Wnt pathway regulates IL-34 level in lupus nephritis.

OBJECTIVE: The aim of this study was to investigate the role of the Wnt pathway in regulating the IL-34 level of lupus nephritis (LN) patients, and to explore the underlying mechanism. MATERIALS AND METHODS: Human mesangial cells (HMCs) of LN patients were selected. The expression level of IL-34 was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot, respectively. Subsequently, HMCs were treated with the Wnt pathway antagonist, DDK1. Meanwhile, the IL-34 level in DDK1 transfected HMCs was then detected. In addition, the viability of HMCs treated with DDK1 was detected by cell counting kit-8 (CCK-8) and colony formation assay, respectively. RESULTS: Both the mRNA and protein levels of IL-34 were significantly upregulated in HMCs of LN patients. Higher expression of ß-catenin was observed in HMCs of LN patients than those of controls, which was reduced after DDK1 treatment. Meanwhile, IL-34 level in HMCs of LN patients was significantly downregulated after DDK1 treatment. In addition, DDK1 treatment remarkably increased the proliferative ability and colony formation ability of HMCs in LN patients. CONCLUSIONS: IL-34 is highly expressed in HMCs of LN patients and is negatively regulated by the Wnt pathway. Furthermore, HMCs viability is remarkably enhanced after blocking the Wnt pathway.

Correlation analysis of TLR9 and IL-23 expression in patients with lupus nephritis.

OBJECTIVE: The aim of this study was to investigate the expression levels of toll-like receptor 9 (TLR9) and interleukin-23 (IL-23) in renal tissue and serum of patients with lupus nephritis (LN), and to explore their clinical correlation. PATIENTS AND METHODS: LN patients and healthy controls were enrolled in the experimental group and the control group, respectively. Blood samples, serum, and peripheral blood mononuclear cells (PBMCs) were collected. Renal lesion tissues and adjacent normal tissues of LN patients were harvested from a renal tissue biopsy. Serum level of IL-23 was detected by enzyme-linked immunosorbent assay (ELISA). Expression of IL-23 in PBMCs was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot, respectively. Meanwhile, TLR9 expression in renal tissues was accessed by immunohistochemistry staining. Subsequently, 24-h protein urine, renal tubular pathological activity index, erythrocyte sedimentation rate (ESR), serum complement C3 level, and blood albumin level of LN patients were recorded. Also, the correlation between TLR9 expression and these pathological indexes was measured by correlation analysis. RESULTS: Serum level of IL-23 in LN patients was significantly higher than that of healthy controls. Similarly, the mRNA and protein expressions of IL-23 in PBMCs of LN patients were markedly higher than those of healthy controls. IL-23 expression was positively correlated with renal tubular pathological activity index of LN patients. Meanwhile, TLR9 was highly expressed in renal tissues of LN patients. Furthermore, TLR9 expression was positively correlated with 24-h protein urine, renal tubular pathological activity index and ESR, whereas negatively correlated with serum complement C3 level and blood albumin level of LN patients. CONCLUSIONS: IL-23 is highly expressed in the serum of LN patients, and its expression is closely related to the occurrence of LN. Also, the expression of TLR9 is up-regulated in the tubulointerstitium of LN patients, which is correlated with relevant clinical indexes.