Molecular identification of Trichinella spiralis nudix hydrolase and its induced protective immunity against trichinellosis in BALB/c mice

Abstract

BackgroundNudix hydrolases (Nd) is a widespread superfamily, which is found in all classes of organism, hydrolyse a wide range of organic pyrophosphates and has a ‘housecleaning’ function. The previous study showed that Trichinella spiralis Nd (TsNd) bound to intestinal epithelial cells (IECs), and the vaccination of mice with T7 phage-displayed TsNd polypeptides produced protective immunity. The aim of this study was to clone, express and identify the full-length TsNd and to investigate its immune protection against T. spiralis infection.MethodsThe full-length cDNA sequence of TsNd gene encoding a 46 kDa protein from T. spiralis intestinal infective larvae (IIL) was cloned and identified. The antigenicity of rTsNd was analyzed by Western blot. Transcription and expression of TsNd at T. spiralis different stages were observed by RT-PCR and IFT. The levels of the specific total IgG, IgG1 and IgG2a antibodies to rTsNd were determined by ELISA. The immune protection of rTsNd against T. spiralis infection was investigated.ResultsSequence and phylogenetic analysis revealed that TsNd had a nudix motif located at 226-244aa, which had high homology and the closest evolutionary status with T. pseudospiralis. The rTsNd was obtained after expression and purification. Western blot analysis showed that anti-rTsNd serum recognized the native TsNd protein in crude antigens of muscle larvae (ML), IIL, adult worms (AW) and newborn larvae (NBL), and ES antigens of ML. Transcription and expression of TsNd gene was observed in all developmental stages of T. spiralis (ML, IIL, AW and NBL), with high level expression in IIL. An immunolocalization analysis identified TsNd in the cuticle, stichocytes and reproductive organs of the parasite. Following immunization, anti-rTsNd IgG levels were increased, and the levels of IgG1 were more significantly higher than that of IgG2a. After a challenge infection with T. spiralis, mice immunized with the rTsNd displayed a 57.7% reduction in adult worms and a 56.9% reduction in muscle larval burden.ConclusionsTsNd induced a partial protective immunity in mice and could be considered as a novel candidate vaccine antigen against trichinellosis.

Vaccination against Trichinella spiralis: Potential, Limitations and Future Directions

“…Vaccination of mice with pcDNA3.1-TsNd showed 40.44% reduction in worm adults and 53.9% reduction in ML burden with the production of a mixed Th1/Th2 systemic immune response and IgA production at the mucosal level [54]. In this case, the use of pcDNA3.1/TsNd did not increase the protection previously conferred by recombinant TsNd (57.7 and 56.9% reduction in adult and ML burden, respectively) [44].…”

“…spiralis protein Nudix hydrolase (TsNd) is an up-regulated gene in IIL compared to ML. Recombinant TsNd emulsified with CFA displayed in mice a 57.7 and 56.9% reduction in adult worms and in ML burden, respectively, after a challenge infection with T. spiralis with high IgG1 levels [44].…”

Influence of adjuvant formulation on inducing immune response in mice immunized with a recombinant serpin from Trichinella spiralis

“…As the component of antigen is complex and changes constantly at the three major antigenic stages of T. spiralis , a single molecule was considered not enough to induce effective immunity against T. spiralis . Several recombinant protein antigens have been found to show partial protection against T. spiralis infection . It was proved that the protective effect of these genes could be significantly improved by choosing proper methods, such as constituting DNA vaccine or using a prime‐boost strategy .…”

Molecular cloning and characterization of a Spirometra erinacei casein kinase I

“…The final PCR products were purified, digested, and cloned into the pGEM-T vector (Promega, USA), subsequently sub-cloned into the expression vector pQE-80L (New England Biolabs, USA). Expression of the recombinant SeCP protein (rSeCKI) was induced by adding 0.1 mM IPTG at 37°C for 3 h. The rSeCKI was purified by Amylose Pre-packed Column (NEB Ltd, China) and analyzed by SDS-PAGE (Long et al 2014). Images of gels were recorded using ImageScanner (GE Healthcare, Fairfield, CT).…”