Objective To investigate the effects and mechanism of interleukin 33 (IL-33) on renal tubular injury in mice with lupus nephritis.Methods Twelve-week-old female MRL/lpr mice were randomly divided into model group,IL-33 group and solvent control group with 10 rats in each group.Ten female MRL/MP mice of the same age were used as normal control group.The mice in IL-33 group were intraperitoneally injected with 100 μL of phosphate buffer saline (PBS),containing 2 μg of recombinant mouse IL-33,once a day for 14 days.The mice in control group and the model group were intraperitoneally injected with the same dose of PBS.All the mice were sacrificed at 14 weeks of age.Serum creatinine (Cr) and urea nitrogen (BUN) concentrations were determined by serum separation.The urine in 24 hours was collected testing urinary protein creatinine ratio and urinary protein quantification.The contents of E-cadherin,α-SMA,and JAK/STAT pathway signaling proteins,including JAK2,p-JAK2,STAT1,and p-STAT1,were detected by Western blot.Results The BUN,urinary protein creatinine ratio and urine protein level of the IL-33 group were significantly higher than those of the model group (all P＜0.05).The expression of renal tubular epithelial cells o-SMA in the IL-33 group was higher than that in the model group,and the difference was statistically significant (P＜0.05).Compared with the model group,the expression of E-cadherin in the tubular epithelial cells of IL-33 group decreased and the expression of p-JAK2 and p-STAT1 protein increased,and the differences were all statistically significant (all P＜0.05).Compared with the model group,the levels of JAK2 and STAT1 in IL-33 group change little,and the differences were not statistically significant (all P＞0.05).Conclusions IL-33 can cause tubulointerstitial lesions in lupus mice,and its mechanism may be related to the activation of JAK/STAT pathway.

Objective:To analyze the correlation between T lymphocyte and transforming growth factor beta (TGF-β) levels and disease activity in patients with lupus nephritis (LN).Methods:A retrospective analysis was conducted on the clinical data of 160 patients with systemic lupus erythematosus (SLE) treated at the Xianyang Central Hospital from September 2018 to September 2023, including 100 LN patients and 60 non LN patients. Another 50 healthy volunteers who underwent physical examination at the Xianyang Central Hospital Physical Examination Center during the same period were selected as the control group. The levels of T lymphocytes [leukocyte differentiation antigen 3 (CD3 + ), leukocyte differentiation antigen 4 (CD4 + ), helper T cell 22 (Th22)] and TGF-β were compared among all subjects. The levels of T lymphocytes and TGF-β in LN patients with different disease activity and prognosis were compared. Spearman correlation coefficient was used to analyze the correlation between T lymphocytes, TGF-β levels and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score. Results:The serum levels of CD3 + and CD4 + in the LN group were lower than those in the non LN group, while the levels of Th22 and TGF-β were higher than those in the non LN group. The levels of CD3 + and CD4 + in the non LN group were lower than those in the control group, while the levels of Th22 and TGF-β were higher than those in the control group ( F=217.170, 311.154, 84.268, 56.952, all P<0.05); Comparison of serum CD3 + and CD4 + levels in LN patients with different disease activities: stable phase>mild activity>moderate activity>severe activity. Comparison of Th22 and TGF-β levels: stable phase