The Expression And Significance Of Toll-Like Receptor7 In Peripheral Plasmacytoid Dendritic Cells In Patients With Systemic Lupus Erythematosus

Objective:To investigate the expression of Toll like receptor 7(TLR7)in peripheral plasmacytoid dendritic cells(pDC)with systemic lupus erythematosus patients(SLE),and to explore the role and significance of TLR7 signal transduction pathway in the pathogenesis of SLE.Methods:Fifty-two inpatients diagnosed as SLE From March 2018 to August 2018 in the Department of Rheumatology and Immunology,First Affiliated Hospital of Bengbu Medical College were selected as SLE group.Tirty-two normal healthy persons from the First Affiliated Hospital of Bengbu Medical College were selected as the control group.Flow cytometry was used to detect the relative counts of pDC and mDC in peripheral blood and the expression level of TLR7 in pDC cells,and to correlate with the main clinical indicators and related laboratory parameters.Results:(1)The relative count of pDC in peripheral blood PBMC of SLE group was lower than that of the control group,the difference was statistically significant(uc=5.75,P=0.00).There was no significant difference in the relative count of mDC between SLE group and normal control group(t=0.84,P=0.40).(2)The relative count of peripheral blood pDC in infected patients with SLE was significantly lower than that in non-infected group(t=4.21,P=0.00).The relative count of mDC in peripheral blood of first-onset patients with SLE was lower than that of recurrent group,and the difference was statistically significant.(t=2.05,P=0.046).There was no significant difference of relative counts of pDC or mDC in activity group and stable group,proteinuria group and no proteinuria group,blood system affected group and non-involved group,anti-dsDNA antibody,anti-Sm antibody,in anti-SSA antibody,anti-SSB antibody positive group and negative group.The relative count of pDC showed a significant negative correlation with peripheral blood CRP(r=-0.33,P=0.02).(3)The proportion of TLR7~+pDC cells in peripheral blood of SLE group was higher as compared with healthy control group.the difference was statistically significant(uc=6.90,P=0.00).(4)The proportion of TLR7~+pDC cells in the affected group was significantly higher than that of the non-hematological group(uc=2.16,P=0.03).(5)There was no significant difference of the ratio of TLR7~+pDC cells between anti-dsDNA antibody,anti-Sm antibody,anti-SSA antibody,anti-SSB antibody positive group and negative group.TLR7~+pDC cell ratio and proteinuria grading showed a significant positive correlation(r=0.34,P=0.01).Conclusions:The relative counts of pDC and mDC in peripheral blood of patients with SLE were decreased,especially pDC,and there was a certain correlation with infection and recurrence and CRP production.The proportion of pDC expressing TLR7~+in peripheral blood of SLE patients was significantly increased,so TLR7 signal transduction pathways may play an important role in the pathogenesis of SLE.