title: Biochemical and immunological characterization of annexin B30 from Clonorchis sinensis excretory/secretory products.
abstract: Clonorchis sinensis has been classified as group I biological carcinogen for cholangiocarcinoma by the World Health Organization. Biological studies on excretory/secretory products (ESPs) enabled us to understand the pathogenesis mechanism of C. sinensis and develop new strategies for the prevention of clonorchiasis. In this study, sequence analysis showed that annexin B30 from C. sinensis (CsANXB30) is composed of four annexin repeats which were characterized by type II and III Ca(2+)-binding sites or KGD motif with the capability of Ca(2+)-binding. In addition, immunoblot assay revealed that recombinant CsANXB30 (rCsANXB30) could be recognized by the sera from rats infected with C. sinensis and the sera from rats immunized by CsESPs. Real-time PCR showed that its transcriptional level was the highest at the stage of metacercaria. Immunofluorescence assay was employed to confirm that CsANXB30 was distributed in the tegument, intestine, and egg of adult worms, as well as the tegument and vitellarium of metacercaria. rCsANXB30 was able to bind phospholipid in a Ca(2+)-dependent manner and human plasminogen in a dose-dependent manner. Moreover, cytokine and antibody measurements indicated that rats subcutaneously immunized with rCsANXB30 developed a strong IL-10 production in spleen cells and a high level of IgG1 isotype, indicating that rCsANXB30 could trigger specific humoral and cellular immune response in rats. The present results implied that CsANXB30 might be involved in a host-parasite interaction and affected the immune response of the host during C. sinensis infection.
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China, helei668988@126.com.
authors.forename: Lei
authors.initials: L
authors.lastname: He
authors.forename: Mengyu
authors.initials: M
authors.lastname: Ren
authors.forename: Xueqing
authors.initials: X
authors.lastname: Chen
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Wang
authors.forename: Shan
authors.initials: S
authors.lastname: Li
authors.forename: Jinsi
authors.initials: J
authors.lastname: Lin
authors.forename: Chi
authors.initials: C
authors.lastname: Liang
authors.forename: Pei
authors.initials: P
authors.lastname: Liang
authors.forename: Yue
authors.initials: Y
authors.lastname: Hu
authors.forename: Huali
authors.initials: H
authors.lastname: Lei
authors.forename: Meng
authors.initials: M
authors.lastname: Bian
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.forename: Zhongdao
authors.initials: Z
authors.lastname: Wu
authors.forename: Xuerong
authors.initials: X
authors.lastname: Li
authors.forename: Xinbing
authors.initials: X
authors.lastname: Yu
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D017302:Annexins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D000909:Antibodies, Helminth / Q000096:biosynthesis*; D003003:Clonorchiasis / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control*; D003004:Clonorchis sinensis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015801:Helminth Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D006790:Host-Parasite Interactions; D006801:Humans; D007114:Immunization; D007074:Immunoglobulin G / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis; D008969:Molecular Sequence Data; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D011994:Recombinant Proteins; D016415:Sequence Alignment; D013154:Spleen / Q000166:cytology / Q000276:immunology
chemical_list: D017302:Annexins; D000909:Antibodies, Helminth; D015801:Helminth Proteins; D007074:Immunoglobulin G; D011994:Recombinant Proteins; D016753:Interleukin-10