Preparation of monoclonal antibodies against gamma-type phospholipase A(2) inhibitors and immunodetection of these proteins in snake blood

BACKGROUND: The gamma-type phospholipase A(2) inhibitor (PLIγ) is a natural protein commonly found in snake serum, which can neutralize pathophysiological effects of snake venom phospholipases A(2). Therefore, this protein is a potential candidate to the development of a novel antivenom. To the best of our knowledge, there is no antibody currently available for PLIγ identification and characterization. METHODS: Bioinformatics prediction of epitope using DNAStar software was performed based on the sequence of Sinonatrix annularis PLIγ (SaPLIγ). The best epitope (151)CPVLRLSNRTHEANRNDLIKVA(172) was chosen and synthesized, and then conjugated to keyhole limpet hemocyanin and bovine serum albumin for use as an immunogen and plate-coating antigen, respectively. RESULTS: Eighteen IgG anti-PLIγ mAb hybridoma cell strains were obtained, and all the mAbs had positive interaction with recombinant His6-PLIγ and natural SaPLIγ. Moreover, the mAb from 10E9 strain was also successfully used for the immunodetection of other snake serum PLIγs. cDNA sequence alignment of those PLIγs from different snake species showed that their epitope segments were highly homologous. CONCLUSIONS: The successful preparation of anti-PLIγmAb is significant for further investigation on the relationship between the structure and function of PLIγs, as well as the interaction between PLIγs and PLA(2)s.