Activation of the JAK/STAT pathway in Behcet’s Disease

Th1/Th17-type T-cell responses are upregulated in Behcet’s disease (BD). However, signaling pathways associated with this aberrant immune response are not clarified. Whole-genome microarray profiling was performed with human U133 (Plus 2.0) chips using mRNA of isolated CD14+ monocytes and CD4+ T-cells from PBMC in patients with BD (n=9) and healthy controls (HC) (n=9). Flow cytometric analysis of unstimulated (US) and stimulated (PHA) STAT3 and pSTAT3 expressions of PBMCs were also analysed (BD and HC, both n=26). JAK1 was observed to be upregulated in both CD14+ monocytes (1.94 fold) and CD4+ T-lymphocytes (1.40 fold) of BD patients. Using canonical pathway enrichment analysis, JAK/STAT signaling was identified as activated in both CD14+ monocytes (p=2.95E-06) and in CD4+ lymphocytes (p=8.13E-04) in BD. Interferon (p=1.02E-07) and IL-6 (p=8.91E-03) signaling pathways were also prominent in CD14+ monocytes. Basal unstimulated total STAT3 expression was significantly higher in BD (1.2 vs 3.45, p<0.05). The JAK1/STAT3 signaling pathway is activated in BD, possibly through the activation of Th1/Th17-type cytokines such as IL-2, IFNγ, IL-6, IL-17 and IL-23. Gene expression profile from two cell types sorted from PBMCs: CD4+ and CD14+. CD4+ profiling has 3 controls and 9 patients samples, CD14+ has 9 controls and 8 patients samples.