The tissue was cut into as small blocks as possible by scissors, and digested with 2 mg/ml. collagenase IV (2091GR001, BioFRoXX, Guangzhou, China) in the presence of 0.1 mg/ml DNase (Roche, Basel, Switzerland) for 20 min and ground by gentleMACS Dissociatir (Miltenyi Biotec, Germany) to obtain a single-cell suspension. Afterward, the cells were filtered with a 70-um cell strainer (Corning). Mononuclear cells were isolated from Ficoll-Paque Plus (17-1440-03; GE Healthcare) density gradient (lymphoprep; axis shield). Sorted single-cell suspension, 10x 3' barcoded gel beads, and oil was loaded into Chromium Single Cell B Chip to capture single cells in nanoliter-scale oil droplets by Chromium Controller and to generate Gel Bead-In-EMulsions (GEMs). Full-length cDNA libraries were prepared by incubation of GEMs in a thermocycler machine. GEMs containing cDNAs were broken and all single-cell cDNA libraries were pooled together, cleaned using DynaBeads MyOne Silane beads (PN 37002D; Fisher), and preampliﬁed by PCR to generate sufﬁcient mass for sequencing library construction. Sequencing libraries were constructed by following the steps cDNA fragmentation, end repair and A-tailing, size selection by SPRIselect beads (PN B23318; Beckman Coulter), adaptor ligation, sample index PCR ampliﬁcation, and repeat SPRIselect beads size selection.