Ferreira A, Nussenzweig V, Gigli I
J Exp Med. 1978 Nov 1;148(5):1186-97. doi: 10.1084/jem.148.5.1186.
Based on functional and structural data, it is concluded that the Ss protein in the mouse expresses the activity of the fourth component of complement. Removal of the Ss, but not of Slp, antigen correlates with a high degree of significance (P less than 0.001) with decrease of C4 hemolytic activity. In phenotypically Slp negative mice the plasma/serum levels of Ss correlate with the C4 activity (P less than 0.001). Structurally, Ss is a 209,000-mol wt protein, consisting of three covalently linked polypeptide chains (alpha,beta,gamma). Treatment of Ss with C1 cleaves a 7,000-8,000-mol wt fragment from the alpha-chain. Slp is also a three chain covalently linked protein of 209,000 daltons, however its three chains differ in size from those of the Ss protein. Slp does not express hemolytic activity and its alpha-chain is not cleaved by C1.
基于功能和结构数据,得出结论:小鼠中的Ss蛋白表达补体第四成分的活性。去除Ss抗原而非Slp抗原与C4溶血活性的降低具有高度显著性相关(P小于0.001)。在表型上为Slp阴性的小鼠中,Ss的血浆/血清水平与C4活性相关(P小于0.001)。在结构上,Ss是一种分子量为209,000的蛋白质,由三条共价连接的多肽链(α、β、γ)组成。用C1处理Ss会从α链上切割下一个分子量为7,000 - 8,000的片段。Slp也是一种分子量为209,000道尔顿的三聚体共价连接蛋白,但其三条链的大小与Ss蛋白的不同。Slp不表达溶血活性,其α链也不会被C1切割。