Combined analysis of immunostaining for various biological molecules coupled with investigations of ultrastructural features of individual cells is a powerful approach for studies of cellular functions in normal and pathological conditions. However, weak antigenicity of tissues fixed by conventional methods poses a problem for immunoassays. This study introduces a method of correlative light and electron microscopy imaging of the same endocrine cells of compact and diffuse islets from human pancreatic tissue specimens. The method utilizes serial sections obtained from Epon-embedded specimens fixed with glutaraldehyde and osmium tetroxide. Double-immunofluorescence staining of thick Epon sections for endocrine hormones (insulin and glucagon) and regenerating islet-derived gene 1 α (REG1α) was performed following the removal of Epoxy resin with sodium ethoxide, antigen retrieval by autoclaving, and de-osmification treatment with hydrogen peroxide. The immunofluorescence images of endocrine cells were superimposed with the electron microscopy images of the same cells obtained from serial ultrathin sections. Immunofluorescence images showed well-preserved secretory granules in endocrine cells, whereas electron microscopy observations demonstrated corresponding secretory granules and intracellular organelles in the same cells. In conclusion, the correlative imaging approach developed by us may be useful for examining ultrastructural features in combination with immunolocalisation of endocrine hormones in the same human pancreatic islets.

中文翻译：

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改进的连续切片技术，用于相关的人类朗格汉斯胰岛光电子显微镜成像。

对各种生物分子进行免疫染色的联合分析以及对单个细胞超微结构特征的研究，是研究正常和病理条件下细胞功能的有力方法。然而，通过常规方法固定的组织的弱抗原性给免疫测定带来了问题。这项研究介绍了一种相关的光和电子显微镜成像方法，可以对人胰腺组织标本中的紧密和弥散性胰岛的相同内分泌细胞进行成像。该方法利用从戊二醛和四氧化固定的Epon嵌入式标本中获得的连续切片。在用乙醇钠去除环氧树脂，高压灭菌后进行抗原回收并通过脱脂处理后，对内分泌激素（胰岛素和胰高血糖素）的厚Epon区和再生的胰岛衍生基因1α（REG1α）进行了双免疫荧光染色。过氧化氢。内分泌细胞的免疫荧光图像与从连续超薄切片获得的相同细胞的电子显微镜图像重叠。免疫荧光图像显示内分泌细胞中保存完好的分泌颗粒，而电子显微镜观察显示相同细胞中相应的分泌颗粒和细胞内细胞器。综上所述，