PN lesions contain a number of immune cells, including type 2 cells1-8:



Th2 cells, Th17 cells,
and Th22 cells



Mast cells


Increased activity of type 2 cytokines IL-4, IL-13, and IL-31, as well as other inflammatory mediators (IL-17, IL-22, pruritogens, and neuropeptides), is present in PN skin4,5,9,10




Signaling of type 2 cytokines, including IL-4 and IL-13, may contribute to signs and symptoms of PN


    IL-4, IL-13, and IL-31 potential effects on itch

  Sensitization of nerves to pruritogens11,a


  Upregulation of the receptor for IL-3112,13

   IL-4, IL-13, and IL-31 potential effects on skin

   Increased fibroblast proliferation and collagen production,periostin expression and stimulating profibrotic cytokine TGF-β production may influence skin remodeling and nodule formation11,12

  Skin barrier dysfunction: inhibition of keratinocyte differentiation and altered lipid synthesis13

  Epidermal differentiation, inflammatory responses, and extracellular remodeling14


The skin, immune system, and nervous system have a dysregulated relationship in PN15-19

Increased activity of type 2 immune cells and cytokines, along with certain other immune cells and inflammatory mediators, may contribute to signs and symptoms of PN through interactions with neurons and other dermal and epidermal resident cells1-10,20-23

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    13. Hashimoto T, Nattkemper LA, Kim HS, et al. Dermal periostin: a new player in itch of prurigo nodularis. Acta Derm Venereol. 2021;101(1):adv00375.
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    20. Campion M, Smith L, Gatault S, Métais C, Buddenkotte J, Seinhoff M. Interleukin-4 and interleukin-13 evoke scratching behaviour in mice. Exp Dermatol. 2019;28(12):1501-1504.
    21. Edukulla R, Singh B, Jegga AG, Sontake V, Dillon S, Madala S. Th2 cytokines augment IL-31/IL-31RA interactions via STAT6-dependent IL-31RA expression. J Biol Chem. 2015;290(21):13510-13520.
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MAT-BH-2200541/V1/June 2022