Targeting pancreatic islets with phage display assisted by laser pressure catapult microdissection
Targeting pancreatic islets with phage display assisted by laser pressure catapult microdissection
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DOI：
10.1016/s0002-9440(10)62283-3
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发表时间：
2005-02-01
影响因子：
6
通讯作者：
Pasqualini, R
中科院分区：
文献类型：
--
作者：
Yao, VJ;Ozawa, MG;Pasqualini, R
不同器官中微血管的异质性已经通过多种方法包括体内噬菌体展示得到充分证明。然而，对器官功能不同区域内血管的多样性知之甚少。在这里，我们结合体内噬菌体展示与激光压力弹射显微切割，以确定肽配体的血管受体在小鼠胰腺胰岛。肽CVSNPRWKC和CHVLWSTRC的蛋白质数据库分析显示与两种肝配蛋白A型配体同源物A2和A4的序列同一性。共面显微镜证实，大多数免疫反应性的CVSNPRWKC和CHVLWSTRC噬菌体是与血管在胰岛。识别EphA 4（肝配蛋白-A配体的受体）的抗体类似地与胰岛血管相关。重要的是，胰岛归巢噬菌体和抗EphA 4抗体的结合在RIP-Tag 2转基因小鼠的胰岛肿瘤的血管中显著增加。这些结果表明，胰岛中的血管内皮细胞优先表达EphA 4受体，并且这种表达在肿瘤中增加。我们的研究结果表明，在体内噬菌体展示和激光压力弹射显微切割可以结合起来，揭示微血管的焦点区域内的内皮细胞的专业化。
Heterogeneity of the microvasculature in different organs has been well documented by multiple methods including in vivo phage display. However, less is known about the diversity of blood vessels within functionally distinct regions of organs. Here, we combined in vivo phage display with laser pressure catapult microdissection to identify peptide ligands for vascular receptors in the islets of Langerhans in the murine pancreas. Protein database analyses of the peptides, CVSNPRWKC and CHVLWSTRC, showed sequence identity to two ephrin A-type ligand homologues, A2 and A4. Confacal microscopy confirmed that most immunoreactivity of CVSNPRWKC and CHVLWSTRC phage was associated with blood vessels in pancreatic islets. Antibodies recognizing EphA4, a receptor for ephrin-A ligands, were similarly associated with islet blood vessels. Importantly, binding of both islet-homing phage and anti-EphA4 antibody was strikingly increased in blood vessels of pancreatic islet tumors in RIP-Tag2 transgenic mice. These results indicate that endothelial cells of blood vessels in pancreatic islets preferentially express EphA4 receptors, and this expression is increased in tumors. Our findings show in vivo phage display and laser pressure catapult microdissection can be combined to reveal endothelial cell specialization within focal regions of the microvasculature.