APOC4 and type 1 diabetes mellitus: Throughout the study, distinct differences were observed between children who developed T1D and their controls: lower levels of apolipoprotein C-II (APOC2), apolipoprotein C-IV (APOC4), and mannose-binding protein C (MBL2); and higher levels of complement factor H-related protein 5 (FHR-5) and complement component C9 (CO9).