TLR7 and psoriasis: Notably, CXXC5 is highly expressed in plasmacytoid dendritic cells (pDCs) and is crucial for robust interferon responses to TLR7/9 stimulation (pDCs are one of the initiating immune cell types in psoriasis, as self-DNA/RNA induced pDC activation has been implicated in psoriatic plaque development) (Ma et al., 2017).