Flow analysis of MHC-I surface levels following DUX4 knockdown in SuSa cells

Gapmer-mediated knockdown of DUX4 to assay causal effect on population of SuSa cells with MHC-I low surface presentation levels.
Conclusion:
Knockdown of endogenous DUX4 in SuSa cells rescued 5% of the MHC-I low population relative to control, corresponding with the percentage of cells that expressed a brief pulse of DUX4 as evidenced by prolonged expression of DUX4 targets H3.X/Y. These results demonstrated that endogenous DUX4 expression in SuSa germinoma cells suppressed IFNg-induced MHC-I expression.
Notes:
SuSa cells were synchronized and released from confluence, lifted using trypsin, seeded onto gelatin-coated plates, and reverse transfected with either a pool of two DUX4-targeting gapmers or a non-targeting control gapmer. Cells were treated with or without IFNγ for the last 16 hours and harvested at 72 hours post-release. Cells were stained with BV605 anti-human HLA-A,B,C Antibody (BioLegend #311432), resuspended in FACS buffer (1xDPBS, 1% BSA, 5mM EDTA), and analyzed using BD LSRFortessa X-50 paired with BD FACSDiva software. Data were analyzed using FlowJo V10.5.3.