Data/hora: 05/06/2024 06:31:26

Provedor de dados: 	55	
País: 	Brazil	
Título: 	Salmonella enterica serovar Typhi plasmid pR ST98 enhances intracellular bacterial growth and S. typhi-induced macrophage cell death by suppressing autophagy	
Autores: 	He,Peiyan; Wu,Shuyan; Chu,Yuanyuan; Yang,Yanru; Li,Yuanyuan; Huang,Rui.	
Data: 	2012-06-01	
Ano: 	2012	
Palavras-chave: 	Plasmid pR ST98; Macrophage; Autophagy; Intracellular bacterial growth; Cell death.	
Resumo: 	OBJECTIVES: Plasmid pR ST98 is a hybrid resistance-virulence plasmid isolated from Salmonella enterica serovar Typhi (S. typhi). Previous studies demonstrated that pR ST98 could enhance the virulence of its host bacteria. However, the mechanism of pR ST98-increased bacterial virulence is still not fully elucidated. This study was designed to gain further insight into the roles of pR ST98 in host responses. METHODS: Human-derived macrophage-like cell line THP-1 was infected with wild-type (ST8), pR ST98-deletion (ST8-ΔpR ST98), and complemented (ST8-c-pR ST98) S. typhi strains. Macrophage autophagy was performed by extracting the membrane-unbound LC3-I protein from cells, followed by flow cytometric detection of the membrane-associated fraction of LC3-II. Intracellular bacterial growth was determined by colony-forming units (cfu) assay. Macrophage cell death was measured by flow cytometry after propidium iodide (PI) staining. Autophagy activator rapamycin (RAPA) was added to the medium 2 h before infection to investigate the effect of autophagy on intracellular bacterial growth and macrophage cell death after S. typhi infection. RESULTS: Plasmid pR ST98 suppressed autophagy in infected macrophages and enhanced intracellular bacterial growth and S. typhi-induced macrophage cell death. Pretreatment with RAPA effectively restricted intracellular bacterial growth of ST8 and ST8-c-pR ST98, and alleviated ST8 and ST8-c-pR ST98-induced macrophage cell death, but had no significant effect on ST8-ΔpR ST98. CONCLUSIONS: Plasmid pR ST98 enhances intracellular bacterial growth and S. typhi-induced macrophage cell death by suppressing autophagy.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702012000300008	
Editor: 	Brazilian Society of Infectious Diseases	
Relação: 	10.1590/S1413-86702012000300008	
Formato: 	text/html	
Fonte: 	Brazilian Journal of Infectious Diseases  v.16 n.3 2012	
Fonte: 	info:eu-repo/semantics/openAccess