García-Jiménez, IreneSans-de San Nicolás, LídiaCurto-Barredo, LaiaBertolín-Colilla, MartaSensada-López, EloiFigueras Nart, IgnasiBonfill-Ortí, MontserratGuilabert-Vidal, AntonioRyzhkova, AnnaFerran, MartaDamiani, GiovanniCzarnowicki, TaliPujol Vallverdú, Ramón M.Santamaria Babí, Luis F.2025-02-142025-02-142024-08-061661-6596https://hdl.handle.net/2445/218796Interleukin (IL)-9 is present in atopic dermatitis (AD) lesions and is considered to be mainly produced by skin-homing T cells expressing the cutaneous lymphocyte-associated antigen (CLA). However, its induction by AD-associated triggers remains unexplored. Circulating skin-tropic CLA+ and extracutaneous/systemic CLA− memory T cells cocultured with autologous lesional epidermal cells from AD patients were activated with house dust mite (HDM) and staphylococcal enterotoxin B (SEB). Levels of AD-related mediators in response to both stimuli were measured in supernatants, and the cytokine response was associated with different clinical characteristics. Both HDM and SEB triggered heterogeneous IL-9 production by CLA+ and CLA− T cells in a clinically homogenous group of AD patients, which enabled patient stratification into IL-9 producers and non-producers, with the former group exhibiting heightened HDM-specific and total IgE levels. Upon allergen exposure, IL-9 production depended on the contribution of epidermal cells and class II-mediated presentation; it was the greatest cytokine produced and correlated with HDM-specific IgE levels, whereas SEB mildly induced its release. This study demonstrates that both skin-tropic and extracutaneous memory T cells produce IL-9 and suggests that the degree of allergen sensitization reflects the varied IL-9 responses in vitro, which may allow for patient stratification in a clinically homogenous population.14 p.application/pdfengcc-by (c) García-Jiménez,I et al., 2024http://creativecommons.org/licenses/by/4.0/Cèl·lules TDermatitis atòpicaInterleucinesT cellsAtopic dermatitisInterleukinsinfo:eu-repo/semantics/article7549222025-02-14info:eu-repo/semantics/openAccess