Immunogenicity and efficacy of intradermal tattoo immunization with adenoviral vector vaccines

Since intradermal delivery of DNA vaccines via tattoo device is an efficient strategy to induce antigen-specific immune responses, we evaluated this route of application for adenoviral vector vaccines in mice. Although expression levels were comparable after i.d. injection and i.d. tattoo immunization of adenoviral vectors, the tattoo application confined antigen expression to the upper layers of the dermis. Both delivery approaches resulted in strong CD8+ T-cell and humoral immune responses to three different antigens and conferred protection against mucosal challenge with respiratory syncytial virus. However, in contrast to results obtained with DNA vaccines, intradermal tattoo immunization did not provide any obvious advantage in comparison to simple intradermal injection of the adenoviral vector vaccines.