Ear Pinna: A Privileged DNA Electroporation Site for Inducing StrongTh1 Immune Responses

摘要

DNA vaccination appears a very attractive approach for inducing immune responses towards the encoded antigen,but studies in large animals and in humans revealed weaknesses of such responses. In this study, we evaluated a newapproach based on a new device combining DNA vaccination with electroporation (EP) at the ear pinna site. Under optimalEP conditions, the expression of the DNA encoded antigen and the induced immune responses were considerably increased.Very interestingly, DNA vaccination using EP at the ear pinna induced much stronger cellular immune responsesthan at the flank skin although antigen expression was similar at both sites. As compared to vaccination at the ear pinnawithout EP, IFN- but not IL-4 production by splenocytes from immunized mice was significantly enhanced. In contrast,IL-4 but not IFN- production was increased by EP at the flank skin. The vaccination site of the ear pinna combined withEP route even provided therapeutic effects in a mouse tumor model.In conclusion, this study highlights the ear pinna as a privileged site for the induction of strong Th1 polarized cellular immunityagainst a defined antigen when combining DNA vaccination with EP.