Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2007-2-7
pubmed:abstractText
Guinea pigs are highly susceptible to Legionella pneumophila infection and therefore have been the preferred animal model for studies of legionellosis. In this study guinea pig infections revealed that the Legionella virulence factor Mip (macrophage infectivity potentiator) contributes to the bacterial dissemination within the lung tissue and the spread of Legionella to the spleen. Histopathology of infected animals, binding assays with components of the extracellular matrix (ECM), bacterial transmigration experiments across an artificial lung epithelium barrier, inhibitor studies and ECM degradation assays were used to elucidate the underlying mechanism of the in vivo observation. The Mip protein, which belongs to the enzyme family of FK506-binding proteins (FKBP), was shown to bind to the ECM protein collagen (type I, II, III, IV, V, VI). Transwell assays with L. pneumophila and recombinant Escherichia coli HB101 strains revealed that Mip enables these bacteria to transmigrate across a barrier of NCI-H292 lung epithelial cells and ECM (NCI-H292/ECM barrier). Mip-specific monoclonal antibodies and the immunosuppressants rapamycin and FK506, which inhibit the peptidyl prolyl cis/trans isomerase (PPIase) activity of Mip, were able to inhibit this transmigration. By using protease inhibitors we found that the penetration of the NCI-H292/ECM barrier additionally requires a serine protease activity. Degradation assays with (35)S-labelled ECM proteins supported the finding of a concerted action of Mip and a serine protease. The described synergism between the activity of the collagen binding Mip protein and the serine protease activity represents an entirely new mechanism for bacterial penetration of the lung epithelial barrier and has implications for other prokaryotic and eukaryotic pathogens.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1462-5814
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
450-62
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Collagen binding protein Mip enables Legionella pneumophila to transmigrate through a barrier of NCI-H292 lung epithelial cells and extracellular matrix.
pubmed:affiliation
Institut für Molekulare Infektionsbiologie, Universität Würzburg, Röntgenring 11, D-97070 Würzburg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't