title: Immune response induced by oral delivery of Bacillus subtilis spores expressing enolase of Clonorchis sinensis in grass carps (Ctenopharyngodon idellus).
abstract: Clonorchiasis, caused by the consumption of raw or undercooked freshwater fish containing infective metacercariae of Clonorchis sinensisis (C.sinensis), remains a common public health problem. New effective prevention strategies are still urgent to control this food-borne infectious disease. The previous studies suggested Bacillus subtilis (B. subtilis) spores was an ideal vaccines delivery system, and the C.sinensis enolase (CsENO) was a potential vaccine candidate against clonorchiasis. In the current study, we detected CsENO-specific IgM levels by ELISA in sera, intestinal mucus and skin mucus in grass carps (Ctenopharyngodon idella) through oral administration with B. subtilis spores surface expressing CsENO. In addition, immune-related genes expression was also measured by qRT-PCR. Grass carps orally treated with B. subtilis spores or normal forages were used as controls. The results of ELISA manifested that specific IgM levels of grass carps in CsENO group in sera, intestine mucus and skin mucus almost significantly increased from week 4 post the first oral administration when compared to the two control groups. The levels of specific IgM reached its peak in intestine mucus firstly, then in sera, and last in skin mucus. qRT-PCR results showed that 5 immune-related genes expression had different degree of rising trend in CsENO group when compared to the two control groups. Our study demonstrated that orally administrated with B. subtilis spores expressing CsENO induced innate and adaptive immunity, systemic and local mucosal immunity, and humoral and cellular immunity. Our work may pave the way to clarify the exact mechanisms of protective efficacy elicited by B. subtilis spores expressing CsENO and provide new ideas for vaccine development against C. sinensis infection.
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Hongye
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Tingjin
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Hengchang
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Zeli
authors.initials: Z
authors.lastname: Tang
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Jinyun
authors.initials: J
authors.lastname: Yu
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Zhipeng
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Pengli
authors.initials: P
authors.lastname: Ren
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China.
authors.forename: Xuerong
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Key Laboratory for Tropical Diseases Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong 510080, China. Electronic address: yuxb@mail.sysu.edu.cn.
authors.forename: Xinbing
authors.initials: X
authors.lastname: Yu
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D001412:Bacillus subtilis / Q000235:genetics / Q000276:immunology; D002347:Carps; D003003:Clonorchiasis / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D003004:Clonorchis sinensis / Q000201:enzymology* / Q000235:genetics / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005393:Fish Diseases / Q000276:immunology* / Q000469:parasitology / Q000517:prevention & control; D015801:Helminth Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D007109:Immunity; D010751:Phosphopyruvate Hydratase / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D013171:Spores, Bacterial / Q000235:genetics / Q000276:immunology; D014612:Vaccines / Q000276:immunology*
chemical_list: D000909:Antibodies, Helminth; D015801:Helminth Proteins; D014612:Vaccines; D010751:Phosphopyruvate Hydratase
keywords: Bacillus subtilis spore; Clonorchis sinensis; Enolase; Grass carp (Ctenopharyngodon idella); Oral administration