OBJECTIVETo explore the expressions of B lymphocyte activating factor (BAFF) in the serum and peripheral blood B cells (PBBCs) of BXSB lupus nephritis mice, and to investigate the efficacy of Langchuangping Granule (LG).

METHODSEighteen 11-week-old male BXSB lupus mice were randomly divided into three groups, i.e., the lupus control group, the hormone treatment group, and the LG treatment group, 6 in each group. Besides, another 6 C57BL/6 male mice were recruited as the normal control group. The mice were given with normal sodium (10 mL/d), methylprednisolone (at the daily dose of 5 mg/kg), LG (at the daily dose of 4 g/kg), and the normal saline (10 mL/d) respectively by gastrogavage for 4 weeks. The urine protein, ds-DNA, and body weight were determined. The serum soluble BAFF (sBAFF), the expressions and changes of BAFF-mRNA in the PBBCs were detected using ELISA and RT-PCR respectively. The activity index (AI) and 24 h urine albumin excretion quantitation of renal pathological activities were observed. The correlation between ds-DNA and sBAFF were analyzed.

RESULTSThe level of sBAFF in serum, the BAFF mRNA level in PBBCs, 24 h urinary albumin excretion, and serum ds-DNA content increased more obviously in lupus mice than in the normal mice. After being treated by methylprednisolone or LG, the sBAFF and BAFF mRNA expressions decreased more obviously than before treatment, showing statistical difference (P<0.05). But there was no statistical difference in the sBAFF level or the BAFF mRNA expression (P>0.05). There was positive correlation between sBAFF and AI (r=0.8098, P<0.01), 24 h urinary albumin excretion (r=0.8220, P<0.01), and ds-DNA (r=0.8535, P<0.01).

CONCLUSIONSBAFF plays an important role in the occurrence and development of lupus nephritis. It can be used in monitoring the disease progress and predicting its recurrence. It is one of ideal targets for treating lupus nephritis. LG could attenuate the renal injury via suppressing BAFF level. It is worth further clinical application.