Korean J Parasitol.  2013 Oct;51(5):503-510.

A Rapid Diagnostic Test for Toxoplasmosis using Recombinant Antigenic N-terminal Half of SAG1 Linked with Intrinsically Unstructured Domain of GRA2 Protein

• Song KJ
• Yang Z
• Chong CK
• Kim JS
• Lee KC
• Kim TS
• Nam HW

Abstract

Toxoplasma gondii is an apicomplexan parasite with a broad host range of most warm-blooded mammals including humans, of which one-thirds of the human population has been infected worldwide which can cause congenital defects, abortion, and neonatal complications. Here, we developed a rapid diagnostic test (RDT) for T. gondii infection. Antigenic N-terminal half of the major surface antigen (SAG1) was linked with intrinsically unstructured domain (IUD) of dense granule protein 2 (GRA2). The recombinant GST-GRA2-SAG1A protein was successfully expressed and purified as 51 kDa of molecular weight. Furthermore, antigenicity and solubility of the rGST-GRA2-SAG1A protein were significantly increased. The overall specificity and sensitivity of GST-GRA2-SAG1A loaded RDT (TgRDT) were estimated as 100% and 97.1% by comparing with ELISA result which uses T. gondii whole cell lysates as the antigen. The TgRDT tested with Uganda people sera for field trial and showed 31.9% of seroprevalence against T. gondii antibody. The TgRDT is proved to be a kit for rapid and easy to use with high accuracy, which would be a suitable serodiagnostic tool for toxoplasmosis.

Keyword

Toxoplasma gondii; serodiagnosis; rapid diagnostic test; recombinant GST-GRA2-SAG1A; ELISA; intrinsically unstructured domain

MeSH Terms

Adolescent
Adult
Amino Acid Sequence
Antibodies, Protozoan/*blood
Antigens, Protozoan/genetics/*immunology
Child
Child, Preschool
Female
Humans
Infant
Male
Molecular Sequence Data
Protozoan Proteins/genetics/*immunology
Recombinant Fusion Proteins
Reproducibility of Results
Republic of Korea/epidemiology
Sensitivity and Specificity
Serologic Tests
Time Factors
Toxoplasma/genetics/*immunology/isolation & purification
Toxoplasmosis/*diagnosis/epidemiology/parasitology
Uganda/epidemiology
Young Adult
Antibodies, Protozoan
Antigens, Protozoan
Protozoan Proteins
Recombinant Fusion Proteins