%0 Journal Article %A Jiao, Xuanmao %A Wang, Richard Yan-Hui %A Qiu, Qi %A Alter, Harvey J. %A Shih, J. Wai-Kuo %T Enhanced hepatitis C virus NS3 specific Th1 immune responses induced by co-delivery of protein antigen and CpG with cationic liposomes %D 2004 %J Journal of General Virology, %V 85 %N 6 %P 1545-1553 %@ 1465-2099 %R https://doi.org/10.1099/vir.0.79896-0 %I Microbiology Society, %X Mice were immunized intramuscularly with free recombinant hepatitis C virus (HCV) NS3 (non-structural protein 3) protein, liposomes encapsulating rNS3 or rNS3 and CpG mixture, liposomes co-encapsulating rNS3 and CpG or liposomes co-encapsulating rNS3 and GpC. Liposomes co-encapsulating rNS3 and CpG induced a much higher titre of anti-HCV NS3 IgG and the dominant IgG subtype was IgG2a. Liposomes co-encapsulating rNS3 and GpC also induced high levels of anti-HCV NS3 IgG antibody, but the dominant IgG subtype was still IgG1, the same as in free HCV/NS3 immunized mice. Liposomes encapsulating rHCV NS3 and the mixture of rHCV NS3 and CpG did not increase the antibody response but switched the IgG subtype. A cytokine profile analysis revealed that the levels of Th1 cytokines in the mice immunized with liposomes co-encapsulating rHCV NS3 and CpG were significantly higher than in other mice while the levels of Th2 cytokine were significantly lower than in the mice immunized with naked rNS3. IL-12 in the mice immunized with liposome-NS3-CpG was significantly higher than in other mice. In conclusion, liposomes co-encapsulating HCV NS3 and CpG are a good candidate vaccine to induce strong Th1 immune responses against hepatitis C viruses. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.79896-0