Fig. 6: Antibody responses to rationally designed HCV-1 sE1E2.Cut1+2.SPYΔN heterodimer and SApNP vaccines in mice.
a Schematic of the mouse immunization regimen for HCV-1 sE1E2.Cut1+2.SPYΔN vaccines (n = 8 mice/group). Mice received 200 μl of antigen/AH + CpG containing 10 μg of antigen and 100 μl of adjuvant via intraperitoneal (i.p.) injection at weeks 0, 3, 6, and 9. b Longitudinal serum NAb responses induced by HCV-1 sE1E2, FR, and I3-01v9a vaccines against genotype 1a H77 HCVpp. Serum samples from weeks 0, 2, 5, 8, and 11 were tested in neutralization assays to determine 50% inhibitory dilution (ID50) titers. c Endpoint NAb responses induced by HCV-1 sE1E2, FR, and I3-01v9a vaccines against genotype 3 UKNP3.1.2, genotype 4 UKNP4.2.2 and ED43, and genotype 5 UKNP5.2.1 HCVpps. Week-11 serum was tested. NAb responses induced by unmodified, Kif-treated, and Kif/endo F-treated HCV-1 sE1E2.Cut1+2.SPYΔN dimer vaccines (produced in ExpiCHO cells) against d H77 HCVpp at weeks 2, 5, 8, and 11 and e UKNP3.1.2, UKNP4.2.2, ED43, and UKNP5.2.1 HCVpps at week 11. NAb responses induced by unmodified and Kif-treated HCV-1 sE1E2.Cut1+2.SPYΔN-10GS-FR SApNP vaccines against f H77 HCVpp at weeks 2, 5, 8, and 11, and g UKNP3.1.2, UKNP4.2.2, ED43, and UKNP5.2.1 HCVpps at week 11. NAb responses induced by unmodified and Kif-treated HCV-1 sE1E2.Cut1+2.SPYΔN-5GS-I3-01v9a-L7P SApNP vaccines against h H77 HCVpp at weeks 2, 5, 8, and 11 and i UKNP3.1.2, UKNP4.2.2, ED43, and UKNP5.2.1 HCVpps at week 11. In (b–i), ID50 titers were calculated from HCVpp neutralization assays (0–100% constraint), with geometric means labeled. Data points are shown as geometric mean ± geometric SD. Data were analyzed using one-way ANOVA followed by Tukey’s post hoc test (each time point) or two-tailed unpaired t-tests (two-group comparisons). Statistical significance is indicated as ns (not significant) and *p < 0.05. The schematic in (a) was created in BioRender. https://BioRender.com/o89v779.
