After the perichondrium was stripped on ice immediately, all auricular cartilage  samples were minced into ~1 mm2 pieces and digested for 10 minutes with trypsin at 37°C to remove residual tissue attached to cartilage tissue. The cell suspension was loaded onto the Chromium single-cell controller (10x Genomics, USA) to generate single-cell gel beads in the emulsion (GEMs) by using Single Cell 3′ Library and Gel Bead Kit V3 (10x Genomics, USA) and Chromium Single Cell A Chip Kit (10x Genomics, USA) (performed by CapitalBio Technology, Beijing)