Serum amyloid A-2 protein (SAA2)

Serum amyloid A-2 protein (SAA2) is a major acute-phase protein synthesized predominantly by the liver in response to pro-inflammatory cytokines such as interleukin-6 and tumor necrosis factor-α[2][4][5]. It is one of several closely related SAA isoforms in humans, most notably SAA1 and SAA2, which dramatically increase in circulation (up to 1,000-fold) during acute inflammation[5][6]. SAA2 participates in diverse biological activities, including recruitment of immune cells (chemotaxis via formyl peptide receptor 2), modulation of cytokine release, transport of cholesterol, and association with HDL[2][3][5][6]. Chronic overproduction of SAA2 is implicated in the pathogenesis of secondary (AA) amyloidosis, where SAA2-derived fibrils deposit in tissues and organs, leading to dysfunction in chronic inflammatory states such as rheumatoid arthritis[1][3][5]. SAA2 is also used as a sensitive clinical biomarker for systemic inflammatory response and disease activity in various conditions[5]. If additional highly specific or drug-targeting details become available (e.g., approved or in-development direct SAA2 inhibitors or new class effects), these should be added accordingly. Currently, therapeutic manipulation is largely indirect via control of underlying inflammation.

Other names

Serum amyloid A2Amyloid A2 proteinAA2SAA2SAASAA-2Serum amyloid A-2 protein

Drugs reduce SAA2 levels mainly by inhibiting upstream pro-inflammatory cytokines (e.g., IL-6 or TNF-α blockade). Certain therapeutics may limit SAA2’s contribution to amyloidogenesis and associated inflammation. SAA2 engages cell surface receptors such as the formyl peptide receptor 2 (FPR2), mediating downstream signaling and chemotaxis[6].