Qualmann B, Kessels M M, Klobasa F, Jungblut P W, Sierralta W D
Max-Planck-Institut für experimentelle Endokrinologie, Hannover, Germany.
J Microsc. 1996 Jul;183(Pt 1):69-77. doi: 10.1046/j.1365-2818.1996.71435.x.
Two small homogeneous markers for electron spectroscopic imaging (ESI) containing eight dodecaborane cages linked to a poly-alpha, epsilon-L-lysine dendrimer were synthesized; one of these was made water soluble by the attachment of a polyether. The markers were coupled to the sulfhydryl group of (monovalent) antibody fragments (Fab') by a homobifunctional cross-linker. While the coupling ratios of the poorly water-soluble compound did not exceed 20%, the polyether-containing variant reacted quantitatively. Its suitability for immunolabelling was tested in a study of the mechanism of the transcellular transport of an administered heterologous protein (bovine serum albumin, BSA) through ileal enterocytes of newborn piglets by endocytotic vesicles in comparison to conventional immunogold reagents. The post-embedding technique was employed. The boronated Fab' gave rise to considerably higher tagging frequencies than seen with immunogold, as could be expected from its form- and size-related physical advantages and the dense packing of BSA in the vesicles. The new probe, carrying the antigen-combining cleft at one end and the boron clusters at the opposite end of the oval-shaped conjugate, add to the potential of ESI-based immunocytochemistry.
合成了两种用于电子光谱成像（ESI）的小型均相标记物，它们包含八个与聚α,ε-L-赖氨酸树枝状聚合物相连的十二硼烷笼；其中一种通过连接聚醚使其具有水溶性。这些标记物通过同双功能交联剂与（单价）抗体片段（Fab'）的巯基偶联。虽然水溶性较差的化合物的偶联率不超过20%，但含聚醚的变体反应完全。与传统免疫金试剂相比，在一项关于经内吞小泡给予的异源蛋白（牛血清白蛋白，BSA）通过新生仔猪回肠肠细胞进行跨细胞转运机制的研究中，测试了其免疫标记的适用性。采用了包埋后技术。如从其与形状和大小相关的物理优势以及小泡中BSA的密集堆积所预期的那样，硼化的Fab'产生的标记频率比免疫金高得多。这种新探针在椭圆形缀合物的一端带有抗原结合裂隙，在另一端带有硼簇，增加了基于ESI的免疫细胞化学的潜力。
