Studies on the Host Parasite Relationships to Schistosoma japonicum. V. Reactions in the Skin, Lungs and Liver of Normal and Immune Animals Following Infection with Schistosoma japonicum

1959 ◽  
Vol 45 (5) ◽  
pp. 549 ◽  
Author(s):  
Sung Sheng Lin ◽  
Elvio H. Sadun
Parasitology ◽  
1991 ◽  
Vol 103 (1) ◽  
pp. 77-83 ◽  
Author(s):  
M. Y. Xia ◽  
J. Jourdane

The routes of penetration and the strategies of invasion of Schistosoma japonicum miracidia in the snail vector Oncomelania hupensis were observed in a histological study. In all species of the genus Schistosoma, it is usually assumed that the miracidia achieve penetration through the tegument. Our results showed that at least 57% of S. japonicum miracidia penetrated the snail by natural openings (branchial cavity, mouth and rectum). Throughout the invasion phase, the larvae were observed in all the tissues and organs with the exception of the genital gland. The spatial distribution of parasites in the snail revealed that the migration towards the visceral organs such as the kidney, heart and sinuses (which are the most usual microhabitats of the mother sporocysts of S. japonicum) appeared to take place via the circulatory system. Using natural openings as routes for penetration probably provides a selective advantage in a host–parasite system in which the target mollusc is amphibious: we presume that the miracidia inside these natural openings are protected against desiccation when the snail leaves the water, and that they can subsequently invade the tissues.


PROTEOMICS ◽  
2007 ◽  
Vol 7 (3) ◽  
pp. 450-462 ◽  
Author(s):  
Feng Liu ◽  
Wei Hu ◽  
Shu-Jian Cui ◽  
Ming Chi ◽  
Cai-Yun Fang ◽  
...  

2006 ◽  
Vol 2 (4) ◽  
pp. e29 ◽  
Author(s):  
Feng Liu ◽  
Jiong Lu ◽  
Wei Hu ◽  
Sheng-Yue Wang ◽  
Shu-Jian Cui ◽  
...  

2001 ◽  
Vol 17 (7) ◽  
pp. 320-324 ◽  
Author(s):  
Yi-Xun He ◽  
Buz Salafsky ◽  
Kalyanasundaram Ramaswamy

Parasitology ◽  
1997 ◽  
Vol 114 (4) ◽  
pp. 383-393 ◽  
Author(s):  
M. WEBSTER ◽  
B. D. L. LIBRANDA-RAMIREZ ◽  
G. D. ALIGUI ◽  
R. M. OLVEDA ◽  
J. H. OUMA ◽  
...  

We have investigated the effects of host age and sex on human antibody isotype responses to Schistosoma mansoni and Schistosoma japonicum adult worm (AW) and soluble egg (SEA) antigens, using sera from subjects in Kenya and the Philippines. Similar trends with age were observed between the two populations despite host, parasite and environmental differences between the two geographical locations. IgE to AW increased with age, whereas most isotype responses to SEA decreased with age. IgG1, IgG3 and IgG4 subclass responses to adult worm, however, did not show a broadly rising or falling pattern with age. Males were found to have higher IgG1, IgG4 and IgE to AW in both populations. This sex difference remained significant in the Kenyan population even after controlling statistically for confounding factors such as age and differences in intensity of infection. Analysis of S. mansoni and S. japonicum adult worm antigens reactive with IgE revealed a predominant 22 kDa band in both parasites. Only those individuals with relatively high IgE titres specifically reactive with S. mansoni or S. japonicum AW had detectable IgE against Sj22 or Sm22.


1959 ◽  
Vol 124 (6) ◽  
pp. 428-436 ◽  
Author(s):  
E. H. Sadun ◽  
B. C. Walton

2020 ◽  
Vol 14 (10) ◽  
pp. e0008810
Author(s):  
Bingkuan Zhu ◽  
Fang Luo ◽  
Yi Shen ◽  
Wenbin Yang ◽  
Chengsong Sun ◽  
...  

Cercariae invasion of the human skin is the first step in schistosome infection. Proteases play key roles in this process. However, little is known about the related hydrolytic enzymes in Schistosoma japonicum. Here, we investigated the biochemical features, tissue distribution and biological roles of a cathepsin B cysteine protease, SjCB2, in the invasion process of S. japonicum cercariae. Enzyme activity analysis revealed that recombinant SjCB2 is a typical cysteine protease with optimum temperature and pH for activity at 37°C and 4.0, respectively, and can be totally inhibited by the cysteine protease inhibitor E-64. Immunoblotting showed that both the zymogen (50 kDa) and mature enzyme (30.5 kDa) forms of SjCB2 are expressed in the cercariae. It was observed that SjCB2 localized predominantly in the acetabular glands and their ducts of cercariae, suggesting that the protease could be released during the invasion process. The protease degraded collagen, elastin, keratin, fibronectin, immunoglobulin (A, G and M) and complement C3, protein components of the dermis and immune system. In addition, proteomic analysis demonstrated that SjCB2 can degrade the human epidermis. Furthermore, it was showed that anti-rSjCB2 IgG significantly reduced (22.94%) the ability of the cercariae to invade the skin. The cysteine protease, SjCB2, located in the acetabular glands and their ducts of S. japonicum cercariae. We propose that SjCB2 facilitates skin invasion by degrading the major proteins of the epidermis and dermis. However, this cysteine protease may play additional roles in host-parasite interaction by degrading immunoglobins and complement protein.


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