Mohammad Talebzadeh, Reyhaneh Mohabati, Jalal Babaie, Samira Amiri, Mojgan Allahyari, Majid Golkar,
Volume 2, Issue 1 (1-2014)
Abstract
Introduction : Toxoplasmosis is a parasitic infection caused by the protozoan Toxoplasma gondii it leads to serious medical problems in congenitally-infected and immunocompromised individuals, while it is quite harmless in immunocompetent individuals. Toxoplasma tissue cyst matrix protein (MAG1) induces early humoral and cell-mediated immune responses. Previous studies suggested recombinant MAG1 as a promising antigen for serodiagnosis of Toxoplasma infection. A DNA fragment encoding mag1, comprising amino acids 50 to 207, was amplified from T . gondii RH strain and cloned in prokaryotic expression plasmid pET-15b(+). The cloned DNA fragment was sequenced and showed 100% similarity with the published sequences available in GenBank Database. Recombinant MAG1 was expressed in Escherichia coli, and was highly purified in a single step by immobilized metal ion affinity chromatography. In Western blot analysis, purified protein showed a much stronger reactivity with sera from patients with acute Toxoplasma infection, compared to those with chronic infection. MAG1 protein, in combination with other acute-phase markers might be useful in discriminating acute/reactivated Toxoplasma infections from chronic forms. J Med Microbiol Infec Dis, 2014, 1 (2): 5 pages.
Saied Reza Naddaf, Reyhaneh Mohabati, Rouhollah Vahabpor, Sabah Naeimi, Sana Eybpoosh,
Volume 8, Issue 3 (7-2020)
Abstract
Introduction: Leptospirosis is a significant public health problem in the Caspian littoral of Iran comprising Gilan, Mazandaran, and Golestan provinces. In Golestan province, serology assays indicated anti-Leptospira antibodies in animals and humans; however, no reliable record of infections in patients with signs and symptoms of the disease is available. Methods: We employed the indirect immunofluorescent antibody assay (IFA), and two PCR assays, a real-time PCR (qPCR) and a nested-PCR targeting 16S rDNA (rrs) sequence for diagnosis of leptospirosis in febrile patients in Golestan province. Results: Out of 52 febrile patients, 25 (48.07%) had antibody titers ≥1/80 by IFA, and were defined as positive. In 7, 9, and 7 individuals, the antibody titers were 1/40, 1/20, and 1/10, respectively, and 4 had no antibodies. The qPCR and nested PCR detected leptospiral DNA in 55.75% and 67.3% of the patients' sera, respectively. The two PCR assays had a Kappa agreement of 0.53 (P< 0.0001), suggesting a moderate agreement, and showed a significant reverse association with the IFA titers (P<0.05). Conclusion: Our results suggest that higher antibody titers accompanied the spirochete's removal from blood by the patient's immune response. Hence, a reliable diagnosis of Leptospira infection necessitates deploying a DNA-based method alongside serology.
