Minipigs as an animal model for dermal vaccine delivery

Appropriate animal models for intradermal vaccine delivery are scarce. Given the high similarity of their skin anatomy to that of humans, minipigs may be a suitable model for dermal vaccine delivery. Here we describe the immunization of Göttingen minipigs by using intradermal and intramuscular delivery of hepatitis B surface antigen (HBsAg). Intradermal vaccine delivery by needle and syringe and by needle-free jet injection induced humoral antiHBsAg responses. Priming immunization by using the disposable syringe jet injector (DSJI) resulted in a higher antibody titer than did conventional intradermal immunization and a titer comparable to that after intramuscular vaccination with HBsAg and Al(OH)3 adjuvant. This study highlights the utility of the minipig model in vaccine studies assessing the efficacy of conventional and novel methods of dermal delivery. Moreover, we include suggestions regarding working with minipigs during dermal vaccine delivery studies, thereby fostering future work in this area of vaccinology.