Linked Life Data

9498743

Source:http://linkedlifedata.com/resource/pubmed/id/9498743

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1998-3-18
pubmed:abstractText
Ag recognition is an essential component for an effective T cell response. However, T cell activation is also subject to additional regulation by accessory molecules. CD28 provides essential costimulatory signals that allow T cells to proliferate, whereas molecules such as CTLA-4 and CD95 (Fas) appear to be negative regulators. Currently, which outcome predominates under conditions of antigenic challenge is poorly understood. In particular it has been suggested that one consequence of antigenic activation of T cells is the up-regulation of both CD95 and CD95 ligand, thereby exposing activated T cells to apoptotic death. We have investigated this possibility in normal human peripheral blood T cells triggered by the superantigen SEB either in the presence of endogenous APCs or transfectants expressing DR4 and CD80. In either case, we find that such activation does not expose the majority of T cells to anti-CD95-induced apoptosis as detected by annexin V externalization and DNA fragmentation. Furthermore, by phenotypically identifying, by flow cytometry, those cells that received both antigenic and costimulatory signals from those cells that did not, we observed that CD95-induced apoptosis was not seen in activated T cells receiving Ag and costimulatory signals via CD28. However, while not all T cells were stimulated by superantigen, CD95 expression was found to be homogeneously up-regulated, suggesting a mechanism whereby bystander cells might be made susceptible to CD95-induced death. We conclude that antigenic activation of T cells via the TCR and CD28 engagement provides protection from CD95-induced apoptosis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
160
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2072-9
pubmed:dateRevised
2010-8-25
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Activation of human T cells with superantigen (staphylococcal enterotoxin B) and CD28 confers resistance to apoptosis via CD95.
pubmed:affiliation
Bath Institute for Rheumatic Diseases, Department of Pharmacy and Pharmacology, University of Bath, United Kingdom.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't