Ficolin 1 Expression is Elevated in the Peripheral Blood Mononuclear Cells of Takayasu's Vasculitis Patients

Takayasu’s arteritis (TA), a form of vasculitis (angiitis), is a chronic inflammatory disease involving the large blood vessels. This study reports the identification of genes showing increased mRNA levels in peripheral blood mononuclear cells (PBMCs) from TA patients regardless of symptoms or disease activity/inactivity. Of these, mRNA for Ficolin 1 (FCN1) showed a four-fold increase in all eight TA patients examined. Increased FCN1 mRNA levels observed in cDNA microarrays were confirmed by quantitative reverse transcription polymerase chain reaction. Increased FCN1 protein expression was also observed in inflamed regions of the surgical aorta specimens. Moreover, most FCN1-positive cells were also positive for CD68, indicating the presence of monocytic cells, such as macrophages or dendritic cells, which attack infectious agents within the inflamed regions. Taken together, the results suggest that FCN1 mRNA levels in peripheral blood samples may be a diagnostic marker for TA.