Search

Objective. IL-9 has been shown to be upregulated before the clinical onset of articular disease in RA. The exact role of IL-9 and Th9 cells in RA, however, has not yet been adequately studied. The aim of this study was to evaluate the expression of IL-9 and IL-9-expressing cells in RA patients. Methods. IL-9, IL-9R, PU.1, IL-9, thymic stromal lymphopoietin (TSLP), IL-4 and TGF-α expression was assessed by real-time-PCR in the synovial tissues of RA and OA patients. IL-9, IL-9R, IL-4, TSLP and TGF-β were also investigated by immunohistochemistry. Peripheral CD4+ T cell subsets were studied by flow cytometry analysis before and after incubation with citrullinated peptides. Results. IL-9 was overexpressed in RA synovial tissues and correlated with the degree of histological organization of B and T cells in ectopic lymphoid structures. The majority of IL-9-producing cells were identified as CD3+ cells. Increased mRNA and protein expression of IL-9R, IL-4, TSLP and TGF-β was also observed in RA synovial tissue. Blood peripheral Th9 cells were expanded by citrullinated peptides. Conclusion. These results indicate that Th9 cells and IL-9 were frequently detected in peripheral blood mononuclear cells and synovia of RA patients. A possible pathogenic role for Th9 in RA is discussed. [ABSTRACT FROM AUTHOR]

Objective. GCA is a large- and medium-vessel arteritis characterized by a range of histological patterns of vascular wall injury. The aim of this study was to immunologically characterize the various histological patterns of GCA. Methods. Thirty-five consecutive patients with biopsy-proven GCA and 15 normal controls were studied. IL-8, IL-9, IL-9R, IL-17, IL-4, TGF-β and thymic stromal lymphopoietin expression was evaluated by RT-PCR and immunohistochemistry on artery biopsy specimens. Confocal microscopy was used to characterize the phenotypes of IL-9-producing and IL-9R-expressing cells. Five additional patients who had received prednisone when the temporal artery biopsy was performed were also enrolled to evaluate the effect of glucocorticoids on IL-9 and IL-17 expression. Results. IL-17 overexpression was observed mainly in arteries with transmural inflammation and vasa vasorum vasculitis. IL-9 overexpression and Th9 polarization predominated in arteries with transmural inflammation and small-vessel vasculitis. The tissue expression of both IL-9 and IL-17 was correlated with the intensity of the systemic inflammatory response. IL-4, TGF-β and thymic stromal lymphopoietin, which are involved in the differentiation of Th9 cells, were overexpressed in arteries with transmural inflammation and small-vessel vasculitis. IL-9R was also overexpressed in GCA arteries with transmural inflammation and was accompanied by increased expression of IL-8. Conclusion. Herein we provide the first evidence that distinct populations of potentially autoreactive T cells, expressing different cytokines (Th17 vs Th9), characterize patients with particular histological subsets of GCA and may thus contribute to the heterogeneity of tissue lesions observed in these patients. [ABSTRACT FROM AUTHOR]

Objective. Human umbilical cord Wharton jelly-derived mesenchymal stem cells (hUCMS) are easy to retrieve in bulk. They may interact with immune cells by either cell contact or soluble factors. Little evidence is currently available on potential therapeutic application of hUCMS to systemic autoimmune disorders such as primary SS (pSS). We have recently developed an endotoxin-free alginate gel that can be used to microencapsulate different cell types for graft into non-immunosuppressed hosts. We aimed to assess the in vitro effects of IFN-γ-pretreated microencapsulated (CpS)-hUCMS on T cells of pSS.Methods. Ten pSS patients and 10 healthy donors were selected. Peripheral blood mononuclear cells (PBMCs) were obtained from venous blood to establish co-cultures with CpS-hUCMS. Lymphocyte proliferation and phenotypic analysis was performed by flow cytometry and real-time PCR on IFN-γ-pretreated hUCMS was performed before PBMCs co-culture.Results. We found that CpS-hUCMS suppress pSS T cell proliferation and restore the Treg/Th17 ratio, thereby possibly positively impacting the pSS disease process.Conclusion. We have developed a new biohybrid drug delivery system that now waits for clinical application in autoimmune diseases, including pSS. [ABSTRACT FROM PUBLISHER]

Objective. The B cell chemoattractant chemokine ligand 13 (CXCL13) is emerging as a new biochemical marker in RA. This study was undertaken to dissect the relationship between CXCL13 expression levels in the synovium and clinico-pathological variables relevant to RA pathogenesis and outcome.Methods. Synovial tissues from 71 RA patients were evaluated by immunohistochemistry. Thirty paired samples were used for comparative gene expression analysis by quantitative real-time PCR. CXCL13 levels were analysed in relation to cellular, molecular and clinical features of inflammation, lymphocyte activation and joint damage.Results. In patients with early disease (<12 months duration), CXCL13 expression correlated significantly with synovial markers of local disease activity and systemic inflammation. Such correlation was less evident in established RA. Notably, the association with lymphocyte infiltration and with expression of B/T cell–related activation and proliferation genes, such as activation-induced cytidine deaminase, IFN-γ and IL-2, remained highly significant independent of disease duration and local disease activity. Patients featuring the highest levels of CXCL13 were more frequently ACPA positive and IgG ACPA titres were increased in the high CXCL13 expression group. Furthermore, the frequency of erosive disease on radiographs was significantly higher in the upper tertile of CXCL13 expression (P = 0.01 with adjustment for disease duration and ACPA). Accordingly, synovial CXCL13 and the local receptor activator of nuclear factor κB ligand (RANKL)/osteoprotegerin (OPG) ratio significantly co-varied (ρ = 0.52, P < 0.01), independent of the level of local inflammation.Conclusion. Synovial CXCL13 appears to be a marker of a more severe pattern of RA disease, characterized by increased lymphocyte activation and bone remodelling beyond the level of conventional markers of inflammation. [ABSTRACT FROM PUBLISHER]

Objective. The aim of this study was to evaluate the role of rituximab (RTX) in modulating the expression of the IL-17/IL-23 pathway in the salivary glands (SGs) of patients with primary SS (pSS).Methods. Consecutive SG biopsies were obtained from 15 patients with pSS before and after 1 year of RTX therapy. The SG expression of IL-17, IL-23p19 and p-STAT3 was evaluated by immunohistochemistry at baseline and after RTX therapy. The role of mast cells in pSS patients in modulating the Th17 response and the immunologic effect of RTX on mast cells were also studied in in vitro experiments.Results. IL-17 was overexpressed in the SGs of patients with pSS mainly by infiltrating T cells and mast cells. After RTX therapy, the SG expression of IL-17, but not of IL-23p19 and p-STAT3, was significantly reduced and was accompanied by the depletion of tissue mast cells. In in vitro experiments with heterologous peripheral lymphocytes RTX significantly induced the apoptosis of isolated mast cells. Finally, mast cells isolated from peripheral blood mononuclear cells of pSS patients in vitro significantly increased Th17 lymphocytes.Conclusion. RTX acts on pSS patients by globally reducing the expression of IL-17 and specifically inducing a pronounced apoptotic depletion of mast cells. [ABSTRACT FROM PUBLISHER]

Objective. CD4+CD25lowGITR+ T lymphocytes expressing FoxP3 and showing regulatory function have been recently described in healthy donors (HD). The objective of the study was to investigate their presence and role in patients with primary SS (pSS).Methods. CD4+CD25lowGITR+ cells circulating in peripheral blood (PB) of patients with pSS were isolated by MACS technique, their phenotype was studied by flow cytometry and real-time PCR, and their function was studied by in vitro co-culture. CD4+CD25lowGITR+ cells infiltrating salivary glands (SGs) were revealed by immunohistochemistry.Results. Results indicated that conventional CD4+CD25high regulatory T cells (Tregs) are decreased, whereas CD4+CD25lowGITR+ cells are expanded in the PB of pSS as compared with HD. Phenotypic analysis demonstrated that CD4+CD25lowGITR+ cells display Treg markers, including FoxP3, TGF-β and IL-10, and functional experiments demonstrated that they exert a strong inhibitory activity against autologous effector cells. CD4+CD25lowGITR+ cells were detectable in great number in the SG inflammatory infiltrate. Interestingly, PB CD4+CD25lowGITR+ cell expansion was evident only in patients with inactive disease, while conventional CD4+CD25high Treg number was not associated with disease activity.Conclusion. The present data demonstrate that circulating CD4+ cells expressing GITR, but with low levels of CD25 (CD4+CD25lowGITR+), are detectable in pSS patients. These cells, displaying Treg phenotype and function, are present in SG inflamed tissues and are expanded in the PB of subjects with inactive disease. Data suggest that the expansion of CD4+CD25lowGITR+ cells in pSS may represent a counter-regulatory attempt against autoimmune-driven inflammation and may provide a new target for future treatment strategies. [ABSTRACT FROM PUBLISHER]

Objective. Primary SS is characterized by an increased risk of lymphoma in patients with prelymphomatous manifestations (i.e. myoepithelial sialadenitis or mixed cryoglobulinaemia). Serum B-lymphocyte stimulator (s-BLyS) levels in SS-related B-cell lymphoproliferative disorders were studied by integrating the results with the disease activity score and with molecular analyses of B-cell expansion in the salivary glands.Methods. Seventy-six primary SS patients (with or without lymphoma or prelymphomatous manifestations), 56 HCV-related cryoglobulinaemic vasculitis patients and 55 controls were studied. s-BLyS and molecular analyses of B-cell expansion in the salivary gland tissues were performed. Patients with SS and persistent parotid swelling underwent parotid biopsy.Results. s-BLyS differed between SS subgroups, higher levels being documented in patients with lymphoma or prelymphomatous manifestations vs SS without [1.85 (0.45–4.12) ng/ml vs 1.12 (0.56–1.98) ng/ml; P < 0.0001]. s-BLyS levels significantly correlated with the European League Against Rheumatism (EULAR) SS disease activity index (r = 0.62, P < 0.0001, Spearman’s test). Clonal B-cell expansion in the salivary glands, but not polyclonal B-cell expansion, was associated with higher s-BLyS levels [1.98 (0.45–4.12) ng/ml vs 1.15 (0.56–3.25) ng/ml; P = 0.013)].Conclusion. Higher s-BLyS levels and tissue clonal B-cell expansion characterize SS with B-cell lymphoproliferative disorders, even at prelymphomatous stages. This subgroup of SS patients showed the highest EULAR SS disease activity index scores. This represents a biologic rationale for targeting both clonal B-cell expansion and s-BLyS overproduction in SS. [ABSTRACT FROM PUBLISHER]

Objectives. Peroxisome proliferator-activated receptor-gamma (PPARγ) is expressed by different cell types in the joints and plays a relevant anti-inflammatory role in various diseases. This pilot study aimed to evaluate PPARγ expression in monocytes/macrophages isolated from RA patients as compared with healthy subjects, the relationships between PPARγ expression, MMP-9 activity and disease, and the influence of therapy with anti-rheumatic drugs on these parameters.Methods. Thirty RA patients of both sexes (treated with CSs and MTX, mainly) and 15 healthy volunteers were enrolled in this study. Disease severity was evaluated by the 28-joint disease activity score (DAS-28). Monocytes and monocyte-derived macrophages (MDMs) were isolated by standard procedures. PPARγ protein and mRNA expression were assessed by immunoblotting and real-time PCR, respectively; MMP-9 activity was determined by gelatin zymography. Moreover, we checked the ability of 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ, a PPARγ agonist), MTX and methylprednisolone (MP) to affect PPARγ expression and lipopolysaccharide (LPS)-induced MMP-9 activity.Results. Monocytes/MDMs from RA patients have significantly enhanced PPARγ expression (both protein and mRNA) and MMP-9 activity as compared with healthy donors. Interestingly, cells from patients with less active disease (DAS-28 <3.2) present higher PPARγ protein expression and lower MMP-9 activity than RA patients with DAS-28 >3.2. At therapeutic concentrations, MTX and MP increase in vitro PPARγ protein expression and inhibit LPS-induced MMP-9 activity.Conclusion. PPARγ expression in human monocytes/MDMs could represent an indicator of disease activity and therapy efficacy in RA because patients with a DAS-28 score <3.2 show the highest expression. [ABSTRACT FROM AUTHOR]

Objective. The relationship of cryoglobulinaemia with lymphoproliferation of mucosa-associated lymphoid tissue (MALT) as risk factors for lymphoma evolution in SS remains to be clarified. The different biologic background of SS-related cryoglobulinaemia as compared with cryoglobulinaemia linked to HCV infection was clarified by different clinical and biologic approaches.Methods. B-cell clonal expansion was analysed in the bone marrow of 27 consecutive cases with primary SS and mixed cryoglobulinaemia, HCV unrelated, in comparison with 55 HCV-related patients with cryoglobulinaemic vasculitis (CV) without SS. The results were related to the possible occurrence and localization of B-cell lymphoma in the single case. Secondly, the prevalence of mixed cryoglobulinaemia was investigated in 41 unselected patients with primary SS showing either parotid myoepithelial sialadenitis (MESA) or a frank B-cell non-Hodgkin's lymphoma. Thirdly, the levels of serum cryoglobulins and RF were followed in one patient with primary SS, CV and parotid B-cell lymphoma of MALT after bilateral subtotal parotidectomy.Results. A polyclonal pattern of B expansion in the bone marrow was significantly more frequent in SS-related (19/27 cases) than in HCV-related cryoglobulinaemia (19/55) (P = 0.003). Cryoglobulins were positive in a fraction of patients with SS and malignant lymphoma or with parotid MESA (13/18 and 7/23, respectively), whereas MALT involvement by the lymphoproliferative disorder was the rule. Finally, the levels of serum cryoglobulins and RF markedly decreased in the SS patient undergoing bilateral subtotal parotidectomy.Conclusion. Lymphoproliferation of MALT appears as the biologic background of cryoglobulinaemia in SS, differently from HCV-related cryoglobulinaemia. [ABSTRACT FROM PUBLISHER]