Abstract
Allergic rhinitis (AR) is an inflammatory disease of the upper airway that primarily affects the nasal mucosa, with Th2 differentiation-driven inflammation as a key contributor. A bioinformatics analysis of dataset GSE52804 identified Six-transmembrane epithelial antigen of prostate 4 (STEAP4), a metalloreductase involved in inflammation regulation, as associated with AR progression, though its specific function remains unclear. Data obtained from nasal mucosal tissues from AR patients (n = 13) and an ovalbumin (OVA)-induced AR mouse model demonstrated a marked upregulation of STEAP4. Subsequent loss-of-function experiments revealed that STEAP4 knockdown reduced Th1/Th2 imbalance-mediated inflammation, alleviating allergic symptoms in OVA-treated mice. Further investigations involved the purification of naïve CD4(+) T cells from healthy murine splenocytes and their Th2 polarization. Consistently, STEAP4 knockdown inhibited Th2 differentiation and the production of Th2-related cytokines in vitro. Additionally, Guanine adenine thymine adenine sequence-binding protein 3 (GATA3), a transcription factor essential for Th2 differentiation, was predicted to bind to the STEAP4 promoter. CHIP-PCR and dual-luciferase assays confirmed the transcriptional regulation of STEAP4 by GATA3. More importantly, STEAP4 knockdown rescued the promoting effects of GATA3 overexpression on Th2 differentiation. In conclusion, STEAP4 functions downstream of GATA3 to promote AR development by promoting Th2 differentiation-mediated inflammation, suggesting its potential as a target for AR treatment.