We and others have shown that the lectin pathway, followed by activation of the complement system, plays an important role in complications of T1D [6,7,8,13,40,41], the development of diabetic kidney disease [6,42], and high serum MBL levels are associated with the development of end-stage renal disease in patients with diabetic nephropathy [43]. Here, MBL2 is linked to type 1 diabetes mellitus.