Abstract
BACKGROUND: Chronic inflammatory disease is responsible for huge and increasing global mortality and morbidity. Unregulated inflammatory cells, including neutrophils and macrophages, are major drivers of chronic inflammatory disease. Efferocytosis plays a critical role in inflammation resolution by removing effete inflammatory cells from tissues. Despite defective efferocytosis being critical in inflammatory disease progression there are no therapies to correct these defects in clinical use. Here, using experimental models of atherosclerosis and lung injury, we identify the ErbB family tyrosine kinase inhibitor (TKI), neratinib, as a putative efferocytosis-targeting therapy. RESULTS: In an experimental model of atherosclerosis and lung injury, two doses of neratinib significantly increased efferocytosis in the lungs of mice concomitant with a reduction in the proportion of lung neutrophils. Neratinib significantly increased human neutrophil apoptosis and efferocytosis of apoptotic neutrophils by monocyte-derived macrophages (MDMs). In addition to increased efferocytosis, neratinib treated macrophages demonstrated both increased phagocytosis and macropinocytosis. Neratinib increased MDM surface expression of the efferocytosis receptor MerTK independent of protein synthesis and transcription which correlated with elevated efferocytosis in MDMs and inhibitors of MerTK blocked neratinib-induced efferocytosis. CONCLUSIONS: Thus, we describe a novel role for neratinib in driving efferocytosis in multimorbidity and suggest that ErbB TKIs may have therapeutic potential in inflammatory disease by restoring macrophage function and promoting inflammation resolution.