The Biology of Plasmacytoid Dendritic Cells and their Role in Pathogenesis of Erythema Multiforme and Other Inflammatory Dermatoses: A Mini Literature Review

Plasmacytoid Dendritic Cells (pDCs) are a unique dendritic cell population with both innate and adaptive immune functions. When pDCs get activated by various pathogens or self-DNA, they are able to produce massive amount of interferon type I and play an essential role in immune defense mechanisms. Plasmacytoid DCs are generally absent from the normal skin. In the past decade, their involvement in pathogenesis of different inflammatory dermatoses has been widely explored. Plasmacytoid DCs’ excessive sensing of non-self or self-DNA (upon skin injury) was addressed as a primary trigger for many cutaneous pathologies. Recently, we have also shown significant amount of pDCs in erythema multiforme lesions and hypothesized that these cells are central to EM pathogenesis as well. However, neither EM pathogenesis nor pDCs’ actual role in this entity is well studied. In this mini review, our goal is to outline recent updates on pDCs and their role in particular inflammatory skin diseases such as psoriasis. Our focus will also be the highlights of our recent study and our perspective regarding relationship between pDCs and EM.