Fig. 5: Biodistribution and in vivo CAR-M manufacturing efficiency mediated by CAR^mRNA@aCD206 sEV.

a The biodistribution of CAR^mRNA@aCD206 sEVs after intravenous or inhalation administration in a lung metastatic tumor model (n = 3 mice). b The biodistribution of CAR^mRNA@aCD206 sEV over time after inhalation in a lung metastatic tumor model (n = 3 mice). c The expression of Fluc in the major organs 24 h after inhalation of PBS or Fluc^mRNA@aCD206 sEV (n = 3 mice). Fluc as a surrogate marker for CAR expression. d Representative flow cytometry images (left) and statistical analysis (right) showing CAR protein expression in macrophages 24 h after inhalation of the indicated agents (n = 6 mice). Gated in macrophages. G1: PBS, G2: Mock^mRNA@aCD206 sEV, G3: CAR^mRNA@sEV, G4: CAR^mRNA@aHA sEV, G5: CAR^mRNA@aCD206 sEV. e Representative flow cytometry images (left) and statistical analysis (right) showing CAR protein expression in macrophages in response to varying concentrations of CAR^mRNA@aCD206 sEVs (n = 6 mice). f Representative flow cytometry images (left) and statistical analysis (right) showing the percentage of various immune cells (macrophages, dendritic cells, T cells and B cells) among CAR⁺ immune cells in the tumor tissue (n = 6 mice). Gated in CAR⁺ immune cells. g Representative flow cytometry plots (left) and statistical analysis (right) showing CAR protein expression in macrophages over time after inhalation of CAR^mRNA@aCD206 sEV (n = 6 mice). h Representative immunofluorescence images exhibiting CAR (green) macrophages (F4/80, red) in tumor tissues harvested 24 h after CAR^mRNA@aCD206 sEV inhalation (n = 3 mice). Scale bar: 20 μm. For (a–d) and (f, g), the dosage of sEVs used was 2 × 10⁹ mRNA copies/kg. Data are presented as mean ± SD. Data were analyzed using one-way ANOVA with Tukey’s test in (d). **** p ≤ 0.0001. Source data are provided as a Source Data file.