Single-cell RNA sequencing reveals immune cell alterations in patients with allergic rhinitis treated with Peiyuan Tong-qiao decoction.

Allergic rhinitis (AR) is a chronic inflammatory disease with complex causes. Traditional Chinese medicine (TCM) shows promise for treating AR. This study aimed to explore the mechanisms behind TCM's effectiveness. In this study, we collected peripheral blood mononuclear cells (PBMCs) from AR patients before and after TCM treatment. Single-cell RNA sequencing (scRNA-seq) was performed to identify cell types and differentially expressed genes (DEGs) and analyzed immune cell pathways to understand how TCM treats AR. Cell-cell communication and regulatory networks were also investigated. Accordingly, 11 major cell types were annotated. The strength of the outgoing interaction between CD14+ monocytes and Central Memory CD4+ T cells and Transitional B cells decreased and in-creased, respectively. Transcription factors (TFs), VDR, and RUNX3 regulated the balance of Th1/Th2 cells to improve AR symptoms. This study confirms the therapeutic effect of Peiyuan Tongqiao Decoction on AR and provides insights into its mechanism of action.