Polymeric nanocarrier-based adjuvants to enhance a locally produced mucosal coryza vaccine in chicken

Abstract

Infectious coryza (IC) is an acute upper respiratory disease of chicken caused by Avibacterium (A.) paragallinarum. This disease results in an increased culling rate in meat chicken and a marked decrease in egg production (10% to more than 40%) in laying and breeding hens. Vaccines were first used against IC and effectively controlled the disease. Nanotechnology provides an excellent way to develop a new generation of vaccines. NPs have been widely used in vaccine design as adjuvants and antigen delivery vehicles and as antibacterial agents; thus, they can be used as inactivators for bacterial culture. In this research, the antibacterial effects of several nanoparticles (NPs), such as silicon dioxide with chitosan (SiO₂-CS), oleoyl-chitosan (O.CS), silicon dioxide (SiO₂), and iron oxide (Fe₃O₄), on A. paragallinarum were studied. Additionally, different A. paragallinarum vaccines were made using the same nanomaterials at a concentration of 400 µg/ml to help control infectious coryza disease in chicken. A concentration of 400 µg/ml of all the NPs tested was the best concentration for the inactivation of A. paragallinarum. Additionally, this study showed that the infectious coryza vaccine adjuvanted with SiO₂ NPs had the highest immune response, followed by the infectious coryza vaccine adjuvanted with Fe₃O₄ NPs, the infectious coryza vaccine adjuvanted with SiO₂-CS NPs, and the infectious coryza vaccine adjuvanted with O.CS NPs in comparison with the infectious coryza vaccine adjuvanted with liquid paraffin (a commercial vaccine).

Keywords: A. Paragallinarum; Infectious coryza; Iron oxide; Nanomaterials; Nanovaccine; Oleyl chitosan; Silicon dioxide.

Figure 1

(A) the size distribution of the hydrodynamic diameter (in nm) of O.CS, SiO₂, SiO₂-CS, and Fe₃O₄ NPs determined via dynamic light scattering (DLS), as well as (B) their zeta potentials, and (C) zeta potentials of coryza (C) inactivated with commercial vaccine (Comm-Vaccine_C), O.CS_C, SiO₂_C, SiO₂-CS_C, and Fe₃O₄_C NPs.

Figure 2

Transmission electron microscopy (TEM) images display the prepared nanoparticles, including O.CS nanoparticles shown in both an overall view (A) and –ve window view (a), SiO₂-CS nanoparticles displayed in an overall view (B) and –ve window (depicting images with reverse grayscale) to observe a close-up view (b), SiO₂ nanoparticles (C), and Fe₃O₄ nanoparticles (D) and a close-up view. (E–H) The morphology of the synthesized samples was confirmed by SEM analysis.

Figure 3

X-ray diffraction (XRD) patterns illustrating the characteristics of O.CS, SiO₂, SiO₂-CS, and Fe₃O₄.

Figure 4

Results of the inactivation effect of different concentrations of O.CS, Si₂O, SiO₂-CS, and Fe₃O₄ nanomaterials on A. paragallinarum growth cultured in brain heart infusion agar (BHI).

Figure 5

Confocal images of live and dead A. paragallinarum stained with AO and PI, respectively (scale bar = 20 µm).

Figure 6

Cell viability percentage of A. paragallinarum after incubation with different concentrations of O.CS, SiO₂, SiO₂-CS, and Fe₃O₄ for 24 h. Statistically significant differences were *p < 0.0332, **p < 0.0021, ***p < 0.0002, and ****p < 0.0001.

Figure 7

Geometric mean hemagglutinating antibody titers against A. paragallinarum serovar A in chicken sera after vaccination with O.CS, SiO₂, SiO₂-CS, and Fe₃O₄ nanovaccines and the + ve control vaccine. The (A) graph displays data pertaining to each vaccine throughout the experiment, whereas the (B) graph illustrates data for nanovaccines over each week. Statistical analysis, including both one- and two-way ANOVA, was performed to compare all nanovaccines against the + ve control group. Significance levels are denoted as *p < 0.0332, **p < 0.0021, ***p < 0.0002, and ****p < 0.0001. The term "bW" refers to the postboostering week.

Figure 8

Geometric mean hemagglutinating antibody titer against A. paragallinarum serovar B in the sera of chicken vaccinated with O.CS, SiO₂, SiO₂-CS, and Fe₃O₄ nanovaccines and the + ve control vaccine. The (A) graph displays data pertaining to each vaccine throughout the experiment, whereas the (B) graph illustrates data for nanovaccines over each week. Statistical analysis, including both one- and two-way ANOVA, was performed to compare all nanovaccines against the + ve control group. Significance levels are denoted as *p < 0.0332, **p < 0.0021, ***p < 0.0002, and ****p < 0.0001. The term "bW" refers to the postboostering week.

Figure 9

Geometric mean hemagglutinating antibody titer against A. paragallinarum serovar C in the sera of chicken vaccinated with O.CS, SiO₂, SiO₂-CS, and Fe₃O₄ nanovaccines and the + ve control vaccine. The (A) graph displays data pertaining to each vaccine throughout the experiment, whereas the (B) graph illustrates data for nanovaccines over each week. Statistical analysis, including both one- and two-way ANOVA, was performed to compare all nanovaccines against the + ve control group. Significance levels are denoted as *p < 0.0332, **p < 0.0021, ***p < 0.0002, and ****p < 0.0001. The term "bW" refers to the postboostering week.