抗リボソームＰ抗体はヒト単球系白血病細胞株THP-1からのVEGF産生を亢進する

抄録

    Autoantibodies to ribosomal P proteins (anti-P) are detected in 12-16% of patients with systemic lupus erythematosus (SLE), and have been found to be associated with neuropsychiatric manifestations of the disease. Moreover, recent studies have disclosed the association of anti-P with hepatitis and nephritis in SLE. The presence of an epitope that is antigenically related to the carboxyl terminus of ribosomal P proteins has been demonstrated on the surface of human hepatoma cells, neuroblastoma cells, and endothelial cells. Recent studies have shown that anti-P reacts with activated T cells, but not with B cells. However, the presence of the epitope recognized by anti-P on human monocytic cell lines has not been elucidated. In the current studies, we used affinity-purified IgG from anti-P positive lupus patients to explore whether anti-P reacts with human monocytic cell line THP-1 cells. Flow cytometry analysis demonstrated that THP-1 cells constitutively expressed the ribosomal P epitope. Of note, anti-P enhanced the production of vascular endothelial growth factor (VEGF) of THP-1 cells in a dose response manner. These results suggest that anti-P might promote vascular permeability and facilitate the entry of immunocompetent cells into the site of inflammation, including the central nervous system, through the induction of vascular endothelial growth factor on activated monocytelineage cells.