Abstract:

Objective To prepare and identify the monoclonal antibodies (mAb) against Giardia lamblia.Methods Two BALB/c mice of 8 weeks were immunized with antigens extracted from G. lamblia trophozoites, based on which mAb was prepared with traditional hybridoma technology. mAb isotyping was performed using enzyme-linked immunosorbent assay (ELISA) with coatings by soluble trophozoites antigen (STA) and excretory-secretory protein (ESP) prepared from G. lamblia trophozoites. mAb recognition of STA and ESP was identified by Western blotting. ELISA was performed to detect mAb reactions with G. lamblia trophozoite antigen as well as its cross-reactions with antigens from other parasite species. Results Twelve mAb-secreting hybridoma cell lines were obtained, comprising BB3, CE5, CC10, EG4, GC7, CC1, EF6, DB8, BG10, GH7, HC7 and EB2, all producing the IgG1-subtype mAb. The EB2 mAb specifically recognized proteins with M_r of 175 000 and 191 000 from STA and ESP, respectively, with no cross-reactions to the antigen extracts from Escherichia coli, Ascaris suum, Blastocystis hominis, eggs and adult worms of Schistosoma japonicum, and adult worms of Paragonimus westermani. Conclusion The specific IgG1-type mAb for G. lamblia trophozoites has been prepared.

Key words: Giardia lamblia, Trophozoite, Monoclonal antibody, ELISA, Western blotting