DCs are professional antigen-presenting cells (APCs) that regulate all aspects of the adaptive immune response. However, our knowledge is very limited to how DC subsets regulate humoral immune responses (antibody responses). Since many vaccines’ effectiveness relies on the induction of neutralizing antibody (humoral) responses, understanding the mechanism by which DC subsets regulate humoral immune responses is crucial for the development of more effective vaccines. In this project, we aim to determine the mechanistic aspects of DC-regulated humoral immune responses.

The production and wide use of artificial antigen-presenting cells (aAPCs) in the clinic as cancer immunotherapeutics are hindered by the need for identifying immunogenic cancer antigens and production of recombinant patient-specific major histocompatibility complexes (MHC) loaded with these peptides. To overcome these limitations, we tested the idea of whether peptide-MHCs can directly be captured from cell lysates, including cancer cells using affinity beads, and used to initiate T cell responses. In theory, these affinity beads covered with the unknown peptide-MHC repertoire captured from the cancer cells could interact with a wide range of antigen-specific T cells and promote anti-cancer responses. Indeed, we found that we can successfully pull-down peptide-MHCs from cell lysates and the aAPCs generated using this technique were able to induce antigen-specific cytotoxic effector T cell responses that led to in vitro and in vivo tumor cell killing. In summary, we present here a novel technique to generate patient-specific aAPCs, that might have the potential to revolutionize the field of cancer vaccines and provide patients with a vaccine in matters of days at minimal costs.