Allergen sensitization – insights into atopic dermatitis and other skin disorders


Interleukin (IL)-31 is a neuroimmune cytokine which is involved in the pathophysiology of atopic dermatitis through the maintainnance of an inflammatory state and pruritus (Figure 1).

Figure 1: HDM-induced IL-31 by memory T cells correlates with patient’s pruritus and plasma CCL27 and periostin, partially depends on HLA class II molecules and the cell-cell contact with epidermal cells, and is restricted to CLA+ T-cells subset. (A) IL-31 (pg/mL) produced by CLA+/- T-cell cocultures in basal conditions (M) or stimulated with HDM in AD-(n=58) and C-(n=11) derived samples. Correlations of CLA+/Epi/HDM IL-31 production in group 1 with (B) pruritus (n=17), and plasma (C) CCL27 (n=17) and (D) periostin (n=13) levels. (E) Correlation between plasma CCL27 levels and SCORAD in group 1 (n=15) and group 2 (n=31) of patients. (F) HDM-activated CLA+/- T-cell cocultures were treated with HLA class II neutralizing antibody or control IgG isotype at day 0, and IL-31 production (pg/mL) at day 5 was compared with respect to isotype values (n=6). Red bar indicates the mean. (G) CLA+/- T cells were added in the upper chamber and HDM-stimulated epidermal cells suspension in the lower chamber of the 96-well transwell plate and IL-31 (pg/mL) was measured at day 5. Data for three representative patients. AD, atopic dermatitis; C, control subjects; CLA, cutaneous lymphocyte-associated antigen T cells; Epi, epidermal cells suspension; HDM, house dust mite; M, untreated; SCORAD, scoring atopic dermatitis. ns: p >.05; *p <.05; **p <.01; ****p <.0001.

Lidia Sans-de San Nicolàs, et al., studied IL-31 production by memory cells following cell culture, cytokine quantification and gene analysis. The authors investigated IL-31 production by memory T cells cultured with  autologous lesional epidermal atopic dermatitis cells under HDM stimulation. Two groups were defined – group 1, where IL-31 was produced by CLA+ cells and group 2, without IL-31 production. A higher inflammatory phenotype was observed in group 1 when compared to group 2.

In group 1, a correlation was found between IL-31 production and HDM specific IgE and total IgE. Furthermore IL-31 production by memory T cells was found to be associated with higher levels of IL-4, IL-5, IL-13, IL-22, IL-17A with equal expression to IL-13. Between the two groups of patients, an increased level of IgE specific to HDM was found in group 1.

To further characterize group 1 and 2, the authors evaluated changes in lesional skin tissue from patients using gene array analysis finding that in group 1, IL-17 and IL-21 mRNA expression was higher. Finally, high levels of IgE was observed in patients with IL-31 production by memory T cells, specific to the CLA+ subset.

From these results, the authors could hypothesise about an correlation between IL-31, periostin and CCL27 which act like a chemokine to CLA+ T cells. In addition, they described limited production of IL-31 by T cells to CLA+ cells subset which reflect specific mechanisms taking place in A.D and others cutaneous diseases.

Journal article: Sans-de San Nicolàs, L., et al., 2023. Allergen sensitization stratifies IL-31 production by memory T cells in atopic dermatitis patients. Frontiers in Immunology.

Summary by Frederic Christian Diaz

International Union of Immunological SocietiesUniversity of South AfricaInstitute of Infectious Disease and Molecular MedicineElizabeth Glazer Pediatric Aids Foundation