E. coli and the etiology of human PBC: Antimitochondrial antibodies and spreading determinants.

BACKGROUND AND AIMS: The increased frequency of urinary tract infections in patients with primary biliary cholangitis (PBC) and the cross-reactivity between the lipoyl domains (LD) of human pyruvate dehydrogenase complex (hPDC-E2) and Escherichia coli PDC-E2 (ePDC-E2) have long suggested a role of E. coli in causality of PBC. This issue, however, has remained speculative. We hypothesized that by generating specific constructs of human and E. coli PDC-E2, we would be able to assess the specificity of autoantibody responses and define whether exposure to E. coli in susceptible hosts is the basis for the antimitochondrial antibody (AMA) response. APPROACH AND RESULTS: Importantly, the reactivity of hPDC-E2 LD (hPDC-E2LD) affinity-purified antibodies against hPDC-E2LD could only be removed by prior absorption with hPDC-E2LD and not ePDC-E2, suggesting the presence of unique human PDC-E2 epitopes distinct from E. coli PDC-E2. To identify the autoepitope(s) present in hPDC-E2LD, a more detailed study using a variety of PDC-E2 constructs was tested, including the effect of lipoic acid (LA) on ePDC-E2 conformation and AMA recognition. Individual recombinant ePDCE2 LD domains LD1, LD2 and LD3 did not react with either AMA or antibodies to LA (anti-LA), but in contrast, anti-LA was readily reactive against purified recombinant LD1, LD2, and LD3 expressed in tandem (LP); such reactivity increased when LP was precultured with LA. Moreover, when the three LD (LD1, LD2, LD3) domains were expressed in tandem in pET28a or when LD1 was expressed in another plasmid pGEX, they were lipoylated and reactive to PBC sera. CONCLUSIONS: In conclusion, our data are consistent with an exposure to E. coli that elicits specific antibody to ePDC-E2 resulting in determinant spreading and the classic autoantibody to hPDC-E2LD. We argue this is the first step to development of human PBC.

TNF-α Induces Mitophagy in Rheumatoid Arthritis Synovial Fibroblasts, and Mitophagy Inhibition Alleviates Synovitis in Collagen Antibody-Induced Arthritis.

Mitophagy is a selective form of autophagy that removes damaged mitochondria. Increasing evidence indicates that dysregulated mitophagy is implicated in numerous autoimmune diseases, but the role of mitophagy in rheumatoid arthritis (RA) has not yet been reported. The aim of the present study was to determine the roles of mitophagy in patient-derived RA synovial fibroblasts (RASFs) and in the collagen antibody-induced arthritis mouse model. We measured the mitophagy marker PTEN-induced putative kinase 1 (PINK1) in RASFs treated with tumor necrosis factor-α (TNF-α) using Western blotting and immunofluorescence. Arthritis was induced in PINK1-/- mice by intraperitoneal injection of an anti-type II collagen antibody cocktail and lipopolysaccharide. RA severity was assessed by histopathology. PINK1 expression and damaged mitochondria increased in TNF-α treated RASFs via increased intracellular levels of reactive oxygen species. PINK1 knockdown RASFs decreased cellular migration and invasion functions. In addition, PINK1-/- mice with arthritis exhibited markedly reduced swelling and inflammation relative to wild-type mice with arthritis. Taken together, these findings suggest that regulation of PINK1 expression in RA could represent a potential therapeutic and diagnostic target for RA.

The fingerprint of antimitochondrial antibodies and the etiology of primary biliary cholangitis.

The identification of environmental factors that lead to loss of tolerance has been coined the holy grail of autoimmunity. Our work has focused on the reactivity of antimitochondrial autoantibodies (AMA) to chemical xenobiotics and has hypothesized that a modified peptide within PDC-E2, the major mitochondrial autoantigen, will have been immunologically recognized at the time of loss of tolerance. Herein, we successfully applied intein technology to construct a PDC-E2 protein fragment containing amino acid residues 177-314 of PDC-E2 by joining a recombinant peptide spanning residues 177-252 (PDC-228) with a 62-residue synthetic peptide from 253 to 314 (PP), which encompasses PDC-E2 inner lipoyl domain (ILD). We named this intein-constructed fragment PPL. Importantly, PPL, as well as lipoic acid conjugated PPL (LA-PPL) and xenobiotic 2-octynoic acid conjugated PPL (2OA-PPL), are recognized by AMA. Of great importance, AMA has specificity for the 2OA-modified PDC-E2 ILD peptide backbone distinct from antibodies that react with native lipoylated PDC-E2 peptide. Interestingly, this unique AMA subfraction is of the immunoglobulin M isotype and more dominant in early-stage primary biliary cholangitis (PBC), suggesting that exposure to 2OA-PPL-like compounds occurs early in the generation of AMA. To understand the structural basis of this differential recognition, we analyzed PPL, LA-PPL, and 2OA-PPL using electron paramagnetic resonance spectroscopy, with confirmations by enzyme-linked immunosorbent assay, immunoblotting, and affinity antibody analysis. We demonstrate that the conformation of PDC-E2 ILD is altered when conjugated with 2OA, compared to conjugation with lipoic acid. CONCLUSION: A molecular understanding of the conformation of xenobiotic-modified PDC-E2 is critical for understanding xenobiotic modification and loss of tolerance in PBC with widespread implications for a role of environmental chemicals in the induction of autoimmunity. (Hepatology 2017;65:1670-1682).

Dendritic Cell Immunotherapy Combined with Cytokine-Induced Killer Cells Effectively Suppresses Established Hepatocellular Carcinomas in Mice.

BACKGROUND: The response of hepatocellular carcinoma (HCC) to immunotherapy is often disappointing and new strategies are clearly needed. The aim of the present study was to investigate whether cytokine-induced killer (CIK) cells combined with a dendritic cell vaccination enhanced cytotoxicity against hepatocarcinoma tumor cells in an in vivo animal model. METHODS: CIKs and DCs were prepared from C3H/HeJ mice by conventional methods, the dendritic cell (DC) pulsed with a MH134 cell lysate, DC or CIK alone were used as controls. Cell phenotypes were analyzed by flow cytometry, cytokine secretion levels were determined by enzyme-linked immunosorbent assay (ELISA), and cytotoxicity was assessed by means of an in vitro lactate dehydrogenase (LDH) release assay. A mouse hepatocarcinoma cell MH134-bearing mice model was established to test the in vivo anti-tumor efficacy of the system. RESULTS: CIK cells combined with DC therapy resulted in significant inhibition of tumor growth compared with the control group, whereas the decrease in tumor growth in mice that had been treated with CIK or DC alone did not reach the level of statistical significance. The combination therapy led to a further increase in the population of cytotoxic T cells (CTLs) in vivo, compared to the CIK or DC alone therapy. In addition, the combination therapy significantly enhanced cytotoxic activity against MH134 cells. CONCLUSION: Taken together, these results show that a DC + CIK vaccination is more effective than DC or CIK alone therapy for the treatment of hepatocarcinoma cancer.

Osteoprotegerin causes apoptosis of endothelial progenitor cells by induction of oxidative stress.

OBJECTIVE: Elevated serum osteoprotegerin (OPG) levels represent an independent risk factor for atherosclerotic disease, although the underlying mechanism is not clear. The aim of this study was to investigate the association of serum OPG levels and circulating endothelial progenitor cell (EPC) numbers, and to explore the effect of OPG on EPC apoptosis and its underlying mechanisms. METHODS: Flow cytometry was used to enumerate EPCs in the peripheral blood of 91 patients with systemic lupus erythematosus (SLE). Cultured EPCs, isolated from peripheral blood, were challenged with OPG, and apoptosis was evaluated by TUNEL staining. Expression of apoptosis-related proteins was measured by real-time quantitative polymerase chain reaction (qPCR) and Western blotting. Reactive oxygen species (ROS) were detected by flow cytometry, and the expression of NADPH oxidase (NOX) and MAP kinases (MAPK) was measured by qPCR and Western blotting. RESULTS: The serum OPG level was independently associated with reduced numbers of EPCs in patients with SLE. In vitro treatment with OPG significantly induced apoptosis of EPCs; this effect was mediated by syndecan 4. OPG-induced apoptosis was abolished by the ROS scavenger N-acetylcysteine and the NOX inhibitor diphenyleniodonium. OPG increased ROS production through activation of NOX-2 and NOX-4 and triggered phosphorylation of ERK-1/2 and p38 MAPK. Quenching of ROS by knockdown of NOX-2 or NOX-4 transcripts inhibited phosphorylation of ERK-1/2 and p38 MAPK. Moreover, inhibitors of ERK-1/2 and p38 MAPK decreased ROS production and subsequent EPC apoptosis, indicating a feed-forward loop between NOX and MAPK to amplify ROS production related to apoptosis. CONCLUSION: Elevated OPG levels increase apoptosis of EPCs by induction of oxidative stress.

Long-term safety and tolerability of subretinal transplantation of embryonic stem cell-derived retinal pigment epithelium in Asian Stargardt disease patients.

BACKGROUND: Although human embryonic stem cells (hESCs) have been considered a potential therapeutic option for regenerative medicine, there are some concerns regarding tumorigenicity, immunogenicity and ethical considerations. Stargardt macular dystrophy (SMD) is the most common form of juvenile macular degeneration that causes early onset blindness. Therapeutic options for SMD remain limited, although several treatment strategies are currently under investigation. Here, we report a 3-year assessment of a phase I clinical trial involving subretinal transplantation of hESC-retinal pigment epithelium (RPE) cells in patients with SMD. METHODS: This prospective, non-randomised clinical trial included three patients with SMD. All transplant recipients had central visual acuity no better than 20/400. Trans-pars plana vitrectomy was performed in the eye with poorer vision. RPE cells were reconstituted in balanced salt solution plus, then injected into the subretinal space using a semi-automated subretinal injection method. RESULTS: No serious adverse events occurred throughout the 3-year period following the injection of hESC-RPE cells. The functional and anatomical results were favourable, compared with the natural course of SMD reported in the ProgStar study. One patient showed best-corrected visual acuity improvement, while the other patients had stable best-corrected visual acuity during the 3-year follow-up period. CONCLUSION: These results suggest the long-term safety, tolerability, and feasibility of subretinal hESC-derived RPE cell transplantation in regenerative medicine. TRIAL REGISTRATION NUMBER: NCT01625559.

A contemporary perspective on the molecular characteristics of mitochondrial autoantigens and diagnosis in primary biliary cholangitis.

Primary biliary cholangitis (PBC) is an autoimmune hepatobiliary disease characterized by immune mediated destruction of the intrahepatic small bile ducts and the presence of antimitochondrial antibodies (AMAs). The mitochondrial autoantigens have been identified as the E2 subunits of the 2-oxo-acid dehydrogenase complex, including the E2 subunits of pyruvate dehydrogenase, branched-chain 2-oxo acid dehydrogenase complex, oxoglutarate dehydrogenase complex, E3 binding protein and PDC E1 alpha subunit. The AMA epitope is mapped within the E2 lipoic acid binding domain, which is particularly important for oxidative phosphorylation. In addition, lipoic acid, which serves as a swinging arm to capture electrons, is particularly susceptible to an electrophilic attack and may provide clues to the etiology of PBC. This review emphasizes the molecular characteristics of AMAs, including detection, immunochemistry and the putative role in disease. These data have significance not only specifically for PBC, but generically for autoimmunity.

Chemokine and chemokine receptors in autoimmunity: the case of primary biliary cholangitis.

Chemokines represent a major mediator of innate immunity and play a key role in the selective recruitment of cells during localized inflammatory responses. Beyond critical extracellular mediators of leukocyte trafficking, chemokines and their cognate receptors are expressed by a variety of resident and infiltrating cells (monocytes, lymphocytes, NK cells, mast cells, and NKT cells). Chemokines represent ideal candidates for mechanistic studies (particularly in murine models) to better understand the pathogenesis of chronic inflammation and possibly become biomarkers of disease. Nonetheless, therapeutic approaches targeting chemokines have led to unsatisfactory results in rheumatoid arthritis, while biologics against pro-inflammatory cytokines are being used worldwide with success. In this comprehensive review we will discuss the evidence supporting the involvement of chemokines and their specific receptors in mediating the effector cell response, utilizing the autoimmune/primary biliary cholangitis setting as a paradigm.

Xenobiotics and loss of tolerance in primary biliary cholangitis.

Data from genome wide association studies and geoepidemiological studies established that a combination of genetic predisposition and environmental stimulation is required for the loss of tolerance in primary biliary cholangitis (PBC). The serologic hallmark of PBC are the presence of high titer anti-mitochondrial autoantibodies (AMA) that recognize the lipoyl domain of the mitochondrial pyruvate dehydrogenase E2 (PDC-E2) subunit. Extensive efforts have been directed to investigate the molecular basis of AMA. Recently, experimental data has pointed to the thesis that the breaking of tolerance to PDC-E2 is a pivotal event in the initial etiology of PBC, including environmental xenobiotics including those commonly found in cosmetics and food additives, suggesting that chemical modification of the PDC-E2 epitope may render its vulnerable to become a neo-antigen and trigger an immune response in genetically susceptible hosts. Here, we will discuss the natural history, genetics and immunobiology of PBC and structural constraints of PDC-E2 in AMA recognition which makes it vulnerable to chemical modification.

Rosiglitazone-mediated dendritic cells ameliorate collagen-induced arthritis in mice.

Rosiglitazone is a selective ligand for peroxisome proliferator-activated receptor-gamma (PPAR-γ), which serves diverse biological functions. A number of autoimmune disease models have been used to examine the anti-inflammatory and immunosuppressive effects of tolerogenic dendritic cells (tDCs). The aim of the present study was to investigate whether rosiglitazone-mediated DC (Rosi-DC) therapy suppressed arthritis in a collagen-induced arthritis (CIA) mouse model. Rosi-DCs were generated by treating immature DCs with TNF-α, type II collagen, and rosiglitazone. CIA mice then received subcutaneously (s.c.) two injections of Rosi-DCs. The severity of arthritis was then assessed histopathologically. The phenotypes of the DC and regulatory T (Treg) cell populations in CIA mice were determined by flow cytometry and the effect of Rosi-DCs on the secretion of autoimmunity-inducing cytokines was examined by ELISA. Rosi-DCs expressed lower levels of DC-related surface markers than mature DCs. Histopathological examination revealed that the degree of inflammation in the paws of Rosi-DC-treated mice was much lower than that in the paws of PBS-treated CIA mice. Taken together, these results clearly show that rosiglitazone-mediated DCs ameliorate CIA, most likely via the induction of antigen-specific Treg cells.

Tolerogenic dendritic cells show gene expression profiles that are different from those of immunogenic dendritic cells in DBA/1 mice.

Tolerogenic dendritic cells (tDCs) play an important role in inducing peripheral tolerance; however, few tDC-specific markers have been identified. The aims of this study were to examine whether tDCs show a different gene expression profile from that of immunogenic DCs and identify specific gene markers of each cell type, in DBA/1 mice. tDCs were generated by treating immature DCs (imDCs) with TNF-α and type II collagen. The gene expression profiles of mature (m)DCs and tDCs were then investigated by microarray analysis and candidate markers were validated by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Supervised selection identified 75 gene signatures, 63 of which were consistently upregulated in mDCs and 12 of which were upregulated only in tDCs. Additionally, 10 genes were overexpressed or equally expressed in both tDCs and mDCs. Scin (tDC-specific genes) and Orm1, Pdlim4 and Enpp2 (mDC-specific genes) were validated by real-time qRT-PCR. Taken together, these results clearly show that tDCs and mDCs can be identified according to their expression of specific gene markers.

IL-35 and Autoimmunity: a Comprehensive Perspective.

Interleukin 35 (IL-35) is the most recently identified member of the IL-12 family of cytokines and offers the potential to be a target for new therapies for autoimmune, inflammatory, and infectious diseases. Similar to other members of the IL-12 family including IL-12, IL-23, and IL-27, IL-35 is composed of a heterodimer of α and ß chains, which in the case of IL-35 are the p35 and Epstein-Barr virus-induced gene 3 (EBI3) proteins. However, unlike its proinflammatory relatives, IL-35 has immunosuppressive effects that are mediated through regulatory T and B cells. Although there are limited data available regarding the role of IL-35 in human autoimmunity, several murine models of autoimmunity suggest that IL-35 may have potent effects in regulating immunoreactivity via IL-10-dependent mechanisms. We suggest that similar effects are operational in human disease and IL-35-directed therapies hold significant promise. In particular, we emphasize that IL-35 has immunosuppressive ability that are mediated via regulatory T and B cells that are IL-10 dependent. Further, although deletion of IL-35 does not result in spontaneous breach of tolerance, recombinant IL-35 can improve autoimmune responses in several experimental models.

Treatment of macular degeneration using embryonic stem cell-derived retinal pigment epithelium: preliminary results in Asian patients.

Embryonic stem cells hold great promise for various diseases because of their unlimited capacity for self-renewal and ability to differentiate into any cell type in the body. However, despite over 3 decades of research, there have been no reports on the safety and potential efficacy of pluripotent stem cell progeny in Asian patients with any disease. Here, we report the safety and tolerability of subretinal transplantation of human embryonic-stem-cell (hESC)-derived retinal pigment epithelium in four Asian patients: two with dry age-related macular degeneration and two with Stargardt macular dystrophy. They were followed for 1 year. There was no evidence of adverse proliferation, tumorigenicity, ectopic tissue formation, or other serious safety issues related to the transplanted cells. Visual acuity improved 9-19 letters in three patients and remained stable (+1 letter) in one patient. The results confirmed that hESC-derived cells could serve as a potentially safe new source for regenerative medicine.

Bone erosion is associated with reduction of circulating endothelial progenitor cells and endothelial dysfunction in rheumatoid arthritis.

OBJECTIVE: To identify factors influencing endothelial progenitor cell (EPC) counts in patients with rheumatoid arthritis (RA). METHODS: The number of circulating CD34+/ vascular endothelial growth factor receptor 2-positive EPCs was measured in 126 RA patients and 46 non-RA control patients. Endothelial function was assessed by brachial flow-mediated dilation (FMD). Serum CXCL12 concentrations were determined using an enzyme-linked immunosorbent assay. EPCs and FMD were measured at baseline and after 24 weeks of anti-tumor necrosis factor (TNF) therapy in 29 patients with active RA. RESULTS: The numbers of circulating EPCs were significantly lower in the RA patients than in the non-RA controls. In multivariate analysis, older age, reduced levels of high-density lipoprotein cholesterol, and higher bone erosion scores were independent risk factors for reduced EPC counts in RA patients. Serum CXCL12 levels correlated negatively with EPC counts, but positively with bone erosion scores. FMD was impaired in RA patients, and a decreased FMD in RA was closely associated with a higher bone erosion score and a reduced EPC count. In addition, EPC counts were restored by anti-TNF therapy, and this increase was paralleled by improvement in FMD. Interestingly, restoration of EPC counts was attenuated in patients with higher bone erosion scores than in those with lower scores, despite similar levels of improvement in disease activity. CONCLUSION: The numbers of circulating EPCs in RA patients are reduced and are inversely correlated with serum levels of CXCL12. Reduced EPC counts are closely associated not only with bone erosion, but also with endothelial dysfunction.

The efficacy of tramadol/acetaminophen combination tablets (Ultracet®) as add-on and maintenance therapy in knee osteoarthritis pain inadequately controlled by nonsteroidal anti-inflammatory drug (NSAID).

The purpose of this study is to compare the efficacy of tramadol 37.5 mg/acetaminophen 325 mg combination tablets (tramadol/APAP) with that of nonsteroidal anti-inflammatory drugs (NSAIDs) as maintenance therapy following tramadol/APAP and NSAID combination therapy in knee osteoarthritis (OA) pain which was inadequately controlled by NSAIDs. Subjects with knee OA for over 1 year and moderate pain (numerical rating scale [NRS] ≥5) despite at least 4 weeks' NSAID therapy (meloxicam 7.5 mg or 15 mg qd or aceclofenac 100 mg bid) received tramadol/APAP add-on (combination with NSAID) for 4 weeks. Thereafter, subjects with significant pain improvement (NRS <4) were randomized to receive either tramadol/APAP or NSAID for 8 weeks. On days 29 and 57, Western Ontario and McMaster Universities (WOMAC) OA index score was measured. Secondary measures included pain intensity (NRS), pain relief score, and subjects' and investigators' overall medication assessments. Of 143 subjects enrolled, 112 completed the 4-week tramadol/APAP and NSAID combination phase and 97 (67.8%) experienced significant pain improvement. Of the 97 subjects randomized, 36 in tramadol/APAP group and 47 in NSAID group completed the 8-week comparator study. On days 29 and 57, WOMAC scores and pain intensities did not increase in both groups compared to measurements immediately after the combination therapy. At these two time points, there were no significant differences in WOMAC scores, pain intensities, and other secondary measures between the two groups. Overall adverse event rates were similar in both groups. Tramadol/APAP add-on significantly improved knee OA pain which had been inadequately controlled by NSAIDs. In those subjects who showed favorable response to tramadol/APAP and NSAID combination therapy, both tramadol/APAP and NSAIDs were effective at maintaining the pain-reduced state and there was no significant difference in efficacy between tramadol/APAP and NSAIDs.

Pararenal retroperitoneal Castleman's disease mimicking systemic lupus erythematosus.

A 41-year-old man diagnosed initially as probable systemic lupus erythematosus (SLE) visited our hospital complaining of a persistent painful oral ulcer and multiple spots like coffee beans on his trunk. Antibodies except for anti-dsDNA and anti-histone antibodies and other serologies were negative. Conventional cytotoxic and immunomodulatory agents did not have any effect on these lesions. Computed tomography for evaluating persistent dry cough incidentally showed a huge mass in the left mid-retroperitoneum. Surgical treatment was done and the final diagnosis was Castleman's disease (CD). CD is a relatively rare disorder characterized by a massive non-malignant tumor of lymphoid tissues, with unknown etiology. It commonly presents as a localized soft tissue mass within the mediastinum or neck, and rarely in the retroperitoneal space. Since some cases of CD may share systemic, immune and histopathologic features of autoimmune disease, exact diagnosis is difficult to make based on the clinical and laboratory clues alone. We report herein an unusual case with pararenal retroperitoneal CD mimicking SLE.

The role of macrophages in the in vitro generation of extracellular DNA from apoptotic and necrotic cells.

Cell death is a ubiquitous process that occurs by apoptosis or necrosis depending on the triggering event. While apoptotic and necrotic cells differ biochemically, both are cleared by macrophages for elimination. The process is very efficient, although DNA can appear in the blood in various clinical conditions associated with cell death. To define the role of macrophages in the generation of extracellular DNA, in vitro experiments were performed, assessing the release of DNA into the media of apoptotic or necrotic Jurkat cells cultured with RAW264.7 or J774 macrophage cell lines. DNA was measured by a fluorimetric assay using the dye PicoGreen. In these experiments, while necrotic cells alone did not release DNA, in the presence of macrophages, significant amounts of DNA appeared in the medium. This DNA contained sequences from the Jurkat cells and had reduced molecular weight in comparison to cellular DNA. Furthermore, coculture of macrophages with enucleated necrotic Jurkat cells did not release DNA, suggesting that the DNA came from the dead cell. In contrast, Jurkat cells made apoptotic by treatment with either staurosporine or etoposide spontaneously released DNA, while coculture with macrophages caused a decrease in the DNA released. With apoptotic cells, the DNA in the medium showed low molecular weight and laddering whether or not macrophages were present. Together, these results indicate that macrophages play an important role in the generation of extracellular DNA from dead and dying cells, with the effect dependent on how the cell died.

Elevated vascular endothelial growth factor in systemic sclerosis.

OBJECTIVE: To determine the serum levels of vascular endothelial growth factor (VEGF) in patients with systemic sclerosis (SSc) and to search for relationships between its serum levels and the clinical manifestations. METHODS: Serum levels of VEGF in patients with SSc and healthy controls were determined by ELISA. At the time of blood sampling, individual organ involvement was assessed, and a video microscope and PC based image processing were used to visualize nailfold capillaries and to quantify capillary density. RESULTS: Serum levels of VEGF in 48 patients with SSc were significantly higher than in 30 controls (432 +/- 356 vs 91 +/- 64 pg/ml; p < 0.001). Patients with diffuse cutaneous SSc (n = 21) had higher levels of serum VEGF than those with limited cutaneous SSc (n = 27) (432 +/- 356 vs 135 +/- 127 pg/ml; p < 0.001). Serum VEGF levels correlated well with the extent of skin sclerosis, as determined by modified Rodnan skin score (r = 0.656, p < 0.001) and serum TGF-beta levels (r = 0.530, p < 0.001). In particular, serum VEGF levels were inversely correlated with the capillary density of nailfold (r = -0.649, p < 0.001). However, no significant differences were found in the serum levels of VEGF between patients with systemic organ involvement and those without. CONCLUSION: The extent of skin sclerosis may contribute to the elevation of serum VEGF and high VEGF levels may serve as a surrogate indicator of capillary damage in SSc.