Lebovic D I, Chao V A, Martini J F, Taylor R N
Reproductive Endocrinology Division, Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI 48109-0276, USA.
J Clin Endocrinol Metab. 2001 Oct;86(10):4759-64. doi: 10.1210/jcem.86.10.7890.
A complex network of cytokines mediates immunoregulatory responses in the pathogenesis of endometriosis. RANTES (regulated upon activation, normal T cell expressed and secreted) is a chemoattractant for monocytes and T cells. Endometriotic lesions express RANTES, and its concentration in peritoneal fluid correlates with the severity of endometriosis. We investigated the influence of IL-1beta, a potent macrophage cytokine, on RANTES production in endometriotic stromal cells and determined the region of the RANTES promoter responsible for IL-1beta action. RANTES mRNA was induced 5-fold in endometriotic stromal cells, and the conditioned medium RANTES protein concentrations were 12-fold higher in IL-1beta-treated endometriotic stromal cells vs. untreated controls (P < 0.05). IL-1beta activated the full-length (-940 bp) RANTES promoter as well as a truncated 456-bp 5'-flanking construct by 2-fold. Mutagenesis of a nuclear factor-kappaB response element at -30 bp abolished the IL-1beta effect, whereas mutation of a nearby TNF response element did not affect the IL-1beta induction. An IL-1beta time-course Western assay revealed a rapid diminution of IkappaB (endogenous inhibitor of nuclear factor-kappaB) in endometriotic stromal cells. Overexpression of IkappaB in endometriotic stromal cells inhibited the IL-1beta response of the RANTES gene promoter. Transcription of RANTES mRNA is up-regulated by IL-1beta via a nuclear factor-kappaB response element in the proximal RANTES gene promoter. These results demonstrate a feed-forward regulatory loop in the pathogenesis of endometriosis by which IL-1beta produced from activated macrophages can lead to further macrophage recruitment via RANTES production in endometriotic stromal cells.
细胞因子的复杂网络在内异症发病机制中介导免疫调节反应。RANTES（活化时表达和分泌的调节正常T细胞表达和分泌因子）是单核细胞和T细胞的趋化因子。内异症病灶表达RANTES，其在腹水中的浓度与内异症的严重程度相关。我们研究了强效巨噬细胞细胞因子IL-1β对内异症基质细胞中RANTES产生的影响，并确定了RANTES启动子中负责IL-1β作用的区域。内异症基质细胞中RANTES mRNA诱导增加了5倍，与未处理的对照相比，IL-1β处理的内异症基质细胞的条件培养基RANTES蛋白浓度高12倍（P<0.05）。IL-1β使全长（-940 bp）RANTES启动子以及截短的456 bp 5'侧翼构建体活化了2倍。-30 bp处的核因子-κB反应元件诱变消除了IL-1β的作用，而附近肿瘤坏死因子反应元件的诱变不影响IL-1β诱导。IL-1β时间进程的蛋白质免疫印迹分析显示内异症基质细胞中IkappaB（核因子-κB的内源性抑制剂）迅速减少。内异症基质细胞中IkappaB的过表达抑制了RANTES基因启动子的IL-1β反应。RANTES mRNA的转录通过RANTES基因启动子近端的核因子-κB反应元件被IL-1β上调。这些结果证明了内异症发病机制中的前馈调节环，通过该调节环，活化巨噬细胞产生的IL-1β可通过内异症基质细胞中RANTES的产生导致进一步的巨噬细胞募集。
