Human 6-sulfo LacNAc (slan) dendritic cells are a major population of dermal dendritic cells in steady state and inflammation.

BACKGROUND: The immune system of the skin has a network of resident dendritic cells (DCs) consisting of epidermal Langerhans cells and various subsets of dermal DCs. We recently reported on a new population of dermal DCs, called slan (6-sulfoLacNAc+) DCs, which have a potent capacity to stimulate Th17/Th1 T-cell responses. AIM: To understand the characteristics of slanDCs as a new population of dermal DCs in the context of other DC populations in healthy and psoriatic skin.
METHODS: We immunofluorescently stained skin samples from healthy controls and from patients with psoriasis.
RESULTS: Staining healthy skin for DCs showed that slanDCs (CD1a- CD1c- CD11c- CD14- CD163-) were present at a similar frequency to that of CD1c+ CD11c+ CD1a+ CD14- CD163- dermal DCs, which have previously been regarded as the major population of resident DCs. In psoriatic skin, the frequency of slanDCs and CD1c+ DCs was doubled, and the slanDCs expressed CD11c. In-depth analysis of DCs in psoriatic skin by four-colour immunofluorescence analysis showed that the pool of CD11c+ cells could be further subdivided into CD11c+ CD14+ CD163- DCs and CD11c+ CD163+ CD14+ macrophages.
CONCLUSION: SlanDCs, initially described as large population of proinflammatory DCs in blood, are a novel and major part of the resident dermal myeloid DC system in both healthy and inflamed skin. © The Author(s). CED