SBIR TOPIC 081: ADJUVANT DEVELOPMENT FOR VACCINES AGAINST INFECTIOUS OR IMMUNE-MEDIATED DISEASES

Most infectious pathogens enter the host via mucosal surfaces. To provide a first line defense at these sites, vaccines are being developed to induce pathogen-specific mucosal IgA, in addition to systemic immunity achieved by administered vaccines. Only mucosal vaccination can induce both mucosal and parenteral IgG/IgA. Currently, only a few adjuvants have been licensed as vaccine components in the U.S., which are either not ideally formulated for mucosal delivery or their mechanisms of action are not well-defined. Several hurdles must be overcome in developing practical subunit mucosal vaccines, including poor immunogenicity, degradation of vaccines in a harsh mucosal environment, delivery of vaccines to mucosal immune inductive tissue, and modulation of the mucosal immune environment to ensure that oral tolerance does not develop. The goal of this proposal is to develop a novel mucosal adjuvant for oral vaccines against infectious diseases. Here we propose to tackle the above hurdles with three study components, i.e., 1) Further optimization of the novel molecular adjuvant C3d-CTB; 2) Evaluation of C3d-CTB efficacy in the context of an investigational new vaccine against Helicobacter pylori; and 3) Delivery of such novel H. pylori vaccine via oral route by the green algae Chlamydomonas reinhardtii as a bio-encapsulation vehicl