Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 5 2 2010 06 15 1 9 EN N Jalallou Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University, M.C., Tehran, Iran M Bandepour Cellular and Molecular Biology Research Centers, Shahid Beheshti University, M.C., Tehran, Iran H Khazan Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University, M.C., Tehran, Iran A Haghighi Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University, M.C., Tehran, Iran SH Abdollahi Dept. of Medical Microbiology, School of Medicine, Rafsanjan University, Rafsanjan, Iran B Kazemi Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University, M.C., Tehran, Iran AND Cellular and Molecular Biology Research Centers, Shahid Beheshti University, M.C., Tehran, Iran 2015 10 03 Background: Although some serological tests for the detection of Toxoplasma gondii-specific immunoglobulin are commercially available, better diagnostic tools are needed. The aim of pre­sent study was to evaluate the usefulness of the recombinant Toxoplasma gondii SAG1 antigen for the recognition of toxoplasmosis by ELISA. Methods: This study was conducted in Cellular and Molecular Biology Research Centers, Sha­hid Beheshti University, M.C., Tehran, Iran in 2008-2009. Surface antigen 1 (SAG1), a tachy­zoite stage-specific protein, was subcloned into an expression vector and was subsequently trans­formed into BL21 (DE3) pLysS competent bacterial cells. After inducing expression of the recombi­nant antigen, the protein product was purified using Ni-affinity chromatography. The immuno­reactivity of recombinant SAG1 (rSAG1) was analyzed by SDS-PAGE and western blot­ting. The reactivity of the rec-SAG1 protein was evaluated using an ELISA. Result: Sensitivity and specificity of the generated recombinant-ELISA (rec-ELISA) compared to a commercially available ELISA (com-ELISA) were 88.4% and 88%, respectively. Conclusion: Recombinant SAG1 produced in E. coli is a promising antigen that can be used in diag­nostic assays for the detection of specific antibodies against T. gondii. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/129 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/129/128