DC-derived Exosomes (DEXs)
Dendritic cell (DC)-based vaccines have become a significant approach in cancer immunotherapy. Nonetheless, their application outside of clinical trials faces challenges due to the complexities associated with cell therapy. Additionally, the functionality of DCs can be compromised in cancer patients, further complicating their use. To address these issues, DC-derived exosomes (DEXs) have been developed as an alternative cancer vaccine strategy.
What are DEXs?
DEXs are nanometer-sized membrane vesicles secreted by live dendritic cells. They typically range from 30 to 100 nm in size and are formed by the inward budding of endosomal membranes within the cell. DEXs are rich in molecular components such as functional MHC-peptide complexes and costimulatory molecules, which are crucial for interacting with immune cells and eliciting an immune response. This molecular composition enables DEXs to serve as a potent and more stable alternative to whole DCs in cancer vaccination strategies.
Antigen Presentation
DEXs carry functional MHC-peptide complexes that present tumor antigens to T cells, similar to dendritic cells, which is crucial for initiating an adaptive immune response.
Activation of T cells
Through their costimulatory molecules, DEXs activate cytotoxic T lymphocytes (CTLs), which recognize and destroy tumor cells presenting the same antigens.
Inducing Immune Memory
DEXs help activate memory T cells, providing long-term protection against tumor recurrence.
Modulating Tumor TME
DEXs can influence other immune cells, like natural killer (NK) cells and B cells, enhancing their anti-tumor activities and suppressing the immunosuppressive environment that tumors create.
Enhance Immune Response
By interacting with various components of the immune system, DEXs boost the overall anti-tumor immune response, leading to tumor cell destruction and limiting tumor growth and metastasis.
Applications of DC-derived Exosomes
Development
