Original Article

Cloning and Expression of a New Trichinella spiralis Serine Protease and Its Role in Invading Host Intestinal Epithelium

Abstract

Background: In previous studies, a new Trichinella spiralis serine protease 1.1 (TsSP1.1) was identified in surface proteins of T. spiralis muscle larvae (ML) by proteomics analysis, but its functions in T. spiralis infection are unknown. The aim of this study was to investigate the roles of TsSP1.1 during larval intrusion of gut epithelium.

Methods: From January 2019 to March 2021, complete TsSP1.1 cDNA sequence was cloned and expressed in Escherichia coli BL21 at the Department of Parasitology, Medical College of Zhengzhou University, Zhengzhou, China. Expression and location of TsSP1.1 in the parasite were investigated using indirect immunofluorescence assay (IIFA) and Western blotting. The in vitro intestinal epithelium cells (IECs) intrusion assay was used to ascertain the roles of TsSP1.1 during larval intrusion of IECs and gut epithelium.

Results: TsSP1.1 was a surface and secretory protein, which was expressed at various T. spiralis stages, and principally localized at cuticle, stichosome and embryos of the nematode. rTsSP1.1 accelerated larval intrusion of IECs, whereas anti-rTsSP1.1 antibodies impeded larval intrusion. The acceleration and inhibtion was dose-dependently related to rTsSP1.1 and anti-TsSP1.1 antibodies. Block of the IIL with anti-rTsSP1.1 serum also impeded larval intrusion of gut mucosa.

Conclusion: TsSP1.1 participates in T. spiralis intrusion of gut epithelium.

1. Pozio E. World distribution of Trichinella spp. Infections in animals and humans. Vet Parasitol. 2007;149:3-21.
2. Cui J, Jiang P, Liu LN, et al. Survey of Trichinella infections in domestic pigs from northern and eastern Henan, China. Vet Parasitol. 2013;194(2-4):133-5.
3. Liu RD, Cui J, Liu XL, et al. Comparative proteomic analysis of surface proteins of Trichinella spiralis muscle larvae and intestinal infective larvae. Acta Trop. 2015;150:79-86.
4. Wang ZQ, Li LZ, Jiang P, Liu LN, Cui J. Molecular identification and phylogenetic analysis of Trichinella isolates from different provinces in mainland china. Parasitol Res. 2012;110:753-757.
5. Jiang P, Wang ZQ, Cui J, Zhang X. Comparison of artificial digestion and baermann's methods for detection of Trichinella spiralis pre-encapsulated larvae in muscles with low-level infections. Foodborne Pathog Dis. 2012;9:27-31.
6. Song YY, Zhang Y, Yang DQ, et al. The immune protection induced by a serine protease inhibitor from the foodborne parasite Trichinella spiralis. Fron Microbiol. 2018;9:1544.
7. Liu LN, Cui J, Zhang X, Wei T, Jiang P, Wang ZQ. Analysis of structures, functions, and epitopes of cysteine protease from Spirometra erinaceieuropaei spargana. Biomed Res Int. 2013;2013
8. Sun GG, Song YY, Jiang P, et al. Characterization of a Trichinella spiralis putative serine protease. Study of its potential as sero-diagnostic tool. Plos Neg Trop Dis. 2018; 12(5):e0006485.
9. Zhang XZ, Sun XY, Bai Y, et al. Protective immunity in mice vaccinated with a novel elastase-1 significantly decreases Trichinella spiralis fecundity and infection. Vet Res. 2020;51
10. Cui J, Ren HJ, Liu RD, Wang L, Zhang ZF, Wang ZQ. Phage-displayed specific polypeptide antigens induce significant protective immunity against Trichinella spiralis infection in balb/c mice. Vaccine. 2013;31:1171-1177.
11. Hu CX, Zeng J, Hao HN, et al. Biological properties and roles of a Trichinella spiralis inorganic pyrophosphatase in molting and developmental process of intestinal larval stages. Vet Res. 2021; 52(1):6.
12. ManWarren T, Gagliardo L, Geyer J, McVay C, Pearce-Kelling S, Appleton J. Invasion of intestinal epithelia in vitro by the parasitic nematode Trichinella spiralis. Infect Immun. 1997;65:4806-4812.
13. Yang DQ, Zeng J, Sun XY, et al. Trichinella spiralis: Rnai-mediated silencing of serine protease results in reduction of intrusion, development and fecundity. Trop Biomed. 2020;37:932-946.
14. Liu RD, Cui J, Wang L, Long SR, Zhang X, Liu MY, Wang ZQ. Identification of surface proteins of Trichinella spiralis muscle larvae using immunoproteomics. Trop Biomed. 2014;31:579-591.
15. Li CY, Bai X, Liu XL, et al. Disruption of epithelial barrier of caco-2 cell monolayers by excretory secretory products of Trichinella spiralis might be related to serine protease. Front Microbiol. 2021;12: 634185.
Files
IssueVol 17 No 3 (2022) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijpa.v17i3.10628
Keywords
Trichinella spiralis Serine protease 1.1 Intrusion Intestinal epithelium

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
How to Cite
1.
Liu F, Song YY, Zhang R, Liu RD, Jiang P, Cui J, Wang ZQ. Cloning and Expression of a New Trichinella spiralis Serine Protease and Its Role in Invading Host Intestinal Epithelium. Iran J Parasitol. 2022;17(3):375-384.