Exploiting polypharmacology to dissect host kinases and kinase inhibitors that modulate endothelial barrier integrity.

Kinase inhibitors are promising drugs to stabilize the endothelial barrier following inflammatory damage. However, our limited knowledge of how kinase signaling activates barrier-restorative pathways and the complexity of multi-target drugs have hindered drug discovery and repurposing efforts. Here, we apply a kinase regression approach that exploits drug polypharmacology to investigate endothelial barrier regulation. A screen of 28 kinase inhibitors identified multiple inhibitors that promote endothelial barrier integrity and revealed divergent barrier phenotypes for BCR-ABL drugs. Target deconvolution predicted 50 barrier-regulating kinases from diverse kinase families. Using gene knockdowns, we identified kinases with a role in endothelial barrier regulation and dissected different mechanisms of action of barrier-protective kinase inhibitors. These results demonstrate the importance of polypharmacology in the endothelial barrier phenotype of kinase inhibitors and provide promising new leads for barrier-strengthening therapies.