Pre-clinical and clinical studies of epidermal powder immunization with an influenza vaccine

Antigen presentation is a critical step for the immune system to mount an antigen-specific immune response to invading pathogens. Delivering antigens directly to antigen presenting cells (APCs) is a promising way to improve the immunogenicity and effectiveness of vaccines. Epidermal powder immunization (EPI) delivers vaccine to the epidermis, the superficial layer of skin containing a large number of APCs, and has been shown to elicit augmented antibody responses and cellular immunity to the split influenza vaccine in small animals, nonhuman primates, and humans. EPI is safe and effective and holds promise for future human immunization with influenza and other vaccines. (C) 2004 Published by Elsevier B.V.