The effect of treatment with fexofenadine and fluticasone propionate on the gene expression levels of Th9 transcription factors in patients with allergic rhinitis

T helper-9 (Th9) is a new T cell subset involved in allergic rhinitis (AR) pathogenesis. Fexofenadine and fluticasone propionate are the first effective line of AR treatment. This study aimed to evaluate the effect of fexofenadine and fluticasone propionate on the gene expression levels of Interferon regulatory factor 4 (IRF4), B cell-activating transcription factor-like (BATF), and SPI1 gene-encoded protein (PU.1), essential transcription factors for Th9 cell differentiation, in AR patients. Twenty-six AR patients (aged 32.8 ± 9.1 years, 13 men and 13 women) were treated with fexofenadine and fluticasone propionate for one month. Expression levels of PU.1, IRF4, and BATF genes were measured using Real-Time PCR. Our results showed that after one month of treatment, the expression level of IRF4 and BATF genes decreased significantly (P < 0.001, P < 0.01, respectively), while PU.1 gene expression was not remarkably different. Overall, our results showed that after one month of treatment with fexofenadine and fluticasone propionate, the expression levels of IRF4 and BATF genes in AR patients decreased, which may be due to this treatment regimen. However, the exact mechanism of action of fexofenadine and fluticasone propionate needs further study.