PBMCs were lysed in 700 mL of Trizol and then extracted using the miRNeasy Mini kit (Qiagen) with on-column DNase digestion. RNA quality was assessed using a TapeStation 4200 (Agilent) and then ten nanograms of total RNA was used as input for cDNA synthesis using the Clontech SMART-Seq v4 Ultra Low Input RNA kit (Takara Bio) according to the manufacturer's instructions. Amplified cDNA was fragmented and appended with dual-indexed barcodes using the Nextera XT DNA Library Preparation kit (Illumina). Libraries were validated by capillary electrophoresis on a TapeStation 4200 (Agilent), pooled at equimolar concentrations, and sequenced with PE100 reads on an Illumina NovaSeq 6000, yielding ~30 million reads per sample on average.