Chemerin as a colocalization signal for CD123⁺/BDCA-2⁺ plasmacytoid DCs, DC-SIGN⁺ myeloid DCs, and NK cells in OLP. In OLP, CD123⁺/BDCA-2⁺ plasmacytoid DCs and DC-SIGN⁺ DCs are present in the inflammatory infiltrate and within the epithelium. The vast majority of CD123⁺ plasmacytoid DCs and a proportion of DC-SIGN⁺ DCs coexpress ChemR23⁺ cells. Close cell-to-cell contacts (white arrowheads) can be observed between BDCA-2⁺ plasmacytoid DCs and CD56⁺ NK cells as well as DC-SIGN⁺ DCs and CD56⁺ NK cells. Epithelial and inflammatory cells in oral lichen planus express MxA, as opposed to oral mucosal biopsies from patients showing reactive acanthosis (inset), which is completely negative. In the same sections, chemerin is expressed on the luminal side of the endothelial cells (black arrows and inset). In addition scattered chemerin-positive cells with epithelial morphology are detectable in the epithelium (black arrowheads). Original magnifications are all × 400, except top row (× 100) and MxA (× 200) and insets: MxA (× 50) and chemerin (× 300).