Aguzzi A, Theuring F
Institute of Neuropathology, Zurich, Switzerland.
Histochemistry. 1994 Dec;102(6):477-81. doi: 10.1007/BF00269579.
The present study describes a novel method for the histochemical demonstration of beta-galactosidase activity on tissue sections. We have replaced 5-bromo-4-chloro-3-indolyl-beta-D-galactoside (X-Gal) with 5-bromo-indolyl-beta-o-galactopyranoside (Bluo-Gal) as a chromogenic substrate for the bacterial beta-galactosidase (lacZ). After beta-galactosidic cleavage, Bluo-Gal precipitates in form of fine birefringent crystals, whereas X-gal gives rise to an amorphous precipitate. Upon microscopic examination under polarized light, the crystals emit a strong signal consisting of yellow reflected light. This property of Bluo-Gal results in greatly enhanced sensitivity of the staining method for beta-galactosidase and allows for optimal morphological resolution. To exemplify the applications of this technique, the expression is demonstrated in transgenic mice of beta-galactosidase driven by a fragment of the human tissue-type plasminogen activator promoter.
本研究描述了一种在组织切片上进行β-半乳糖苷酶活性组织化学显示的新方法。我们已用5-溴吲哚基-β-D-吡喃半乳糖苷（Bluo-Gal）取代5-溴-4-氯-3-吲哚基-β-D-半乳糖苷（X-Gal）作为细菌β-半乳糖苷酶（lacZ）的显色底物。β-半乳糖苷键断裂后，Bluo-Gal以细双折射晶体的形式沉淀，而X-gal则产生无定形沉淀。在偏光显微镜下检查时，晶体发出由黄色反射光组成的强烈信号。Bluo-Gal的这一特性导致β-半乳糖苷酶染色方法的灵敏度大大提高，并实现了最佳的形态分辨率。为举例说明该技术的应用，在由人组织型纤溶酶原激活剂启动子片段驱动的β-半乳糖苷酶转基因小鼠中展示了其表达情况。
