Review

Virologica Sinica

, Volume 29, Issue 1, pp 25-32

Ficolins and infectious diseases

  • Yushan RenAffiliated withState Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University School of Medicine
  • , Quanquan DingAffiliated withState Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University School of Medicine
  • , Xiaolian ZhangAffiliated withState Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University School of Medicine Email author 

Abstract

Ficolins are serum complement lectins, with a structure similar to mannose-binding lectin (MBL) and lung surfactant protein (SP)-A and SP-D. Ficolins activate the lectin complement system and play important roles in host innate immunity. Ficolins are members of the collectin family of proteins, which act as pattern recognition receptors (PRRs). They are soluble oligomeric defense proteins with lectin-like activity, and are able to recognize pathogen-associated molecular patterns (PAMPs), which are carbohydrate molecules on the surface of pathogens, and of apoptotic, necrotic, and malignant cells. Upon binding to their specific PAMPs, ficolins may trigger activation of the immune system either (1) by initiating activation of complement via the lectin pathway, (2) by a primitive type of opsonophagocytosis, or (3) by stimulating secretion of the inflammatory cytokines interferon (IFN)-Γ, interleukin (IL)-17, IL-6, and tumor necrosis factor (TNF)-α, and production of nitric oxide (NO) by macrophages, thus limiting the infection and concurrently orchestrating the subsequent adaptive immune response. Recently, a number of reports have shown that dysfunction or abnormal expression of ficolins may play crucial roles in viral and bacterial diseases and in inflammation. This review summarizes the reports on the roles of ficolins in the infectious diseases, and provides insight into ficolins as novel innate immune therapeutic options to treat these diseases.

Keywords

L-ficolin H-ficolin M-ficolin virus bacteria