C3 and type 1 diabetes mellitus: Youth with T1DM had significantly higher protein levels of alpha-1B-glycoprotein (A1BG; P = 0.003), apolipoprotein A-IV (APOA4; P = 0.037), complement factor H (CFAH; P = 0.0488), factor H related protein 2 (FHR2; P = 0.0005), inter-alpha trypsin inhibitor 4 (ITIH4; P = 0.013), peptidoglycan recognition protein 2 (PGRP2; P = 0.017) and lower levels of albumin (ALBU; P = 0.027) and complement C3 (CO3; P = 0.015) compared to HC.