Pacholczyk Rafal, Kern Joanna, Singh Nagendra, Iwashima Makio, Kraj Piotr, Ignatowicz Leszek
Center for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta, GA 30912, USA.
Immunity. 2007 Sep;27(3):493-504. doi: 10.1016/j.immuni.2007.07.019.
The majority of regulatory Foxp3+CD4+ T cells naturally arises in the thymus. It has been proposed that T cell receptors (TCRs) on these cells recognize self-MHC class II-peptide complexes with high or higher affinity and that their specificities mirror specificities of autoreactive T cells. Here, we analyzed hundreds of TCRs derived from regulatory or nonregulatory T cells and found little evidence that the former population preferably recognizes self-antigens as agonists. Instead, these cells recognized foreign MHC-peptide complexes as often as nonregulatory T cells. Our results show that high-affinity, autoreactive TCRs are rare on all CD4+ T cells and suggest that selecting self-peptide is different from the peptide that activates the same regulatory T cells in the periphery.
大多数具有调节功能的Foxp3+CD4+ T细胞自然产生于胸腺。有人提出，这些细胞上的T细胞受体（TCR）以高亲和力或更高亲和力识别自身MHC II类肽复合物，并且它们的特异性反映了自身反应性T细胞的特异性。在这里，我们分析了数百个源自调节性或非调节性T细胞的TCR，几乎没有证据表明前者群体更倾向于将自身抗原识别为激动剂。相反，这些细胞识别外来MHC-肽复合物的频率与非调节性T细胞相同。我们的结果表明，高亲和力的自身反应性TCR在所有CD4+ T细胞上都很罕见，这表明选择的自身肽与在外周激活相同调节性T细胞的肽不同。
