Engineering CAR-T cells to overcome glycosylation-driven tumour resistance

ongoing

T cells engineered to express tumour-specific chimeric antigen receptors (CAR) proved effective against B-cell tumours. However, as the technology moves to solid cancers, clinical responses have not been as robust. In this setting, several barriers need to be overcome, including poor tumour recognition and a highly immunosuppressive tumour microenvironment (TME). Altered glycosylation is a hallmark of cancer, often manifesting as incomplete synthesis of O-glycans and increased branching of N-glycans. Glycosylation can mask epitopes to antibodies recognition and suppress anticancer immunity. My Unit was the first to report that N-glycans protect tumours from CAR-T cells and that pharmacological inhibition of N-glycosylation improves efficacy of CAR-T cell therapy in solid malignancies. With the aim of generating a single cell product able to safely offset multiple barriers of tumour resistance, I propose to engineer CAR-T cells to locally express an enzyme able to de-glycosylate tumour and TME cells. This goal will be achieved through the selection of a mutant able to deglycosylate the surface proteome of target cells. To regulate its function in CAR-T cells, I plan to test different systems based on the use of specific promoters, the inclusion of artificial miRNA target sequences, or the generation of a transmembrane variant. A deep characterization of the selected product will be performed in mice reconstituted with a human haemopoietic system. This model will allow to study the efficacy and safety of the proposed approach, and to assess its ability to remodel the TME toward a pro-inflammatory state. I believe that this project will have an immediate impact on cancer immunotherapy, will fuel the development of antiviral approaches and will provide new technological platforms. I have a deep knowledge of CAR-T cell therapy and have established a great network in the field. Despite ambitious, I believe I have the right skills and tools to make this project a reality.