Proteomic Analysis on Cercariae and Schistosomula in Reference to Potential Proteases Involved in Host Invasion of Schistosoma japonicum Larvae

• Published in: Journal of proteome research Vol. 14; no. 11; pp. 4623 - 4634
• Main Authors: Liu, Mu, Ju, Chuan, Du, Xiao-Feng, Shen, Hai-Mo, Wang, Ji-Peng, Li, Jian, Zhang, Xu-Min, Feng, Zheng, Hu, Wei
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 06.11.2015
• Subjects: Amino Acid Sequence; Animals; Cercaria - genetics; Cercaria - growth & development; Cercaria - metabolism; Chromatography, Liquid; Cysteine Proteases - chemistry; Cysteine Proteases - genetics; Cysteine Proteases - metabolism; Escherichia coli - genetics; Escherichia coli - metabolism; Female; Gene Expression; Helminth Proteins - chemistry; Helminth Proteins - genetics; Helminth Proteins - metabolism; Life Cycle Stages - genetics; Mice; Mice, Inbred C57BL; Molecular Sequence Annotation; Molecular Sequence Data; Peptide Fragments - isolation & purification; Proteolysis; Proteome - chemistry; Proteome - genetics; Proteome - metabolism; Recombinant Proteins - chemistry; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Schistosoma japonicum - genetics; Schistosoma japonicum - growth & development; Schistosoma japonicum - metabolism; Serine Endopeptidases - chemistry; Serine Endopeptidases - genetics; Serine Endopeptidases - metabolism; Skin - parasitology; Snails - parasitology; Tandem Mass Spectrometry; protease; proteomics; cercariae; cercarial transformation; schistosomula; Schistosoma japonicum; invasion process
• ISSN: 1535-3893; 1535-3907
• DOI: 10.1021/acs.jproteome.5b00465

Schistosomiasis is a parasitic zoonosis posing great threat to human health. The infection is acquired by larval cercariae penetrating host skin and transforming into juveniles, schistosomula. Proteolytic enzymes secreted from the cercarial acetabular glands are known to aid to the skin penetration, but molecular mechanisms remain largely unclear. To profile the protein composition and identify potential invasive proteases, we developed a new method for simulating cercarial transformation and collecting schistosomula, and for the first time, we compared the proteomes of Schistosoma japonicum cercariae and schistosomula by using in-gel shotgun proteomic analysis. Totally, 1972 proteins were identified in association with ten main biological processes based on Gene Ontology analysis; 46 proteases were detected in cercariae, and among them, 25 proteases disappeared after penetrated. Notably, leishmanolysins and serine and cysteine proteases were found abundant but differentially expressed. Recombinant serine protease SjCE2b and cysteine protease SjCB2 were produced and used for validation of native proteins. Immunofluorescence and Western blotting assays detected SjCE2b and SjCB2 in cercariae but not in schistosomula, suggesting the two enzymes might be consumed upon skin migration. Our data comprehensively chart the proteomic changes during cercarial invasion, revealing the potential proteases involved, providing a platform for the development of molecular anti-infection strategy.