Thiel E, Dörmer P, Ruppelt W, Thierfelder S
J Immunol Methods. 1976;12(3-4):237-51. doi: 10.1016/0022-1759(76)90045-4.
A quantitative autoradiographic method is presented for determining absolute amounts of 125I-labeled compounds on the surface of individual cells. Autoradiographic evaluation of single cell radioactivity is accomplished by comparing the silver grain densities over the specimen and a radioactive standard being exposed simultaneously. In order to obtain a reference source of comparable physical properties, surface-radioiodinated human erythrocytes are used, the radioactivity of which is determined in a crystal counter. A simple enzymatic method for preparing such standard erythrocytes of very uniform label density is described. Numerous experimental advantages derived from the use of the standard are discussed and demonstrated by examples employing various exposure times and different radioactive standards. Hereby, very similar results were obtained when the number of A-antigenic sites was quantified on single erythrocytes in different experiments. The quantification of membrane-bound IgM on single human lymphocytes is shown as another application of this scheme.
本文介绍了一种定量放射自显影方法，用于测定单个细胞表面125I标记化合物的绝对量。通过比较标本上的银粒密度与同时曝光的放射性标准物来完成单细胞放射性的放射自显影评估。为了获得具有可比物理性质的参考源，使用表面放射性碘化的人红细胞，其放射性在晶体计数器中测定。描述了一种制备具有非常均匀标记密度的此类标准红细胞的简单酶法。讨论并通过采用不同曝光时间和不同放射性标准的示例证明了使用该标准所带来的诸多实验优势。由此，在不同实验中对单个红细胞上A抗原位点的数量进行定量时，获得了非常相似的结果。该方案的另一个应用是显示单个人淋巴细胞上膜结合IgM的定量。
