Project description:PBMCs were stimulated with irradiated K562-mIL21 and 221-mIL21 feeder cells, respectively, as well as supplemented with IL-2 and IL-15. NK cells were purified from expanded cells using flow cytometry on day 7 and day 14 for RNA sequencing (RNA-Seq).
Project description:NK cell adoptive therapy is a promising cancer therapeutic approach, but there are significant challenges that limiting its feasibility and clinical efficacy. One difficulty is the paucity of clinical grade manufacturing platforms to support the large scale expansion of highly active NK cells. We created an NK cell feeder cell line termed 'NKF' through overexpressing membrane bound IL-21 that is capable of inducing robust and sustained proliferation (>10,000-fold expansion at 5 weeks) of highly cytotoxic NK cells. The expanded NK cells exhibit increased cytotoxic function against a panel of blood cancer and solid tumor cells as compared to IL-2-activated non-expanded NK cells. The NKF-expanded NK cells also demonstrate efficacy in mouse models of human sarcoma and T cell leukemia. Mechanistic studies revealed that membrane-bound IL-21 leads to an activation of a STAT3/c-Myc pathway and increased NK cell metabolism with a shift towards aerobic glycolysis. The NKF feeder cell line is a promising new platform that enables the large scale proliferation of highly active NK cells in support of large scale third party NK cell clinical studies that have been recently intiatied. These results also provide mechanistic insights into how membrane-bound IL-21 regulates NK cell expansion.
Project description:NK cells can potentially be used in allogeneic immunotherapy; however, for such use as off-the-shelf medicines, NK cells need to undergo ex vivo expansion, typically through activation with feeder cells, to generate enough cells for clinical applications. Upon stimulation with feeder cells, NK cells undergo profound changes in gene expression, altering their metabolic activity, cell cycle progression, and growth behavior. After examining the transcriptome and chromatin accessibility of NK cells before and 7 days after feeder cell activation, significant alterations were seen. These changes are even more pronounced in genome regions closer to enhancers. Several transcription factors, including AP-1, IRF4, STATs, T-bet, Eomes, and bHLHE40, which play key roles in NK cell development and immune response, exhibited differential binding activity between unstimulated and day 7 NK cells. Gene sets composed of target genes downstream of these transcription factors were also enriched at day 7, implying their involvement in NK cell activation. Moreover, we compared potential super-enhancer regions in NK cells before and after coculture, combined with the transcriptional activity of nearby genes. We identified stable and transcriptionally active super-enhancers in unstimulated and day 7 NK cells, as well as those that form or disappear after coculture initiation. The transcriptomic and epigenetic characterization of NK cells presented in this study could facilitate the ex vivo expansion and engineering of functionally superior NK cells.
Project description:Natural Killer (NK) cells present natural cytotoxicity against tumor cells, although their activity is increased after activation. NK cell activation depends on a complex intracellular signaling process mediated by activating and inhibitory receptors and the functional outcome depends on the integration of the activating and inhibitory signals received. Soluble cytokines and/or ligands on target cells bind the NK cell receptors, and hence, influence the final NK cell response: attack versus ignorance. We used microarrays to detail the global programme of gene expression underlying NK cell activation by IL-2, a MHC-I-deficient target cell (K562)+IL-2 and an EBV-target cell (R69). PBLs from 4 different donors were activated by 100 U/ml IL-2; K562+IL-2 or R69 cells. After 5 days we obtained RNA and miRNA from naïve NK cells or from NK cells activated with the above mentioned stimuli, with more than 90% of purity. The 16 RNA samples were used to generate cDNA libraries that were hybridized on Human Gene 1.1ST arrays (Affymetrix) and analyzed with the Affymetrix Gene Chip Command Console Software v3.0 (AGCC 3.0, Affymetrix®) and the Expression Console Software v1.1 (Affymetrix®).
Project description:K562 cells were treated with different HSP90 inhibitors (PuH71 and Coumermycin A1) and the CNV profil was compared to the parental K562 (untreated). In addition, the CNV profile of HSP90AB1 knockout K562 cells was analyzed.
Project description:Natural killer (NK) cells are innate lymphocytes recognized for their important role against tumor cells. NK cells expressing chimeric antigen receptors (CARs) have enhanced effector function against various type of cancer and are attractive contenders for the next generation of cancer immunotherapies. However, a number of factors have hindered the application of NK cells for cellular therapy, including their poor in vitro growth kinetics and relatively low starting percentages within the mononuclear cell fraction of peripheral blood or cord blood (CB). To overcome these limitations, we genetically-engineered human leukocyte antigen (HLA)-A- and HLA-B- K562 cells to enforce the expression of CD48, 4-1BBL, and membrane-bound IL-21 (mbIL21), creating a universal antigen presenting cell (uAPC) capable of stimulating their cognate receptors on NK cells. We have shown that uAPC can drive the expansion of both non-transduced (NT) and CAR-transduced CB derived NK cells by greater than 900-fold in 2 weeks of co-culture with excellent purity (>99.9%) and without indications of senescence/exhaustion. We confirmed that uAPC-expanded research- and clinical-grade NT and CAR-transduced NK cells have higher metabolic fitness and display enhanced effector function against tumor targets compared to the corresponding cell fractions cultured without uAPCs. This novel approach allowed the expansion of highly pure GMP-grade CAR NK cells at optimal cell numbers to be used for adoptive CAR NK cell-based cancer immunotherapy.
Project description:NK cells can potentially be used in allogeneic immunotherapy; however, for such use as off-the-shelf medicines, NK cells need to undergo ex vivo expansion, typically through activation with feeder cells, to generate enough cells for clinical applications. Upon stimulation with feeder cells, NK cells undergo profound changes in gene expression, altering their metabolic activity, cell cycle progression, and growth behavior. After examining the transcriptome and chromatin accessibility of NK cells before and 7 days after feeder cell activation, significant alterations were seen. These changes are even more pronounced in genome regions closer to enhancers. Several transcription factors, including AP-1, IRF4, STATs, T-bet, Eomes, and bHLHE40, which play key roles in NK cell development and immune response, exhibited differential binding activity between unstimulated and day 7 NK cells. Gene sets composed of target genes downstream of these transcription factors were also enriched at day 7, implying their involvement in NK cell activation. Moreover, we compared potential super-enhancer regions in NK cells before and after coculture, combined with the transcriptional activity of nearby genes. We identified stable and transcriptionally active super-enhancers in unstimulated and day 7 NK cells, as well as those that form or disappear after coculture initiation. The transcriptomic and epigenetic characterization of NK cells presented in this study could facilitate the ex vivo expansion and engineering of functionally superior NK cells.