Fig. 1.

Simplistic representation of skin and gut interconnection in health and during psoriasis. The diseased state is characterized by a disturbed barrier function of the skin and gut. In psoriatic skin, this is usually associated with perturbed composition of microbiota, increased production of antimicrobial peptides, increased transepidermal water loss, and overall inflammation, which manifests as skin redness, thickening, and accelerated cell turnover in psoriatic lesions. In the gut of patients with psoriasis, the diseased state is usually associated with microbiota dysbiosis, lower production of SCFAs, disrupted mucus layer, increased intestinal permeability, or decreased IgA secretion. DC dendritic cells, pDC plasmacytoid dendritic cell, SCFAs short-chain fatty acids