Sympathetic Signals Promote Immunosuppressive Neutrophils in Lung Tumors

It has become recognized that the nervous system can significantly influence cancer prognosis. However, the pathophysiological mechanism underlying neural modulation of the tumor immune microenvironment remains incompletely understood. Here, we exploit the advanced 3D imaging technique to reveal the frequent presence of sympathetic inputs in human non-small-cell lung cancer. Also, this spatial engagement of sympathetic innervations similarly occurs in the mouse models of lung tumors. Of importance, the local ablation of sympathetic signals strongly suppresses cancer progression. We then identify a neutrophil subtype uniquely present within lung tumors, whose immunosuppressive features are directly promoted by the sympathetic neurotransmitter norepinephrine via the b2-adrenergic receptor (Adrb2). In addition, norepinephrine stimulates the specific type of tumor cells to recruit such immunosuppressive neutrophils. Accordingly, we show that the Adrb2 antagonist effectively potentiates the anti-PD-L1 immunotherapy. Together, these results have elucidated a critical aspect of sympathetic signals in designating the immune microenvironment of lung tumors.