{Reference Type}: Journal Article {Title}: In vivo production of CAR-T cells using virus-mimetic fusogenic nanovesicles. {Author}: Zhao G;Zhang Y;Xu CF;Wang J; {Journal}: Sci Bull (Beijing) {Volume}: 69 {Issue}: 3 {Year}: 2024 Feb 15 {Factor}: 20.577 {DOI}: 10.1016/j.scib.2023.11.055 {Abstract}: Engineered T cells expressing chimeric antigen receptor (CAR) exhibit high response rates in B-cell malignancy treatments and possess therapeutic potentials against various diseases. However, the complicated ex vivo production process of CAR-T cells limits their application. Herein, we use virus-mimetic fusogenic nanovesicles (FuNVs) to produce CAR-T cells in vivo via membrane fusion-mediated CAR protein delivery. Briefly, the FuNVs are modified using T-cell fusogen, adapted from measles virus or reovirus fusogens via displaying anti-CD3 single-chain variable fragment. The FuNVs can efficiently fuse with the T-cell membrane in vivo, thereby delivering the loaded anti-CD19 (αCD19) CAR protein onto T-cells to produce αCD19 CAR-T cells. These αCD19 CAR-T cells alone or in combination with anti-OX40 antibodies can treat B-cell lymphoma without inducing cytokine release syndrome. Thus, our strategy provides a novel method for engineering T cells into CAR-T cells in vivo and can further be employed to deliver other therapeutic membrane proteins.