Upregulated Expression of Runt-related Transcription Factor 3 and Interferon Regulatory Factor 4 Genes in Patients With Ankylosing Spondylitis

Background: Ankylosing spondylitis (AS) is a debilitating autoimmune disease presented by chronic inflammation of large joints and central skeleton. The role of various immune cells, including T cell subsets, has been studied in the pathogenesis of AS. Two critical transcription factors, runtrelated transcription factor 3 (RUNX3) and interferon regulatory factor 4 (IRF4), are involved in the differentiation and function of T lymphocytes. This study compared the gene expression level ofRUNX3 and IRF4 between patients with AS and healthy subjects to understand the impact of these factors in the immunopathogenesis of the disease. Methods: Thirty patients with AS and 30 age- and gender-matched healthy individuals were recruited to the study, and expression of RUNX3 and IRF4 genes was evaluated using the reverse transcription polymerase chain reaction (RT-PCR) technique in their peripheral blood. Results: The expression of RUNX3 and IRF4 genes in AS patients was significantly upregulated compared to the healthy controls (P=0.03 and 0.025, respectively). In addition, there was a direct correlation between IRF4 gene expression and bath ankylosing spondylitis global score (BAS-G) (correlation coefficient=0.38, P=0.04). Conclusion: Gene expression of RUNX3 and IRF4 transcription factors involved in T cells’ differentiation and function was increased in AS. These findings might have prognostic and therapeutic value.