Emerging role of ficolins in autoimmune diseases

[Display omitted] •Ficolins form complexes with mannose-binding lectin-associated serine proteases (MASPs) to trigger complement activation.•Ficolins regulate homeostasis by mediating immune responses of opsonization, phagocytosis and cytokine production.•Emerging evidence has suggested the major role of ficolins in the onset and development of autoimmune diseases (ADs). Ficolins are pattern-recognition molecules (PRMs) that could form complexes with mannose-binding lectin-associated serine proteases (MASPs) to trigger complement activation via the lectin pathway, thereby mediating a series of immune responses including opsonization, phagocytosis and cytokine production. In the past few decades, accumulating evidence have suggested that ficolins play a major role in the onset and development of several autoimmune diseases (ADs), including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc), Type 1 diabetes (T1D), inflammatory bowel disease (IBD), etc. In this review, we synthesized previous literatures and recent advances to elucidate the immunological regulations of ficolins and discuss the potential diagnostic ability of ficolins in ADs, as well as giving an insight into the future therapeutic options for ficolins in ADs.