Immunoglobulin of T lymphoma cells. Biosynthesis, surface representation, and partial characterization.
Immunoglobulin of T lymphoma cells. Biosynthesis, surface representation, and partial characterization.
复制标题
T 淋巴瘤细胞的免疫球蛋白。
DOI：
10.1021/bi00680a004
复制
发表时间：
1975
期刊：
影响因子：
2.9
通讯作者：
A. W. Harris
中科院分区：
文献类型：
--
作者：
D. Haustein;J. Marchalonis;A. W. Harris
研究了4株连续培养的小鼠T淋巴瘤细胞系WEHI-22.1、WEHI-7.1、S49.1和EL-4.1的免疫球蛋白生物合成及细胞表面免疫球蛋白的存在。将[-3H]亮氨酸掺入细胞蛋白后进行血清学分析表明，免疫球蛋白占不同细胞系在6小时内合成蛋白的0.1%至1.1%。在相同条件下培养的非淋巴细胞源性肥大细胞瘤P-815 X-2.1不合成任何可检测到的免疫球蛋白。乳酸过氧化物酶催化放射性碘化用于标记活的淋巴瘤和肥大细胞瘤细胞表面的蛋白质。虽然通过荧光抗体染色评估淋巴瘤系缺乏免疫球蛋白，但在所有四种淋巴瘤系的表面蛋白中均检测到免疫球蛋白。细胞表面免疫球蛋白分子数S49.1和EL-4.1为1.1倍10-4/细胞，WEHI-7.1为1.7倍10-4/细胞，WEHI-22.1为4.3倍10-4/细胞。十二烷基硫酸钠聚丙烯酰胺凝胶中的电泳迁移率表明，完整细胞表面的免疫球蛋白略大于IgG，并通过二硫键还原解离成两种组分，一种具有血清免疫球蛋白轻链的迁移率，另一种具有类似于mu重链的迁移率。来自T淋巴瘤细胞的重链的表观分子量约为65,000，而mu链的表观分子量为70,000，尽管这两条链都具有mu链特征的抗原决定因素。这些发现被解释为支持T淋巴细胞表面携带免疫球蛋白的其他报道，并作为胸腺源性淋巴样细胞合成类似于IgM的7S亚基的免疫球蛋白的直接证据。
Four cloned continuously cultured mouse T lymphoma cell lines, WEHI-22.1, WEHI-7.1, S49.1, and EL-4.1, were examined for immunoglobulin biosynthesis and the presence of immunoglobulin on the cell surface. Incorporation of [-3H]leucine into cellular proteins followed by serological analysis showed that immunoglobulin constituted between 0.1 and 1.1 percent of protein synthesized by the different cell lines during a 6-hr period. Under the same conditions cultured cells of nonlymphoid origin, the mastocytoma P-815 X-2.1, did not synthesize any detectable immunoglobulin. Lactoperoxidase-catalyzed radioiodination was used to label proteins on the surface of viable lymphoma and mastocytoma cells. Although the lymphoma lines lacked immunoglobulin as assessed by fluorescent antibody staining, immunoglobulin was detected in surface proteins of all four lymphoma lines. Estimates of the number of immunoglobulin molecules on the cell surface were 1.1 times 10-4/cell for S49.1 and EL-4.1, 1.7 times 10-4 for WEHI-7.1, and 4.3 times 10-4 for WEHI-22.1. Electrophoretic mobilities in sodium dodecyl sulfate polyacrylamide gel indicated that intact cell surface immunoglobulin was slightly larger than IgG, and on disulfide bond reduction to dissociate into two components, one with the mobility of serum immunoglobulin light chain, the other with a mobility similar to that of mu heavy chain. The heavy chain from the T lymphoma cells possessed an apparent molecular weight of about 65,000 compared with 70,000 for mu chain, although both chains shared antigenic determinants characteristic of mu chains. These findings are interpreted as support for other reports that T lymphocytes carry immunoglobulin on their surface and as direct evidence that thymus-derived lymphoid cells synthesize an immunoglobulin resembling the 7S subunit of IgM.