Linked Life Data

12594841

Source:http://linkedlifedata.com/resource/pubmed/id/12594841

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-2-20
pubmed:abstractText
There is convincing evidence that soluble HLA-A,-B,-C (sHLA-A,-B,-C) and soluble HLA-G (sHLA-G) antigens can induce apoptosis in CD8(+) activated T cells although there is scanty and conflicting information about the mechanism(s) by which sHLA-A,-B,-C antigens and sHLA-G antigens induce apoptosis. In this study we have compared the apoptosis-inducing ability of sHLA-A,-B,-C antigens with that of sHLA-G1 antigens in CD8(+) T lymphocytes and CD8(+) NK cells. Furthermore we have compared the inhibitory effect of sHLA-A,-B,-C antigens and of sHLA-G1 antigens on the activity of EBV-specific CD8(+) cytotoxic T lymphocytes (CTL). sHLA molecules were purified from serum and from the supernatant of HLA class I-negative cells transfected with one gene encoding either classical or non-classical HLA class I antigens. Both classical and non-classical sHLA class I molecules trigger apoptosis in CD8(+) T lymphocytes and in CD8(+) NK cells, which lack the T cell receptor, and their apoptotic potency is comparable. The binding of sHLA-A,-B,-C and sHLA-G1 molecules to CD8 leads to Fas ligand (FasL) up-regulation, soluble FasL (sFasL) secretion and CD8(+) cell apoptosis by Fas/sFasL interaction. Moreover, classical and non-classical sHLA class I molecules inhibit the cytotoxic activity of EBV-specific CD8(+) CTL. As the amount ofsHLA-G molecules detectable in normal serum is significantly lower than that of sHLA-A,-B,-C molecules, the immunomodulatory effects of sHLA class I molecules purified from serum are likely to be mainly attributable to classical HLA class I antigens. As far as the potential in vivo relevance of these findings is concerned, we suggest that classical sHLA class I molecules may play a major immunoregulatory role in clinical situations characterized by activation of the immune system and elevated sHLA-A,-B,-C serum levels. In contrast, non-classical HLA class I molecules may exert immunomodulatory effects in particular conditions characterized by elevated sHLA-G levels such as pregnancy and some neoplastic diseases.
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
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
125-34
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Soluble HLA-A,-B,-C and -G molecules induce apoptosis in T and NK CD8+ cells and inhibit cytotoxic T cell activity through CD8 ligation.
pubmed:affiliation
Department of Internal Medicine (DIMI), University of Genova, Genova, Italy.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't