Abstract
Transcutaneous immunization is a new method of vaccination that utilizes a topical application of antigen to intact skin for induction of immune responses. In this study, we have assessed the potential for the application of transcutaneous immunization for the development of a novel vaccine- delivery system. When BALB/c mice were immunized with ovalbumin (OVA) by direct application to shaved skin, OVA-specific serum IgG antibody responses were induced ; however, none was induced in saliva. On the other hand, when OVA was given with cholera toxin (CT) as adjuvant, higher levels of OVA-specific serum IgG antibody responses were induced than that of OVA alone. Furthermore, OVA-specific IgG antibody responses were detected in the saliva of mice immunized with OVA plus CT. Antibody-forming cell (AFC) analysis confirmed the antibody titers by revealing significant numbers of OVA-specific IgG AFCs in the spleen and salivary gland. In addition, mononuclear cells from the spleen and cervical lymph nodes of mice immunized with OVA plus CT exhibited significant levels of proliferative responses when restimulated with OVA in vitro. These results indicate that transcutaneous immunization may be an effective vaccine delivery system for the induction of protein antigen-specific antibody responses in the oral cavity.