SIALOADHESIN, A MACROPHAGE SIALIC-ACID BINDING-RECEPTOR FOR HEMATOPOIETIC-CELLS WITH 17 IMMUNOGLOBULIN-LIKE DOMAINS
SIALOADHESIN, A MACROPHAGE SIALIC-ACID BINDING-RECEPTOR FOR HEMATOPOIETIC-CELLS WITH 17 IMMUNOGLOBULIN-LIKE DOMAINS
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DOI：
10.1002/j.1460-2075.1994.tb06771.x
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发表时间：
1994-10-03
期刊：
影响因子：
11.4
通讯作者：
BRADFIELD, P
中科院分区：
文献类型：
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作者：
CROCKER, PR;MUCKLOW, S;BRADFIELD, P
唾液粘附素是一种185 kDa的巨噬细胞限制性黏附分子，介导唾液酸依赖的细胞结合。它在淋巴和造血组织中的巨噬细胞强烈表达，在这些组织中它可能介导细胞与细胞之间的相互作用。本文报道了小鼠唾液酸粘附素的分子克隆，发现它是免疫球蛋白(Ig)超家族的一个新成员，具有17个Ig样结构域。转染全长唾液酸粘附素的COS细胞以唾液酸依赖的方式与小鼠骨髓细胞结合。或者，预测唾液粘附素的可溶性形式的剪接的cDNA，包含唾液粘附素的前3个或16个Ig样结构域，在COS细胞中表达并纯化相应的蛋白。当固定在塑料上时，16个结构域以唾液酸依赖的方式形成结合细胞，这表明唾液粘附素可以以分泌和膜结合的形式发挥作用。数据库中最相似的蛋白质是CD22、髓鞘相关糖蛋白、雪旺细胞髓鞘蛋白和CD33。与唾液酸粘附素一样，CD22介导唾液酸依赖的细胞黏附。唾液酸粘附素与CD22和Ig超家族相关成员的序列相似性表明，存在一个参与细胞-细胞相互作用的新的唾液酸结合蛋白家族。
Sialoadhesin is a macrophage-restricted adhesion molecule of 185 kDa that mediates sialic acid-dependent binding to cells. It is expressed strongly by macrophages in lymphoid and haemopoietic tissues where it is likely to mediate cell-cell interactions. Here we report the molecular cloning of murine sialoadhesin and show that it is a new member of the immunoglobulin (Ig) superfamily with 17 Ig-like domains. COS cells transfected with a cDNA encoding full-length sialoadhesin bound mouse bone marrow cells in a sialic acid-dependent manner. Alternatively spliced cDNAs, predicting soluble forms of sialoadhesin containing the first three or 16 Ig-like domains of sialoadhesin, were expressed in COS cells and the respective proteins purified. When immobilized on plastic, the 16-domain form bound cells in a sialic acid-dependent manner, suggesting that sialoadhesin can function in both secreted and membrane-bound forms. The most similar proteins in the database were CD22, myelin-associated glycoprotein, Schwann cell myelin protein and CD33. Like sialoadhesin, CD22 mediates sialic acid-dependent cell adhesion. The sequence similarity of sialoadhesin to CD22 and related members of the Ig superfamily indicates the existence of a novel family of sialic acid binding proteins involved in cell-cell interactions.