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Martín C, Etxaniz A, Uribe KB, Etxebarria A, González-Bullón D, Arlucea J, Goñi FM, Aréchaga J, Ostolaza H. Adenylate Cyclase Toxin promotes bacterial internalisation into non phagocytic cells. Sci Rep 2015; 5:13774. [PMID: 26346097 PMCID: PMC4642564 DOI: 10.1038/srep13774] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 08/04/2015] [Indexed: 02/07/2023] Open
Abstract
Bordetella pertussis causes whooping cough, a respiratory infectious disease that is the fifth largest cause of vaccine-preventable death in infants. Though historically considered an extracellular pathogen, this bacterium has been detected both in vitro and in vivo inside phagocytic and non-phagocytic cells. However the precise mechanism used by B. pertussis for cell entry, or the putative bacterial factors involved, are not fully elucidated. Here we find that adenylate cyclase toxin (ACT), one of the important toxins of B. pertussis, is sufficient to promote bacterial internalisation into non-phagocytic cells. After characterization of the entry route we show that uptake of "toxin-coated bacteria" proceeds via a clathrin-independent, caveolae-dependent entry pathway, allowing the internalised bacteria to survive within the cells. Intracellular bacteria were found inside non-acidic endosomes with high sphingomyelin and cholesterol content, or "free" in the cytosol of the invaded cells, suggesting that the ACT-induced bacterial uptake may not proceed through formation of late endolysosomes. Activation of Tyr kinases and toxin-induced Ca(2+)-influx are essential for the entry process. We hypothesize that B. pertussis might use ACT to activate the endocytic machinery of non-phagocytic cells and gain entry into these cells, in this way evading the host immune system.
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Affiliation(s)
- César Martín
- Departamento de Bioquímica y Biología Molecular and Unidad de Biofísica (CSIC, UPV/EHU), Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
| | - Asier Etxaniz
- Departamento de Bioquímica y Biología Molecular and Unidad de Biofísica (CSIC, UPV/EHU), Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
| | - Kepa B. Uribe
- Departamento de Bioquímica y Biología Molecular and Unidad de Biofísica (CSIC, UPV/EHU), Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
| | - Aitor Etxebarria
- Departamento de Bioquímica y Biología Molecular and Unidad de Biofísica (CSIC, UPV/EHU), Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
| | - David González-Bullón
- Departamento de Bioquímica y Biología Molecular and Unidad de Biofísica (CSIC, UPV/EHU), Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
| | - Jon Arlucea
- Departamento de Biología Celular, Facultad de Medicina, Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain
| | - Félix M. Goñi
- Departamento de Bioquímica y Biología Molecular and Unidad de Biofísica (CSIC, UPV/EHU), Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
| | - Juan Aréchaga
- Departamento de Biología Celular, Facultad de Medicina, Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain
| | - Helena Ostolaza
- Departamento de Bioquímica y Biología Molecular and Unidad de Biofísica (CSIC, UPV/EHU), Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
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Lamberti Y, Gorgojo J, Massillo C, Rodriguez ME. Bordetella pertussis entry into respiratory epithelial cells and intracellular survival. Pathog Dis 2013; 69:194-204. [PMID: 23893966 DOI: 10.1111/2049-632x.12072] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 06/28/2013] [Accepted: 07/18/2013] [Indexed: 01/06/2023] Open
Abstract
Bordetella pertussis is the causative agent of pertussis, aka whooping cough. Although generally considered an extracellular pathogen, this bacterium has been found inside respiratory epithelial cells, which might represent a survival strategy inside the host. Relatively little is known, however, about the mechanism of internalization and the fate of B. pertussis inside the epithelia. We show here that B. pertussis is able to enter those cells by a mechanism dependent on microtubule assembly, lipid raft integrity, and the activation of a tyrosine-kinase-mediated signaling. Once inside the cell, a significant proportion of the intracellular bacteria evade phagolysosomal fusion and remain viable in nonacidic lysosome-associated membrane-protein-1-negative compartments. In addition, intracellular B. pertussis was found able to repopulate the extracellular environment after complete elimination of the extracellular bacteria with polymyxin B. Taken together, these data suggest that B. pertussis is able to survive within respiratory epithelial cells and by this means potentially contribute to host immune system evasion.
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Affiliation(s)
- Yanina Lamberti
- CINDEFI (UNLP CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
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Souza MCD, Santos LSD, Gomes DLR, Sabbadini PS, Santos CSD, Camello TCF, Asad LMBO, Rosa ACDP, Nagao PE, Hirata Júnior R, Guaraldi ALDM. Aggregative adherent strains of Corynebacterium pseudodiphtheriticum enter and survive within HEp-2 epithelial cells. Mem Inst Oswaldo Cruz 2013; 107:486-93. [PMID: 22666859 DOI: 10.1590/s0074-02762012000400008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 02/15/2012] [Indexed: 11/21/2022] Open
Abstract
Corynebacterium pseudodiphtheriticum is a well-known human pathogen that mainly causes respiratory disease and is associated with high mortality in compromised hosts. Little is known about the virulence factors and pathogenesis of C. pseudodiphtheriticum. In this study, cultured human epithelial (HEp-2) cells were used to analyse the adherence pattern, internalisation and intracellular survival of the ATCC 10700 type strain and two additional clinical isolates. These microorganisms exhibited an aggregative adherence-like pattern to HEp-2 cells characterised by clumps of bacteria with a "stacked-brick" appearance. The differences in the ability of these microorganisms to invade and survive within HEp-2 cells and replicate in the extracellular environment up to 24 h post infection were evaluated. The fluorescent actin staining test demonstrated that actin polymerisation is involved in the internalisation of the C. pseudodiphtheriticum strains. The depolymerisation of microfilaments by cytochalasin E significantly reduced the internalisation of C. pseudodiphtheriticum by HEp-2 cells. Bacterial internalisation and cytoskeletal rearrangement seemed to be partially triggered by the activation of tyrosine kinase activity. Although C. pseudodiphtheriticum strains did not demonstrate an ability to replicate intracellularly, HEp-2 cells were unable to fully clear the pathogen within 24 h. These characteristics may explain how some C. pseudodiphtheriticum strains cause severe infection in human patients.
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Affiliation(s)
- Monica Cristina de Souza
- Laboratório de Difteria e Corinebacterias de Importância Clínica, Instituto de Biologia Roberto Alcântara Gomes, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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