Level And Clinical Significance Of Soluble ICOSL And VTCN1 In Patients With Systemic Lupus Erythematosus

Background: Systemic lupus erythematosus(SLE)is a kind of immune-mediated destruction and are characterized by the breakdown of self-tolerance as well as the deposition of circulating immune complexes in blood vessels throughout the body.Lupus nephritis(LN)is one of the most common complications of SLE.ICOSL(Inducible costimulatory molecule)VTCN1(V-set domain containing T cell activation inhibitor 1,VTCN1)are members of B7/CD28 family,which control the activation,proliferation and apoptosis of lymphocytes.Objective: To investigate the level of costimulating molecules in SLE,we assessed the plasma concentration of soluble form of ICOSL and VTCN1.MethodsTo well understand the role of members of B7 family in diseases,plasma concentration of soluble ICOSL and VTCN1 were measured by ELISA(Enzyme-Linked Immunosorbnent Assay,ELISA)using plasma samples from 49 SLE patients and 33 Age-and gender-matched healthy volunteers.All patients were obtained from the Departments of Rheumatology and Nephrology of the First and Second Affiliated Hospital of Anhui Medical University from March 2015 to August2015.All clinical laboratory characteristics were collected from hospital system.Results(1)Compared with healthy controls,the levels of serum ICOSL in SLE patients or LN patients were significantly lower(SLE: 1.63±0.67ng/ml,P=0.004;LN:1.66±0.67ng/ml,P=0.008).The concentration of plasma VTCN1 in SLE or LN patients were significantly higher compared with healthy subjects(0.63±0.26 VS0.52±0.11ng/ml,P = 0.006;0.66±0.27 VS 0.52±0.11ng/ml,P = 0.008).(2)On the other hand,we discovered that concentration of VTCN1 in patients with active disease was decreased compared with inactive disease(0.54±0.19 VS 0.74±0.29 ng/ml,P=0.002).No significant difference between LN and non-LN was discovered.(3)No correlations between the concentration of serum ICOSL and disease activity or clinical indicators were discovered,and laboratory indexes in negative groups and positive groups did not show significant difference.Additionally,plasma VTCN1 concentration in patients with SLE correlated modestly negative with the SLE disease activity index score(SLEDAI)(r =-0.3055,P = 0.022).(4)Moreover,the application of corticosteroids or immune-suppressants did not affect the concentration of the serum ICOSL or VTCN1 in SLE patients(P=0.495,P=0.371).Conclusions ICOSL and VTCN1 may be involved in the development of SLE or LN.But the exact physiological role of soluble ICOSL and VTCN1 involved in the pathogenesis of SLE remains controversial and to be investigated.