Linked Life Data

7678231

Source:http://linkedlifedata.com/resource/pubmed/id/7678231

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1993-2-8
pubmed:abstractText
We have recently shown that activation of T cells causes structural changes in the interleukin-7 receptor (IL-7R) (Foxwell et al. Int. Immunol. 1992, 4: 277). Unactivated cells expressed a receptor characterized as a cross-linked protein of 107-kDa whereas activated cells had reduced levels of this 107-kDa complex and now express a major cross-linked product of 93 kDa. These changes in receptor expression were concomitant with the acquisition of IL-7 growth responsiveness by activated T cells. In this study, the effect of the potent immunosuppressive agents cyclosporin A and FK506 on the activation-induced responsiveness to IL-7-driven proliferation and the concomitant changes in receptor structure have been investigated. Cyclosporin A and FK506 suppressed the expression of the 93-kDa complex and the loss of the 107-kDa complex on activated cells. The presence of exogenous IL-7 inhibited the effects of the drugs on IL-7R structure, allowing expression of the 93-kDa complex. Expression of the 93-kDa complex could also be induced either by ionomycin or phorbol esters. As observed for other T cell activation parameters, only those which induced a calcium signal (ionomycin) but not protein kinase C (phorbol esters) were sensitive to the drugs. In all studies, the expression of the 93-kDa complex correlated with the ability of cells to proliferate to IL-7, and thus these results further support the hypothesis that the 93-kDa form of the IL-7R is required to transmit the cytokine's growth signal. Moreover, these data suggest that activation-induced transcriptional events are required for the expression of the 93-kDa complex and the down-regulation of the 107-kDa complex. As reported for IL-2R and IL-4R, our data also show that the expression of another T cell growth factor receptor is sensitive to the effects of cyclosporin A and FK506. These observations also have important implications for reported cyclosporin A effects on the thymus where IL-7 can act as a growth factor for thymocytes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0014-2980
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
85-9
pubmed:dateRevised
2009-9-29
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Inhibition of activation-induced changes in the structure of the T cell interleukin-7 receptor by cyclosporin A and FK506.
pubmed:affiliation
Kennedy Institute for Rheumatology-Sunley Division, Hammersmith, London, GB.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't