T cells linked to psoriasis, eczema

Munich - Recently published study results suggest that distinct antigen-specific T-cell responses may play a role in the pathogenesis of psoriasis and atopic eczema, HealthDay News reports.

The study, conducted by researchers at Technische Universität and Helmholtz Center Munich and published in the July 21 issue of the New England Journal of Medicine, evaluated three patients with concomitant psoriasis and atopic eczema and five patients with psoriasis and allergic contact dermatitis. Eczema and psoriasis lesions were used to obtain punch biopsy specimens. Histologic examination was carried out, and the cytokine profile of T-cell lines was determined. In addition, secretions of interferon-gamma, interleukin-4, interleukin-17, and interleukin-22 levels were quantified using an enzyme-linked immunosorbent assay.

The researchers found that there was a reaction to an epicutaneous allergen challenge in sensitized patients with psoriasis, with clinically and histologically verified eczema lesions containing a large number of allergen-reactive T cells. The cytokine profile of T cells derived from psoriasis and atopic eczema lesions were different, with Th1 and Th17 cells being higher in the psoriasis lesions, and Th2 and Th22 cells higher in atopic eczema lesions. Psoriasis-derived T-cell lines had higher levels of interferon-gamma and interleukin-17 secretions, whereas interleukin-4 levels were higher in T cells from atopic eczema lesions in vitro.

“These findings support a causative role for T cells triggered by specific antigens in both psoriasis and atopic eczema,” the authors wrote.