The integrin alpha4beta7 forms a complex with cell-surface CD4 and defines a T-cell subset that is highly susceptible to infection by HIV-1.
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ABSTRACT:
SUBMITTER: Cicala C
PROVIDER: S-EPMC2780317 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:A common method used both in vitro and in vivo, to identify Tregs in CD4+ T cells is through the characterization of surface marker CD25. Although CD25 expression is well correlated with regulatory activity in vitro, CD4+CD25+ T cells are not the only regulatory CD4+ T cells in vivo. Studies suggest that in many situations, CD4+CD25– T cells are as effective as CD4+CD25+ T cells in controlling T cell mediated disease. Therefore, CD25 is not a uniquely specific cell surface marker for the identification of Tregs. CD49f is an α6-integrin subunit which dimerizes with either the β 1 or β 4 subunit to form receptors for various laminin isoforms. We found that CD4+ T cells from NOD mice express CD49f, and old non-diabetic NOD mice had an increase of CD4+CD49f+ T cells in the spleen and peripheral lymph node when compared to both young and diabetic mice. This study was conducted to further characterize CD4+CD49f+ Treg cell subpopulation in NOD mice. It was found that CD4+CD49f+T cells possess suppressive ability and only one third of CD4+CD49f+ T cells expressing CD25. Based on the expression of CD49f and CD25, CD4+ T cells was divided into four populations , CD25+CD49f+ ,CD25+CD49f- ,CD25-CD49f+ but CD25-CD49f- are of suppressive ability, and we further found that Foxp3 expression was highly correlated with the suppressive ability of these three Treg populations. In conclusion our data indicate that CD49f marks a CD4+ CD25+ Treg subset with more potent suppression activity and identifies a CD25-CD4+ T cell population with suppression function in a Foxp3+ expression dependent manner.
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