Institute of Tropical Medicine Antwerp
Foundation of Public Utility

Evidence for intramacrophage growth phase of Mycobacterium ulcerans

DSpace/Manakin Repository

Show simple item record Torrado, E. en_US Fraga, A. G. en_US Castro, A. G. en_US Stragier, P. en_US Meyers, W. M. en_US Portaels, F. en_US Silva, M. T. en_US Pedrosa, J. en_US 2007-12-06T14:48:20Z 2007-12-06T14:48:20Z 2007 en_US
dc.identifier.issn 0019-9567 en_US
dc.identifier.other ITG-M4B en_US
dc.identifier.other ITG-M6A en_US
dc.identifier.other MICRO en_US
dc.identifier.other U-MYCOB en_US
dc.identifier.other JIF en_US
dc.identifier.other DOI en_US
dc.identifier.other ABSTRACT en_US
dc.description.abstract Mycobacterium ulcerans is the etiologic agent of Buruli ulcer (BU), an emerging tropical skin disease. Virulent M. ulcerans secretes mycolactone, a cytotoxic exotoxin with a key pathogenic role. M. ulcerans in biopsy specimens has been described as an extracellular bacillus. In vitro assays have suggested a mycolactone-induced inhibition of M. ulcerans uptake by macrophages in which its proliferation has not been demonstrated. Therefore, and uniquely for a mycobacterium, M. ulcerans has been classified as an extracellular pathogen. In specimens from patients and in mouse footpad lesions, extracellular bacilli were concentrated in central necrotic acellular areas; however, we found bacilli within macrophages in surrounding inflammatory infiltrates. We demonstrated that mycolactone-producing M. ulcerans isolates are efficiently phagocytosed by murine macrophages, indicating that the extracellular location of M. ulcerans is not a result of inhibition of phagocytosis. Additionally, we found that M. ulcerans multiplies inside cultured mouse macrophages when low multiplicities of infection are used to prevent early mycolactone-associated cytotoxicity. Following the proliferation phase within macrophages, M. ulcerans induces the lysis of the infected host cells, becoming extracellular. Our data show that M. ulcerans, like M. tuberculosis, is an intracellular parasite with phases of intramacrophage and extracellular multiplication. The occurrence of an intramacrophage phase is in accordance with the development of cell-mediated and delayed-type hypersensitivity responses in BU patients. en_US
dc.language English en_US
dc.subject Mycobacteriology en_US
dc.subject Mycobacterium ulcerans en_US
dc.subject Pathogenesis en_US
dc.subject Multiplication en_US
dc.subject Intracellular en_US
dc.subject Extracellular en_US
dc.subject Macrophages en_US
dc.subject Phagocytosis en_US
dc.title Evidence for intramacrophage growth phase of Mycobacterium ulcerans en_US
dc.type Article en_US
dc.citation.issue 2 en_US
dc.citation.jtitle Infection and Immunity en_US
dc.citation.volume 75 en_US
dc.citation.pages 977-987 en_US
dc.citation.jabbreviation Infect Immun en_US

Files in this item

Files Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record