Cloning and expression of a Trichinella spiralis putative glutathione S-transferase and its elicited protective immunity against challenge infections

• Published in: Parasites & vectors Vol. 10; no. 1; p. 448
• Main Authors: Liu, Chun Ying, Song, Yan Yan, Ren, Hua Na, Sun, Ge Ge, Liu, Ruo Dan, Jiang, Peng, Long, Shao Rong, Zhang, Xi, Wang, Zhong Quan, Cui, Jing
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 29.09.2017; BioMed Central; BMC
• Subjects: Adults; Amino acid sequence; Amino acids; Animals; Antibodies; Antibodies, Helminth - immunology; Antigenicity; Antigens; Cloning; Cloning, Molecular; Detoxification; E coli; Enzymatic activity; Enzyme-linked immunosorbent assay; Female; Gene expression; Genetic aspects; Genotypes; Glutathione; Glutathione transferase; Glutathione Transferase - administration & dosage; Glutathione Transferase - genetics; Glutathione Transferase - immunology; Glutathione-S-transferase (GST); Health aspects; Helminth Proteins - administration & dosage; Helminth Proteins - genetics; Helminth Proteins - immunology; Hogs; Humans; Immune response; Immune system; Immunity; Immunization; Immunoglobulin G; Infections; Intestine; Larvae; Lymphocytes T; Mice; Mice, Inbred BALB C; Parasites; Parasitic diseases; Polymerase chain reaction; Protective immunity; Reduction; Schistosoma mansoni; Spectrophotometry; Trichina worm; Trichinella spiralis; Trichinella spiralis - genetics; Trichinella spiralis - immunology; Trichinellosis - immunology; Trichinellosis - parasitology; Trichinellosis - prevention & control; Tropical diseases; Vaccination; Vaccines; Vaccines - administration & dosage; Vaccines - genetics; Vaccines - immunology; Wuchereria bancrofti; China; Mice; Trichinella spiralis; Protective immunity; Glutathione-S-transferase (GST)
• ISSN: 1756-3305; 1756-3305
• DOI: 10.1186/s13071-017-2384-1

Glutathione-S-transferase (GST) is a widespread multigene family of detoxification enzymes. The vaccination of mice with recombinant GST of 24 kDa from Trichinella spiralis elicited a low immune protection against challenge infection. The objective of this study was to characterize the T. spiralis putative GST gene (TspGST) encoding a 30.8 kDa protein and to evaluate its potential as a candidate antigen for anti-Trichinella vaccine. The full-length cDNA sequence of TspGST from T. spiralis muscle larvae (ML) was expressed in E. coli. The enzymatic activity and antigenicity of the rTspGST were identified by spectrophotometry, Western blot, and ELISA. The expression of TspGST at T. spiralis various stages was investigated by RT-PCR and indirect immunofluorescent test (IIFT). Serum level of total IgG, IgG1, and IgG2a antibodies against rTspGST were measured by ELISA. The immune protection produced by vaccination with rTspGST against T. spiralis was evaluated. The sequencing results showed that the cDNA of TspGST was 840 bp, and encoded a protein of 279 amino acids, which had a molecular size of 30.8 kDa and a pI of 5.21. Its amino acid sequence shares 37% similarity with TsGST. The rTspGST protein had enzymatic activity of GST. On Western blot and ELISA analysis, the native TspGST protein with 30.8 kDa in crude antigens derived from adult worms (AW), newborn larvae (NBL), infective intestinal larvae (IIL) and ML was recognized by anti-rTspGST sera, but the ML ES antigens could be not recognized by anti-rTspGST sera. Expression of TspGST was found in all of T. spiralis various stages (AW, NBL, ML, and IIL). An immunolocalization analysis identified TspGST in different stages (mainly in cuticles) of the nematode. The mice vaccinated with the rTspGST elicited Th2-predominant immune responses, showed a 34.38% reduction of adult worms and a 43.70% reduction of muscle larvae. Immunization with rTspGST produced a partial immune protection, and the rTspGST could be regarded as a potential candidate target for an anti-Trichinella vaccine.