Raquel Celis

Ectopic lymphoid neogenesis in psoriatic arthritis

Background: Ectopic lymphoid neogenesis (LN) occurs in rheumatoid synovium, where it is thought to drive local antigen-dependent B cell development and autoantibody production. This process involves the expression of specific homing chemokines and the development of high endothelial venules (HEV). Objective: To investigate whether these mechanisms occur in psoriatic arthritis (PsA) synovium, where autoantibodies have not been described and the organisation and function of B cells is not clear, and to analyse their clinical correlates. Methods: Arthroscopic synovial biopsy specimens from patients with PsA before and after tumour necrosis factor α blockade were characterised by immunohistochemical analysis for T/B cell segregation, peripheral lymph node addressin (PNAd)-positive HEV, and the expression of CXCL13, CCL21 and CXCL12 chemokines in relation to the size of lymphoid aggregates. Results: Lymphoid aggregates of variable sizes were observed in 25 of 27 PsA synovial tissues. T/B cell segregation was often observed, and was correlated with the size of lymphoid aggregates. A close relationship between the presence of large and highly organised aggregates, the development of PNAd+ HEV, and the expression of CXCL13 and CCL21 was found. Large organised aggregates with all LN features were found in 13 of 27 tissues. LN in PsA synovitis was not related to the duration, pattern or severity of the disease. The synovial LN pattern remained stable over time in persistent synovitis, but a complete response to treatment was associated with a regression of the LN features. Conclusions: LN occurs frequently in inflamed PsA synovial tissues. Highly organised follicles display the characteristic features of PNAd+ HEV and CXCL13 and CCL21 expression, demonstrating that the microanatomical bases for germinal centre formation are present in PsA. The regression of LN on effective treatment indicates that the pathogenic and clinical relevance of these structures in PsA merits further investigation.

Clinical significance of synovial lymphoid neogenesis and its reversal after anti-tumour necrosis factor α therapy in rheumatoid arthritis

Objective: To investigate the clinical significance of lymphoid neogenesis (LN) in rheumatoid arthritis (RA), the clinicopathological correlates of this process and its evolution after anti-tumour necrosis factor (TNF)α therapy in a large series of synovial tissues were analysed. Methods: Arthroscopic synovial biopsies from 86 patients with RA were analysed by immunohistochemistry. LN was defined as the presence of large aggregates of lymphocytes with T/B cell compartmentalisation and peripheral node addressin (PNAd) positive high endothelial venules. Clinical variables at baseline and after prospective follow-up were compared in LN positive and negative RA subsets. The evolution of LN and its correlation with the clinical course in a subgroup of 24 patients that underwent a second arthroscopic biopsy after anti-TNFα therapy was also analysed. Results: LN was present in 49% of RA synovial tissues. Patients with LN had a significantly higher disease duration and a higher previous use of anti-TNFα agents. During prospective follow-up, the proportion of patients achieving good or moderate European League Against Rheumatism (EULAR) 28-joint Disease Activity Score (DAS28) responses was significantly lower in patients who were LN positive despite a significantly higher use of anti-TNFα agents. By multivariate logistic regression analysis, LN remained as an independent negative predictor of response to therapy. In the subgroup of patients rebiopsied after anti-TNFα therapy, reversal of LN features occurred in 56% of the patients and correlated with good clinical responses. Conclusions: Synovial LN in RA predicts a lower response to therapy. LN features can be reversed after a short period of anti-TNFα therapy in parallel to good clinical responses.

Influence of variants of Fcγreceptors IIA and IIIA on the ACR and EULAR responses to anti-TNFα therapy in rheumatoid arthritis

Objective: Fcγ receptor (FcγR) polymorphism influences the affinity of the receptor for Ig, which may, in turn, affect the efficacy of Ig-based therapies. The relationship between functional single nucleotide polymorphisms (SNP) of the FCGR2A and FCGR3A genes and the response to anti-tumour necrosis factor (TNF)α therapy (infliximab) in patients with rheumatoid arthritis (RA) was assessed. Methods: A total of 91 patients with RA (89% female; 76.7% rheumatoid factor (RF) positive) starting therapy with infliximab were evaluated at 0, 6 and 30 weeks using the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) response criteria and the 28-joint Disease Activity Score (DAS28) was evaluated using three parameters, including C-reactive protein (CRP) (DAS28 3v-CRP) changes during the follow-up. Genotyping of FCGR2A-R131H and FCGR3A-F158V polymorphisms was performed by allele-specific PCR and PCR sequence-based typing, respectively. The χ2 and Fisher exact tests were used to show differences in the outcome variables, and analysis of variance (ANOVA) to analyse the evolution of DAS28 3v-CRP. A generalised linear models multivariable analysis was also performed. Results: At week 6 of follow-up, the proportion of patients achieving 50% improvement as per ACR criteria (ACR50) and EULAR good responses were significantly higher among homozygotes of the low affinity FCGR3A allele (FF: 24.1% and VV-VF:2.2%; p = 0.003 and FF: 44.8% and VV-VF: 22.9%; p = 0.040, respectively). At week 30, homozygotes of the low affinity FCGR2A allele had a better ACR20 response (RR: 60% and HH-RH: 33.3%; p = 0.035). Changes in DAS28 3v-CRP during follow-up were consistent with those observed in ACR and EULAR responses. Conclusions: The response to anti-TNFα treatment with infliximab in patients with RA is influenced by the FCGR2A and FCGR3A genotypes. This effect is observed at different times in the follow-up (6 and 30 weeks, respectively) indicating the dynamic nature of the FcγR versus Ig interaction.

Clinical significance of synovial lymphoid neogenesis and its reversal after anti-TNF-α therapy in rheumatoid arthritis

Objective: To investigate the clinical significance of lymphoid neogenesis (LN) in rheumatoid arthritis (RA), the clinicopathological correlates of this process and its evolution after anti-tumour necrosis factor (TNF)α therapy in a large series of synovial tissues were analysed. Methods: Arthroscopic synovial biopsies from 86 patients with RA were analysed by immunohistochemistry. LN was defined as the presence of large aggregates of lymphocytes with T/B cell compartmentalisation and peripheral node addressin (PNAd) positive high endothelial venules. Clinical variables at baseline and after prospective follow-up were compared in LN positive and negative RA subsets. The evolution of LN and its correlation with the clinical course in a subgroup of 24 patients that underwent a second arthroscopic biopsy after anti-TNFα therapy was also analysed. Results: LN was present in 49% of RA synovial tissues. Patients with LN had a significantly higher disease duration and a higher previous use of anti-TNFα agents. During prospective follow-up, the proportion of patients achieving good or moderate European League Against Rheumatism (EULAR) 28-joint Disease Activity Score (DAS28) responses was significantly lower in patients who were LN positive despite a significantly higher use of anti-TNFα agents. By multivariate logistic regression analysis, LN remained as an independent negative predictor of response to therapy. In the subgroup of patients rebiopsied after anti-TNFα therapy, reversal of LN features occurred in 56% of the patients and correlated with good clinical responses. Conclusions: Synovial LN in RA predicts a lower response to therapy. LN features can be reversed after a short period of anti-TNFα therapy in parallel to good clinical responses.

Immature Blood Vessels in Rheumatoid Synovium Are Selectively Depleted in Response to Anti-TNF Therapy

Background Angiogenesis is considered an important factor in the pathogenesis of Rheumatoid Arthritis (RA) where it has been proposed as a therapeutic target. In other settings, active angiogenesis is characterized by pathologic, immature vessels that lack periendothelial cells. We searched for the presence of immature vessels in RA synovium and analyzed the dynamics of synovial vasculature along the course of the disease, particularly after therapeutic response to TNF antagonists. Methodology/Principal Findings Synovial arthroscopic biopsies from RA, osteoarthritis (OA) and normal controls were analyzed by double labeling of endothelium and pericytes/smooth muscle mural cells to identify and quantify mature/immature blood vessels. To analyze clinicopathological correlations, a cross-sectional study on 82 synovial biopsies from RA patients with variable disease duration and severity was performed. A longitudinal analysis was performed in 25 patients with active disease rebiopsied after anti-TNF-α therapy. We found that most RA synovial tissues contained a significant fraction of immature blood vessels lacking periendothelial coverage, whereas they were rare in OA, and inexistent in normal synovial tissues. Immature vessels were observed from the earliest phases of the disease but their presence or density was significantly increased in patients with longer disease duration, higher activity and severity, and stronger inflammatory cell infiltration. In patients that responded to anti-TNF-α therapy, immature vessels were selectively depleted. The mature vasculature was similarly expanded in early or late disease and unchanged by therapy. Conclusion/Significance RA synovium contains a significant fraction of neoangiogenic, immature blood vessels. Progression of the disease increases the presence and density of immature but not mature vessels and only immature vessels are depleted in response to anti-TNFα therapy. The different dynamics of the mature and immature vascular fractions has important implications for the development of anti-angiogenic interventions in RA.

Distinct synovial immunopathology in Behçet disease and psoriatic arthritis.

IntroductionThe aim of the study was to investigate synovial immunopathology differences between early Behçet disease (BD) and psoriatic arthritis (PsA).MethodsNeedle arthroscopy of an inflamed knee joint was performed in patients with early untreated BD (n = 8) and PsA (n = 9). Synovial fluid (SF) was collected for cytokines, perforin, and granzyme analysis. Eight synovial biopsies per patient were obtained for immunohistochemical analysis of the cellular infiltrate (T cells, natural killer cells, macrophages, B cells, plasma cells, mast cells, and neutrophils), blood vessels as well as expression of perforin and granzyme. The stained slides were evaluated by digital image analysis.ResultsThe global degree of synovial inflammation was similar in the two types of arthritis. In the analysis of the innate immune cell infiltration, there was a striking neutrophilic inflammation in BD synovitis whereas PsA displayed significantly higher numbers of cells positive for c-kit, a marker of mast cells. As for lymphocytes, CD3+ T cells, but neither CD20+ B cells nor CD138+ plasma cells, were significantly increased in BD versus PsA. Further analysis of the T-lymphocyte population showed no clear shift in CD4/CD8 ratio or Th1/Th2/Th17 profile. The SF levels of perforin, an effector molecule of cytotoxic cells, displayed a significant four- to fivefold increase in BD.ConclusionsThis systematic comparative analysis of early untreated synovitis identifies neutrophils and T lymphocytes as important infiltrating cell populations in BD. Increased levels of perforin in BD suggest the relevance of cytotoxicity in this disease.

Effects of polymorphisms in TRAILR1 and TNFR1A on the response to anti-TNF therapies in patients with rheumatoid and psoriatic arthritis

OBJECTIVES As the role of polymorphisms in death receptors (DRs) such as Tumor Necrosis Factor-related Apoptosis-inducing Ligand Receptor 1 (TRAIL-R1) and Tumor Necrosis Factor Receptor 1A (TNF-R1A) on the response to anti-TNF therapy remains unknown, we evaluated the association between TRAILR1 and TNFR1A gene polymorphisms (rs20575/C626G and rs767455/G36A) and the pharmacogenetics of patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) treated with TNFα blockers. METHODS One hundred and forty-five patients (90 RA and 55 PsA) treated with anti-TNFα therapy (RA: 75 infliximab, 8 etanercept, 7 adalimumab. PsA: 27 infliximab, 19 etanercept, 9 adalimumab) were genotyped for TRAILR1 and TNFR1A polymorphisms by allelic discrimination. The response to anti-TNFα was assessed by EULAR criteria. RESULTS In RA, the TRAILR1 CC genotype was associated with a better response after 3 and 6 months of anti-TNFα treatment (CC: 91.7% vs. CG/GG: 62.2%; P=0.019, and CC: 82.6% vs. CG/GG: 56.1%; P=0.019, respectively). Similar results were observed in only infliximab-treated RA patients. With respect to the TNFR1A polymorphism, there was an association between the AA genotype and a poorer response at 3 months in RA patients (AA: 39.3% vs. AG/GG 19.0%; P=0.04). In PsA, TRAILR1 CC genotype was only associated with EULAR response to infliximab at 6 months (CC: 71.4% vs CG/GG: 50%P=0.048). In contrast to RA, the TNFR1 polymorphism in PsA was associated with a better response at 3 months (AA 88% vs AG/GG 58.9%; P=0.04). CONCLUSIONS This study provides the first evidence that a polymorphism in TRAILR1 influences the response to anti-TNFα therapy in RA and also suggests that TNFR1A polymorphism may have opposing effects on the response to anti-TNFα in RA and PsA.

Synovial cytokine expression in psoriatic arthritis and associations with lymphoid neogenesis and clinical features

IntroductionPsoriatic arthritis (PsA) is an autoantibody-negative immune-mediated disease in which synovial lymphoid neogenesis (LN) occurs. We determined whether LN is associated with specific patterns of inflammatory cytokine expression in paired synovial tissue (ST) and fluid (SF) samples and their potential correlation with the clinical characteristics of PsA.MethodsST and paired SF samples were obtained from the inflamed knee of PsA patients. ST samples were immunostained with CD3 (T cell), CD20 (B cell), and MECA-79 (high endothelial vessels). Total ST mRNA was extracted, and the gene expression of 21 T-cell-derived and proinflammatory cytokines were measured with quantitative real-time PCR. SF concentrations of Th1, Th2, Th17, and proinflammatory cytokines were determined with the Quantibody Human Th17 Array. Clinical and biologic data were collected at inclusion and after a median of 27 months of follow-up.ResultsTwenty (43.5%) of 46 patients had LN. Only two genes showed differences (Wilcoxon test, P < 0.06) in ST between LN-positive and LN-negative patients: interleukin-23A (IL-23A) (P = 0.058) and transforming growth factor-beta (TGF-β1) (P = 0.050). IL-23A expression was higher, and TGF-β1 expression was lower in LN-positive patients. ST IL-15 mRNA showed a nonsignificant trend toward higher expression in LN-positive patients, and SF IL-15 protein levels were significantly higher in LN-positive patients (P = 0.002). In all PsA patients, IL-23A mRNA expression correlated with C-reactive protein (CRP) (r = 0.471; P = 0.001) and swollen-joint count (SJC) (r = 0.350; P = 0.018), whereas SF levels of IL-6 and CC chemokine-ligand 20 (CCL-20) correlated with CRP levels (r = 0.377; P = 0.014 and r = 0.501; P < 0.0001, respectively).ConclusionsThese findings suggest differences in the cytokine profile of PsA patients with LN, with a higher expression of IL-23A and IL-15 and a lower expression of TGF-β1. In the entire group of patients, IL-23 ST expression and CCL20 SF levels strongly correlated with markers of disease activity. This cytokine pattern was not accompanied by gross clinical or biologic differences between LN-positive and -negative patients. Taken together, these results suggest a role of the IL-17/IL-23 cytokine axis in synovial LN in PsA.

Synovial fibroblast hyperplasia in rheumatoid arthritis: Clinicopathologic correlations and partial reversal by anti–tumor necrosis factor therapy

OBJECTIVE Synovial fibroblast (SF) hyperplasia contributes to the pathogenesis of rheumatoid arthritis (RA), but quantitative information on this process is scarce. This study was undertaken to evaluate the fibroblast-specific marker Hsp47 as a quantitative marker for SFs and to analyze its clinicopathologic correlates and evolution after anti-tumor necrosis factor α (anti-TNFα) therapy. METHODS Synovial biopsy samples were obtained from 48 patients with RA and 20 controls who were healthy or had osteoarthritis (OA). Twenty-five RA patients who had active disease at the time of biopsy underwent a second biopsy after anti-TNFα therapy. Immunolabeling for Hsp47, inflammatory cells, and vascular cell markers was performed. Hsp47-positive lining and sublining fractional areas were quantified, and their correlation with clinicopathologic variables was analyzed. RESULTS In normal and diseased synovial tissue, Hsp47 was specifically and uniformly expressed by lining, sublining, and perivascular fibroblasts. Lining SF area was significantly increased in both RA and late OA tissue compared to normal tissue. Sublining SF area was increased in RA tissue but not in late OA tissue compared to normal tissue. Lining SF area was positively correlated with macrophage density, Disease Activity Score in 28 joints, and RA disease duration. In contrast, sublining SF area was negatively correlated with RA disease duration and activity. A significant reduction in lining SF area but not sublining SF area was observed after anti-TNFα therapy. CONCLUSION Our findings indicate that Hsp47 is a reliable marker for quantifying SFs in human synovial tissue. Our data suggest that lining and sublining SFs undergo different dynamics during the course of the disease. Lining SF expansion parallels the activity and temporal progression of RA and can be partially reversed by anti-TNFα therapy.

Synovial immunopathological changes associated with successful abatacept therapy in a case of severe refractory psoriatic arthritis

The overlapping characteristics of rheumatoid arthritis and psoriatic arthritis (PsA) in terms of T-cell and macrophage infiltration and cytokine patterns suggest that targeted therapies could have a similar effect in both diseases.1 Tumour necrosis factor alpha (TNFα) blockers have shown efficacy in PsA, but a significant proportion of patients do not respond or are intolerant to these drugs.2 In these patients, agents blocking T-cell activation are a potential therapeutic option. Preliminary data have shown efficacy of abatacept in psoriasis vulgaris3 and spondyloarthropathy.4 However, data on the effects of abatacept in PsA are lacking. We describe the clinical and immunopathological effects of abatacept in a patient with PsA refractory to TNFα therapy. A …