α_2M是血液中一种具有重要生物学活性的大分子糖蛋白,由四个结构与分子量均相同的亚单位组成,由淋巴细胞、单核细胞及成纤维母细胞合成和释放。在体外实验中α_2M能改变网状细胞对各种刺激的反应,并在白细胞与红细胞生成过程中起作用。近年来研究发现,α_2M是血浆中一种重要的蛋白酶抑制因子,可抑制四种内肽酶活性。α_2M α 2 M is a macromolecule glycoprotein with important biological activity in the blood. It consists of four subunits of the same structure and molecular weight and is synthesized and released by lymphocytes, monocytes and fibroblasts. In vitro experiments, α 2 M can change the response of reticular cells to various stimuli and play a role in leukocyte and erythropoiesis processes. In recent years, it has been found that α_2M is an important protease inhibitor in plasma and inhibits the activity of four endopeptidases. α_2M