Linked Life Data

11970982

Source:http://linkedlifedata.com/resource/pubmed/id/11970982

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2002-4-23
pubmed:abstractText
Normal T cell repertoire contains regulatory T cells that control autoimmune responses in the periphery. One recent study demonstrated that CD4(+)CD25(+) T cells were generated from autoreactive T cells without negative selection. However, it is unclear whether, in general, positive selection and negative selection of autoreactive T cells are mutually exclusive processes in the thymus. To investigate the ontogeny of CD4(+)CD25(+) regulatory T cells, neo-autoantigen-bearing transgenic mice expressing chicken egg OVA systemically in the nuclei (Ld-nOVA) were crossed with transgenic mice expressing an OVA-specific TCR (DO11.10). Ld-nOVA x DO11.10 mice had increased numbers of CD4(+)CD25(+) regulatory T cells in the thymus and the periphery despite clonal deletion. In Ld-nOVA x DO11.10 mice, T cells expressing endogenous TCR alpha beta chains were CD4(+)CD25(-) T cells, whereas T cells expressing autoreactive TCR were selected as CD4(+)CD25(+) T cells, which were exclusively dominant in recombination-activating gene 2-deficient Ld-nOVA x DO11.10 mice. In contrast, in DO11.10 mice, CD4(+)CD25(+) T cells expressed endogenous TCR alpha beta chains, which disappeared in recombination-activating gene 2-deficient DO11.10 mice. These results indicate that part of autoreactive T cells that have a high affinity TCR enough to cause clonal deletion could be positively selected as CD4(+)CD25(+) T cells in the thymus. Furthermore, it is suggested that endogenous TCR gene rearrangement might critically contribute to the generation of CD4(+)CD25(+) T cells from nonautoreactive T cell repertoire, at least under the limited conditions such as TCR-transgenic models, as well as the generation of CD4(+)CD25(-) T cells from autoreactive T cell repertoire.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
168
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4399-405
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Generation of CD4(+)CD25(+) regulatory T cells from autoreactive T cells simultaneously with their negative selection in the thymus and from nonautoreactive T cells by endogenous TCR expression.
pubmed:affiliation
Department of Allergy and Rheumatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't