library_construction_protocol: RNA was extracted from sEVs using Qiagen RNeasy Micro kit according to the manufacturer's instructions, including an on-column DNase treatment. RNA was also extracted from ½ of the sEV-source cells using Qiagen RNeasy Mini kit according to manufacturer's instructions including on-column DNase treatment. cDNA from sEV RNA and cell RNA was prepared using NEBNext® Single Cell/Low Input RNA Library Prep Kit for Illumina® (E6421), which utilizes poly-DT primed cDNA synthesis to enrich for poly-adenylated transcripts. Libraries were amplified with 15 cycles of PCR. Barcoded sequencing libraries were prepared using Illumina's Nextera-XT DNA Library Preparation Kit (FC-131-1096) and IDT for Illumina Nextera DNA unique dual indexes (20027215).