library_construction_protocol: PBMCs were fixed using Parse fixation reagents, frozen at -80°C for less than 6 months, and prepped according to Parse Evercode WT Mega v2 protocol. In this combinatorial split pool barcoding process, samples were first loaded into a 96-well plate and underwent reverse transcription with barcoded primers, pooled, split and barcoded again, followed by cell lysis using Parse reagents. According to Parse Evercode WT Mega v2 protocol. First, cDNA was amplified, then underwent fragmentation, adaptor ligation, sublibrary index PCR, and double-sided size selection. Sequencing was performed on a NovaSeq S4 instrument (Illumina; Chan Zuckerberg Biohub). The read structure was paired-end with i7 index, i5 index, and the 4th barcode (6bp) that tags each sublibrary acting as a standard Illumina index.