Gonzales Júlia Cunha, Gomes Carolina Nogueira, Campioni Fábio, Rodrigues Dália Dos Prazeres, Tonani Ludmilla, Paziani Mário Henrique, Kress Márcia Regina von Zeska, da Silva Paulo, Falcão Juliana Pfrimer
Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo- USP, Avenida Avenida do Café, s/n- Bloco S, sala 41, Ribeirão Preto- São Paulo, CEP 14040- 903, Brazil.
Fundação Oswaldo Cruz, Av. Brasil, Rio de Janeiro, 4365, CEP: 21040-900, Manguinhos, Brazil.
Braz J Microbiol. 2025 Sep;56(3):1755-1764. doi: 10.1007/s42770-025-01741-7. Epub 2025 Jul 27.
Shigellosis is a serious public health problem worldwide caused by Shigella spp. The aims of this study were to molecularly and phenotypically characterize 50 S. flexneri strains isolated from human feces between 1983 and 2017 in different States of Brazil. The pathogenic potential of the strains studied was verified by the ability of the strains to invade human gut epithelial cells (Caco-2), as well as to survive in human macrophages (U-937). The virulence of eight S. flexneri strains, representative of the decades analyzed, was evaluated using the Galleria mellonella infection model. The phylogeny of the 50 strains was verified by Multilocus Sequence Typing (MLST). The percentage of invasion in Caco-2 cells was ≥ 40% and survival in U-937 was ≥ 60% for all 50 S. flexneri strains. Seven of the eight S. flexneri strains caused the death of more than 50% of the Galleria mellonella larvae. All 50 strains were typed as ST245 by MLST. In conclusion, the percentage of cell invasion, macrophage survival and G. mellonella mortality by the strains studied highlighted their pathogenic potential and virulence. The MLST result suggested the presence of phylogenetically related S. flexneri strains circulating in Brazil.
志贺氏菌病是由志贺氏菌属引起的一个全球性严重公共卫生问题。本研究的目的是对1983年至2017年间从巴西不同州的人类粪便中分离出的50株福氏志贺氏菌进行分子和表型特征分析。通过菌株侵入人肠道上皮细胞（Caco-2）的能力以及在人巨噬细胞（U-937）中存活的能力，验证了所研究菌株的致病潜力。使用大蜡螟感染模型评估了代表所分析几十年的8株福氏志贺氏菌的毒力。通过多位点序列分型（MLST）验证了50株菌株的系统发育。所有50株福氏志贺氏菌在Caco-2细胞中的侵袭率≥40%，在U-937中的存活率≥60%。8株福氏志贺氏菌中有7株导致超过50%的大蜡螟幼虫死亡。通过MLST将所有50株菌株分型为ST245。总之，所研究菌株的细胞侵袭率、巨噬细胞存活率和大蜡螟死亡率突出了它们的致病潜力和毒力。MLST结果表明在巴西存在系统发育相关的福氏志贺氏菌菌株在传播。
