Study On The Role Of Inflammatory Immune Molecules And Vascular Inflammatory Response In The Pathogenesis Of Vogt-Koyanagi-Harada Diseas

Part One Investigation of the serum interleukin-33 level and its associated factors in patients with Vogt-Koyanagi-Harada diseaseObjectives:To measure the serum level of IL-33 in patients with Vogt-Koyanagi-Harada disease(VKH)in the Chinese Han population,and investigate its associations with disease activity and clinical parameters.Methods:Serum was collected from 41 VKH patients(16 active and 25 inactive patients)and 36 healthy controls.The serum level of IL-33 was measured using the enzyme-linked immunosorbent assay(ELISA)method.Correlations were analyzed between IL-33 level and demographic features,clinical manifestations,and intraocular inflammation activity scores(anterior chamber cells score,anterior chamber flare score,and vitreal haze score).Results:The serum level of IL-33 significantly increased in all VKH patients,active VKH patients,and inactive VKH patients,as compared to healthy controls(p<0.001,p<0.001,and p=0.002,respectively),and was higher in the active VKH than in the inactive VKH patients(p=0.049).The serum level of IL-33 positively correlated with the anterior chamber cells score,vitreal haze score,and the annualized number of relapses in VKH patients(Rho=0.359,p=0.021;Rho=0.344,p=0.028;Rho=0.537,p<0.001,respectively).Conclusion:Serum IL-33 level is significantly increased in VKH patients in the Chinese Han population.IL-33 level is in positive correlation with the disease activity and relapses of VKH.Increased IL-33 might contribute to the pathogenesis of VKH and serve as a potential biomarker for VKH disease.Part Two The expression pattern and clinical significance of the immune checkpoint molecule VISTA in patients with Vogt-Koyanagi-Harada diseaseObjectives:To detect the expression profile of immune checkpoint molecule V-domain Ig suppressor of T cell activation(VISTA)in peripheral blood immune cells of healthy Chinese Han volunteers and patients with Vogt Koyanagi Harada disease(VKH),and investigate the potential relationships between VISTA expression pattern and VKH disease.Methods:In the first stage study,9 healthy volunteers and 16 VKH patients(8 active and 8 inactive patients)were included.Demographic features and clinical manifestations of the participants were recorded.The expression levels of VISTA on the surface of peripheral blood monocytes,neutrophils,myeloid dendritic cells(mDC),plasmacytoid DC cells(pDC),B lymphocytes,natural killer cells(NK),NKT cells,CD8+T lymphocytes,CD4+T lymphocytes,regulatory T cells,T helper cells 1(Th1),Th2 cells,and Th17 cells were measured by using multi-color flow cytometry,and differentially expressed cell types were screened.In the second stage study,four patients with active VKH were included.Flow cytometry was respectively performed at the active phase and inactive phase(3 months after the inflammation remission)to verify the change patterns of VISTA expression.Results:VISTA was constitutively highly expressed on the surface of peripheral blood myeloid cells,especially on monocytes,neutrophils,and DCs,while all subsets of T lymphocytes,B lymphocytes,NK cells and NKT cells expressed quite low levels of VISTA.The mean fluorescence intensity(MFI)of VISTA in all subsets of peripheral blood cells was lower in VKH patients than that in healthy volunteers.Amongst,the MFI of VISTA in monocytes was significantly lower in VKH patients(p=0.024).Furthermore,MFI of VISTA in monocytes was lower in active VKH patients than that in healthy controls(p=0.043).Comparisons between active VKH patients and inactive VKH patients showed alterations in VISTA expression among different cell subsets.In the selfcontrolled study,VISTA MFI in monocytes,neutrophils,and DCs of active VKH was greatly increased in the inactive stage,but with no statistical significance(p>0.05).There was no significant correlation between VISTA expression and clinical parameters in VKH disease.Conclusion:VISTA is mainly expressed on the surface of human peripheral blood myeloid cells.The expression of VISTA decreases in various cell subsets in VKH patients,especially in monocytes.VISTA expression in myeloid cells was lower in active VKH patients than in the inactive patients.Part Three Assessment of choroidal vascular inflammatory changes in VogtKoyanagi-Harada DiseaseObjectives:To investigate choroidal vascular inflammatory changes in patients with Vogt-Koyanagi-Harada disease(VKH)using widefield swept-source optical coherence tomography angiography(SS-OCTA).Methods:133 eyes of 69 patients with VKH(52 eyes of 28 active VKH patients and 81 eyes of 41 inactive VKH patients)and 104 eyes of 52 healthy volunteers were imaged using a widefield SS-OCTA instrument.On 12 mm × 12 mm OCTA scans,mean choroidal thickness(MCT),choroidal vascularity index(CVI),and choriocapillaris(CC)flow area were separately calculated in the fovea(diameter of 1 mm)and in concentric rings of different diameters(1-3,3-6,6-9,and 9-12 mm),and the presence of flow voids was documented.Results:Eyes with active VKH showed significant increases in MCT and CVI,and decreased CC flow area in all central and peripheral regions(0-1,1-3,3-6,6-9,and 9-12 mm)than in the healthy eyes and inactive VKH eyes(p<0.05 for all).Inactive VKH eyes only showed marked decrease in CC flow area in all regions compared with controls(p<0.05 for all).Flow voids were observed in 48 of 52(92.3%)active VKH eyes and 50 of 81(61.7%)inactive VKH eyes on 12 mm × 12 mm OCTA(p<0.001).The MCT of all regions was significantly correlated with age,disease duration,and disease activity,whereas CVI was associated with age and disease activity.The CC flow void was related to visual acuity in all regions(p<0.05 for all).Conclusion:In active VKH patients,choroidal thickening,luminal enlargement,and decreases in choroidal capillary flow are observed both in the central and peripheral choroid,and are especially significant in the posterior pole;However,in inactive VKH patients,choroidal thinning and vessel shrinkage may occur from the peripheral region.