Korean J Parasitol.  2011 Sep;49(3):207-212. 10.3347/kjp.2011.49.3.207.

Development and Clinical Evaluation of a Rapid Serodiagnostic Test for Toxoplasmosis of Cats Using Recombinant SAG1 Antigen

• Chong CK
• Jeong W
• Kim HY
• An DJ
• Jeoung HY
• Ryu JE
• Ko AR
• Kim YJ
• Hong SJ
• Yang Z
• Nam HW

• KMID: 1715642
• DOI: http://doi.org/10.3347/kjp.2011.49.3.207

Abstract

Rapid serodiagnostic methods for Toxoplasma gondii infection in cats are urgently needed for effective control of transmission routes toward human infections. In this work, 4 recombinant T. gondii antigens (SAG1, SAG2, GRA3, and GRA6) were produced and tested for the development of rapid diagnostic test (RDT). The proteins were expressed in Escherichia coli, affinity-purified, and applied onto the nitrocellulose membrane of the test strip. The recombinant SAG1 (rSAG1) showed the strongest antigenic activity and highest specificity among them. We also performed clinical evaluation of the rSAG1-loaded RDT in 182 cat sera (55 household and 127 stray cats). The kit showed 0.88 of kappa value comparing with a commercialized ELISA kit, which indicated a significant correlation between rSAG1-loaded RDT and the ELISA kit. The overall sensitivity and specificity of the RDT were 100% (23/23) and 99.4% (158/159), respectively. The rSAG1-loaded RDT is rapid, easy to use, and highly accurate. Thus, it would be a suitable diagnostic tool for rapid detection of antibodies in T. gondii-infected cats under field conditions.

Keyword

Toxoplasma gondii; cat; rapid diagnostic test; serodiagnosis; recombinant SAG1

MeSH Terms

Animals
Antigens, Protozoan/*diagnostic use/genetics
Cat Diseases/*diagnosis
Cats
Chromatography, Affinity
Escherichia coli/genetics
*Point-of-Care Systems
Protozoan Proteins/*diagnostic use/genetics
Recombinant Proteins/diagnostic use/genetics
Sensitivity and Specificity
Serologic Tests/methods
Toxoplasma/genetics
Toxoplasmosis, Animal/*diagnosis
Veterinary Medicine/*methods