Increased frequencies of basophils, type 2 innate lymphoid cells and Th2 cells in skin of patients with atopic dermatitis but not psoriasis

J Dermatol Sci. 2017 Nov;88(2):167-174. doi: 10.1016/j.jdermsci.2017.07.003. Epub 2017 Jul 15.


Background: Pathogenesis of atopic dermatitis (AD) involves interaction between type 2 cells that include basophils, mast cells, innate lymphoid type 2 cells (ILC2), and Th2 cells. Levels of IL-4 and IL-13 are elevated in AD patients.

Objective: Here, we investigated the distribution of type 2 cells and the source of IL-4 and IL-13 in skin and blood of AD relative to psoriasis.

Methods: Lesional skin biopsies and blood were collected from patients. Skin cell suspensions were prepared by mild enzymatic digestion and mechanical dissociation. IL-4 and IL-13 expression was analyzed at single-cell level before or after stimulation using flow cytometry.

Results: Frequencies of basophils, ILC2 and Th2 but not mast cells were significantly elevated in skin, and not blood, of AD relative to psoriasis. IL-4 production by circulating basophils and Th2 cells, and IL-13 by ILCs and Th2 cells was similar in both diseases. In contrast, skin T cells expressed IL-4 and IL-13 prior to stimulation in AD when compared to psoriasis. Moreover, skin basophils, which were detected in AD only, expressed IL-4 following stimulation. Interestingly, basophils and ILC2 were positively correlated in skin, whereas skin basophils were inversely correlated with blood ILC2.

Conclusions: Lesional AD skin harbors a distinctive innate and adaptive type 2 profile, which is characterized by basophils producing IL-4, Th2 cells expressing IL-4 or IL-13, and ILC2. This underlies the therapeutic efficacy of targeting IL-4 and IL-13 signaling pathways in AD.

Keywords: AD; Basophils; ILC2; Psoriasis; Skin; Th2.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Basophils / immunology*
  • Basophils / metabolism
  • Biopsy
  • Dermatitis, Atopic / blood
  • Dermatitis, Atopic / immunology*
  • Dermatitis, Atopic / pathology
  • Female
  • Flow Cytometry
  • Humans
  • Immunity, Innate*
  • Interleukin-13 / metabolism
  • Interleukin-4 / metabolism
  • Male
  • Middle Aged
  • Psoriasis / blood
  • Psoriasis / immunology*
  • Psoriasis / pathology
  • Signal Transduction
  • Skin / cytology
  • Skin / immunology*
  • Skin / pathology
  • Th2 Cells / immunology*
  • Th2 Cells / metabolism
  • Young Adult


  • IL4 protein, human
  • Interleukin-13
  • Interleukin-4