Owen M J, Auger J, Barber B H, Edwards A J, Walsh F S, Crumpton M J
Proc Natl Acad Sci U S A. 1978 Sep;75(9):4484-8. doi: 10.1073/pnas.75.9.4484.
Lymphocytes were assessed for the presence of surface actin and myosin by lactoperoxidase-catalyzed iodination and indirect immunofluorescence using antisera against purified pig skeletal muscle actin and pig smooth muscle myosin. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis of 125I-labeled pig, mouse, and human B lymphocytes revealed an intense radioactive band of 43,000 molecular weight, whereas pig and mouse T lymphocytes gave a much less intense band. This band comigrated with actin, was nonglycosylated as judged by lack of binding to lentil lectin-Sepharose, was bound specifically by myosin fibers, and could be distinguished from a polypeptide of similar mobility derived from the major histocompatibility antigens. These results suggest that actin is present on the surface of B lymphocytes and, to a lesser extent, on T lymphocytes. Pig, mouse, and human Ig-bearing cells were stained by antiactin and antimyosin antisera, as judged by indirect immunofluorescence, whereas non-Ig-bearing cells were not stained. Antibody binding, however, was depleted by adsorbing the antisera with Ig-Sepharose. It was concluded that the immunofluorescence results are misleading and reflect the presence of antibodies that crossreact with Ig.
通过使用抗纯化猪骨骼肌肌动蛋白和猪平滑肌肌球蛋白的抗血清，经乳过氧化物酶催化碘化和间接免疫荧光法评估淋巴细胞表面肌动蛋白和肌球蛋白的存在情况。对125I标记的猪、小鼠和人B淋巴细胞进行十二烷基硫酸钠/聚丙烯酰胺凝胶电泳，显示出一条分子量为43,000的强放射性条带，而猪和小鼠T淋巴细胞的条带强度则低得多。这条带与肌动蛋白共迁移，根据其不与扁豆凝集素-琼脂糖结合判断为非糖基化，能被肌球蛋白纤维特异性结合，且可与主要组织相容性抗原衍生的具有相似迁移率的多肽区分开来。这些结果表明肌动蛋白存在于B淋巴细胞表面，在T淋巴细胞表面的含量较少。经间接免疫荧光判断，猪、小鼠和人携带Ig的细胞被抗肌动蛋白和抗肌球蛋白抗血清染色，而不携带Ig的细胞未被染色。然而，用Ig-琼脂糖吸附抗血清后，抗体结合被耗尽。得出的结论是，免疫荧光结果具有误导性，反映了与Ig发生交叉反应的抗体的存在。
