SummaryChimeric antigen receptor T cell (CAR T) therapy has shown transformative potential in treating malignant tumours, with increasing global approval of CAR T products. However, high production costs and risks associated with viral vector based CAR T cells such as insertional mutagenesis and secondary tumour formation remain challenges. Our study introduces an innovative CAR T engineering approach using mRNA delivered via lipid nanoparticles (LNPs), aiming to reduce costs and enhance safety while maintaining strong anti tumour efficacy. We developed an LNP based transfection protocol for efficient delivery of mRNA encoding full human CAR constructs, achieving high CAR expression and significant cytotoxicity... More
SummaryChimeric antigen receptor T cell (CAR T) therapy has shown transformative potential in treating malignant tumours, with increasing global approval of CAR T products. However, high production costs and risks associated with viral vector based CAR T cells such as insertional mutagenesis and secondary tumour formation remain challenges. Our study introduces an innovative CAR T engineering approach using mRNA delivered via lipid nanoparticles (LNPs), aiming to reduce costs and enhance safety while maintaining strong anti tumour efficacy. We developed an LNP based transfection protocol for efficient delivery of mRNA encoding full human CAR constructs, achieving high CAR expression and significant cytotoxicity against leukaemic cells in vitro. Co culture with Raji cells showed increased cytokine secretion and tumour cell killing by mRNA LNP CAR T cells. Therapeutic efficacy was further demonstrated in an NOD scid IL2R null (NSG) mouse model with Raji engraftment, where treated mice exhibited marked tumour regression and extended survival. These findings underscore the potential of mRNA LNPs as a non viral, effective CAR T engineering platform, offering a promising alternative to traditional methods that could improve CAR T safety, efficacy and accessibility in clinical cancer immunotherapy.We introduce a novel CAR T cell engineering strategy utilizing mRNA laden lipid nanoparticles (mRNA LNPs) to address the challenges of viral vector based approaches, including insertional mutagenesis and high production costs. Humanized CAR mRNA targeting CD19 was encapsulated into LNPs using microfluidic mixing, achieving efficient transfection and robust CAR expression. Engineered CAR T cells exhibited potent cytotoxicity against leukaemic cells in vitro, demonstrated increased cytokine secretion and enhanced tumour killing in co culture systems. In vivo studies in NSG mice with Raji cell engraftment confirmed significant tumour regression and prolonged survival, highlighting mRNA LNP technology as a safer, scalable alternative for CAR T therapy.
