Alopecia Areata: A Review of Disease Pathogenesis

F. Rajabi; L.A. Drake; M.M. Senna; N. Rezaei


The British Journal of Dermatology. 2018;179(5):1033-1048. 

In This Article

The Role of Plasmacytoid Dendritic Cells

Two distinct groups of dendritic cells exist: plasmacytoid dendritic cells (PDCs) and myeloid dendritic cells (MDCs).[178,179] MDCs are antigen-presenting cells residing in normal skin. PDCs are normally found in lymphoid tissues and possesses both antigen-presenting and innate immune markers.[180] In a pathological state PDCs are recruited to the skin, and upon activation via Toll-like receptors they produce large amounts of type 1 IFN (IFN–α and β). PDCs are the pioneer cells involved in psoriasis, atopic dermatitis and lupus erythematosus.[181–184] Association of AA with lupus and psoriasis,[185–187] presence of PDCs in the peribulbar region of HFs,[188] the strong IFN–α signature of AA lesions[189,190] and the capability of IFN–α in disease induction[191,192] are all in favour of the preliminary role of PDCs in AA.