Identification and purification of a specific and immunogenic antigen of the laminated layer of the hydatid cyst and production of an antigen-specific monoclonal antibody.

Cystic echinococcosis (CE) is an infection caused by the larval stage of Echinococcus granulosus. This is widely distributed through Iran, where a variety of animals act as intermediate host. The immunogenic antigens (Ag) of different compartments of the hydatid cyst have been already determined. One of these compartments is the laminated layer (LL). We have extracted a protein with the MW of 24 kDa from a lysate prepared from the LL and produced a monoclonal antibody (mAb) against this protein. Five mAb named P3F6s, P2H4s, P1A6s, P1C3s, and P1F7s have been produced. The isotype analysis showed that P3F6s is IgG1 and the rest are IgM. P3F6s was purified from the ascitic fluid of mice injected with P3F6s hybridoma intraperitoneally. Western blot and ELISA analysis showed that this mAb could recognize the purified 24 kDa prepared from lysate of LL. Since a 24 kDa protein has been shown to be an immunogenic Ag, this protein can be used as a candidate for the development of diagnostic tests and vaccine strategies. For these aims, P3F6s can be used for the purification of this 24 kDa protein.