Alpha-2-macroglobulin-protease complex (A2M-protease complex (A2M))

Alpha-2-macroglobulin is a large plasma glycoprotein and **broad-spectrum protease inhibitor** that modulates cytokines and growth factors by sequestering active proteases within a tetrameric “cage” following cleavage of its bait region[1][5][7]. This *Venus flytrap* or *snap-trap* mechanism allows A2M to physically and sometimes covalently trap a diversity of proteases, preventing them from degrading important extracellular proteins and regulating activities such as cytokine signaling, tissue remodeling, inflammation, and defense against pathogens[1][2][5][7]. The A2M–protease complex is subsequently recognized and cleared via receptor-mediated endocytosis by target cells[5]. Disruption in A2M function or levels has been linked to diseases involving inflammation, proteostasis imbalance, cancer progression, and infection[1][3][7]. Experimentally, this complex is also used as a platform for protease engineering and identification[4]. The alpha-2-macroglobulin-protease complex is thus a valid and characterized target, particularly in the context of **cytokine modulation via complex formation**[1][7].

Other names

Alpha-2-macroglobulinalpha 2-macroglobulinA2Mα2-macroglobulin

Drugs or molecules targeting A2M typically work by enhancing or mimicking its protease-trapping ability, either for anti-protease therapy or selectively clearing specific molecules (experimental; mechanism not broadly exploited by approved drugs)