Lipsett Mark A, Castellarin Mauro L, Rosenberg Lawrence
Research Institute of the McGill University Health Centre and the Department of Surgery, McGill University, Montreal, Quebec, Canada.
Pancreas. 2007 May;34(4):452-7. doi: 10.1097/MPA.0b013e3180335c80.
The plasticity of pancreatic tissue is demonstrated in many pancreatic diseases. It has previously been shown that pancreatic islet-to-duct transformation and acinoductal metaplasia have been associated with both pancreatic regeneration and adenocarcinoma in various in vivo and in vitro settings. Understanding this inherent morphogenetic plasticity of the adult pancreas could lead to new therapeutic approaches to pancreatic disease.
Cadaveric human pancreases (n = 7) were digested, and purified acinar tissue, which was approximately 85% immunoreactive for amylase and approximately 15% immunoreactive for CK-19, was embedded in a type 1 collagen matrix and cultured in a differentiation medium (DM) consisting of Dulbecco modified Eagle/F12 medium supplemented with cholera toxin (100 ng/mL), epidermal growth factor (10 ng/mL), and insulin (24 mU/mL) for 8 days. After this initial period, the resulting tissues were cultured in DM without cholera toxin, supplemented with gastrin (50 nmol/L) and hepatocyte growth factor (HGF; 10 ng/mL), with islet neogenesis-associated protein (INGAP; 167 nmol/L) or with gastrin + HGF + INGAP for 6 days. Tissue samples were then analyzed for amylase, cytokeratin 19, pancreas duodenum homeobox 1, and endocrine hormone immunoreactivity as well as dithizione positivity.
After 8 days of culture, approximately 90% of acini transformed into ductlike structures. This acinoductal transformation was characterized by a complete absence of amylase staining, with virtually all cells CK-19 immunoreactive. Addition of INGAP led to an approximately 18-fold increase in pancreas duodenum homeobox 1 immunoreactivity, although without an observed increase in insulin production as measured by dithizone positivity. However, when acinar-derived ductlike structures were cultured with gastrin + HGF + INGAP, the total incidence of dithizone-positive structures increased approximately 6-fold (10.9 +/- 2.9% vs 1.7 +/- 0.4%, P = 0.037). Treatment with gastrin + HGF alone led to no significant change in any of the measured parameters.
We have developed a novel in vitro model of adult human acinoductal metaplasia that will aid not only in developing new methods of expanding beta-cell mass but also provide insights into pancreatic carcinogenesis.
胰腺组织的可塑性在许多胰腺疾病中都有体现。此前已有研究表明，在各种体内和体外环境中，胰岛向导管的转变以及腺泡导管化生与胰腺再生和腺癌均有关联。了解成年胰腺这种固有的形态发生可塑性可能会带来治疗胰腺疾病的新方法。
对7例尸体供体的人类胰腺进行消化处理，将纯化后的腺泡组织（淀粉酶免疫反应性约为85%，细胞角蛋白19免疫反应性约为15%）包埋于Ⅰ型胶原基质中，并在由杜氏改良伊格尔培养基/F12培养基补充霍乱毒素（100 ng/mL）、表皮生长因子（10 ng/mL）和胰岛素（24 mU/mL）组成的分化培养基（DM）中培养8天。在此初始阶段之后，将所得组织在不含霍乱毒素的DM中培养6天，该培养基补充了胃泌素（50 nmol/L）、肝细胞生长因子（HGF；10 ng/mL）、胰岛新生相关蛋白（INGAP；167 nmol/L）或胃泌素+HGF+INGAP。然后对组织样本进行淀粉酶、细胞角蛋白19、胰腺十二指肠同源盒1、内分泌激素免疫反应性以及双硫腙阳性检测分析。
培养8天后，约90%的腺泡转变为导管样结构。这种腺泡导管化生的特征是淀粉酶染色完全缺失，几乎所有细胞均呈细胞角蛋白19免疫反应阳性。添加INGAP导致胰腺十二指肠同源盒1免疫反应性增加约18倍，不过通过双硫腙阳性检测未观察到胰岛素生成增加。然而，当腺泡来源的导管样结构与胃泌素+HGF+INGAP一起培养时，双硫腙阳性结构的总发生率增加了约6倍（10.9±2.9%对1.7±0.4%，P = 0.037）。单独用胃泌素+HGF处理在任何测量参数上均未导致显著变化。
我们建立了一种新型的成年人类腺泡导管化生体外模型，这不仅有助于开发扩大β细胞量的新方法，还能为胰腺癌发生机制提供见解。
