Biomaterial-based vaccines for cancer immunotherapy
Harnessing the immune system to treat cancer has been a goal in medicine for over a century, driven by the potential of providing specific, durable, and adaptive reactivity towards tumors. Recent success of checkpoint blockade antibodies and adoptive T cell transfer in clinical trials demonstrated the great potential of cancer immunotherapy, but also indicated the importance of understanding the dynamic interactions between the immune system and tumors. I am investigating the mechanisms of tumor-induced immunosuppression, and developing biomaterial-based cancer vaccines that can create a physical environment in the body to actively recruit and program immune cells in order to overcome the suppressive microenvironment of tumors.
Influence of mechanical cues in stem cell biology
Besides soluble factors, cells also sense and respond to the physical cues from their surroundings such as the stiffness of the extracellular matrix (ECM) and the physical contact of neighboring cells. These mechanical cues play an important role in stem cell fate during development and regeneration. To investigate how stem cell behaviors such as migration, proliferation, and differentiation are regulated by various mechanical signals, I am developing new biomaterials that mimic different aspects of the mechanical properties of natural ECM, and using them as substrates to culture mesenchymal stem cells and study the mechanotransduction pathways. These findings are then used to design and create biomaterials for tissue regeneration.
Nanomaterials for tumor imaging and drug delivery
Delivery of imaging probes and anticancer drugs to the tumors is a key challenge in cancer diagnosis and treatment, as molecular imaging agents and drugs permeate equally well within healthy and tumor vasculature. Nanoparticles, in contrast, accumulate in the tumors much more readily because of the enhanced permeability and retention (EPR) effect. However, many nanomaterials are toxic and can provoke acute or chronic side effects. To address this problem, I am designing and synthesizing nanoparticles that are non-toxic and biodegradable. These nanoparticles are also engineered to communicate through external signals (e.g. electromagnetic radiation) and execute diagnostic or therapeutic function only when in the tumor milieu.