Dysfunction of hepatic regulatory T cells in experimental sclerosing cholangitis is associated with IL-12 signaling. Mus musculus

In this study we successfully enriched regulatory T cells (Treg) in the liver using injections with IL-2/IL-2ab complex. Enriched Treg were mainly located in areas of inflammation, but they had no impact on liver inflammation or fibrosis in two different cholangitis mouse models. We found that liver derived Treg had less suppressive capacity compared to splenic derived Treg. We used microarray analysis of IL-2/IL-2ab complex enriched liver and splenic derived regulatory T cells in order to elucidate the organ specific differences. We identified upregulation of IL12 receptor beta 2 on hepatic Treg and could identify IL-12 signalling as key factor for reduced suppressive capacity of regulatory T cells. Overall design: Regulatory T cells were expanded by repeated injection of IL-2/IL-2Ab complex in vivo. Enriched Treg were isolated from spleen and liver for RNA extraction and hybridization on Affymetrix microarrays.

本研究通过注射IL-2/IL-2ab复合物，成功在小鼠肝脏中富集了调节性T细胞（regulatory T cells，Treg）。富集得到的调节性T细胞主要分布于炎症区域，但在两种不同的胆管炎小鼠模型中，此类细胞并未对肝脏炎症或纤维化产生影响。本研究发现，肝脏来源的调节性T细胞其抑制功能弱于脾脏来源的调节性T细胞。为阐明器官特异性差异，本研究对经IL-2/IL-2ab复合物富集的肝脏及脾脏来源调节性T细胞进行了微阵列分析。本研究鉴定出肝脏调节性T细胞上IL12受体β2（IL12 receptor beta 2）表达上调，并确定IL-12信号通路是导致调节性T细胞抑制功能减弱的关键因素。实验整体设计：通过体内反复注射IL-2/IL-2ab复合物扩增调节性T细胞，随后从脾脏和肝脏中分离富集得到的调节性T细胞，用于RNA提取及Affymetrix微阵列杂交。