CRISPRi screening reveals genetic determinants of surface CD38 regulation. (A) Schematic of CRISPRi screen design. (B) Results of CRISPRi screen demonstrating genes that, when knocked down, regulate surface CD38 in RPMI-8226 cells. The x-axis indicates phenotype (epsilon) from MAGeCK³¹ statistical analysis. Dashed line indicates cutoff for significant change at false discovery rate (FDR) <0.05. Genes of interest are specifically labeled. 4000 negative control nontargeting sgRNAs are in gray. (C) Gene ontology (GO) Biological Process and KEGG analysis of all genes that when knocked down lead to significant CD38 upregulation. (D) Follow-up flow cytometry validation of CRISPRi screen hits using 2 individual sgRNAs per gene demonstrates TLE3 knockdown drives increased CD38, whereas SPI1 knockdown leads to CD38 decrease.