Function
Mannose-binding protein (MBL) or Mannose-binding lectin or Mannan-binding lectin is a lectin essential to innate immunity. MBL recognizes carbohydrate patterns like mannose or glucose located on the surface of microorganisms like bacteria, viruses and fungi. MBL binds to the microorganism and the activation of the lectin pathway ensues. MBL binds to apoptotic and senescent cells and enhances their engulfment by phagocytes. In the blood, MBL is bound to MBL-associated serine protease (MASP-2). Upon binding of MBL to a target mannose, the MASP initiates the complement cascade resulting in lysis of the pathogen[1].
Disease
MBL deficiency is associated with poor outcome of cystic fibrosis patients[2]. MBL deficiency is one of the most common human immunodeficiencies and arise primarily from 3 single point mutations in the MBL gene[3].
Structural highlights
[4].
