A Multiepitope Peptide, rOmp22, Encapsulated in Chitosan-PLGA Nanoparticles as a Candidate Vaccine Against Acinetobacter baumannii Infection

• Published in: International journal of nanomedicine 2021-01, Vol.16, p.1819-1836
• Main Authors: Du, Xingran, Xue, Jianpeng, Jiang, Mingzi, Lin, Shaoqing, Huang, Yuzhen, Deng, Kaili, Shu, Lei, Xu, Hanmei, Li, Zeqing, Yao, Jing, Chen, Sixia, Shen, Ziyan, Feng, Ganzhu
• Format: Article
• Language: English
• Subjects: a. baumannii; A549 Cells; Acinetobacter baumannii - immunology; Acinetobacter Infections - blood; Acinetobacter Infections - immunology; Acinetobacter Infections - microbiology; Amino Acid Sequence; Animals; Antibiotics; Antibodies, Bacterial - immunology; Antigenic determinants; Antigens; Bacteria; Bacterial Load; Bacterial Vaccines - immunology; Biofilms; Bioinformatics; Body Weight; chitosan; Chitosan - chemistry; Deoxyribonucleic acid; DNA; Drug resistance in microorganisms; E coli; Enzymes; epitope vaccine; Epitopes - chemistry; Epitopes - immunology; Experiments; FDA approval; Female; Health aspects; Humans; Immunity, Humoral; Immunization; Immunoglobulin G; Immunoglobulin G - immunology; Infection; Interferon-gamma - metabolism; Interleukin-4 - metabolism; Laboratory animals; Lung - immunology; Lung - microbiology; Lung - pathology; Medical research; Medicine, Experimental; Mice; Mice, Inbred BALB C; Nanoparticles; Nanoparticles - chemistry; Nanoparticles - ultrastructure; Original Research; Peptides; Peptides - chemistry; Peptides - immunology; plga; Polylactic Acid-Polyglycolic Acid Copolymer - chemistry; polymeric nanoparticles; Polyvinyl alcohol; Proteins; Recombinant Proteins - isolation & purification; Spleen - pathology; Streptococcus infections; Survival Analysis; T cells; Vaccination; Vaccines; Virulence
• ISSN: 1178-2013; 1176-9114; 1178-2013
• DOI: 10.2147/IJN.S296527

The development of vaccines is a promising and cost-effective strategy to prevent emerging multidrug-resistant (MDR) ( ) infections. The purpose of this study was to prepare a multiepitope peptide nanovaccine and evaluate its immunogenicity and protective effect in BALB/c mice. The B-cell and T-cell epitopes of Omp22 from were predicted using bioinformatics methods and identified by immunological experiments. The optimal epitopes were conjugated in series by 6-aminocaproic acid and chemically synthesized multiepitope polypeptide rOmp22. Then, rOmp22 was encapsulated by chitosan (CS) and poly (lactic-co-glycolic) acid (PLGA) to prepare CS-PLGA-rOmp22 nanoparticles (NPs). The immunogenicity and immunoprotective efficacy of the vaccine were evaluated in BALB/c mice. CS-PLGA-rOmp22 NPs were small (mean size of 272.83 nm) with apparently spherical structures, positively charged (4.39 mV) and nontoxic to A549 cells. A high encapsulation efficiency (54.94%) and a continuous slow release pattern were achieved. Compared with nonencapsulated rOmp22, CS-PLGA-rOmp22 immunized BALB/c mice induced higher levels of rOmp22-specific IgG in serum and IFN-γ in splenocyte supernatant. Additionally, lung injury and bacterial burdens in the lung and blood were suppressed, and potent protection (57.14%-83.3%) against acute lethal intratracheal challenge was observed in BALB/c mice vaccinated with CS-PLGA-rOmp22. CS-PLGA-rOmp22 NPs elicited specific IgG antibodies, Th1 cellular immunity and protection against acute lethal intratracheal challenge. Our results indicate that this nanovaccine is a desirable candidate for preventing infection.