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 IRF4, IRF8, SP1, and PU.1 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, IRF4 expression increased significantly in SLE patients, unlike at baseline, where no changes were observed between groups. IRF8 expression was significantly raised in active SLE and increased upon activation. SP1 expression remained stable across all groups and conditions. PU.1 gene expression was higher in active SLE at baseline and increased further upon B cell activation. Positive correlations were found between IRF4 and IRF8, as well as between PU.1 and SP1. PU.1 expression correlated with SLE disease activity indices.ConclusionIRF4, IRF8, and PU.1 expression in B cells is altered in SLE. PU.1 shows a positive correlation with SLEDAI and anti-dsDNA titers. These findings highlight their potential roles in the pathogenesis of SLE in B cells.