Proteomics analysis reveal early event molecular effectors of anti-CD19 CAR-T cell therapy in hematological cancer

Chimeric antigen receptor T-cell (CAR-T) therapy is at the forefront of cell immunotherapy. In this study, we generated an anti-CD19 CAR-Jurkat T cell line using a locally produced second-generation CD19 CAR construct, enabling us to analyze early proteomic changes crucial for understanding the signaling pathways and mechanisms of action of this CAR-T cell. SILAC-heavy tagged RAJI B-cells and anti-CD19 CAR-Jurkat T-cells were co-cultured for ten minutes. The proteomic profiles were obtained via DIA methodology on the Orbitrap Astral LC-MS/MS platform. The proteome was extensively covered, resulting in approximately 8800 protein identifications at 1% FDR. The effector CAR-Jurkat cells showed proteomic changes involving antigen presentation by CD74. The target RAJI B-cells exhibited more significant alterations, such as CD28, essential for T-cell survival and activation.