Cutting Edge: EPHB2 Is a Coreceptor for Fungal Recognition and Phosphorylation of Syk in the Dectin-1 Signaling Pathway

Abstract

Invasive fungal infections have become a leading cause of death among immunocompromised patients, leading to around 1.5 million deaths per year globally. The molecular mechanisms by which hosts defend themselves against fungal infection remain largely unclear, which impedes the development of antifungal drugs and other treatment options. In this article, we show that the tyrosine kinase receptor EPH receptor B2 (EPHB2), together with dectin-1, recognizes β-glucan and activates downstream signaling pathways. Mechanistically, we found that EPHB2 is a kinase for Syk and is required for Syk phosphorylation and activation after dectin-1 ligand stimulation, whereas dectin-1 is critical for the recruitment of Syk. Ephb2-deficient mice are susceptible to Candida albicans–induced fungemia model, which also supports the role of EPHB2 in antifungal immunity. Overall, we provide evidence that EPHB2 is a coreceptor for the recognition of dectin-1 ligands and plays an essential role in antifungal immunity by phosphorylating Syk.