GSM7229892
For single cell RNA sequencing experiment, 2x105 cells were seeded in triplicate in 6 well plates for 24 hours. Next, we collected cells using trypsin, washed them twice with PBS containing 3% BSA before adding 100ul of multiplexing oligos to each pellet. Following dissociation, cells were incubated for 5 min at room temperature before subsequent washes with 2 ml of PBS containing 3% BSA. Cells were resuspended in 500 ul of PBS containing 1% BSA, counted, and 1.5x105 cells from individual samples were pooled into one library. After cells viability assessment, the library was centrifuged (1200 RPM for 5 min), the supernatant removed, and the pellet was suspended to a final concentration of 1.5 million cells per ml.  We found that most samples had over 90% cell viability, therefore, samples were directly processed for library preparation without the need for cell sorting based on DAPI. For multiplexing, we used CellPlex, a cholesterol-modified oligonucleotide (CMO) cell tagging based approach from 10x Genomics.  We barcoded each sample (MCF7 and bone-derived MCF7) before pooling samples for single cell library preparation. CellPlex (10x Genomics)