Study On The Clinical Significance Of Chemokine CXCL13 In Systemic Lupus Erythematosus

Objective: Systemic lupus erythematosus(SLE)is a chronic autoimmune disease with multiple systems and multiple organ involvement.Its pathogenesis is complex.It is generally believed that it is related to the abnormal immune response of T lymphocyte,B lymphocyte hight activation,immunoglobulin increase and so on.The proliferation and differentiation of B cells and abnormal function were the most prominent.CXC chemokine ligand 13(CXCL13)belongs to the CXC chemokine family,which is mainly produced by dendritic cells and macrophages in secondary lymphatic organs,and by binding with its receptor CXCR5,which Plays an important role in B lymphocyte migration,target finding and induction of the formation of germinal center(GC)in secondary lymphatic tissue.More and more studies have shown that it may plays an important role in the development of autoimmune diseases.This study is to detect the plasma level of chemokine CXCL13 in patients with SLE and to explore the expression and clinical significance of CXCL13 in SLE.Methods:sixty cases of SLE patients from the Rheumatology and Immunology,the first affiliated hospital of China Medical University,from January 2017 to December 2017,were recruited as the experimental group.According to whether the patient’s kidneys were affected,the SLE patients were divided into lupus nephritis(LN)group and non-LN group.At the same time,20 cases of health examination were selected as healthy control(HC)group.Plasma samples were obtained from all subjects and the plasma level of chemokine CXCL13 were detected by Enzyme-linked immunosorbent assay(ELISA).Collect the clinical data and laboratory indicators of SLE patients.The basic information including gender,age,course of disease.The clinical manifestations including fever,joint swelling,rash,oral ulcer,hair loss,serous inflammation.The laboratory indicators including white blood cell(WBC)counts,lymphocyte(LY)counts,hemoglobin(Hb)content,platelet(PLT)counts,immunoglobulin(Ig G,Ig A,Ig M),complement(C3,C4),anti-ds DNA antibody,anti-SM antibody,anti-histone antibody(AHA),serum creatinine(Scr),serum urea nitrogen(BUN),24 h urine protein quantification,urinary RBC/HPF,urinary WBC/HPF,tubular urine.The estimated glomerular filtration rate(e GFR)was estimated according to the Chronic Kidney Disease Epidemiology(CKD-EPI)equation.The disease activity of SLE patients was evaluated by systemic lupus erythematosus disease activity index(SLEDAI),SLEDAI >4 was defined as disease activity.The activity of lupus nephritis(r SLEDAI)was calculated according to the renal involvement score in SLEDAI,r SLEDAI≥4 was defined as lupus nephritis activity.Analyze the relationship between plasma CXCL13 levels and basic information,complement,immunoglobulin,autoantibodies,disease activity and the involvement of the blood system in SLE patients.Compare the differences of plasma CXCL13 levels between LN and non-LN patients,and to analyze the relationship between related indexes of renal injury in LN and disease activity index.The sensitivity and specificity of plasma CXCL13 in the diagnosis of LN were further analyzed by receiver-operating characteristic(ROC)curve.Analysis of variance,t-test and Pearson’s correlation test were used for statistical analysis.Result:The concentration of CXCL13 was elevated in plasma of SLE patients,which was significantly higher than healthy controls(P<0.01).The levels of plasma CXCL13 in SLE patients showed positive correlation with SLEDAI(r=0.267,P<0.05)and negative correlation with C3(r=-0.294,P<0.05),Hb(r=-0.299,P<0.05),PLT(r=-0.300,P<0.05),LY(r=-0.309,P<0.05),but not with C4,Ig G,Ig A or Ig M.Comparisons of CXCL13 levels between disease activity group and stabilization group demonstrated a higher level of CXCL13 in the former(P<0.01).The plasma CXCL13 levels were significantly higher in anti-ds DNA antibody positive group than in negative group(P<0.01).There was no significance difference in plasma CXCL13 levels between anti-Sm antibody positive group than in negative group(P>0.05).The plasma CXCL13 levels were significantly higher in AHA positive group than in negative group(P<0.05).The plasma CXCL13 levels were significantly higher in SLE patients with LN than those in patients without LN(P<0.01).The plasma CXCL13 levels were positively correlated with BUN(r=0.425,P<0.01)and negatively correlated with e GFR(r=-0.385,P<0.05)in LN patients,but not with 24 h urine protein quantification,Scr or r SLEDAI.positive group than in negative group(P<0.05).The sensitivity and specificity of plasma CXCL13 in diagnosing LN was 92.5% and 60.0% respectively at a cut-off value of 116.95pg/ml.Conclusion:The level of CXCL13 is elevated in the plasma of SLE patients.The levels of plasma CXCL13 were positively correlated with SLEDAI and negative correlation with C3,Hb,PLT and LY in SLE,and were were significantly higher in anti-ds DNA antibody or AHA positive group than in negative group.The plasma CXCL13 levels were significantly higher in SLE patients with LN than those in patients without LN.The plasma CXCL13 levels were positively correlated with BUN and negatively correlated with e GFR in LN patients,which has significant difference in the diagnosis of LN.Indicating it may play a role in the autoantibodies production,hematoloogical and renal involvement in SLE,which may be used as one of the serolgical markers to judge the activity of SLE.