title: The C-reactive protein of tongue sole Cynoglossus semilaevis is an acute phase protein that interacts with bacterial pathogens and stimulates the antibacterial activity of peripheral blood leukocytes.
abstract: Pentraxins are a family of evolutionarily conserved proteins that play an important part in innate immunity. C-reactive protein (CRP) is a member of the pentraxin family and in humans is known to be the major acute phase protein. In this work, we report the identification and analysis of a CRP, CsCRP, from half-smooth tongue sole (Cynoglossus semilaevis). CsCRP is composed of 228 amino acid residues and possesses a Pentraxin/CRP domain. Expression of CsCRP occurred in a wide range of tissues and was upregulated by pathogen infection in kidney, spleen, blood, and, in particular, liver. Following bacterial infection, CsCRP level in blood rose rapidly within 12 h and was approximately 3.8 fold of that of the basal level. Purified recombinant CsCRP (rCsCRP) was able to interact with Gram-negative and Gram-positive bacteria including those of pathogenic nature in a dose-dependent manner. When peripheral blood leukocytes (PBL) were infected with bacterial pathogen in the presence of rCsCRP, the respiratory burst and phagocytic capacity of the cells were increased to significant extents. Taken together, these results indicate that CsCRP is an acute phase protein that plays a role in innate immune defense against bacterial infection.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
authors.forename: Mo-fei
authors.initials: MF
authors.lastname: Li
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Sun
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001419:Bacteria / Q000276:immunology* / Q000378:metabolism; D001483:Base Sequence; D002097:C-Reactive Protein / Q000276:immunology* / Q000378:metabolism; D003001:Cloning, Molecular; D005412:Flatfishes / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D005786:Gene Expression Regulation / Q000276:immunology*; D007113:Immunity, Innate / Q000276:immunology*; D007962:Leukocytes / Q000276:immunology*; D008969:Molecular Sequence Data; D010587:Phagocytosis / Q000276:immunology; D010957:Plasmids / Q000235:genetics; D017434:Protein Structure, Tertiary; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D016897:Respiratory Burst / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA / Q000662:veterinary
chemical_list: D002097:C-Reactive Protein