02950nas a2200481 4500000000100000008004100001260001300042653002400055653001200079653002300091653002300114653002100137653001700158653002100175653003100196653001100227653001200238653002200250653000900272653002300281653002400304653003900328653002500367653001700392653001300409653002200422653002500444100001200469700001900481700001500500700002100515700001500536700001100551700001600562700001600578700001500594700001900609245017500628300001200803490000700815520163200822022001402454 2013 d c2013 Jul10aAdhesins, Bacterial10aAnimals10aBacterial Adhesion10aBacterial Proteins10aCell Line, Tumor10aCytoskeleton10aEpithelial Cells10aHost-Pathogen Interactions10aHumans10aleprosy10aMass Spectrometry10aMice10aMice, Inbred C57BL10aMicrobial Viability10aMicroscopy, Electron, Transmission10aMycobacterium leprae10aPhagocytosis10aProteome10aPulmonary Alveoli10aRecombinant Proteins1 aSilva C1 aDanelishvili L1 aMcNamara M1 aBerrĂªdo-Pinho M1 aBildfell R1 aBiet F1 aRodrigues L1 aOliveira AV1 aBermudez L1 aPessolani MC V00aInteraction of Mycobacterium leprae with human airway epithelial cells: adherence, entry, survival, and identification of potential adhesins by surface proteome analysis. a2645-590 v813 a

This study examined the in vitro interaction between Mycobacterium leprae, the causative agent of leprosy, and human alveolar and nasal epithelial cells, demonstrating that M. leprae can enter both cell types and that both are capable of sustaining bacterial survival. Moreover, delivery of M. leprae to the nasal septum of mice resulted in macrophage and epithelial cell infection in the lung tissue, sustaining the idea that the airways constitute an important M. leprae entry route into the human body. Since critical aspects in understanding the mechanisms of infection are the identification and characterization of the adhesins involved in pathogen-host cell interaction, the nude mouse-derived M. leprae cell surface-exposed proteome was studied to uncover potentially relevant adhesin candidates. A total of 279 cell surface-exposed proteins were identified based on selective biotinylation, streptavidin-affinity purification, and shotgun mass spectrometry; 11 of those proteins have been previously described as potential adhesins. In vitro assays with the recombinant forms of the histone-like protein (Hlp) and the heparin-binding hemagglutinin (HBHA), considered to be major mycobacterial adhesins, confirmed their capacity to promote bacterial attachment to epithelial cells. Taking our data together, they suggest that the airway epithelium may act as a reservoir and/or portal of entry for M. leprae in humans. Moreover, our report sheds light on the potentially critical adhesins involved in M. leprae-epithelial cell interaction that may be useful in designing more effective tools for leprosy control.

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