Dumont N, O'Connor-McCourt M D, Philip A
Department of Animal Science, McGill University, Montreal, Canada.
Mol Cell Endocrinol. 1995 Apr 28;111(1):57-66. doi: 10.1016/0303-7207(95)03548-l.
In the present study, we have characterized the cell surface receptors for transforming growth factor-beta (TGF-beta) on monolayer cultures of stromal cells prepared from human endometrial biopsies, and on a human endometrial epithelial cell line (RL95-2) using affinity cross-link labeling techniques. On the stromal cells, five TGF-beta binding proteins were identified. Analysis of the sensitivity of these proteins to dithiothreitol and phosphatidylinositol-specific phospholipase C, together with results from immunoprecipitations with antibodies against the type II and III TGF-beta receptors, confirmed that three of these binding proteins correspond to the cloned type I, II, and III TGF-beta receptors. The other two binding proteins observed exhibit the characteristics of isoform-specific GPI-anchored TGF-beta binding proteins. On RL95-2 cells, three TGF-beta binding proteins, corresponding to the type I, II, and III TGF-beta receptors, were identified. The receptors which we have characterized on endometrial cells are responsive to physiological concentrations of TGF-beta as demonstrated by the effect of TGF-beta on endometrial cell proliferation. Accordingly, these receptors have the potential to respond to the TGF-beta isoforms which have recently been detected in the endometrium in an autocrine and/or paracrine manner.
在本研究中，我们利用亲和交联标记技术，对取自人子宫内膜活检组织的基质细胞单层培养物以及人子宫内膜上皮细胞系（RL95 - 2）上的转化生长因子-β（TGF-β）细胞表面受体进行了特性鉴定。在基质细胞上，鉴定出了五种TGF-β结合蛋白。通过分析这些蛋白对二硫苏糖醇和磷脂酰肌醇特异性磷脂酶C的敏感性，以及用抗II型和III型TGF-β受体抗体进行免疫沉淀的结果，证实其中三种结合蛋白对应于克隆的I型、II型和III型TGF-β受体。观察到的另外两种结合蛋白表现出同种型特异性糖基磷脂酰肌醇（GPI）锚定的TGF-β结合蛋白的特征。在RL95 - 2细胞上，鉴定出了三种对应于I型、II型和III型TGF-β受体的TGF-β结合蛋白。我们在子宫内膜细胞上鉴定出的受体对生理浓度的TGF-β有反应，这通过TGF-β对子宫内膜细胞增殖的影响得以证明。因此，这些受体有可能以自分泌和/或旁分泌方式对最近在子宫内膜中检测到的TGF-β同种型作出反应。
