Based on our detailed measurements, diminished activation of F3-LP and AP in diabetic patients with bacterial infections was not due to lower levels of ficolins, C4 or C3, as antigenic concentrations of these complement components were similar in the two groups, or even higher in case of C3 in the T2DM group, in accordance with previous data (42, 44). Here, C3 is linked to type 2 diabetes mellitus.