Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2005-9-8
pubmed:abstractText
In this report we provide evidence, for the first time, that bacterial DNA in the context of heat-killed Brucella abortus (HKBA) engages TLR9 in dendritic cells (DC), resulting in a Th1-like cytokine response. This is based on the findings that HKBA induction of IL-12p40 is: 1) abolished in DC from TLR9(-/-) mice; 2) blocked by suppressive oligodeoxynucleotides; 3) simulated by bacterial DNA derived from HKBA; and 4) abrogated by DNase or methylation of the DNA from HKBA. Furthermore, the effect of HKBA can be inhibited by chloroquine, indicating that endosomal acidification is required and supporting the notion that DNA from HKBA is interacting with TLR9 at the level of the endosome, as is the case with CpG oligodeoxynucleotides. In addition to DC, HKBA can elicit IL-12p40 secretion from macrophages, in which case the effect is wholly MyD88 dependent but only partially TLR9 dependent. This probably explains why HKBA effects in vivo are only partially reduced in TLR9(-/-), but absent in MyD88(-/-) mice. Because of their intimate interactions with T cells, the DC response is most likely to be critical for linking innate and adaptive immune responses, whereas the macrophage reaction may play a role in enhancing NK cell and bystander immune responses. In addition to IL-12p40, HKBA induces other Th1-like cytokines, namely, IFN-alpha and IFN-gamma, in a TLR9-dependent manner. These cytokines are important in protection against viruses and bacteria, and their induction enhances HKBA as a potential carrier for vaccines.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
175
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3964-70
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:16148144-Animals, pubmed-meshheading:16148144-Brucella abortus, pubmed-meshheading:16148144-Cytokines, pubmed-meshheading:16148144-DNA, Bacterial, pubmed-meshheading:16148144-Dendritic Cells, pubmed-meshheading:16148144-Endosomes, pubmed-meshheading:16148144-Gene Expression Regulation, pubmed-meshheading:16148144-Hot Temperature, pubmed-meshheading:16148144-Interferon-alpha, pubmed-meshheading:16148144-Interferon-gamma, pubmed-meshheading:16148144-Interleukin-12, pubmed-meshheading:16148144-Interleukin-12 Subunit p40, pubmed-meshheading:16148144-Macrophages, pubmed-meshheading:16148144-Mice, pubmed-meshheading:16148144-Mice, Knockout, pubmed-meshheading:16148144-Protein Subunits, pubmed-meshheading:16148144-Th1 Cells, pubmed-meshheading:16148144-Toll-Like Receptor 9, pubmed-meshheading:16148144-Vaccines, Inactivated
pubmed:year
2005
pubmed:articleTitle
Th1-like cytokine induction by heat-killed Brucella abortus is dependent on triggering of TLR9.
pubmed:affiliation
Division of Hematology, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892, USA.
pubmed:publicationType
Journal Article