Objective: To prepare and characterize rabbit polyclonal antibodies against Toxoplasma gondii vacuolar proton pyrophosphatase type I (TgVP1).
Methods and results: Two synthesized peptides TgVP1-1 and TgVP1-2 as the haptens were conjugated with KLH to immunize rabbits. Indirect ELISA showed that the titers of rabbit anti-TgVP1-1 polyclonal antibody and rabbit anti-TgVP1-2 polyclonal antibody reached 1:128 000. Western blotting results revealed that both purified polyclonal antibodies could specifically bind to a purified 85 kD T. gondii protein predicted as TgVP1. The protein detected by these two polyclonal antibodies was distributed in the cytoplasm of T. gondii tachyzoite, and this distribution pattern was consistent with that of acidocalcisome.
Conclusion: The peptide-based method of antibody generation is efficient and the obtained TgVP1 polyclonal antibodies possess a high specificity to facilitate further study of T. gondii acidocalcisome and the diagnosis of toxoplasmosis.