Spontaneous release of the Leu-2 (T8) molecule from human T cells.
Spontaneous release of the Leu-2 (T8) molecule from human T cells.
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DOI：
10.1084/jem.158.3.752
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发表时间：
1983-09-01
期刊：
影响因子：
--
通讯作者：
Levy R
中科院分区：
文献类型：
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作者：
Fujimoto J;Levy S;Levy R
已经开发了用于检测可溶形式的人T细胞抗原的灵敏的酶联免疫吸附测定（ELISA）。该检测使用小鼠单克隆抗体和特异性抗Leu血清，通过用吸附在单克隆抗体亲和柱上的Leu抗原免疫家兔制备。使用这些测定，可以检测到来自少至5 X 10（3）个细胞的提取物的Leu-1、Leu-2和Leu-3抗原信号。当测试来自各种细胞系的培养物上清液时，发现存在Leu-2抗原，但不存在Leu-1或Leu-3。Leu-2抗原仅存在于在其细胞表面上表达Leu-2的T细胞系的上清液中。Leu-2抗原在低密度培养上清中逐渐积累，其存在不依赖于细胞增殖或培养基中的胎牛血清。Leu-2抗原在上清液中被发现只有一个Leu-2a决定簇，而Leu-2抗原从细胞提取物中至少有两个决定簇。用抗Leu-2a亲和柱从上清液中有效纯化Leu-2分子。从HPB-ALL细胞的上清液中纯化的Leu-2抗原是27，000 mol wt的单一多肽链，而存在于HPB-ALL细胞表面上的Leu-2抗原由通过二硫键连接的33，000 mol wt的两条或更多条相同的多肽链组成。还检查了正常人血清和白血病患者血清中Leu-2抗原的存在。正常人血清含有低水平的Leu-2抗原，但来自Leu-2阳性白血病患者的血清具有高水平。这些结果表明Leu-2抗原在生理条件下从人T细胞释放。
Sensitive enzyme-linked immunosorbent assays (ELISA) for the detection of human T cell antigens in soluble form have been developed. The assays use mouse monoclonal antibodies and specific anti-Leu sera prepared in rabbits by immunizing with Leu antigens absorbed to monoclonal antibody affinity columns. With these assays, Leu-1, -2, and -3 antigen signals from extracts of as few as 5 X 10(3) cells could be detected. When culture supernatants from various cell lines were tested, Leu-2 antigen, but not Leu-1 or Leu-3, was found to be present. Leu-2 antigen was present only in supernatants from T cell lines that expressed Leu-2 on their cell surface. Leu-2 antigen accumulated progressively in the supernatant of low density culture and its presence did not depend on cell proliferation or on fetal calf serum in the culture medium. The Leu-2 antigen in the supernatant was found to have only one Leu-2a determinant, whereas Leu-2 antigen from cell extracts had at least two determinants. The Leu-2 molecule was effectively purified from supernatant with an anti-Leu-2a affinity column. The purified Leu-2 antigen from supernatant of HPB-ALL cells was a single polypeptide chain of 27,000 mol wt, whereas Leu-2 antigen present on HPB-ALL cell surface was composed of two or more identical polypeptide chains of 33,000 mol wt linked by disulfide bonds. Normal human sera and sera from leukemia patients were also examined for the presence of the Leu-2 antigen. Normal human sera contained low levels of Leu-2 antigen but sera from Leu-2-positive leukemia patients had high levels. These results indicate that Leu-2 antigen is released from human T cells under physiological conditions.