Korean J Parasitol.  2016 Feb;54(1):21-29. 10.3347/kjp.2016.54.1.21.

A Novel Polyclonal Antiserum against Toxoplasma gondii Sodium Hydrogen Exchanger 1

• Xiao B
• Kuang Z
• Zhan Y
• Chen D
• Gao Y
• Li M
• Luo S
• Hao W

• KMID: 2374013
• DOI: http://doi.org/10.3347/kjp.2016.54.1.21

Abstract

The sodium hydrogen exchanger 1 (NHE1), which functions in maintaining the ratio of Na+ and H+ ions, is widely distributed in cell plasma membranes. It plays a prominent role in pH balancing, cell proliferation, differentiation, adhesion, and migration. However, its exact subcellular location and biological functions in Toxoplasma gondii are largely unclear. In this study, we cloned the C-terminal sequence of T. gondii NHE1 (TgNHE1) incorporating the C-terminal peptide of NHE1 (C-NHE1) into the pGEX4T-1 expression plasmid. The peptide sequence was predicted to have good antigenicity based on the information obtained from an immune epitope database. After induction of heterologous gene expression with isopropyl-b-D-thiogalactoside, the recombinant C-NHE1 protein successfully expressed in a soluble form was purified by glutathione sepharose beads as an immunogen for production of a rabbit polyclonal antiserum. The specificity of this antiserum was confirmed by western blotting and immunofluorescence. The antiserum could reduce T. gondii invasion into host cells, indicated by the decreased TgNHE1 expression in T. gondii parasites that were pre-incubated with antiserum in the process of cell entry. Furthermore, the antiserum reduced the virulence of T. gondii parasites to host cells in vitro, possibly by blocking the release of Ca2+. In this regard, this antiserum has potential to be a valuable tool for further studies of TgNHE1.

Keyword

Toxoplasma gondii; soluble expression; TgNHE1; polyclonal antiserum; Ca2+ release

MeSH Terms

Animals
Cell Line
Immune Sera/genetics/immunology/*metabolism
Male
Mice
Protozoan Proteins/genetics/*metabolism
Rabbits
Recombinant Proteins/immunology
Sheep
Sodium-Hydrogen Antiporter/genetics/immunology/*metabolism
Toxoplasma/genetics/immunology/*metabolism
Toxoplasmosis/parasitology/prevention & control
Immune Sera
Protozoan Proteins
Recombinant Proteins
Sodium-Hydrogen Antiporter