Fig 1: Establishing an in vitro cancer-NK model for CRISPR screens.(a) Western blot of Cas9 protein from WT and Cas9 transduced whole cell lysates. Alpha tubulin measured as a loading control. (b) Representative flow cytometric analysis gated on GFP expression to measure Cas9 efficiency using pMCB306 plasmid. Loss of GFP denotes Cas9 activity (Methods). (c) Western blot of beta-2-microglobulin (B2M) from whole cell lysates of WT, Cas9, and B2MKO TYK-nu. GAPDH measured as a loading control. (d) B2M surface expression by flow cytometry in B2Mwt and B2MKO Cas9 TYK-nu cells. (e) 24-to-72-hour time course cell viability in co-cultures of TYK-nuCas9 and NK-92 cells at variable effector to target cell ratios. Percent killing was calculated by normalizing to monoculture conditions. Co-cultures were performed in 4 replicates per condition as shown. (f) 48-hour cell viability of B2MKO and B2MWT TYK-nu cell lines in co-culture with NK-92 cells. Percent killing was calculated by normalizing to the respective monoculture conditions. Data shown in (a) and (c) are one representative experiment repeated two or more times with similar results. In (e) and (f), co-culture data is represented by mean ± s.e.m. for (e) and mean ± standard deviation for (f) with each experiment performed in n = 4 technical replicates; p-values **** represent p < 1 × 10−4 and *p < 0.05 (two-way analysis of variance (ANOVA) with multiple comparisons); ‘ns’ shown denote non-significant (p > 0.05) comparisons. Exact p-values and raw blot images are provided with the Source Data. All statistical tests were conducted on GraphPad Prism version 10.2.3. Source data