Zahra Rezaei; Gholamreza Pouladfar; Amin Ramezani; Zohreh Mostafavi-Pour; Amin Abbasian; Bahador Sarkari; Bahman Pourabbas
Abstract
Background: Visceral leishmaniasis (VL) can lead to death in more than 95% of cases if left untreated. Accurate and early diagnosis has an important role in reducing mortality rate of this disease. Objective: To express recombinant H2B antigen from an Iranian isolate of Leishmania Infantum and evaluate ...
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Background: Visceral leishmaniasis (VL) can lead to death in more than 95% of cases if left untreated. Accurate and early diagnosis has an important role in reducing mortality rate of this disease. Objective: To express recombinant H2B antigen from an Iranian isolate of Leishmania Infantum and evaluate its efficacy in the diagnosis of VL. Methods: The recombinant H2B antigen was produced in a prokaryotic system, and its efficacy for VL diagnosis was evaluated by ELISA. The serum samples from 80 VL patients, 100 individuals from endemic and non-endemic regions of VL, and 58 non-VL patients were collected. VL cases were confirmed based on the clinical sign, positive IFAT (>64), real time PCR, and response to treatment. Results: The H2B gene sequence of the Iranian L. infantum isolate had about 4% diversity in comparison with the H2B gene of the L. infantum counterpart. ELISA, using the produced H2B recombinant antigen, showed sensitivity of 71.25% (95% CI: 60.05%-80.82%) and specificity of 69.62% (95% CI: 61.81%-76.68%) regarding VL diagnosis. Conclusion: Recombinant H2B antigen expressed in the prokaryotic system had suboptimal performance for the serological diagnosis of VL. It seems that the production and expression of recombinant H2B antigen in a eukaryotic system may enhance the performance of this antigen in the diagnosis of VL in Iran.
Shamsi Noorpisheh Ghadimi; Shirin Farjadian; Gholam Reza Hatam; Mehdi Kalani; Bahador Sarkari
Abstract
Background: Toll like receptors play a major role in immune responses against Leishmania parasites. Objective: To evaluate the efficacy of vaccination with live attenuated L. major and TLR4 agonist in protection against L. major infection. Methods: Attenuated L. major was prepared by continuous sub-culturing ...
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Background: Toll like receptors play a major role in immune responses against Leishmania parasites. Objective: To evaluate the efficacy of vaccination with live attenuated L. major and TLR4 agonist in protection against L. major infection. Methods: Attenuated L. major was prepared by continuous sub-culturing of the parasite. A total of 90 mice were assigned to 9 groups including 6 groups of BALB/c (G1-6) and 3 groups (G7-9) of C57BL/6 mice. Group 1 was the control groups, group 2 received the wild-type L. major promastigotes, group 3 the attenuated line, group 4 the TLR4 agonist, group 5 the wild-type L. major and TLR4 agonist, and group 6 the attenuated line along with TLR4 agonist. Group 7 was control, group 8 received wild-type L. major and group 9 the wild-type along with TLR4 agonist. Vaccinated mice were then challenged with wild-type of L. major. Lesion size, parasite burden, and the expression levels of IL-4, IFN-γ, IL-2, 1L-17A, IL-10, TGF-β and TLR4 were evaluated before the challenge while parasite burden and lesion size were evaluated. Results: Vaccinated mice with a TLR4 agonist or attenuated L. major plus TLR4 agonist produced the highest levels of IFN-γ, IL-2, and IL-17A. Post-challenge analysis revealed that mice vaccinated with the attenuated line along with TLR4 agonist displayed the lowest lesion size and parasite load. These mice developed a predominant Th1 immune response. Conclusion: Vaccination with the attenuated L. major along with TLR4 agonist promotes a Th1-mediated immune response which leads to the protection of BALB/c mice against L. major infection.
Mohammad Amin Ghatei; Gholamreza Hatam; Seyed Mohammad Hossein Hosseini; Bahador Sarkari
Volume 6, Issue 4 , December 2009, , Pages 202-207
Abstract
Background: Visceral leishmaniasis (VL) is an endemic disease in some parts of Iran. Many techniques have been used for diagnosis of VL, among which the urine based la-tex agglutination test (KAtex) is a promising one. Objective: To compare three diag-nostic tests of VL including KAtex, ELISA and Direct ...
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Background: Visceral leishmaniasis (VL) is an endemic disease in some parts of Iran. Many techniques have been used for diagnosis of VL, among which the urine based la-tex agglutination test (KAtex) is a promising one. Objective: To compare three diag-nostic tests of VL including KAtex, ELISA and Direct Agglutination Test (DAT) in VL patients and healthy controls in the south west of Iran. Methods: Serum (n = 29) and urine samples (n = 31) were collected from parasitologically confirmed VL patients. Control samples were obtained from healthy individuals (n = 61) and also from patients with infectious diseases other than VL. The collected serum samples were tested by DAT and ELISA using crude antigen from promastigotes of Leishmania infantum and the urine samples were tested by KAtex. Results: Sensitivity and specificity of KAtex for diagnosis of VL was found to be 83.9% and 100%, respectively. Sensitivities of DAT and ELISA were 93.1% and 86.2% and their specificities were 100% and 90.5%, respectively. Conclusion: KAtex yielded a satisfactory sensitivity and specificity in di-agnosis of VL in Iran and can be recommended as a rapid, field applicable and reliable test for diagnosis of VL in this region.
Seyed Mahmoud Sadjjadi; Hassan Abidi; Bahador Sarkari; Ahmad Izadpanah; Sakineh Kazemian
Volume 4, Issue 3 , December 2007, , Pages 167-172
Abstract
Background: Hydatidosis is one of the cosmopolitan parasitic zoonoses caused by the larval stage of Echinococcus granulosus. Diagnosis of hydatidosis is still an unresolved problem. Serological tests using crude antigens for diagnosis of E. granulosus are sensi-tive, however their specificity are not ...
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Background: Hydatidosis is one of the cosmopolitan parasitic zoonoses caused by the larval stage of Echinococcus granulosus. Diagnosis of hydatidosis is still an unresolved problem. Serological tests using crude antigens for diagnosis of E. granulosus are sensi-tive, however their specificity are not satisfactory. Therefore, WHO recommended spe-cific serological methods using specific antigens, specially native AgB for proper diagno-sis. Objectives: This study was designed to evaluate the ELISA and counter current im-munoelectrophresis (CCIEP) method using native antigen B (Ag B) for serodiagnosis of human hydatidosis in Fars Province, Iran, an endemic area for this parasitic disease. Methods: Native AgB was purified from sheep hydatid fluid. Serum samples obtained from 40 pathologically confirmed cases of hydatidosis along with samples from patients with fascioliasis, toxocariasis, taeniasis and cancer patients and sera from healthy indi-viduals were tested by ELISA using native antigen B or tested by countercurrent immu-noelectrophresis (CCIEP) using crude sheep hydatid cyst fluid. Results: Sensitivity of the ELISA system was determined to be 92.5% and the specificity was found to be 97.3%. Positive and negative predictive values of the system were 92.5% and 97.3%, respec-tively. For countercurrent immunoelectrophresis the sensitivity of the assay was 97.5% and its specificity was 58.18%. This ELISA system is much more specific in detecting anti hydatid cyst antibody than CCIEP, while CCIEP is more sensitive in detecting anti hydatid cyst antibody. Conclusion: The new ELISA system using native antigen B is a suitable method and preferable to CCIEP for immunodiagnosis of human hydatidosis.
Fattaneh Mikaeili; Mahdi Fakhar; Bahador Sarkari; Mohammad H. Motazedian; Gholamreza Hatam
Volume 4, Issue 2 , June 2007, , Pages 116-121
Abstract
Background: The causative agent of visceral leishmaniasis (VL) in Iran is Leishmania infantum (L. infantum) (Mediterranean type) and its major reservoir host is the dog. Ob-jective: To compare the serological methods including direct agglutination test (DAT), indirect immunofluorescent-antibody test ...
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Background: The causative agent of visceral leishmaniasis (VL) in Iran is Leishmania infantum (L. infantum) (Mediterranean type) and its major reservoir host is the dog. Ob-jective: To compare the serological methods including direct agglutination test (DAT), indirect immunofluorescent-antibody test (IFA) and enzyme-linked immunosorbent as-say (ELISA) for serodiagnosis of endemic strain of L. infantum. Methods: 61 blood samples from VL patients referred to Shiraz hospitals and 49 blood samples from con-trol group were collected. Native strain of the parasite isolated from a VL patient from the region was cultured and characterized. Antigens from this L. infantum parasite were used in ELISA and IFA system. Results: Anti-Leishmania antibody was detected in 43 (70.5%), 49 (80.3%) and 51(83.6%) cases using DAT, IFA and ELISA, respectively. Based on these results, sensitivity and specificity of DAT was found to be 70.5% and 100%, respectively. Sensitivities of IFA and ELISA in diagnosis of VL were 80.3% and 83.6% and their specificity was 90.5%. Conclusion: Results of this study showed that DAT and ELISA have the highest specificity and sensitivity in diagnosis of VL. DAT is a simple, cost-effective and field applicable test. Thus, it can be recommended for early and accurate diagnosis of VL, especially in regions where malaria, brucellosis and tu-berculosis are prevalent.
