Overexpression of IRF8 and Pu.1 in B cells of systemic lupus erythematosus patients

BackgroundSystemic Lupus Erythematosus (SLE), a complex autoimmune disorder characterized by altered immune regulation, particularly involving B cells, which exhibit increased survival and developmental dysregulation. This study aimed to investigate the expression of IRF4, IRF8, SP1, and PU.1 in B cells of SLE patients, as these factors are known to play critical roles in the development, function, and differentiation of B cells.MethodsB cells were isolated, cultured, and activated using anti-IgM. The mRNA expression of <i>IRF4</i>, <i>IRF8</i>, <i>SP1</i>, and <i>PU</i>.<i>1</i> was assessed using reverse transcription polymerase chain reaction (RT-PCR) at baseline and after B cell activation. Correlations between transcription factor expression and clinical parameters were analyzed.ResultsUpon B cell activation, <i>IRF4</i> expression increased significantly in SLE patients, unlike at baseline, where no changes were observed between groups. <i>IRF8</i> expression was significantly raised in active SLE and increased upon activation. <i>SP1</i> expression remained stable across all groups and conditions. <i>PU</i>.<i>1</i> gene expression was higher in active SLE at baseline and increased further upon B cell activation. Positive correlations were found between <i>IRF4</i> and <i>IRF8</i>, as well as between <i>PU</i>.<i>1</i> and <i>SP1</i>. <i>PU</i>.<i>1</i> expression correlated with SLE disease activity indices.Conclusion<i>IRF4</i>, <i>IRF8</i>, and <i>PU</i>.<i>1</i> expression in B cells is altered in SLE. <i>PU</i>.<i>1</i> shows a positive correlation with SLEDAI and anti-dsDNA titers. These findings highlight their potential roles in the pathogenesis of SLE in B cells.