN-γ, TNF-α, IL-6, IL-17, IL-22, and IL-12 were increased during ST313 infection in C57BL/6J mice. In conclusion, S. Typhimurium STm30 (ST313) isolated from human feces in Brazil express higher levels of pathogenesis- related genes at 37°C and has stronger colonization and invasion capacity in murine colon due to its high expression levels of virulence genes, when compared with the S. Typhimurium SL1344 (ST19) and STm11 (ST19) strains. STm30 (ST313) also induces stronger expression of pro-inflammatory cytokines in this organ, suggesting that it causes more extensive tissue damage.