Monophosphoryl lipid A enhances mucosal and systemic immunity to vaccine antigens following intranasal administration

The induction of protective immunity stemming from vaccines delivered by mu cosal routes is dependent on the development of safe and effective mucosal adjuvants. The immunostimulant monophosphoryl lipid A (MPL(R)) was evaluate d for its ability to enhance both systemic and mucosal immunity to three di stinct antigens. Vaccines formulated with MP(R) and hepatitis B surface ant igen. tetanus toroid or influenza antigens were administered by intranasal delivery to mice. In each case the vaccines formulated with MPL(R) resulted in enhanced IgA titers from mucosal samples. Enhanced IgA concentrations w ere detected in samples from both local and distal mucosal sites. In additi on, the MPL(R) formulated vaccines induced systemic immunity characteristic of a Thl-type of response. Serum IgG2a antibody titers were elevated and c ytotoxic T cell activity was enhanced. (C) 2000 Elsevier Science Ltd. All r ights reserved.