Enhancement of HBV vaccine immunogenicity with combination of CsA and IL-2 fusion protein in mice skin transplantation model

Abstract

Objective To study the effect on humoral immunity with combination of CsA and IL-2 fusion protein. Methods Forty C57/B6 mice were evenly divided into four groups,after receiving skin graft from DBA mouse.Mice in the experimental group was given CsA(30 mg/kg,ip) plus IL-2/Fc (1μg,ip) while the control group was only given CsA,each group was given HBV vaccine after skin graft surgery (2 μg,im),while blank group was only given vaccine after skin transplantation.The fourth group were left intact.Fourteen days later,the level of HBSAb,IL-4,IL-10,IFN-γ,IL-2 were measured with ELISA and IL-21and FoxP3 expression level and Tfh percentage of mixed lymphocytes detected. Results The HBSAb level in experimental group is significantly higher than that in the control group and the survival time of skin graft is longer than that in the control group ( F =29.886,P =0.010 ; F =29.772,P =0.011).IL-2,IFN-γ are significantly higher than that in the control group( F =18.156,P =0.0020;F =90.042,P =0.003 ),but the Th2 cytokines such as IL-4,IL-10 are lower ( F =42.102,P =0.009 ; F =23.734,P =0.015 ).The expression level of both IL-21and FoxP3 are significantly higher than control group( F =9.784,P =0.048 ;F =27.883,P =0.012). Conclusions Combination of CsA and IL-2 fusion protein can significantly enhance the immunogenicity of HBV vaccine and prolong graft survival time.It may be related to the higher expression level of IL-21and FoxP3. Key words: Hepatitis B, vaccines; Liver transplantation; Animal experimentation; Follicular helper T cell