Optimized Mucosal Modified Vaccinia Virus Ankara Prime/Soluble gp120 Boost HIV Vaccination Regimen Induces Antibody Responses Similar to Those of an Intramuscular Regimen

Mucosal vaccination is proposed as a method of immunization able to induce protection against mucosal pathogens that is superior to protection provided by parenteral immunization. However, mucosal vaccination often induces serum antigen-specific immune responses of lower magnitude than those induced by parenteral immunization, making the comparison of mucosal and parenteral immunization difficult. We identified vaccine parameters that allowed an immunization regimen consisting of an i.n. prime followed by boosters administered by both i.n. and i.m. routes to induce serum antibody responses similar to those induced by i.m. prime/boost vaccination. Additional studies are needed to determine the potential benefit of mucosal immunization for HIV-1 and other mucosally transmitted pathogens.