title: Schistosoma japonicum egg specific protein SjE16.7 recruits neutrophils and induces inflammatory hepatic granuloma initiation.
abstract: Neutrophils are known to play a major role in the egg granulomatous lesions caused by Schistosoma japonicum, but the precise mechanism by which eggs recruit or active neutrophil is unknown. Here we report S. japonicum egg specific EF-hand protein-SjE16.7 is a potent neutrophil recruiter and initiates the egg associated inflammatory granuloma in schistosomiasis. We show that the expression of SjE16.7 at level of both mRNA and protein is restricted to the egg stage. It locates in the miracidium and subshell area of the egg and can be secreted by the egg. The antigenic properties of SjE16.7 strongly suggest a role for SjE16.7 as an egg-derived molecule involved in host-parasite interactions. To study SjE16.7 functions in vivo, we challenged murine air pouch with recombinant SjE16.7. The results showed SjE16.7 trigged more inflammatory cell infiltration than vehicle or control protein. Using peritoneal exudate neutrophils from mice, we found that SjE16.7 significantly induced neutrophil chemotaxis in vitro, and the observed phenotypes were associated with enhanced Rac GTPase activation in SjE16.7 treated cells. Finally, in vivo hepatic granuloma formation model showed SjE16.7 coupled beads recruited more inflammatory cell infiltration than control beads. Our findings suggest SjE16.7 is an important pathogenic factor derived from egg. By recruiting neutrophils and inducing local inflammation, SjE16.7 facilitates eggs to be excreted through gut tissues and also initiates pathology in the liver; therefore SjE16.7 is a possible target for the prevention and treatment of schistosomiasis.
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Chenyun
authors.initials: C
authors.lastname: Wu
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Wu
authors.affiliation: Institute of Health Sciences, Shanghai Institutes for Biological Sciences of Chinese Academy of Sciences/Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Han
authors.affiliation: Institute of Health Sciences, Shanghai Institutes for Biological Sciences of Chinese Academy of Sciences/Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: The Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chu
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Linping
authors.initials: L
authors.lastname: Tan
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Xiaokui
authors.initials: X
authors.lastname: Guo
authors.affiliation: Department of Microbiology and Microbial Engineering, School of Life Science, Fudan University, Shanghai, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.affiliation: Department of Microbiology and Parasitology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Zhaojun
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D003001:Cloning, Molecular; D005260:Female; D006099:Granuloma / Q000139:chemically induced*; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D006790:Host-Parasite Interactions / Q000187:drug effects / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D020556:Neutrophil Infiltration / Q000187:drug effects; D009504:Neutrophils / Q000187:drug effects*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D012549:Schistosoma japonicum / Q000737:chemistry / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D000947:Antigens, Helminth; D015801:Helminth Proteins; D011994:Recombinant Proteins