Schistosoma japonica remains endemic in seven provinces in China. Human infection is acquired during the course of domestic or occupational activities, in particular fishing and farming. Acute infection may result in fever, weakness, diarrhoea, abdominal pain and hepatomegaly. Chronic disease involves granuloma formation, tissue inflammation, liver lesions and fibrosis, which may persist after infection has been cleared. Schistosoma japonicum is also known to infect 45 species of animals, of which water buffaloes are especially important for transmission (Balen et al., 2007).
Protein Note :
Ribonuclease T2 (RNase T2) is a widespread family of secreted RNases found in every organism examined thus far. This family includes RNase Rh, RNase MC1, RNase LE, and self-incompatibility RNases (S-RNases). Plant T2 RNases are expressed during leaf...; cd01061
Efficacy:
In three separate experiments, pCMV-Sjc97, inoculated intramuscularly three times at doses of 100 or 200 μg per C57BL/6 mouse, was found to provide significant worm reduction rates. In addition, there was a substantial reduction in the number of eggs present in the livers and spleens of the pCMV-Sjc97 immunized group when compared with the pCMV blank vector control groups. Therefore, preliminary results suggest pCMV-Sjc97 can confer protective immunity in C57BL/6 mice (Zhou et al., 2000).
2. Chinese S. japonicum DNA vaccine pVAX/SjFABP encoding FABP
Efficacy:
The mice inoculated intramuscularly with pVAX/SjFABP showed significant worm reduction rate of 22.94% (P < 0.05) and egg reduction rate of 30.23% when compared with the pVAX1 control group. The addition of the pVAX/mIL-18 plasmids dramatically enhanced protection with worm reduction rate of 36.92% and egg reduction rate of 43.23% (P < 0.05), compared to the pVAX/SjFABP group (Wei et al., 2009).
3. Chinese S. japonicum DNA vaccine pVIVO2-IL12-Sj23 encoding Sj23 and IL-12
Efficacy:
A 45.53% reduction in worm burden as well as a 58.35% egg reduction rate were found in mice vaccinated with pVIVO2-IL12-Sj23. The multivalent DNA vaccine pVIVO2-IL12-Sj23 induced stronger protection than the monovalent vaccine pVIVO2-Sj23 (P<0.05) (Gan et al., 2004).
Efficacy:
This vaccine produced a 51.2% reduction in worm burden, 61.5% liver egg reduction, 52.1% fecal egg reduction and 52.1% reduction in fecal miracidia (Da'dara et al., 2008).
The bacterium Streptococcus gordonii is used as the vaccine vector, with the Streptococcus pyogenes protein M6 designed to surface-localize the S. japonicum antigen on S. gordonii (Wang et al., 2013).
e. Immunization Route
intranasal immunization
f. Description
Because chemotherapy is currently the main effective method to treat schistosomiasis, but it doesn't prevent reinfection, there has been a need to create a vaccine that can safely express the pathogenic antigen and elicit protection against the disease. This vectored vaccine has been shown to partially protect laboratory mice from S. japonicum challenge, making it a good candidate for schistosomiasis prevention (Wang et al., 2013).
g.
Mouse Response
Vaccine Immune Response Type:
VO_0000287
Immune Response:
The mice inoculated with the vaccine showed strong serum IgG, serum IgA, and saliva IgA antibodies against the antigen Sj-F1 (Wang et al., 2013).
Challenge Protocol:
The mice were challenged with the cercariae (parasitic larva) of S. japonicum (Wang et al., 2013).
Efficacy:
The mice immunized with the vaccine showed "significant protection" including a 21.45% reduction in the number of parasitic worms present and a 34.77% reduction in the number of eggs (Wang et al., 2013).
Description:
The protection received shows that the S. gordonii vector expressing S. japonicum is highly immunogenic and has potential to become a safe, effective vaccine against schistosomiasis (Wang et al., 2013).
Replication-defective adenoviral vector-based vaccine with optimized SjTPI (rAdV-SjTPI.opt) (Dai et al., 2014).
f. Immunization Route
Intramuscular injection (i.m.)
g.
Mouse Response
Vaccination Protocol:
Mice were randomly divided into different vaccination groups (16 mice/group) for intramuscular (i.m.), subcutaneous (s.c.) and oral immunization (o.i.). Groups consisted of vaccination with the adenoviral vector alone or without vaccination were used as vector or normal control, respectively (Dai et al., 2014).
Vaccine Immune Response Type:
VO_0003057
Challenge Protocol:
Each mouse was challenged with 40 ± 1 S. japonicum cercariae by abdominal skin penetration two weeks after the last vaccination (Dai et al., 2014).
Efficacy:
Results showed that intramuscular rAdV-SjTPI.opt induced Th1 biased immune responses in the host, while subcutaneous rAdV-SjTPI.opt induced Th2 predominant immune responses. Oral rAdV-SjTPI.opt induced low levels of immune responses and no significant protection. Intramuscular rAdV-SjTPI.opt provided a consistent and repeatable higher protective effect in mice (Dai et al., 2014).
1. Balen et al., 2007: Balen J, Zhao ZY, Williams GM, McManus DP, Raso G, Utzinger J, Zhou J, Li YS. Prevalence, intensity and associated morbidity of Schistosoma japonicum infection in the Dongting Lake region, China. Bulletin of the World Health Organization. 2007; 85(7); 519-526. [PubMed: 17768500].
2. Chen et al., 2016: Chen L, Chen Y, Zhang D, Hou M, Yang B, Zhang F, Zhang W, Luo X, Ji M, Wu G. Protection and immunological study on two tetraspanin-derived vaccine candidates against schistosomiasis japonicum. Parasite immunology. 2016; 38(10); 589-598. [PubMed: 27189226].
3. Da'dara et al., 2008: Da'dara AA, Li YS, Xiong T, Zhou J, Williams GM, McManus DP, Feng Z, Yu XL, Gray DJ, Harn DA. DNA-based vaccines protect against zoonotic schistosomiasis in water buffalo. Vaccine. 2008; 26(29-30); 3617-3625. [PubMed: 18524429].
4. Gan et al., 2004: Gan Y, Shi YE, Bu LY, Zhu XH, Ning CX, Zhu HG. Immune responses against Schistosoma japonicum after vaccinating mice with a multivalent DNA vaccine encoding integrated membrane protein Sj23 and cytokine interleukin-12. Chinese medical journal. 2004; 117(12); 1842-1846. [PubMed: 15603716].
5. Gao et al., 2017: Gao Y, Zhou X, Wang H, Liu R, Ye Q, Zhao Q, Ming Z, Dong H. Immunization with recombinant schistosome adenylate kinase 1 partially protects mice against Schistosoma japonicum infection. Parasitology research. 2017; 116(6); 1665-1674. [PubMed: 28455627].
6. Ke et al., 2017: Ke XD, Shen S, Song LJ, Yu CX, Kikuchi M, Hirayama K, Gao H, Wang J, Yin X, Yao Y, Liu Q, Zhou W. Characterization of Schistosoma japonicum CP1412 protein as a novel member of the ribonuclease T2 molecule family with immune regulatory function. Parasites & vectors. 2017; 10(1); 89. [PubMed: 28212670].
7. Wei et al., 2009: Wei F, Liu Q, Zhai Y, Fu Z, Liu W, Shang L, Men J, Gao S, Lian H, Jin H, Chen C, Lin J, Shi Y, Xia Z, Zhu XQ. IL-18 enhances protective effect in mice immunized with a Schistosoma japonicum FABP DNA vaccine. Acta tropica. 2009; 111(3); 284-288. [PubMed: 19467215].
8. Zhou et al., 2000: Zhou S, Liu S, Song G, Xu Y, Sun W. Protective immunity induced by the full-length cDNA encoding paramyosin of Chinese Schistosoma japonicum. Vaccine. 2000; 18(27); 3196-3204. [PubMed: 10856799].
