Whole blood from 27 anonymous blood donors were obtained at the central blood bank at Rigshospitalet, Copenhagen, and enriched for PBMCs using density centrifugation in Leucosep tubes before cryopreservation at -150°C in FCS plus 10% DMSO PBMCs from 21 hepatitis patients were collected and cryopreserved under protocol ID #1999-P004983 “Cell Mediated Immunity in Viral hepatitis ~15,000 cells were loaded (based on 55% recovery from 27,500 sorted cells) onto a Chromium Controller to yield a maximum of 9,000 cells with an intermediate/high doublet rate (6.9%). We utilized the 10x Genomics 5' v2 chemistry protocol supplied by 10x genomics allowing the cell barcode to be appended at the 5'-end of transcripts during capture. See https://elifesciences.org/articles/81810#s4 for further details. Downstream processing of mRNA and DNA barcodes is performed according to the manufacturer's instructions (Chromium Next GEM Single Cell 5' Reagent Kits v2 [Dual Index], with the Feature Barcode technology for Cell Surface Protein & Immune Receptor Mapping) (10x Genomics, USA). Targeted amplification was performed for 13 cycles and the products were separated according to size into <400 bp (DNA barcode-tags) and >400 bp (the TCR sequences) using 0.6× SPRIselect beads (Beckman Coulter, B23318).