LMAN2 and type 2 diabetes mellitus: Level 3 confirmation. Mannose-binding lectin 2 (MBL2) is an important component of the innate, non-specific immunity, primarily produced by liver (Gadjeva et al., 2004). MBL2 deficiency is known to affect defense against infections (Thiel et al., 2006). Serum MBL levels are significantly elevated in patients with type 1 diabetes (Hansen et al., 2003), and elevated serum levels of MBL can indicate poor diabetic control in T2DM patients (Elawa et al., 2011).