Description
NK cell development, maturation, and activation by cytokines is driven by alterations in gene expression mediated by activation and repression or transcriptional programs. In particular, we have extensively studied the role of STAT3 in human NK cells. This was based in part on a method we developed for in vitro expansion of large numbers of highly active NK cells using a genetically-modified feeder cell expressing 4-1BBL and membrane-bound IL-21. To dissect the various gene expression profiles induced by IL-21 from the various other signals received from the feeder cell, we purified peripheral NK cells from 4 healthy subjects (naïve, N), expanded NK cells for 14 days using CSTX002 feeder cells (expanded, E), and extracted RNA from the cells without (Neg) or after (Pos) the cells were activated with IL-21. We then performed RNA sequencing on each sample. Overall design: NK cells were purified from buffy coats obtained from 4 normal healthy blood-bank donors using RosetteSep NK for negative depletion of other cell subsets. NK cells were expanded by weekly stimulation with irradiated CSTX002 feeder cells. Naïve or expanded NK cells were stimulated for 30 minutes with 20 ng/ml recombinant human IL-21. Total RNA was prepared using the Total RNA Purification Plus Kit (Norgen Biotek, Ontario, ON, Canada). Libraries were prepared using the TruSeq RNA Sample Preparation Kit (Illumina Inc., San Diego, CA). 60–80 million paired-end 150 bp sequence reads per library were generated using the Illumina HiSeq4000 platform.