Dataset Information

Innate Type 2 Response to Aspergillus fumigatus in a Murine Model of Atopic Dermatitis-like Skin Inflammation.

ABSTRACT:

Background

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease mediated by T helper type 2 (Th2) cells in acute phase. Group 2 innate lymphoid cells (ILCs) play a role in the initiation of the Th2 response. Although mold exposure is associated with the development of AD, studies on the underlying mechanisms are lacking. This study investigated whether group 2 ILCs are involved in inflammation in AD-like skin induced by Aspergillus fumigatus (Af).

Methods

We investigated changes of group 2 ILCs population in Af-induced AD-like skin lesions. To induce AD-like skin lesions, Af extracts were applied to the dorsal skin of BALB/c and Rag1^-/- mice five times per week, with repeat exposures at 2-week intervals.

Results

The clinical parameters were higher in the Af-treated group than in the control group. Histologic findings revealed epiderrmal and dermal thickening as well as eosinophil and mast cell infiltration into the skin of Af-treated mice. Populations of group 2 ILCs in the skin were also significantly higher in the Af-treated group. In addition, interleukin-33 mRNA expression was significantly higher in the skin lesions of the Af-treated mice. In the Rag1^-/- mice lacking mature lymphocytes, AD-like skin lesions were still induced by Af and ILCs depletion using an anti-CD90.2 mAb lowered the Af-induced inflammatory response.

Conclusions

Group 2 ILCs may play a role in a murine model of Af-induced AD-like skin lesions.

SUBMITTER: Park A

PROVIDER: S-EPMC8524237 | biostudies-literature |

REPOSITORIES: biostudies-literature

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