Chronic Hepatitis B virus infection remains a major global public health problem, accounting for about 887,000 deaths in 2015. Perinatal and early childhood infections are strongly associated with developing chronic hepatitis B. Adding a birth dose of the hepatitis B vaccine (HepB BD) to routine childhood vaccination can prevent over 85% of these infections. However, HepB BD coverage remains low in many global regions, with shortages of birth attendants trained to vaccinate and limited HepB BD supply at birth. To address the challenges, we developed coated metal microneedle patches (cMNPs) and dissolvable microneedle patches (dMNPs) that deliver adjuvant‐free hepatitis B vaccine to the skin in a simple‐to‐administer manner. The dMNP contains micron‐scale, solid needles encapsulating vaccine antigen and dissolve in the skin, generating no sharps waste. We delivered HepB BD via cMNP to BALB/c mice and via dMNP to both mice and rhesus macaques. Both cMNP and dMNP were immunogenic, generating hepatitis B surface antibody levels similar to human seroprotection. Biomechanical analysis showed that at high forces the microneedles failed mechanically by yielding but microneedles partially blunted by axial compression were still able to penetrate skin. Overall, this study indicates that with further development, dMNPs could offer a method of vaccination to increase HepB BD access and reduce needle waste in developing countries.

The spontaneous fixation of penicillin G on guinea pig serum protein was studied. Serum albumin and Ig were shown to fix firmly over 95% of penicillin. Therefore, guinea pigs were immunized with penicillin alone or penicillin-autologous carrier protein conjugates. The production of hemagglutinating antibody, of MIF and the in vitro stimulation of lymphocytes were analyzed as immunological parameters. The results showed that in all cases the strongest immunological response was obtained with animals immunized with the protein-hapten conjugates, whereas no response could be obtained with the carrier protein alone. Finally it was shown that the conjugates significantly stimulated purified T cell population. These results suggest that the antigenic recognition of penicillin involves the participation of lymphocytes.