Development of pancreatic stem cell and β-cell for cell therapy

Maf是一个转录因子蛋白家族，Maf a是细胞系中胰岛素的强反激活因子。我们前期在大鼠胰腺急性缺血条件下诱导mmas的大量表达，提示mmas可能不仅参与细胞功能的调节，还参与胰腺的发育和分化。本研究研究了maf家族在猪胰腺和原代培养细胞中的表达谱。与成人胰腺组织相比，新生儿胰腺组织中胰岛的形成尚不清楚。Maf A和c阳性细胞在胰腺组织中弥散分布，染色强烈，在中央腺泡区周围较少Maf B阳性聚集细胞。相比之下，胰岛的形成更为明显，maf A和c的阳性染色在成人胰腺组织的胰岛中更为突出。在内分泌功能方面，maf A与胰高血糖素分泌细胞有更多的胰岛素和c-maf。实时荧光定量PCR检测的mmas mRNA水平在胰腺组织中全面表达。从新生胰腺组织中分离的内分泌细胞原代培养物中也检测到mmas mRNA的表达。每个maf可能是调节表达的，是内分泌功能的特异性和独立的反激活因子。Maf B也可能具有结构形成或激素分泌的其他潜能。胎儿和成人胰腺组织与猪相似，maf染色呈阳性，提示猪胰腺可能是人类胰腺的一个原型。初生c-maf基因敲除小鼠胰腺体积较小，但已形成。综上所述，在胰腺和培养的内分泌细胞中发现了大maffs，其表达水平和定位在新生儿和成人胰腺组织中存在差异。maff可能在胰腺内分泌细胞分化过程中以独立和特异性的方式参与内分泌功能的建立。少

Maf is a family of transcription factor proteins, and maf A is a strong transactivator of insulin in cell lines. The induction of large mafs expression in rat pancreas under acute ischemic conditions in our previous study suggests that mafs may be involved not only in the regulation of cell function, but also in the development and differentiation of the pancreas. The present study investigated the expression profiles of the large maf family in the porcine pancreas and in primary culture cells. In the newborn pancreas tissue, the formation of islets was not clear compared with that in the adult pancreas tissue. Maf A- and c-positive cells were more diffuse and intensely stained in the pancreas tissue scatted throughout with fewer maf B positive clustering cells around at centroacinar area. In contrast, islet formation was more apparent and positive staining for maf A and c tended to be prominent in the islets of the adult pancreas tissue, As to endocrine function, maf A corresponds to … More insulin-and c-maf to glucagon-secreting cells, based on the results of a double staining study. Mafs mRNA levels measured by real-time PCR were overall expressed in the pancreas tissue. Mafs mRNA expression was also detectable in the primary cultures of endocrine cells freshly isolated from the newborn pancreas tissue. Each maf may be regulatory expressed and specific and independent transactivator of endocrine function. Maf B may also have other potentials for structure formation or hormone secretion. Fetal and adult human pancreas tissues stained positive for maf similarly as porcine, suggesting that porcine pancreas can be one prototype of human pancreas. Preliminarily, pancreas was small size but formed in newborn of c-maf knockout mice. In conclusion, large mafs were identified in pancreas and cultured endocrine cells, and the expression level and localization differ in newborn and adlut pancreas tissue. Mafs may play roles in establishing endocrine function during pancreatic endocrine cell differentiation in independent and specific manner. Less