SAT0180 B7-H4 expression of renal tubular epithelial cells in patients with lupus nephritis

Background B7-H4 is a newly identified B7 family negative co-stimulate molecule, the expression and function of B7-H4, in the pathogenesis of lupus nephritis (LN) is still unclear. Objectives To investigate the expression of B7-H4 in patients with LN and the function of renal tubular epithelial cells (TECs)-associated B7-H4 in the regulation of T cell activation in vitro. Methods 90 LN patients, 3 acute kidney injury patients and 20 healthy donors were referred. Disease activity was assessed by SLEDAI scores. The expression of B7-H4 on kidney biopsies from patients with LN and acute kidney injury was measured using immunohistochemistry. In vitro, B7-H4 antigen on cultured HK-2 cells with or without stimulation by inflammatory factors was detected by flow cytometry. After co-cultured with HK-2 and purified CD4+T cells labeled with CFSE for 72 hours, T cell proliferation was detected by flow cytometry. The soluble B7-H4 in sera of LN patients and healthy donors were analyzed using ELISA. Results B7-H4 antigen expressed on tubular epithelium, the percentage of B7-H4 positive expression renal tubules from LN patients (45±16) % was lower than acute kidney injury patients (86±11) % (P Conclusions B7-H4 molecules may play a role in the progress of LN, a clear understanding of its functional roles may further elucidate the pathogenesis of this disease. Disclosure of Interest None Declared