Hamid Reza Rahimi; Tahereh Mohammadzadeh; Seyed Mahmoud Sadjjadi; Bahador Sarkari; Farzaneh Zahabiun
Volume 14, Issue 2 , June 2017, , Pages 123-133
Abstract
Background: Echinococcosis is a zoonotic parasitic disease caused by the larval stage of Echinococcus granulosus. Several native and recombinant antigens, derived from different stages of E. granulosus life cycle, have been used for vaccine trials. In vitro reared adult worms are good candidates for ...
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Background: Echinococcosis is a zoonotic parasitic disease caused by the larval stage of Echinococcus granulosus. Several native and recombinant antigens, derived from different stages of E. granulosus life cycle, have been used for vaccine trials. In vitro reared adult worms are good candidates for vaccination as they do not produce fertile egg/s and do not have any risk of contamination for researchers. Objective: To evaluate different antigens derived from in vitro reared E. granulosus adult worms for the immunization of BALB/c mice against secondary hydatidosis. Methods: Viable protoscoleces (PCSs) of sheep hydatid cyst were cultivated in S.10E.H media. Excretory secretory (E/S) and crude antigens were prepared from reared adult worms. A total of fifty BALB/c mice, each 8-weeks-old, were divided into 5 groups of 10 mice. Three groups were subcutaneously immunized with crude, E/S and immunodominant antigens on days 1 and 28. The fourth group received only PBS and the fifth group had no injection. Three weeks following the second immunization, all groups were challenged, intraperitoneal, with viable PSCs. After the autopsy of the mice and opening their abdominal wall, cysts were counted and measured followed by histopathological observations. Results: The highest protective immunity (98.7%) against hydatidosis was induced by crude antigen, followed by E/S and immunodominant antigens. Conclusion: Antigens (crude antigens in particular) derived from in vitro reared E. granulosus adult worms, and their different protein components are suitable candidates for the vaccination of intermediate hosts against hydatidosis.
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.