Evaluation of Recombinant GRA2 Protein in Diagnosis of Toxoplasma gondii Infection by ELISA

Backgrounds & Dense granule antigen(GRA) of Toxoplasma gondii parasite is important in survival and pathogenicity of Toxoplasmosis. GRA2 is one of the dense granule proteins that can be useful specifically in detection of antibodies against toxoplasm antigens and diagnosis of infection.The aim of this survey was to evaluate recombinant GRA2 protein in diagnosis of toxoplasmosis by ELISA. The recombinant GRA2 protein was produced by culturing of Escherichia coli (BL21(DE3)pLysS) and purified by affinity chromatography. GRA2 was then used as antigen in ELISA Plate for evaluation of serum diagnosis ability which was previously identified as a standard method in both acute and chronic phases. In this study, 35 acute and 40 chronic phase sera were distinctly investigated, using the plates coated by recombinant GRA2 protein. All of 35 acute phase sera (100%) and 31 (77.5%) out of 40 chronic phases reacted with recombinant GRA2 antigen. The results showed that they were all over cut off point or line. The recombinant GRA2 protein may improve diagnosis process with a higher accuracy specificity compared with whole antigen. It may be also considered for standardization improvment in diagnosis techniques for Toxoplasma gondii.