These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Characterization of human CD25+ CD4+ T cells in thymus, cord and adult blood.
    Author: Wing K, Ekmark A, Karlsson H, Rudin A, Suri-Payer E.
    Journal: Immunology; 2002 Jun; 106(2):190-9. PubMed ID: 12047748.
    Abstract:
    CD4(+) CD25(+) regulatory T cells prevent organ-specific autoimmune diseases in various animal models. We analysed human lymphoid tissues to identify similar CD25(+) regulatory T cells. Adult peripheral blood contained two populations of CD4(+) T cells that expressed CD25 at different densities. The larger population (approximately 40%) expressed intermediate levels of CD25 (CD25(+)) and displayed a memory T-cell phenotype (CD45RA-/RO(+), CD45RB(low), CD95(+), CD62L(low), CD38(low)). The smaller population of cells (approximately 2%) expressed very high levels of CD25 (CD25(++)). In addition to the activation/memory T-cell antigens mentioned above they also expressed intracellular CD152 (CTLA-4) as well as enhanced levels of cell-surface CD122, similar to the murine CD4(+) CD25(+) regulatory counterpart. To exclude that the CD25(++) cells had not been recently primed by external antigen we analysed cord blood and thymus. CD25(++), CD152(+) and CD122(++) cells were present in paediatric thymus (10% of CD4(+) CD8(-) thymocytes) expressing signs of recent selection (CD69+) and in cord blood (5% of CD4(+) cells) where they showed a naive phenotype. In addition, cord blood contained a small population of CD25(+) cells (approximately 2% of CD4 T cells) that were CD152(-) and CD122(low) and displayed signs of activation. Together with published data that CD25(+) CD25(++) cells from the thymus and peripheral blood are regulatory, our results suggest that regulatory CD25(+) T cells leave the thymus in a naïve state and become activated in the periphery.
    [Abstract] [Full Text] [Related] [New Search]