Linked Life Data

21690238

Source:http://linkedlifedata.com/resource/pubmed/id/21690238

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2011-8-17
pubmed:abstractText
Group B streptococcus (GBS) is a common commensal of the gastrointestinal and vaginal mucosa and a leading cause of serious infections in newborns, the elderly, and immunocompromised populations. GBS also causes infections of the urinary tract. However, little is known about host responses to GBS urinary tract infection (UTI) or GBS virulence factors that participate in UTI. Here we describe a novel murine model of GBS UTI that may explain some features of GBS urinary tract association in the human host. We observed high titers and heightened histological signs of inflammation and leukocyte recruitment in the GBS-infected kidney. However, extensive inflammation and leukocyte recruitment were not observed in the bladder, suggesting that GBS may suppress bladder inflammation during cystitis. Acute GBS infection induced the localized expression of proinflammatory cytokines interleukin-1? (IL-1?), macrophage inflammatory protein-1? (MIP-1?), MIP-1?, and IL-9, as well as IL-10, more commonly considered an anti-inflammatory cytokine. Using isogenic GBS strains with different capsule structures, we show that capsular sialic acid residues contribute to GBS urinary tract pathogenesis, while high levels of sialic acid O-acetylation attenuate GBS pathogenesis in the setting of UTI, particularly in direct competition experiments. In vitro studies demonstrated that GBS sialic acids participate in the suppression of murine polymorphonuclear leukocyte (PMN) bactericidal activities, in addition to reducing levels of IL-1?, tumor necrosis factor alpha, IL-1?, MIP-1?, and KC produced by PMNs. These studies define several basic molecular and cellular events characterizing GBS UTI in an animal model, showing that GBS participates simultaneously in the activation and suppression of host immune responses in the urinary tract.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1098-5522
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3588-95
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Immune activation and suppression by group B streptococcus in a murine model of urinary tract infection.
pubmed:affiliation
Department of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, MO 63110, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural