Polymorphism of murine Fas ligand that affects the biological activity
Polymorphism of murine Fas ligand that affects the biological activity
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DOI：
10.1073/pnas.94.8.3914
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发表时间：
1997-04-15
影响因子：
11.1
通讯作者：
Yagita, H
中科院分区：
文献类型：
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作者：
Kayagaki, N;Yamaguchi, N;Yagita, H
Fas 配体 (FasL) 是肿瘤坏死因子家族的成员，可诱导带有 Fas (CD95) 的靶细胞凋亡。在本研究中，我们生成了几种与小鼠 Fast (mFasL) 反应的 mAB，并表征了它们的功能特性。其中一种 mAb K10 与源自 C57BL/6 (B6) 小鼠的 mFasL 发生特异性反应，但根据表面染色和阻断 mFasL 转染子的细胞毒性活性估计，与来自 BALB/c 小鼠的 mFasL 不发生反应，表明 mFasL 存在多态性。对多个品系的 mFasL cDNA 进行序列分析表明，BALB/c 和 DBA/2 小鼠与已知的 B6 和 C3H 序列存在 3 个核苷酸差异，导致胞外区出现两个氨基酸取代（Thr-184 --> Ala-184 和 Glu-218 --> Gly-218）。通过 PCR 限制性片段长度多态性对 K10 反应性和基因分型进行的分析表明，近交小鼠分为以下两种同种异型：mFasL.1（B6、C3H、MRL、SJL、NOD、NZB、NZW）和 mFasL.2（BALB/c、DBA/1、DBA/2）。有趣的是，表达 BALB/c FasL 的 COS7 细胞比表达 B6 FasL 的细胞更有效地裂解带有 Fas 的靶细胞。此外，BALB/c 衍生的 CD8-FasL 融合蛋白由人 CD8 α 和 mFasL 的胞外结构域组成，其比活性比 B6 衍生的 CD8-FasL 高 9 倍。这些结果表明，在 mFasL.2 小鼠中，Fas/FasL 系统比在 mFasL.1 小鼠中更有效地工作。
Fas ligand (FasL) is a member of the tumor necrosis factor family and induces apoptosis in Fas (CD95)-bearing target cells. In this study, we generated several mABs that react with mouse Fast (mFasL) and characterized their functional properties. One of these mAbs, K10, specifically reacted with mFasL derived from C57BL/6 (B6) mice, but not that from BALB/c mice as estimated by surface staining and blocking of cytotoxic activities of mFasL transfectants, suggesting a polymorphism of mFasL. Sequence analysis of mFasL cDNA from several strains revealed that BALB/c and DBA/2 mice have three nucleotide differences from the known B6 and C3H sequences, which result in two amino acid substitutions (Thr-184 --> Ala-184 and Glu-218 --> Gly-218) in the extracellular region. Analysis of the K10 reactivity and genotyping by PCR-restriction fragment length polymorphism revealed that inbred mice segregate into the following two allotypes: mFasL.1 (B6, C3H, MRL, SJL, NOD, NZB, NZW) and mFasL.2 (BALB/c, DBA/1, DBA/2). Interestingly, COS7 cells expressing BALB/c FasL lysed Fas-bearing target cells more efficiently than those expressing B6 FasL. Furthermore, BALB/c-derived CD8-FasL fusion protein, which is composed of the extracellular domains of human CD8 alpha and mFasL, exhibited 9-fold higher specific activity than did B6-derived CD8-FasL. These results suggest that in mFasL.2 mice the Fas/FasL system works more effectively than in mFasL.1 mice.