系统性红斑狼疮患者 CD4(+) T 细胞对维 A 酸和 TGFβ 的反应缺陷。

Defective response of CD4(+) T cells to retinoic acid and TGFβ in systemic lupus erythematosus.

机构信息

Department of Medicine, Division of Rheumatology and Clinical Medicine, University of Florida, 1600 Archer Road, Gainesville, FL 32610-0275, USA.

出版信息

Arthritis Res Ther. 2011 Jun 27;13(3):R106. doi: 10.1186/ar3387.

DOI:10.1186/ar3387

PMID:21708033

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC3218921/

Abstract

INTRODUCTION

CD25(+) FOXP3(+) CD4(+) regulatory T cells (Tregs) are induced by transforming growth factor β (TGFβ) and further expanded by retinoic acid (RA). We have previously shown that this process was defective in T cells from lupus-prone mice expressing the novel isoform of the Pbx1 gene, Pbx1-d. This study tested the hypothesis that CD4(+) T cells from systemic lupus erythematosus (SLE) patients exhibited similar defects in Treg induction in response to TGFβ and RA, and that PBX1-d expression is associated with this defect.

METHODS

Peripheral blood mononuclear cells (PBMCs) were collected from 142 SLE patients and 83 healthy controls (HCs). The frequency of total, memory and naïve CD4(+) T cells was measured by flow cytometry on fresh cells. PBX1 isoform expression in purified CD4(+) T cells was determined by reverse transcription polymerase chain reaction (RT-PCR). PBMCs were stimulated for three days with anti-CD3 and anti-CD28 in the presence or absence of TGFβ and RA. The expression of CD25 and FOXP3 on CD4(+) T cells was then determined by flow cytometry. In vitro suppression assays were performed with sorted CD25(+) and CD25(-) FOXP3(+) T cells. CD4(+) T cell subsets or their expansion were compared between patients and HCs with two-tailed Mann-Whitney tests and correlations between the frequencies of two subsets were tested with Spearman tests.

RESULTS

The percentage of CD25(-) FOXP3(+) CD4(+) (CD25(-) Tregs) T cells was greater in SLE patients than in HCs, but these cells, contrary to their matched CD25(+) counterparts, did not show a suppressive activity. RA-expansion of TGFβ-induced CD25(+) Tregs was significantly lower in SLE patients than in HCs, although SLE Tregs expanded significantly more than HCs in response to either RA or TGFβ alone. Defective responses were also observed for the SLE CD25(-) Tregs and CD25(+) FOXP3(-) activated CD4(+) T cells as compared to controls. PBX1-d expression did not affect Treg induction, but it significantly reduced the expansion of CD25- Tregs and prevented the reduction of the activated CD25(+) FOXP3(-) CD4(+) T cell subset by the combination of TGFβ and RA.

CONCLUSIONS

We demonstrated that the induction of Tregs by TGFβ and RA was defective in SLE patients and that PBX1-d expression in CD4(+) T cells is associated with an impaired regulation of FOXP3 and CD25 by TGFβ and RA on these cells. These results suggest an impaired integration of the TGFβ and RA signals in SLE T cells and implicate the PBX1 gene in this process.

摘要

简介

CD25(+)FOXP3(+)CD4(+)调节性 T 细胞（Tregs）由转化生长因子 β（TGFβ）诱导，并进一步由视黄酸（RA）扩增。我们之前已经表明，在表达新型 PBX1 基因同种型的狼疮易感小鼠的 T 细胞中，该过程存在缺陷，该同种型为 PBX1-d。本研究检验了以下假设：来自系统性红斑狼疮（SLE）患者的 CD4(+)T 细胞对 TGFβ和 RA 的 Treg 诱导也表现出类似的缺陷，并且 PBX1-d 表达与该缺陷相关。

方法

从 142 例 SLE 患者和 83 例健康对照者（HCs）中收集外周血单核细胞（PBMCs）。通过流式细胞术在新鲜细胞上测量总、记忆和幼稚 CD4(+)T 细胞的频率。通过逆转录聚合酶链反应（RT-PCR）确定纯化的 CD4(+)T 细胞中 PBX1 同种型的表达。用抗 CD3 和抗 CD28 在存在或不存在 TGFβ和 RA 的情况下刺激 PBMC 3 天。然后通过流式细胞术测定 CD4(+)T 细胞上 CD25 和 FOXP3 的表达。使用分选的 CD25(+)和 CD25(-)FOXP3(+)T 细胞进行体外抑制试验。用双尾曼-惠特尼检验比较患者和 HCs 之间的 CD4(+)T 细胞亚群或其扩增，并通过斯皮尔曼检验检验两个亚群之间的频率相关性。

结果

SLE 患者中 CD25(-)FOXP3(+)CD4(+)（CD25(-)Tregs）T 细胞的百分比高于 HCs，但与匹配的 CD25(+)相比，这些细胞没有表现出抑制活性。SLE 患者中 TGFβ诱导的 CD25(+)Tregs 对 RA 的扩增明显低于 HCs，尽管 SLE Tregs 对 RA 或 TGFβ的单独反应明显高于 HCs。与对照相比，SLE CD25(-)Tregs 和 CD25(+)FOXP3(-)激活的 CD4(+)T 细胞也观察到反应缺陷。PBX1-d 表达不影响 Treg 诱导，但它显著降低了 CD25-Tregs 的扩增，并阻止了 TGFβ和 RA 组合对 CD25(+)FOXP3(-)CD4(+)T 细胞亚群的减少。

结论

我们证明了 SLE 患者中 TGFβ和 RA 诱导的 Tregs 存在缺陷，并且 CD4(+)T 细胞中的 PBX1-d 表达与 TGFβ和 RA 对这些细胞中 FOXP3 和 CD25 的调节受损有关。这些结果表明 SLE T 细胞中 TGFβ 和 RA 信号的整合受损，并暗示 PBX1 基因参与了这一过程。