摘要
Plasmacytoid dendritic cells(pDCs),also known as type I interferon(IFN)-producing cells,are specialized immune cells characterized by their extraordinary capabilities of mounting rapid and massive type I IFN response to nu-cleic acids derived from virus,bacteria or dead cells.PDCs selectively express endosomal Toll-like receptor(TLR)7 and TLR9,which sense viral RNA and DNA re-spectively.Following type I IFN and cytokine responses,pDCs differentiate into antigen presenting cells and ac-quire the ability to regulate T cell-mediated adaptive immunity.The functions of pDCs have been implicated not only in antiviral innate immunity but also in immune tolerance,inflammation and tumor microenvironments.In this review,we will focus on TLR7/9 signaling and their regulation by pDC-specific receptors.