Background and aims: Hydatid cyst is the larval stage of the tape worm Echinococcu granulosus. Anticancer effects of some parasites have been shown. Moreover, existence of common antigens between some parasites especially hydatid cyst and cancers have been reported. So, immunological cross reaction between hydatid cyst and cancer cell antigens has been investigated in this study. Methods: In this laboratory descriptive study, different hydatid cyst antigens were prepared and antibody raised against them in rabbits. In dot immunoblotting, those antigens were probed with sera of patients with cancers (collected from Imam Hossein Hospital in Isfahan). Also, cross reaction among excretory secretory products of cancer cells and antisera raised against different hydatid cyst antigen was investigated. In order to remove carbohydrate bands of antigens, sodium periodate buffer was used. Results: Antisera raised against laminated & germinal layers of hydatid cyst reacted with excretory secretory products of cancer cells. Also, antigens of hydatid cysts reacted with cancer patients sera. Carbohydrate bands of antigens were involved in some immunological cross reactions. Conclusion: Results of this work emphasis existence of common antigens between hydatid cyst and cancers. Therefore, more study about these common antigens is recommende
