Cystic Echinococcosis is a parasitic disease with cosmopolitan distribution caused by the tape worm Echinococcus granulosus. Fibrous layer is developed around the cyst as a host immune response reaction. The aim of this study was to evaluate the rate of IL-4 gene expression in fibrous layer of bovine and ovine hepatic hydatid cysts using quantitative technique of Real-Time PCR. In this descriptive study the samples of hydatid cyst fibrous layer were taken from 6 bovine and 6 ovine hepatic hydatid cysts. Samples of normal liver tissue close to the cyst were also taken as controls. Total RNA from each sample was extracted and then converted to cDNA. Afterward, the rate of IL-4 gene expression for each sample was evaluated using real-time PCR technique. Data were analyzed by REST software (version 2.0.13, 2009). In sheep the rate of IL-4 gene expression in the fibrous layer of hepatic hydatid cysts was 1.98 times more than the rate of IL4 gene expression in control samples, but the difference was not significant (P = 0.561). In cattle the rate of IL-4 gene expression in the fibrous layer of hepatic hydatid cysts was 9.84 times more than that of control samples which was statistically significant (P < 0.001). With high rate of IL4 expression especially in fibrous layer of bovine hydatid cyst, it can be concluded that this interleukin may play an important role in host parasite relationship.
Keywords: Fibrous layer; Gene expression; Hydatid cyst; IL-4; Real-Time PCR.