Chunjiang Zhou

Vogt-Koyanagi-Harada disease presenting as acute angle closure glaucoma at onset

Background:  To investigate the clinical features of Vogt‐Koyanagi‐Harada (VKH) disease presenting as acute angle closure glaucoma at onset.

Gut Microbiota Composition and Fecal Metabolic Phenotype in Patients With Acute Anterior Uveitis

Purpose To investigate gut microbiota composition and fecal metabolic phenotype in patients with acute anterior uveitis. Methods Fecal DNA was extracted from 78 fecal samples (38 acute anterior uveitis (AAU) patients and 40 family members of patients or sex- and age-matched healthy controls) and then sequenced by high-throughput 16S rDNA analysis. Gas chromatographic mass spectrometry (GC-MS) based metabolomics was performed on 60 fecal samples (30 AAU patients and 30 healthy controls). Results A significant difference was observed in beta diversity between AAU patients and healthy controls. Eight genera including Roseburia were reduced in AAU patients, and Veillonella was increased in AAU patients as compared with healthy controls. Significance was however lost after false discovery rate (FDR) correction. The expression of seven fecal metabolites including 6-deoxy-D-glucose 1, linoleic acid, N-Acetyl-beta-D-mannosamine 3, shikimic acid, azelaic acid, isomaltose 1 and palmitoleic acid was increased in AAU patients. Linoleic acid showed a significant correlation with Roseburia and Veillonella according to Spearman correlation analysis. Conclusions Our results did not reveal a difference in gut microbiota composition, but did show that the fecal metabolic phenotype in AAU patients was significantly different from healthy controls.

MicroRNA-20a-5p suppresses IL-17 production by targeting OSM and CCL1 in patients with Vogt-Koyanagi-Harada disease

Aim To elucidate the role of microRNA-20a-5p (miR-20a-5p) in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease. Methods Quantitative real-time PCR was used to quantify miR-20a-5p expression in CD4+ T cells from patients with active VKH and normal controls. The promoter methylation status of miR-20a-5p was detected by bisulfite sequencing PCR. Targets were evaluated by a luciferase reporter assay. The functional effects of miR-20a-5p on CD4+ T cells from patients with active VKH were assessed by upregulation or downregulation of its expression using liposomes. Results The miR-20a-5p level was significantly decreased in CD4+ T cells from patients with active VKH as compared with normal controls. The two genes, oncostatin M (OSM) and C-C motif chemokine ligand 1 (CCL1), were identified as targets of miR-20a-5p. The upregulation of miR-20a-5p significantly suppressed interleukin 17 (IL-17) production in CD4+ T cells from patients with active VKH, whereas downregulation of miR-20a-5p exhibited an inverse effect. In addition, overexpression of OSM and CCL1 could rescue the effect of the upregulation of miR-20a-5p. Moreover, the level of miR-20a-5p was reduced in response to hypermethylation of the promoter. Further study showed that miR-20a-5p suppressed the activity of the phosphoinositide 3-kinase-AKT pathway. Conclusions Our findings indicate that downregulation of miR-20a-5p is caused by promoter hypermethylation. MiR-20a-5p could also suppress the production of IL-17 by targeting OSM and CCL1 production in CD4+ T cells in patients with active VKH.

Association of genetic variations in PTPN2 and CD122 with ocular Behcet’s disease

Background Protein tyrosine phosphatases (PTPs) play critical roles in human autoimmunity. Previous studies found that PTPN2 may be the key regulatory factor in the T-cell-mediated immune response. PTPN2 regulates the Janus kinase/signal transducers and activators of transcription pathway by inhibiting signalling via the interleukin (IL)-2 receptor (CD122). An association between genetic variations in PTPN2 and CD122 with ocular Behcet’s disease (BD) has not yet been addressed and was therefore the purpose of this study. Methods A two-stage case–control study was performed in 906 patients with ocular BD and 2178 healthy controls. Genotyping analysis of 11 single nucleotide polymorphisms was carried out. The expression of PTPN2 in peripheral blood mononuclear cells (PBMCs) was quantified by real-time PCR and cytokine production was measured by ELISA. Results The frequency of the GG genotype of PTPN2-rs7234029 was significantly lower in patients with ocular BD (p=1.94×10−5, pc=8.34×10−4, OR=0.466). Stratification according to gender showed that rs7234029 was significantly associated with BD in men. A stratified analysis according to the main clinical features showed that rs7234029 was significantly associated with genital ulcers, skin lesions and a positive pathergy test. No association could be detected between BD and CD122 gene polymorphisms. Functional studies showed that rs7234029 GG genotype carriers had a higher PNPT2 mRNA expression level than those which carrying the AA or AG genotype, and a decreased secretion of IL-17 and tumour necrosis factor-alpha was seen by PBMCs from GG carriers. No significant difference could be detected concerning IL-1β or IL-6 production by stimulated PBMCs between the different genotype groups. Conclusions This study shows that a PTPN2-rs7234029 polymorphism is associated with ocular BD and is strongly influenced by gender. In addition, our results suggest that the genetic association with PTPN2 may involve the regulation of PTPN2 mRNA expression and cytokine secretion.

A metagenomic study of the gut microbiome in Behcet’s disease

BackgroundBehcet’s disease (BD) is a recalcitrant, multisystemic inflammatory disease that can lead to irreversible blindness. Microbial agents have been considered to contribute to the pathogenesis of this disease, but the underlying mechanisms remain unclear. In this study, we investigated the association of gut microbiome composition with BD as well as its possible roles in the development of this disease.MethodsFecal and saliva samples were collected from 32 active BD patients and 74 healthy controls. DNA extracted from fecal samples was subjected to metagenomic analysis, whereas DNA extracted from saliva samples was subjected to 16S rRNA gene sequencing analysis. The results were used to compare the composition and biological function of the microbiome between patients and healthy controls. Lastly, transplantation of pooled fecal samples from active BD patients into B10RIII mice undergoing experimental autoimmune uveitis (EAU) was performed to determine the causal relationship between the gut microbiome and BD.ResultsFecal samples from active BD patients were shown to be enriched in Bilophila spp., a sulfate-reducing bacteria (SRB) and several opportunistic pathogens (e.g., Parabacteroides spp. and Paraprevotella spp.) along with a lower level of butyrate-producing bacteria (BPB) Clostridium spp. and methanogens (Methanoculleus spp. Methanomethylophilus spp.). Analysis of microbial functions revealed that capsular polysaccharide transport system, oxidation-reduction process, type III, and type IV secretion systems were also increased in active BD patients. Network analysis showed that the BD-enriched SRB and opportunistic pathogens were positively correlated with each other, but they were negatively associated with the BPB and methanogens. Animal experiments revealed that fecal microbiota transplantation with feces from BD patients significantly exacerbated EAU activity and increased the production of inflammatory cytokines including IL-17 and IFN-γ.ConclusionsOur findings revealed that BD is associated with considerable gut microbiome changes, which is corroborated by a mouse study of fecal microbiota transplants. A model explaining the association of the gut microbiome composition with BD pathogenesis is proposed.

Disabled-2 (DAB2) Overexpression Inhibits Monocyte-Derived Dendritic Cells' Function in Vogt-Koyanagi-Harada Disease

Purpose Recent studies reported that the tumor suppressor disabled-2 (DAB2) is a negative regulator of immune function. In this study, we investigated the role of DAB2 in monocyte-derived dendritic cells (DCs) from Vogt-Koyanagi-Harada disease (VKH) patients. Methods The mRNA and protein levels of DAB2 were quantified by quantitative real-time PCR and Western blot. The Sequenom MassARRAY system was used to detect the promoter methylation level. An adenovirus carrying the DAB2 gene was transduced into immature DCs, isolated, and induced from active VKH patients. The surface markers of DCs, the frequency of T helper (Th) type 1 (Th1) and Th17 cells in CD4+T cells, which were cocultured with DCs, were tested by flow cytometry. ELISA was used to analyze the inflammatory cytokines produced by DC and CD4+T cell cocultures. Results The mRNA and protein expression levels of DAB2 in DCs obtained from active VKH patients were decreased, while the DAB2 promoter methylation level was marginally increased when compared with inactive VKH patients and normal controls. The expression of CD86 on DCs was significantly downregulated by DAB2 overexpression. The DC-related inflammatory factors IL-6 and TNF-α were also decreased. The frequency of Th1 and Th17 cells and their related cytokines were reduced significantly after coculture with DAB2 overexpressing DCs. DAB2 overexpression did not affect autophagy in DCs from VKH patients. Conclusions These results suggest that the decreased expression of DAB2 in DCs plays a role in the pathogenesis of VKH disease. DAB2 overexpression inhibits DC function, but this is not mediated via autophagy.

Association of Long Noncoding RNAs Polymorphisms With Ankylosing Spondylitis, Vogt-Koyanagi-Harada Disease, and Behcet's Disease

Purpose Long noncoding RNAs (lncRNAs) are emerging as important regulators of inflammatory immune responses, whereby genetic variants may affect this biologic function. This study aimed to investigate the association of 110 single nucleotide polymorphisms (SNPs) of lncRNAs, known to be associated with autoimmune disease, in patients with ocular Vogt-Koyanagi-Harada (VKH) disease, Behcets disease (BD), and acute anterior uveitis (AAU) with or without ankylosing spondylitis (AS). Methods A two-stage case-control study was performed on 1626 VKH patients, 384 BD patients, 624 AAU with AS, 751 AAU without AS, 720 AS without AAU, and 3305 healthy subjects. lncRNAs 110 SNPs were genotyped using MassARRAY System or TaqMan SNP assays. The gene expression and cytokine production were measured using real-time PCR or ELISA. Results The frequency of the C allele of rs4937362 in RP11-264E20.1 was markedly decreased in the AS without AAU group compared with controls (Combined P = 9.37 × 10-7, odds ratio [OR] = 0.73). An increased frequency of the A allele of rs6871626 between UBLCP1, IL12B, and LOC285627 was found in VKH patients compared with controls (Combined P = 1.88 × 10-4, OR = 1.19). UBLCP1, IL12B, and LOC285627 were expressed in human uveal tissues. Functional studies showed a decreased LOC285627 mRNA expression in peripheral blood mononuclear cells (PBMCs) and an increased IL-10 production in PBMCs following LPS stimulation in rs6871626 CC genotype carriers. Conclusions Our study is the first to show that rs4937362/RP11-264E20.1 is associated with AS and that rs6871626 is associated with VKH disease in Chinese Han. The protective rs6871626 genotype was shown to regulate the expression of LOC285627 and to increase the production of the anti-inflammatory cytokine IL-10.

Association of LACC1, CEBPB-PTPN1, RIPK2 and ADO-EGR2 with ocular Behcet’s disease in a Chinese Han population

Background An Immunochip study recently identified the association of a number of new genetic loci with Behcet’s disease (BD). Objective To confirm the association between new genetic loci reported in an Immunochip study and BD in a Han Chinese population. Methods A two-stage association study was carried out in 1238 patients with BD and 1458 healthy controls. Twenty-two candidate single nucleotide polymorphisms (SNPs) were selected for genotyping by iPLEXGold genotyping or TaqMan SNP assays and a meta-analysis was performed for significantly associated markers. Results The results showed that four SNPs (LACC1/rs9316059, CEBPB-PTPN1/rs913678, ADO-EGR2/rs224127 and RIPK2/rs10094579) were associated with BD in an allelic association test (rs9316059 T allele: pc=4.95×10−8, OR=0.687; rs913678 C allele: pc=3.01×10−4, OR=1.297; rs224127 A allele: pc=3.77×10−4, OR=1.274; rs10094579 A allele: pc=6.93×10−4, OR=1.302). For four SNPs tested by meta-analysis, the association with BD was strengthened and all exceeded genome-wide significance (rs9316059: p=2.96×10−16; rs913678: p=2.09×10−16; rs224127: p=5.28×10−13; rs10094579: p=9.21×10−11). Conclusions Our findings confirmed the association of four loci (LACC1, CEBPB-PTPN1, ADO-EGR2 and RIPK2) in Chinese Han patients with BD.

The Choroidal Vascularity Index Decreases and Choroidal Thickness Increases in Vogt–Koyanagi–Harada Disease Patients During a Recurrent Anterior Uveitis Attack

ABSTRACT Purpose: To measure changes in the choroidal vascularity index (CVI) in chronic Vogt–Koyanagi–Harada (VKH) disease during a recurrent anterior uveitis attack. Methods: Forty VKH patients and 40 normal controls were included in this study. Choroidal images were recorded before and during a recurrent anterior uveitis attack, as well as after appropriate treatment. CVI was measured by the binarization technique using ImageJ software (Bethesda, MD). Results: The CVI was 0.75 ± 0.09 in quiescent VKH patients, which was significantly higher compared to healthy controls (0.70 ± 0.05, p ＜ 0.0001). The CVI significantly decreased to 0.72 ± 0.09 when granulomatous anterior uveitis appeared in these patients. However, it returned to 0.75 ± 0.08 after uveitis resolved. Conclusions: A significant decrease of the CVI occurred during recurrent anterior uveitis in chronic VKH. CVI may provide a novel parameter to guide the treatment of VKH disease.