α2-巨球蛋白是一种源自星形胶质细胞的神经突促进因子，作用于来自大鼠中枢神经系统的培养神经元。

Alpha 2-macroglobulin is an astroglia-derived neurite-promoting factor for cultured neurons from rat central nervous system.

作者信息

Mori T, Iijima N, Kitabatake K, Kohsaka S

机构信息

Biochemistry Section, Asahi Breweries, Ltd., Tokyo, Japan.

出版信息

Brain Res. 1990 Sep 10;527(1):55-61. doi: 10.1016/0006-8993(90)91059-p.

DOI:10.1016/0006-8993(90)91059-p

PMID:1704280

Abstract

The neurite promoting factors in the astroglial conditioned medium (As-CM) were characterized by using primary cultures of embryonic rat neocortical neurons. The factors in the As-CM bind to lectins such as wheat germ agglutinin (WGA), suggesting that they contain sugar moieties. When the WGA-bound fractions were applied on a Superose 6 column, the activity was recovered mainly in two fractions, peak I and peak II. The peak II fraction was further purified by Mono Q anion exchange chromatography. A single protein band of 180 kDa was detected in the final Mono Q fraction by sodium dodecylsulfate polyacrylamide gel electrophoresis. The molecular weight coincided with that of alpha 2-macroglobulin (alpha 2M). Western blotting showed that the single protein band was reacted with anti-alpha 2M antibody but not with anti-fibronectin and anti-laminin antisera. The neurite-promoting activity of the Mono Q fraction was inhibited by anti-alpha 2M antibody. Furthermore, commercially available alpha 2M also promotes neurite outgrowth in our assay system. These results strongly suggested that alpha 2M is one of the neurite-promoting factors in the As-CM.

摘要

利用胚胎大鼠新皮质神经元的原代培养物对星形胶质细胞条件培养基（As-CM）中的神经突促进因子进行了表征。As-CM中的因子可与诸如麦胚凝集素（WGA）等凝集素结合，这表明它们含有糖基部分。当将与WGA结合的部分应用于Superose 6柱时，活性主要在两个部分中恢复，即峰I和峰II。峰II部分通过Mono Q阴离子交换色谱进一步纯化。通过十二烷基硫酸钠聚丙烯酰胺凝胶电泳在最终的Mono Q部分中检测到一条180 kDa的单一蛋白带。其分子量与α2-巨球蛋白（α2M）的分子量一致。蛋白质免疫印迹显示，该单一蛋白带与抗α2M抗体反应，但不与抗纤连蛋白和抗层粘连蛋白抗血清反应。Mono Q部分的神经突促进活性被抗α2M抗体抑制。此外，市售的α2M在我们的测定系统中也能促进神经突生长。这些结果有力地表明，α2M是As-CM中的神经突促进因子之一。