title: C5a of Cynoglossus semilaevis has anaphylatoxin-like properties and promotes antibacterial and antiviral defense.
abstract: Activation of the complement system leads to the cleavage of component factor C5 into C5a and C5b. C5a can induce chemotaxis and inflammatory responses in mammals. The function of C5a in fish is poorly understood. In this study, we report the identification and analysis of a C5 homologue, CsC5, from tongue sole (Cynoglossus semilaevis). CsC5 is composed of 1683 amino acid residues that include an anaphylatoxin homologous domain. Expression of CsC5 could be detected in a variety of tissues and was up-regulated by bacterial or viral pathogen infection. Purified recombinant CsC5a (rCsC5a) could bind to peripheral blood leukocytes (PBL) and stimulate PBL chemotaxis, proliferation, respiratory burst, acid phosphatase activity, and phagocytosis. Tongue sole administered rCsC5a exhibited enhanced resistance against bacterial and viral infections. These results indicate that CsC5a is an anaphylatoxin with a role in innate immune defense against bacterial and viral infections.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
authors.forename: Mo-fei
authors.initials: MF
authors.lastname: Li
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China. Electronic address: huyonghua@qdio.ac.cn.
authors.forename: Yong-hua
authors.initials: YH
authors.lastname: Hu
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000595:Amino Acid Sequence; D000706:Anaphylatoxins / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D002633:Chemotaxis; D015936:Complement C5a / Q000494:pharmacology / Q000502:physiology*; D017124:Conserved Sequence; D004926:Escherichia coli / Q000276:immunology; D005393:Fish Diseases / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D029941:Fish Proteins / Q000494:pharmacology / Q000502:physiology*; D005412:Flatfishes; D007113:Immunity, Innate / Q000187:drug effects; D007668:Kidney / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology / Q000382:microbiology; D009928:Organ Specificity; D010587:Phagocytosis / Q000187:drug effects; D013154:Spleen / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D014733:Vibrio / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000706:Anaphylatoxins; D029941:Fish Proteins; D015936:Complement C5a
keywords: Antibacterial; Antiviral; Complement factor 5; Cynoglossus semilaevis; Peripheral blood leukocytes