Fig. 5.

Serum IgG subclasses induced by intranasal immunization of OVA plus CpG ODN-loaded DOTAP/DC-chol liposomes in BALB/c mice. BALB/c female mice were immunized intranasally with PBS, OVA (5 µg/mouse) alone, OVA (5 µg/mouse) plus DOTAP/DC-chol liposomes, or OVA (5 µg/mouse) plus CpG ODN-loaded DOTAP/DC-chol liposomes on days 0 and 7. Serum samples were collected on day 14. The anti-OVA IgG1 and IgG2a levels in serum were detected by ELISA assay as described in the “Methods” section. The data were obtained from three independent experiments. The box-plot shows the median value with the 25th–75th percentiles and the error bars indicate the 5th–95th percentiles. The symbols in box plots represent individual mice (PBS, n = 10; OVA, n = 10; OVA plus liposome, n = 10; OVA plus CpG-loaded liposome, n = 12; OVA plus CpG ODN, n = 8). Significance was assessed using the Kruskal–Wallis with Dunn’s post hoc test: *p < 0.05, NS not significant