Isoenzyme and Molecular Characterization of Larval Stage of the Echinococcus granulosus sensu lato Based on the Host Variation in Iran

Abstract

Background: Simultaneous isoenzyme and molecular characterization of Echinococcus granulosus sensu lato have not been investigated in Iran. The present study aims to investigate the isoenzyme pattern of the larval stage of Echinococcus spp. genotypes based on their host types in Iran.Methods and Results: A total of 32 samples, including 8 human and 24 animal hydatid cyst isolates, were collected from May 2018 to December 2020. The protoscolices were removed from the cyst, and their genotypes were determined by the molecular method followed by isoenzyme electrophoresis. The activities of five enzymatic systems including glucose 6-phosphate dehydrogenase (G6PD), malate dehydrogenase (MDH), malic enzyme (ME), nucleoside hydrolyse 1 (NH1) and isocitrate dehydrogenase (ICD) were evaluated. Sequence analysis of the samples showed the specimens as E. granulosus sensu stricto (G1) 24 (75%), and E. canadensis (G6) 8 (25%) genotypes. The isoenzyme pattern of ICD of both the strains produced a six-band pattern, with different Relative Factors (RF). The G6PD produces two bands with different relative migration in both genotypes. The MDH and NH1 systems revealed two-band pattern in the E. granulosus sensu stricto strain, while it produced only one band in the ME enzyme. Furthermore, in the E. canadensis strain the MDH and NH1 enzymes showed one band and the ME enzyme represented a two-band pattern.Conclusion: The finding of the present study revealed that the entirely different isoenzyme patterns in the systems of NH1, G6PD, MDH and ME may be used for differentiation of E. granulosus sensu stricto and E. canadensis strains.