A biodegradable polymeric nanoparticle vaccine for combating Acinetobacter baumannii infection

The ESKAPE pathogens, known for their high virulence and multidrug resistance, are associated with high mortality rates and pose a serious threat to public health and biosafety. Vaccination is a crucial preventive measure against these infections, yet current vaccine platforms face limitations in biocompatibility, stability, and immunogenicity. To address this, a polymeric nano-vaccine (NP-VAC) with potent immunogenic activity and a favorable safety profile was developed in this study. Experimental results demonstrated that NP-VAC exhibited good biosafety toward normal cells. Furthermore, it effectively activated the inflammasome, promoted dendritic cell maturation (DCs), and demonstrated strong immunostimulatory capacity. In a challenge experiment, mice pre-immunized with NP-VAC achieved a 100% survival rate following a lethal dose of Acinetobacter baumannii infection. In conclusion, NP-VAC shows excellent performance in safety, immune activation, and protective efficacy, providing a feasible strategy for developing novel nano-vaccines against drug-resistant bacterial infections.