Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1995-11-8
pubmed:abstractText
The destruction and processing of bacteria by activated macrophages facilitates the presentation of antigens to T cells and thereby promotes the induction of specific immunity. The PhoP-PhoQ regulatory system that controls the synthesis of many Salmonella proteins required for virulence and survival within macrophages is one mechanism that this particular intracellular pathogen has evolved to resist destruction. To address whether the phoP locus also influences antigen processing during the interaction of Salmonella typhimurium with macrophages, we tested the effect of phoP mutations on the processing and presentation of model antigens expressed by the bacteria. Activated macrophages processed phoP- bacteria with greater efficiency than wild-type bacteria, as measured by the response of antigen-specific T-hybridoma cells; Salmonella constitutively expressing PhoP were processed even less efficiently than wild-type Salmonella. After heat-inactivation, however, both wild-type and phoP- bacteria were efficiently processed. The altered processing and presentation efficiency was not due to differences in the level of antigen expressed by the bacteria or differences in the level of bacterial uptake by the macrophages. In addition, phoP-regulated gene expression was shown to influence processing of antigen phagocytosed independently of the bacteria. Thus, phoP-regulated gene products decrease the processing and presentation of S. typhimurium antigens, demonstrating a role for this virulence locus in the inhibition of the induction of specific immunity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:geneSymbol
pag, phoP, phoQ, prg
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
465-76
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:7565107-Animals, pubmed-meshheading:7565107-Antigen Presentation, pubmed-meshheading:7565107-Antigens, Bacterial, pubmed-meshheading:7565107-Bacterial Proteins, pubmed-meshheading:7565107-Base Sequence, pubmed-meshheading:7565107-Epitopes, pubmed-meshheading:7565107-Gene Expression Regulation, Bacterial, pubmed-meshheading:7565107-Lysosomes, pubmed-meshheading:7565107-Macrophage Activation, pubmed-meshheading:7565107-Macrophages, pubmed-meshheading:7565107-Mice, pubmed-meshheading:7565107-Mice, Inbred BALB C, pubmed-meshheading:7565107-Mice, Inbred CBA, pubmed-meshheading:7565107-Molecular Sequence Data, pubmed-meshheading:7565107-Muramidase, pubmed-meshheading:7565107-Mutation, pubmed-meshheading:7565107-Ovalbumin, pubmed-meshheading:7565107-Recombinant Fusion Proteins, pubmed-meshheading:7565107-Salmonella typhimurium, pubmed-meshheading:7565107-Transcription Factors, pubmed-meshheading:7565107-Virulence
pubmed:year
1995
pubmed:articleTitle
The phoP locus influences processing and presentation of Salmonella typhimurium antigens by activated macrophages.
pubmed:affiliation
Immunology Unit, Lund University, Sweden.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't