Figure 2. Design and in vitro cell testing of the aPDL1-CAR construct. (A) Structure of the aPDL1-CAR vector. The extracellular binding region consists of an anti-PDL1 scFv, the hinge and transmembrane domains correspond to CD8α, and the intracellular portion contains the signaling domains of 4-1BB and CD3ζ. The EGFP gene is linked by a 2A peptide sequence. (B) Transmitted light and fluorescence microscopy images of aPDL1-K562 cells in co-culture with PDL1-K562 cells or K562 cells for 4 h (200×). Green labeling corresponds to aPDL1-K562 cells, and red labeling indicates PDL1-K562 and K562 cells.