Rational cytokine and receptor engineering for enhanced safety and efficacy of cancer immunotherapy

The emergence of immunotherapy, including immune checkpoint blockade (ICB) and the adoptive transfer of cytotoxic lymphocytes, such as CAR-T cell therapy, has revolutionized cancer treatment. However, these therapies still face significant challenges in terms of both safety and efficacy. In this Ph.D. thesis, I developed several protein and receptor engineering strategies to enhance the safety and efficacy of cytokine-based therapies and CAR-T cell therapy against solid tumours.
In the first part of the dissertation, I designed and developed both OFF-switch and ON-switch systems to control therapeutic activity by using chemically-responsive domains. In one example, I engineered cytokines activity by selectively masking the receptor binding site with a fused chemically-responsive domain, which is released upon addition of a trigger molecule. I successfully identified switchable mutants for three different cytokines, including IL-2, IL-10, and IL-15, demonstrating significant drug-controllability in mouse models.
In the second part of the thesis, I focused on enhancing the efficacy of CAR-T cell therapies by modulating their biomechanical properties. To enhance the cytotoxicity of CAR-T cells through modulation immune synapse strength, I designed a new type of CAR by fusing the actin-binding domain of integrins with the cytoplasmic tail of a second-generation CAR. These mechanically strengthened CAR-T cells formed highly stable immune synapse with target cells and exhibited improved cytotoxicity in vitro and in vivo.