Erickson G F, Hofeditz C, Unger M, Allen W R, Dulbecco R
Endocrinology. 1985 Oct;117(4):1490-9. doi: 10.1210/endo-117-4-1490.
When screening supernatant fluids from hybridoma clones, Dulbecco and co-workers found that a mouse monoclonal antibody generated against a mammary tumor cell line showed rather striking high binding to rat oocytes and granulosa cells. In this study we have specifically investigated the reactivity of the monoclonal antibody (designated anti-OA-1) with granulosa cells during the differentiation process. This was accomplished using the two-step indirect immunocytochemical technique. When a primordial follicle is recruited to initiate growth, intense immunoreactivity appears in the surface membrane of the granulosa cells. As a follicle proceeds through the preantral stages, the plasma membrane of the granulosa cells is strongly positive for anti-OA-1 reactivity, and the granulosa appear as a homogeneous population. However, once Graafian follicle development is initiated, a major shift in anti-OA-1 immunoreactivity occurs among the granulosa cells. As the antrum expands, 75% of the granulosa in the mural region (those nearest the basal lamina) elongate and become negative for anti-OA-1. This is in contrast to the periantral and cumulus granulosa, which remain rounded and show strong anti-OA-1 reactivity up to the preovulatory stage. The disappearance of anti-OA-1 reactivity in the subpopulation of mural cells is specifically initiated by FSH and occurs very rapidly after a 12-h lag phase. After the loss of anti-OA-1 reactivity, the elongated mural granulosa cells express their terminal differentiated state by acquiring LH/hCG receptor, 3 beta-hydroxysteroid dehydrogenase activity and cytoplasmic lipid inclusions. By contrast, the periantral and cumulus granulosa, which remain positive for anti-OA-1, do not express these differentiated functions; however, they do differentiate ultrastructurally, indicating that they respond to the FSH signal. These results strongly suggest that a monoclonal antibody recognizes a major surface differentiation antigen in the granulosa cell. This antigen is under hormonal control and is inversely linked to expression of the terminal differentiation program in the granulosa cells. We anticipate that the monoclonal antibody will be a valuable probe to aide in the analysis of structure/function relationships in subpopulations of granulosa cells.
在筛选杂交瘤克隆的上清液时，达尔伯克及其同事发现，一种针对乳腺肿瘤细胞系产生的小鼠单克隆抗体与大鼠卵母细胞和颗粒细胞表现出相当显著的高结合力。在本研究中，我们专门研究了单克隆抗体（命名为抗 - OA - 1）在分化过程中与颗粒细胞的反应性。这是通过两步间接免疫细胞化学技术完成的。当原始卵泡被募集开始生长时，颗粒细胞表面膜出现强烈的免疫反应性。随着卵泡进入窦前阶段，颗粒细胞的质膜对抗 - OA - 1反应呈强阳性，且颗粒细胞呈现为均一群体。然而，一旦始基卵泡发育开始，颗粒细胞中抗 - OA - 1免疫反应性就会发生重大变化。随着卵泡腔扩大，壁层区域（最靠近基膜的那些）75%的颗粒细胞伸长并对抗 - OA - 1呈阴性。这与卵泡周围和卵丘颗粒细胞形成对比，它们在排卵前阶段一直保持圆形并显示出强烈的抗 - OA - 1反应性。壁层细胞亚群中抗 - OA - 1反应性的消失是由促卵泡激素（FSH）特异性启动的，并且在12小时的延迟期后非常迅速地发生。在失去抗 - OA - 1反应性后，伸长的壁层颗粒细胞通过获得促黄体生成素/人绒毛膜促性腺激素（LH/hCG）受体、3β - 羟基类固醇脱氢酶活性和细胞质脂质包涵体来表达其终末分化状态。相比之下，对抗 - OA - 1仍呈阳性的卵泡周围和卵丘颗粒细胞不表达这些分化功能；然而，它们在超微结构上确实发生了分化，表明它们对FSH信号有反应。这些结果强烈表明，一种单克隆抗体识别颗粒细胞中的一种主要表面分化抗原。这种抗原受激素控制，并且与颗粒细胞终末分化程序的表达呈负相关。我们预计这种单克隆抗体将成为一种有价值的探针，有助于分析颗粒细胞亚群中的结构/功能关系。
