Pacritinib inhibits nurse-like cell viability. (A, B) PBMC from CLL patients were treated with ruxolitinib (5 μM), fedratinib (5 μM), pacritinib (1 μM) or vehicle control (DMSO) and NLC identified by flow cytometry (gate shown in A). A representative example is shown. The number of NLC per high-power field (± 95% confidence interval) is shown in B (n=9). (C) NLC were generated from CLL patient PBMC and treated with ruxolitinib (5 μM), fedratinib (5 μM), pacritinib (1 μM) or vehicle control (DMSO). NLC were visualized by fluorescent microscopy 24 hours later after phalloidin and DAPI staining. (D) CLL cells were removed from NLC cultures and NLC treated with ruxolitinib (5 μM), fedratinib (5 μM), pacritinib (1 μM) or vehicle control (DMSO). NLC viability was determined 24 hours later by Annexin V and PI staining (representative example is shown, n=3)