Enhancing the structural stability of P29-targeted monoclonal antibodies via β-hydroxybutyrylation modification improves their therapeutic performance in alveolar echinococcosis.

BACKGROUND: Alveolar echinococcosis (AE), a severe parasitic infection often likened to "parasitic cancer", still lacks effective treatments. Although our earlier ork on the P29 monoclonal antibody (P29 mAb) against the parasite-derived P29 antigen showed potential, its efficacy remained limited, prompting the need for improved biologic agents. METHODS: We applied β-hydroxybutyrylation (Kbhb) modification to engineer an enhanced antibody, P29 mAb(Kbhb), and comprehensively evaluated its properties using surface plasmon resonance, protease resistance assays, pharmacokinetic studies in C57BL/6 mice, and histopathological analysis of alveolar hydatid cysts. RESULTS: The modified antibody retained high antigen-binding affinity (KD = 343 pM) and exhibited markedly increased resistance to proteolytic degradation, with a 1.75-fold improvement in serum persistence after 5 weeks. Furthermore, in a murine model of AE, P29 mAb(Kbhb) significantly inhibited protoscolex regeneration and induced apoptosis of cyst wall cells relative to the unmodified antibody. CONCLUSION: Our results establish a novel connection between protein engineering and antiparasitic therapy, illustrating that Kbhb modification not only augments the efficacy of anti-AE antibodies but also offers a versatile strategy for enhancing antibody stability and half-life. This offers a potential strategy for developing new treatments against neglected zoonotic diseases via tailored post-translational modifications.