Journal: International Journal of Nanomedicine
Article Title: cGAMP-Loaded M2e Nanovaccine Elicits Cross-Reactive Immunity and Mitigates H6N1 Avian Influenza Infection in Chickens
doi: 10.2147/IJN.S607946
Figure Lengend Snippet: M2e-specific antibody responses and cross-type reactivity induced by the M2e nanoshell vaccine. ( A ) Schematic diagram of the immunization schedule. SPF chickens were divided into three groups (n = 6 per group) and subcutaneously immunized on days 0, 21, and 42 with NS (M2e+cGAMP), M2e formulated with ISA 71 VG (oil-based adjuvant), or left unvaccinated. Blood samples were collected on days 21, 42, 56, 77, and 98 for serological analysis. ( B ) Detection of M2e-specific IgG titers in sera collected at multiple time points after immunization. M2e-specific IgG levels were determined by ELISA, and endpoint titers were defined as the highest serum dilution yielding an OD 4 50 value of 0.2. Statistical analysis was performed using one-way ANOVA followed by Dunnett’s multiple comparisons test at each time point to compare antibody titers among the three groups. Data are expressed as mean ± SEM. (*p < 0.05). ( C ) Schematic illustration of cross-reactivity ICC testing. Sera from vaccinated chickens were incubated with MDCK cells infected with seven influenza A strains (rgH5N1, H6N1, rgH7N9, H1N1 PR8, H1N2, pdmH1N1, and H3N2) to evaluate antibody recognition of influenza-infected cells expressing M2e. ( D ) Cells infected with different viruses were fixed and incubated with sera collected from chickens immunized subcutaneously with a single dose of NS (M2e+cGAMP), followed by staining with anti-chicken IgG and DAB chromogenic detection. Uninfected MDCK cells served as negative controls. Positive brown staining indicates specific binding of M2e-induced antibodies to influenza-infected cells. (Scale bar = 50 µm).
Article Snippet: The Madin-Darby Canine Kidney (MDCK) cell line (ATCC CCL-34) was used in this study.
Techniques: Adjuvant, Enzyme-linked Immunosorbent Assay, Incubation, Infection, Expressing, Staining, Binding Assay