library_construction_protocol: Genomic DNA was extracted from approximately 1 million hMSCs using the DNeasy Blood and Tissue kit (Qiagen #69504) and was sonicated to ~300bp with a Covaris focused ultrasonicator Sonicated genomic DNA was ligated to methylated NEBNext Illumina adaptors using the NEBNext Ultra II DNA Library Prep (NEB, #E7645). Following bisulfite conversion with the EZ DNA methylation-lightning kit (Zymo Research, #D5030), libraries were amplified for 4 cycles using KAPA HiFi Uracil+ polymerase (KAPA Biosystems, #KK2801)