Objective To study 6 type Ⅰ interferon (IFN)-inducible genes (IFIT4, IFI44, Ly6e,OAS1, OAS2 and OAS3) in patients with lupus nephritis (LN) and analyze its correlated expression levels with disease activity and/or clinical manifestations. Methods Total RNA was obtained simultaneously from kidney tissues and peripheral blood cells of 12 patients with diffuse proliferative lupus nephritis and 10 normal controls. Moreover, peripheral blood cells were obtained from 119 LN patients and 35 normal controls. Total RNA was extracted and reversely transcribed into complementary DNA. Gene expression levels were measured by real-time polymerase chain reaction by comparing to a housekeeping gene, and IFN score was calculated. Disease activity was determined by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Results The 6 genes were highly expressed in diffuse proliferative lupus nephritis patients compared with normal controls. IFN scores were positively correlated with SLEDAI score, the concurrent presences of anti-double-stranded DNA (anti-dsDNA) antibodies (P<0.05) and hypocomplementemia (P<0.01). Conclusion The 6 IFN-inducible genes are highly expressed iri LN patients. IFN scores are elevated in active lupus nephritis patients, in patients with positive anti-ds-DNA antibody and hypocomplementemia. IFN scores may be a useful biomarker for lupus nephritis therapy.

Objective To explore the role of chemokines and ehemokine receptors in the etiopathog-enesis of diffuse proliferative lupus nephritis (LN). Methods ① Total RNA from the kidney tissues and peripheral blood cells of 12 patients with diffuse proliferative LN and 10 normal controls were prepared simultaneously and reverse transcribed into complementary DNA. Sybr green dye based real-time quantitative PCR method was used to compare the expression levels (indicated as-AACt value) of MCP-1, CCL19,CXCLg, CXCL10 and CCR2, CCR7, CXCR3. ② Immunofluoresceee labeling and immunohistochemical staining technique were used to observe the distribution of chemokines MCP-1, CCL19, CXCL9 and CXCL10 in normal and patients kidney tissues. Results The 4 chemokines genes (MCP-1, CCL19, CXCL9 and CXCL10) were consistently highly expressed in kidney tissues and peripheral blood ceils of diffuse proliferative LN patients compared with normal controls. The 2 chemokine receptors, CCR2 and CXCR3 were also overexpressed in peripheral blood cells of diffuse proliferative LN patients. There was nearly no expression of these 4 chemokine proteins in normal kidneys. But they were found in glomeruli of diffuse proliferative LN patients. Conclusion The expression of chemokines in the peripheral blood cells may be used as biomarkers for LN. Further study maybe lead to the development of specific drugs targeting at them for the treatment of systemic lupus erythematosus (SLE).