Treutelaar Mary Kay, Skidmore Jennifer M, Dias-Leme Claudia L, Hara Manami, Zhang Lizhi, Simeone Diane, Martin Donna M, Burant Charles F
Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA.
Diabetes. 2003 Oct;52(10):2503-12. doi: 10.2337/diabetes.52.10.2503.
To clarify the lineage relationship between cells that express the neural stem cell marker nestin and endocrine cells of the pancreas, we analyzed offspring of a cross between mice carrying a nestin promoter/enhancer-driven cre-recombinase (Nestin-cre) and C57BL/6J-Gtrosa26(tm1Sor) mice that carry a loxP-disrupted beta-galactosidase gene (Rosa26). In nestin-cre(+/tg);R26R(loxP/+) embryos, cre-recombinase was detected in association with nestin-positive cells in the pancreatic mesenchyme with some of the nestin-positive cells lining vascular channels. In postnatal mice, pancreatic beta-galactosidase expression was restricted to vascular endothelial cells of the islet and a subset of cells in the muscularis of arteries in a distribution identical to endogenous nestin expression. Ex vivo explants of mouse pancreatic ducts grew dense cultures that costained for nestin and beta-galactosidase, demonstrating recombination in vitro. The cultures could be differentiated into complex stereotypic structures that contain nestin- and insulin-expressing cells. Nestin-cre(+/tg);R26R(loxP/+)-derived duct cultures showed that insulin-positive cells were negative for beta-galactosidase. These results indicate that both in vivo and in vitro pancreatic endocrine cells arise independently of nestin-positive precursors. The apparent vascular nature of the nestin-positive cell population and the close association with endocrine cells suggest that nestin-positive cells play an important role in the growth and maintenance of the islet.
为了阐明表达神经干细胞标志物巢蛋白的细胞与胰腺内分泌细胞之间的谱系关系，我们分析了携带巢蛋白启动子/增强子驱动的cre重组酶（Nestin-cre）的小鼠与携带loxP破坏的β-半乳糖苷酶基因（Rosa26）的C57BL/6J-Gtrosa26(tm1Sor)小鼠杂交后代。在nestin-cre(+/tg);R26R(loxP/+)胚胎中，在胰腺间充质中与巢蛋白阳性细胞相关联地检测到cre重组酶，一些巢蛋白阳性细胞排列在血管通道内衬。在出生后的小鼠中，胰腺β-半乳糖苷酶表达仅限于胰岛的血管内皮细胞和动脉肌层中的一部分细胞，其分布与内源性巢蛋白表达相同。小鼠胰管的体外外植体培养出密集的培养物，这些培养物对巢蛋白和β-半乳糖苷酶进行了共染色，证明了体外重组。这些培养物可以分化为包含表达巢蛋白和胰岛素的细胞的复杂定型结构。来自nestin-cre(+/tg);R26R(loxP/+)的导管培养物显示胰岛素阳性细胞对β-半乳糖苷酶呈阴性。这些结果表明，无论是在体内还是体外，胰腺内分泌细胞均独立于巢蛋白阳性前体产生。巢蛋白阳性细胞群体的明显血管性质以及与内分泌细胞的密切关联表明，巢蛋白阳性细胞在胰岛的生长和维持中起重要作用。
