Linked Life Data

21742974

Source:http://linkedlifedata.com/resource/pubmed/id/21742974

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2011-8-3
pubmed:abstractText
Dendritic cells (DCs) can initiate immune responses or confer immune tolerance depending on functional status. LPS-induced DC maturation is defined by enhanced surface expression of CD80 and CD86. MicroRNAs are critical for the regulation of DC function and immunity, and the microRNA let-7i was upregulated during LPS-induced DC maturation. Downregulation of let-7i significantly impeded DC maturation as evidenced by reduced CD80 and CD86 expression. DCs stimulated by LPS promoted T cell proliferation in coculture, whereas LPS-stimulated DCs with downregulated let-7i were not effective at stimulating T cell proliferation but promoted expansion of the regulatory T cell (Treg) population. There were two subpopulations of LPS-stimulated DCs with downregulated let-7i, CD86(-) and CD86(+), and it was the CD86(-) DCs that were more effective in inducing T cell hyporesponsiveness and enhancing Treg numbers, indicating that this DC population had tolerogenic properties. Furthermore, Tregs with upregulated IL-10 underscored the tolerogenic effect of CD86(-) DCs. Suppressor of cytokine signaling 1 (SOCS1), a crucial mediator of DC maturation, was confirmed as a let-7i target gene by luciferase construct assay. Suppression or overexpression of let-7i caused reciprocal alterations in SOCS1 protein expression, but had no significant effects on SOCS1 mRNA levels, indicating that let-7i regulated SOCS1 expression by translational suppression. The modulation of SOCS1 protein by let-7i was mainly restricted to CD86(-) DCs. Our study demonstrates that let-7i regulation of SOCS1 is critical for LPS-induced DC maturation and immune function. Dynamic regulation of let-7i may fine-tune immune responses by inducing Ag-specific immune tolerance.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1550-6606
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
187
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1674-83
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Inhibition of microRNA let-7i depresses maturation and functional state of dendritic cells in response to lipopolysaccharide stimulation via targeting suppressor of cytokine signaling 1.
pubmed:affiliation
Key Laboratories of Education Ministry for Myocardial Ischemia Mechanism and Treatment, Harbin Medical University, Harbin, Heilongjiang Province 150081, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't