TY - JOUR ID - 117490 TI - Development of a Lateral Flow Immunoassay Using Recombinant Dense Granular Antigen (GRA) 7 to Detect Anti-Toxoplasma gondii IgG Antibodies JO - Archives of Razi Institute JA - ARI LA - en SN - 0365-3439 AU - Morovati, H. AU - Seyyed Tabaei, S. J. AU - Gholamzad, M. AU - Omidfar, K. AU - Ahmadi, A. AU - Arab Mazar, Z. AU - Eshaghi, A. AU - Sheikhsofla, F. AD - Department of Parasitology and Mycology, Faculty Medicin, Shahid Beheshti University of Medical Sciences, Tehran, Iran AD - Department of Microbiology and Immunology, Islamic Azad University, Tehran Medical Branch, Tehran, Iran AD - Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran AD - Infectious Diseases and Tropical Medicine Research Center, Shahid Beheshti University of Medial Sciences, Tehran, Iran AD - Department of Quality Control, Razi Vaccine and Serum Research Institute, Agricultural Research Education and Extension Organization, Karaj, Iran AD - Department of Technical and Research Lab, Arvin Pazhoohan Noor (APN), Tehran, Iran Y1 - 2019 PY - 2019 VL - 74 IS - 1 SP - 39 EP - 49 KW - Toxoplasma gondii KW - rGRA7 KW - Rosetta (DE3) KW - pET-32a(+) KW - lateral flow immunoassay (LFA) DO - 10.22092/ari.2018.115890.1155 N2 - Toxoplasma gondii is an intracellular protozoan parasite that causes toxoplasmosis and is of medical importance in pregnant women and immunosuppressed patients. In recent years, many methods have been developed for the detection of infection caused by this parasite; however, most of the developed methods are not adequately sensitive. The dense granular antigen (GRA) 7 is a highly immunogenic protein that is used as a specific antigen for the diagnosis of toxoplasmosis. This study was designed to produce recombinant GRA7 (rGRA7) antigen in bacterial system in order to be applied as an antigen for developing a simple and rapid lateral flow immunoassay test strip using a gold nanoparticle-pAb conjugate probe to detect Toxoplasma IgG-specific antibodies in human sera. After the extraction of genomic DNA from RH strain tachyzoites, polymerase chain reaction (PCR) was performed using specific primers considering restriction sites and BglII and XhoI enzymes. Subsequently, the GRA7 gene was cloned in pET-32a (+) expression vector, and then pET-32a(+)-GRA7 was transformed into E. coli Rosetta (DE3). The induction of protein production was accomplished by IPTG, and the product was finally purified by Ni-NTA affinity chromatography. In order to make the strip test, the anti-human gold nanoparticle conjugate was applied on conjugate pad, rGRA7 antigen was immobilized to a nitrocellulose membrane as the capture agent, and sample and absorbance pads were assembled on a backing card. For the analysis of the sensitivity and specificity of the assay, the selected patients’ sera samples were tested by standard chemiluminescence immunoassay (CLIA) method, and then compared with TOXO-IgG strip results. The findings showed that the use of rGRA7 is an accurate, sensitive, and inexpensive technique for the rapid detection of anti-Toxo­plasma IgG in human sera. Therefore, rGRA7 can be applied as a diagnostic agent in laboratories. UR - https://archrazi.areeo.ac.ir/article_117490.html L1 - https://archrazi.areeo.ac.ir/article_117490_c98b14139a8034e4b2c7f9ad0ed6f7cd.pdf ER -