Division of Life Science, Graduate School of Agriculture, Meiji University, Kanagawa, Japan.
J Neuroendocrinol. 2011 Oct;23(10):933-43. doi: 10.1111/j.1365-2826.2011.02198.x.
We reported recently that a pituitary-specific transcription factor PROP1 is present in SOX2-positive cells and disappears at the early stage of the transition from progenitor cell to committed cell during the embryonic development of the rat pituitary. In the present study, we examined the localisation and identification of SOX2-positive and PROP1/SOX2-positive cells in the neonatal and postnatal rat pituitaries by immunohistochemistry. Quantitative analysis of immunoreactive cells demonstrated that SOX2-positive pituitary stem/progenitor cells are not only predominantly localised in the marginal cell layer, but also are scattered in the parenchyma of the adult anterior lobe. In the marginal cell layer, the number of PROP1/SOX2-positive cells significantly decreased after postnatal day 15, indicating that a significant quantitative transition is triggered in the marginal cell layer during the first postnatal growth wave of the anterior pituitary. By contrast, other phenotypes of SOX2-positive stem/progenitor cells that express S100β appeared in the postnatal anterior pituitary. These data suggested that quantitative and qualitative transition occurs by acquisition of a novel mechanism in terminal differentiation in the postnatal development of the anterior pituitary.
我们最近报道称，在大鼠垂体胚胎发育过程中，一种垂体特异性转录因子 PROP1 存在于 SOX2 阳性细胞中，并在祖细胞向定向细胞分化的早期阶段消失。在本研究中，我们通过免疫组织化学技术检测了新生和新生后大鼠垂体中 SOX2 阳性和 PROP1/SOX2 阳性细胞的定位和鉴定。免疫反应细胞的定量分析表明，SOX2 阳性垂体干细胞/祖细胞不仅主要定位于边缘细胞层，而且还散在于成年前叶实质中。在边缘细胞层中，PROP1/SOX2 阳性细胞的数量在出生后第 15 天显著减少，这表明在前垂体的第一次出生后生长波期间，边缘细胞层发生了显著的数量转换。相比之下，在出生后的前垂体中出现了表达 S100β 的其他 SOX2 阳性干细胞/祖细胞表型。这些数据表明，在前垂体的出生后发育过程中，通过获得新的终末分化机制，发生了定量和定性的转换。
