Preparation and Preliminary Application of Epitope Peptide-Based Antibody against Toxoplasma gondii GRA3

Toxoplasma gondii dense granule protein GRA3 has been shown to promote Toxoplasma gondii transmission and proliferation by interacting with the host cell endoplasmic reticulum (ER) through calcium-regulated cyclophilin ligands (CAMLG). Although many studies have focused on the interaction between the host cell endoplasmic reticulum and GRA3, no polyclonal antibodies (PcAbs) against GRA3 have been reported to date. According to the antigenicity prediction and exposure site analysis, three antigen peptide sequences were selected to prepare polyclonal antibodies targeting GRA3. Peptide scans revealed that the major antigenic epitope sequences were (125)ELYDRTDRPGLK(136), (202)FFRRRPKDGGAG(213), and (68)NEAGESYSSATSG(80), respectively. The GRA3 PcAb specifically recognized the GRA3 of T. gondii type II ME49. The development of PcAbs against GRA3 is expected to elucidate the molecular mechanisms by which GRA3 regulates host cell function and contribute to the development of diagnostic and therapeutic strategies for toxoplasmosis.

Automated summary

GRA3 protein is involved in the transmission and proliferation of Toxoplasma gondii by interacting with the host cell endoplasmic reticulum. Antigenic peptide sequences were selected to develop polyclonal antibodies against GRA3. The GRA3 PcAb specifically recognized GRA3 protein of Toxoplasma gondii type II ME49 strain. The development of GRA3 PcAbs is expected to reveal the molecular mechanisms of GRA3 in regulating host cell function and contribute to the development of diagnostic and therapeutic strategies for toxoplasmosis.