Fig. 4

HBc-specific IgG antibody titers (reciprocal serum dilution) induced by HBc VLPs, CpG@HBc VLPs, CpG-Au@HBc VLPs, CpG-Au + HBc VLPs, CFA/IFA + HBc VLPs, and PBS in BALB/C mice, respectively. Mice (n = 6) were intraperitoneally vaccinated on days 0, 7, 14, and 21 as described in the “Methods” section and detected antibody titers at the end of each week. The results represent anti-HBc titers as the means from six mice ± standard deviation (SD). The statistical significance of the results was analyzed (PBS group served as control, all the other groups contrasted with PBS group) and indicated: *p < 0.05; **p < 0.01