scRNA-seq of MC38 syngeneic colorectal tumors after FAP-CAR mRNA-LNP therapy

This study investigates the therapeutic potential of an mRNA–lipid nanoparticle (LNP)-based strategy delivering fibroblast activation protein (FAP)-specific chimeric antigen receptor (CAR) mRNA in colorectal cancer. Syngeneic colorectal mouse tumor models were treated with FAP-CAR mRNA-LNPs, and single-cell RNA sequencing (scRNA-seq) of tumor tissues was performed. The analysis aimed to explore mechanisms of tumor relapse following treatment, with a particular focus on the MIF–CD74 signaling axis. The data revealed heterogeneous immune and stromal cell states, highlighting immunosuppressive pathways associated with relapse. Overall design: MC38 syngeneic colorectal tumors were established in C57BL/6 mice and treated with FAP-CAR mRNA-LNPs in combination with 5-fluorouracil (5-FU), anti-PD1, and anti-CTLA4 antibodies. Tumor tissues were collected from two relapse cases and one untreated control for single-cell RNA sequencing (scRNA-seq).