Abstract Hand, foot, and mouth disease (HFMD), caused by EV71 viral infection, has emerged as a serious public health concern in the Asia-Pacific region. The lack of effective treatment has led to a focus on controlling EV71 epidemics through development of vaccines. This study compares the potency of inactivated whole-virus EV71 vaccine with recombinant viral protein (rVP) subunit vaccine, administered by various immunization routes including intraperitoneal (IP), intradermal (ID), or using a microneedle (MN) patch. The MN patches, made of biocompatible silk proteins loaded with antigens and adjuvant, were applied directly to the skin. Both inactivated virus and rVPs vaccines generated substantial EV71 specific serum IgG, but only the former induced neutralizing antibody. Immunization with silk MN patches induced comparable neutralizing antibody titers to the IP and ID. These findings suggest that inactivated EV71 virus was superior to rVP subunit vaccine in stimulating neutralizing antibody and that with some fine-tuning; the silk-based MN patches are an effective and non-invasive delivery platform for EV71 and possibly for other immunogens.
Keywords: EV71 vaccine; recombinant protein; VP1; VP2; VP3; subunit; transdermal immunization; microneedle; silk