Expression of the interleukin-2 receptor on human fibroblasts and its biological significance.
Expression of the interleukin-2 receptor on human fibroblasts and its biological significance.
复制标题
白细胞介素2受体在人成纤维细胞上的表达及其生物学意义。
作者：
S. Plaisance;E. Rubinstein;Abdelkrim Allleche;Y. Sahraoui;P. Krief;Y. Augery;Claude Jasmine;Horacio Suarez;B. Azzarone
在这项研究中，我们研究了IL-2受体（IL-2R α和IL-2R β）的α链和β链在人胚胎成纤维细胞寿命期间在膜和转录水平上的表达。本研究表明，针对IL-2R α和IL-2R β的IL-2结合位点的单克隆抗体IOT14和MIK β 1分别在人类胚胎成纤维细胞生命早期染色。来自[125I]rIL2交联实验的数据显示，两种IL-2结合肽分别在胚胎幼期成纤维细胞和淋巴样活化细胞上同时表达70和55 kDa。p55和p70 IL-2结合肽对IL-2R α和IL-2R β具有特异性，发现这些带被过量的冷IL-2和针对α链和β链的IL-2结合位点的单克隆抗体所消除。[125I]IL-2标记后的Scatchard分析显示存在高亲和力（150个位点，Kd为147 pM）和低亲和力（1100个位点，Kd为4 nM） IL-2结合位点。Northern blot和dot blot分析显示，在早期传代成纤维细胞中存在IL-2R α和IL-2R β基因的特异性转录本。相比之下，在衰老培养中，仅检测到IL-2R β转录本。最后，IL-2在低浓度（36 pM）下下调了年轻细胞间粘附分子ICAM-1的水平，而在老年培养中则没有。（摘要删节250字）
In this study, we have investigated the expression of the alpha and beta chains of the IL-2 receptor (IL-2R alpha, IL-2R beta) both at the membrane and at transcriptional levels during the lifespan of human embryonic fibroblasts. Here we show that the mAbs IOT14 and MIK beta 1 directed against the IL-2 binding sites of the IL-2R alpha and IL-2R beta respectively, stain human embryonic fibroblasts early in their life span. Data from [125I]rIL2 cross-linking experiments show the simultaneous expression of two IL-2 binding peptides of 70 and 55 kDa respectively on embryonic young fibroblasts as on lymphoid activated cells. The p55 and the p70 IL-2 binding peptides are shown to be specific for the IL-2R alpha and to the IL-2R beta by the finding that these bands are abolished by excess amounts of cold IL-2 and mAbs directed against the IL-2 binding sites of the alpha and beta chains. Scatchard analysis after [125I]IL-2 labelling shows the presence of both high affinity (150 sites with a Kd of 147 pM) and low affinity (1100 sites with a Kd of 4 nM) IL-2 binding sites. Northern blot and dot blot analysis show the presence of specific transcripts for the IL-2R alpha and IL-2R beta genes in early passaged fibroblasts. By contrast, in senescent cultures, only the IL-2R beta transcript were detected. Finally, IL-2 at low concentrations (36 pM) down modulates the level of the intercellular adhesion molecule ICAM-1 in young but not in senescent cultures.(ABSTRACT TRUNCATED AT 250 WORDS)