Somosy Z, Kubasova T, Ecsedi G S, Köteles G J
Int J Radiat Biol Relat Stud Phys Chem Med. 1986 Jun;49(6):969-78. doi: 10.1080/09553008514553191.
By binding cationized ferritin (CF) to the plasma membrane of primary human fibroblasts, the amount and topology of negatively charged sites on cell surfaces were studied after X-irradiation. The CF binding was tested both on fixed and unfixed cells. Using various enzymes, the chemical nature of sites carrying the negative charges on cell surfaces was investigated. The results suggest that in unirradiated fibroblasts the CF binding occurred in a polarized manner, i.e. the particles were localized mainly on the apical surface of cells and formed clusters. The thin cytoplasmic protrusions and cell-to-cell contact sites bound CF to a greater extent than the bleb-like formations. Enzymatic digestion of surface polysaccharides showed that the main carriers of negatively charged sites are the glycosaminoglycans associated with the cell surface. The fixation of cells with glutaraldehyde did not influence the topology of CF binding either before or after the enzymatic treatment. After X-irradiation with 2.5 Gy the topology of CF binding did not change but the CF coverage of cells as well as the amount of ferritin particles per unit of surface area decreased within 10 min. The changes proved to be reversible as the values reached the pre-irradiation level by 1 h after irradiation.
通过将阳离子铁蛋白（CF）结合到原代人成纤维细胞的质膜上，研究了X射线照射后细胞表面带负电荷位点的数量和拓扑结构。在固定和未固定的细胞上都测试了CF结合情况。使用各种酶，研究了细胞表面携带负电荷位点的化学性质。结果表明，在未照射的成纤维细胞中，CF以极化方式结合，即颗粒主要定位在细胞的顶端表面并形成簇。薄的细胞质突起和细胞间接触位点比泡状结构结合CF的程度更大。表面多糖的酶消化表明，带负电荷位点的主要载体是与细胞表面相关的糖胺聚糖。用戊二醛固定细胞在酶处理前后均不影响CF结合的拓扑结构。用2.5 Gy的X射线照射后，CF结合的拓扑结构没有改变，但细胞的CF覆盖以及每单位表面积的铁蛋白颗粒数量在10分钟内减少。结果证明这些变化是可逆的，因为照射后1小时这些值达到了照射前的水平。
