NFATc1 deficiency in B cells ameliorates atopic dermatitis.

Atopic dermatitis (AD) is a common skin allergy, affecting large population worldwide. Currently, there is no cure for AD. NFATc1, a transcription factor, operates through a calcium-dependent calcineurin/calmodulin pathway to regulate target genes and is vital in immune system development and function. Previous research suggests that NFATc1 suppresses IL-10 in B cells by binding to its gene. Our current study explores the role of B cells deficient of NFATc1 during calcipotriol, a vitamin D analog, induced AD responses. Our data showed that Nfatc1 x mb1cre AD mice exhibited a diminished AD phenotype compared with WT AD mice, by reduced ear swelling, lower epidermal thickening, and fewer cellular infiltration to ear. This was evident by unaltered IgE levels. Interestingly, Nfatc1xmb1cre AD mice displayed a higher percentage of IL-10-producing B220CD5CD1d Breg cells, indicating that NFATc1 deficiency promotes the differentiation of B cells into Bregs that produce more anti-inflammatory IL-10, thus alleviating AD symptoms. At the transcriptome level, NFATc1 deficient B cells bearing AD mice exhibited distinct gene expression profiles compared with WT AD mice, with genes that promoted B-cell development and enhanced stress and stimulus responses. This study highlights the potential of targeting NFATc1 as a molecular strategy to reduce AD symptoms without impairing B-cell function while boosting the production of the endogenous anti-inflammatory IL-10.