Plasma levels of mannan-binding lectin-associated serine proteases MASP-1 and MASP-2 are elevated in type 1 diabetes and correlate with glycaemic control

Clin Exp Immunol. 2015 May;180(2):227-32. doi: 10.1111/cei.12574.


There is increasing evidence that the complement system plays an important role in diabetes and the development of diabetic vascular complications. In particular, mannan-binding lectin (MBL) levels are elevated in diabetes patients, and diabetes patients with diabetic nephropathy have higher MBL levels than diabetes patients with normal renal function. The MBL-associated serine proteases (MASPs) MASP-1, MASP-2 and MASP-3 and MBL-associated protein MAp44 have not yet been studied in diabetes patients. We therefore measured plasma levels of MASP-1, MASP-2, MASP-3 and MAp44 in 30 children with type 1 diabetes mellitus (T1DM) and 17 matched control subjects, and in 45 adults with T1DM and 31 matched control subjects. MASP-1 and MASP-2 levels were significantly higher in children and adults with T1DM than in their respective control groups, whereas MASP-3 and MAp44 levels did not differ between patients and controls. MASP-1 and MASP-2 levels correlated with HbA1c, and MASP levels decreased when glycaemic control improved. Because MASP-1 and MASP-2 have been shown to interact directly with blood coagulation, elevated levels of these proteins may play a role in the enhanced thrombotic environment and consequent vascular complications in diabetes.

Keywords: MASP-1; MASP-2; diabetes; mannan-binding lectin-associated serine proteases.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Blood Coagulation / immunology
  • Child
  • Child, Preschool
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / drug therapy
  • Diabetes Mellitus, Type 1 / immunology*
  • Diabetic Angiopathies / blood
  • Diabetic Angiopathies / immunology
  • Female
  • Glycated Hemoglobin / immunology
  • Glycated Hemoglobin / metabolism
  • Humans
  • Male
  • Mannose-Binding Protein-Associated Serine Proteases / immunology*
  • Mannose-Binding Protein-Associated Serine Proteases / metabolism
  • Thrombosis / blood
  • Thrombosis / immunology


  • Glycated Hemoglobin A
  • hemoglobin A1c protein, human
  • MASP1 protein, human
  • MASP2 protein, human
  • Mannose-Binding Protein-Associated Serine Proteases