Francesco Carubbi

Angiogenesis in rheumatoid arthritis: A disease specific process or a common response to chronic inflammation?

Angiogenesis is the formation of new blood vessels from existing vessels. During RA new blood vessels can maintain the chronic inflammatory state by transporting inflammatory cells to the site of inflammation and supplying nutrients and oxygen to the proliferating inflamed tissue. The increased endothelial surface area also creates an enormous capacity for the production of cytokines, adhesion molecules, and other inflammatory stimuli, simultaneously the propagation of new vessels in the synovial membrane allows the invasion of this tissue supporting the active infiltration of synovial membrane into cartilage and resulting in erosions and destruction of the cartilage. This angiogenic phenotype is promoted by several pro-angiogenic molecules, the most potent of which is vascular endothelial growth factor (VEGF). Although angiogenesis is recognized as a key event in the formation and maintenance the infiltration of synovial membrane during RA, it is unclear whether angiogenesis should be considered a specific feature of the disease or a common inflammation driven process. However the emergence of biological therapies, such as anti TNF blockade, has suggested that there are features of the inflammatory response that are not general but contextual to the specificity of the tissue where inflammation occurs, and point out the relevant role of tissue-resident stromal cells in determining the site at which inflammation occurs and the specific features of chronic inflammation such as that occurs in RA.

Biomarkers of lymphoma in Sjögren's syndrome and evaluation of the lymphoma risk in prelymphomatous conditions: results of a multicenter study.

OBJECTIVES To define the biomarkers associated with lymphoproliferation in primary Sjögrens syndrome (pSS) by distinguishing in separate groups the two best-recognized non-malignant prelymphomatous conditions in pSS, i.e., salivary gland swelling and cryoglobulinemic vasculitis (CV). METHODS A multicenter study was conducted in 5 centres. Patients fulfilled the following criteria: (1) positive AECG criteria for pSS, (2) serum cryoglobulins evaluated, and (3) lack of hepatitis C virus infection. Four groups were distinguished and analysed by multinomial analyses: (1) B-cell non-Hodgkins lymphoma (NHL), (2) CV without lymphoma, (3) salivary swelling without NHL (SW), and (4) pSS patients without NHL or prelymphomatous conditions. RESULTS Six hundred and sixty-one patients were studied. Group 1/NHL comprised 40/661 (6.1%) patients, Group 2/CV 17/661 (2.6%), Group 3/SW 180/661 (27.2%), and Group 4/pSS controls 424/661 (64.1%). Low C4 [relative-risk ratio (RRR) 8.3], cryoglobulins (RRR 6.8), anti-La antibodies (RRR 5.2), and leukopenia (RRR 3.3) were the variables distinguishing Group 1/NHL from Group 4/Controls. As concerns the subset of patients with prelymphomatous conditions, the absence of these biomarkers provided a negative predictive value for lymphoma of 98% in patients with salivary swelling (Group 3/SW). Additional follow-up studies in patients with SW confirmed the high risk of lymphoma when at least 2/4 biomarkers were positive. CONCLUSIONS Lymphoma-associated biomarkers were defined in a multicentre series of well-characterized patients with pSS, by dissecting the cohort in the pSS-associated prelymphomatous conditions. Notably, it was demonstrated for the first time that among the pSS patients with salivary swelling, only those with positive biomarkers present an increased risk of lymphoma evolution.

Scleroderma Mesenchymal Stem Cells display a different phenotype from healthy controls; implications for regenerative medicine

IntroductionVascular involvement is a key feature of Systemic sclerosis (SSc). Although the pericytes/endothelial cells (ECs) cross-talk regulates vessels formation, no evidences about the pericytes contribution to ineffective angiogenesis in SSc are available. Recent findings showed similarities between pericytes and Bone Marrow Mesenchymal Stem Cells (BM-MSCs). Due to difficulties in pericytes isolation, this work explores the possibility to use BM-MSCs as pericytes surrogate, clarifying their role in supporting neo-angiogenesis during SSc.MethodsTo demonstrate their potential to normally differentiate into pericytes, both SSc and healthy controls (HC) BM-MSCs were treated with TGF-β and PDGF-BB. The expression of pericytes specific markers (α-SMA, NG2, RGS5 and desmin) was assessed by qPCR, western blot, and immunofluorescence; chemioinvasion and capillary morphogenesis were also performed. Cell-sorting of BM-MSCs co-cultured with HC-ECs was used to identify a possible change in contractile proteins genes expression.ResultsWe showed that BM-MSCs isolated from SSc patients displayed an up-regulation of α-SMA and SM22α genes and a reduced proliferative activity. Moreover during SSc, both TGF-β and PDGF-BB can specifically modulate BM-MSCs toward pericytes. TGF-β was found interfering with the PDGF-BB effects. Using BM-MSCs/MVECs co-culture system we observed that SSc BM-MSCs improve ECs tube formation in stressed condition, and BM-MSCs, sorted after co-culture, showed a reduced α-SMA and SM22α gene expression.ConclusionsBM-MSCs from SSc patients behave as pericytes. They display a more mature and myofibroblast-like phenotype, probably related to microenvironmental cues operating during the disease. After their co-culture with HC-MVECs, SSc BM-MSCs underwent to a phenotypic modulation which re-programs these cells toward a pro-angiogenic behaviour.

Cardiovascular disease risk burden in primary Sjögren's syndrome: results of a population‐based multicentre cohort study

Systemic autoimmune diseases, in particular systemic lupus erythematosus and rheumatoid arthritis, are characterized by a high risk of premature cardiovascular (CV) events. Disease‐related characteristics and traditional CV disease risk factors may contribute to atherosclerotic damage. However, there are limited data on the risk of overt CV events in primary Sjögrens syndrome (pSS).

The role of IL-1β in the bone loss during rheumatic diseases.

Several inflammatory diseases have been associated with increased bone resorption and fracture rates and different studies supported the relation between inflammatory cytokines and osteoclast activity. The main factor required for osteoclast activation is the stimulation by receptor activator of nuclear factor kappa-B ligand (RANKL) expressed on osteoblasts. In this context, interleukin- (IL-) 1β, one of the most powerful proinflammatory cytokines, is a strong stimulator of in vitro and in vivo bone resorption via upregulation of RANKL that stimulates the osteoclastogenesis. The resulting effects lead to an imbalance in bone metabolism favouring bone resorption and osteoporosis. In this paper, we review the available literature on the role of IL-1β in the pathogenesis of bone loss. Furthermore, we analysed the role of IL-1β in bone resorption during rheumatic diseases and, when available, we reported the efficacy of anti-IL-1β therapy in this field.

Stem cells in autoimmune diseases: Implications for pathogenesis and future trends in therapy

In this review we report the recent progresses, available in the literature, concerning the biology and the potential therapeutic role of both mesenchymal stem cells (MSCs) and hematopoietic stem cells in autoimmune diseases. Mesenchymal stem cells (MSCs) are responsible for the normal turnover and maintenance of adult mesenchymal tissues and their pleiotropic nature allows them to sense and respond to an event in the local environment, be it injury or inflammation. Recently, MSCs have been shown to have immune-modulatory properties and immunosuppressive capacities, acting on different immune cells both in vitro and in vivo, in addition to an immunologically privileged phenotype. Moreover, several works suggest that MSCs are defective in autoimmune diseases. These aspects are now considered the most intriguing aspect of their biology, introducing the possibility that these cells might be used as effective therapy in autoimmune diseases. Autoimmune diseases represent a failure of normal immune regulatory processes as they are characterized by activation and expansion of immune cell subsets in response to non-pathogenic stimuli. As autoimmune diseases can be transferred, or alternatively, cured, by stem cell transplantation, a defect in the hemopoietic stem cell as a cause of autoimmune diseases may be postulated. The rationale for autologous hematopoietic stem cell transplantation (HSCT) in autoimmune diseases is the ablation of an aberrant or self-reactive immune system by chemotherapy and regeneration of a new and hopefully self-tolerant immune system from hematopoietic stem cells. In the past 15years, more than 1500 patients worldwide have received HSCT, mostly autologous, as treatment for a severe autoimmune disease and the majority were affected by multiple sclerosis, systemic sclerosis, systemic lupus erythematosus, rheumatoid arthritis, juvenile idiopathic arthritis and idiopathic cytopenic purpura.

Methotrexate: an old new drug in autoimmune disease.

Methotrexate (MTX) is currently considered, among disease-modifying anti-rheumatic drugs (DMARDs), the ‘anchor-drug’ in the treatment of rheumatoid arthritis. In the last 25 years, there has been a marked expansion in the use of MTX in different inflammatory diseases. Its low cost, associated to a good long-term efficacy and safety profile, justifies the use of MTX as a first-line disease-modifying drug or alternatively, a steroid-sparing medication in this field of medicine. Although new emerging options, including biological treatments, are being established in the therapeutic scenario, the good cost/benefit ratio of MTX supports the choice of this drug in combination with these newer therapies, enhancing the efficacy of these combination therapies and decreasing the risk of potential side effects.

CD4(-)CD8(-) T-cells in primary Sjögren's syndrome: association with the extent of glandular involvement.

OBJECTIVES Growing evidence suggests that IL-17-producing T cells, lacking both CD4 and CD8 molecules and defined as double negative (DN) cells, play a pivotal role in the pathogenesis of a number of systemic autoimmune disorders. We recently demonstrated that this T-cell subset is expanded in the peripheral blood (PB) of patients with primary Sjögrens syndrome (pSS), produces IL-17 and accumulates in minor salivary glands (MSGs). We aimed to investigate glandular and PB DN T cells in early pSS in order to verify a possible correlation with MSGs histological patterns and clinical parameters. METHODS Paired samples of PB mononuclear cells and MSGs from pSS patients were evaluated at the diagnosis by flow cytometry and immunofluorescence staining respectively. Histological analysis to identify histological scores, B/T cell segregation and the presence of germinal center (GC)-like structures was also performed. RESULTS In early stages of pSS, circulating DN T cells appear to be not yet expanded and inversely correlated with circulating CD4(+)Th17 cells. The number of infiltrating DN T cells were associated with extent of glandular involvement, presence of GC-like structures and dryness symptoms and were inversely correlated with circulating DN T cells. CONCLUSIONS Our findings suggest that DN T cells are actively involved in the pathogenic mechanisms leading to glandular dysfunction and damage in pSS and may play a role in ectopic lymphoneogenesis development occurring during the disease.

Methotrexate in Rheumatoid Arthritis: Optimizing Therapy Among Different Formulations. Current and Emerging Paradigms

BACKGROUND Methotrexate (MTX) is currently considered the drug of choice, among the disease-modifying antirheumatic drugs, for the treatment of rheumatoid arthritis (RA) because of its favorable risk/benefit ratio, good safety profile, and low costs. Despite MTXs widespread use and large experience accumulated over the many years since its introduction into clinical practice, specific guidelines have not been published. OBJECTIVE We report here the available research regarding the optimal dosage and route of MTX administration. METHODS MEDLINE and the Cochrane Library were systematically searched for articles published between 1990 and 2013, using terms related to RA and MTX. The search was conducted by using both MeSH terms and free text. The references of the retrieved studies were also screened manually for additional articles. RESULTS For the treatment of rheumatic diseases, the antimetabolite drug MTX can be administered weekly by different routes: oral, subcutaneous, or intramuscular. One of the goals of treatment is to minimize acute and chronic toxicity. A starting dose of 15 mg/week orally, escalating to 25 to 30 mg/week or the highest tolerable dose (with a subsequent switch to parenteral administration in cases of insufficient response), seems to be the optimal evidence-based strategy for MTX treatment of RA. Oral MTX is widely preferred because of its low costs and patient preferences; the bioavailability of parenteral MTX is higher, however. This is supported by data from observational studies, in which patients switching from parenteral to oral MTX at an equal dose had disease exacerbations. In several trials, the subcutaneous formulation of MTX was considered, by both physicians and patients, to be more advantageous in terms of discomfort and compliance. In addition, a significant proportion of patients reported that this formulation led to greater independence, with a resulting improvement in quality of life. CONCLUSIONS Although MTX treatment can be initiated by using the oral administration route, parenteral administration of MTX is indicated in those patients with poor compliance toward the oral form. The subcutaneous route seems to be more effective than the oral route for MTX administration based on the results of several studies, and this route may be preferred because of better usability and absence of pain at the infusion site.

Is minor salivary gland biopsy more than a diagnostic tool in primary Sjo¨gren׳s syndrome? Association between clinical, histopathological, and molecular features: A retrospective study

OBJECTIVES Several histological scoring systems, including the focus score, performed in minor salivary glands (MSGs) by hematoxylin-eosin (H&E) staining, have been employed in clinical practice to assess the inflammatory infiltrate and provide the diagnosis of primary Sjo¨gren׳s syndrome (pSS). Aims of this study were to integrate different scoring systems and identify potential differences in the molecular profile of lymphoid cytokines related to germinal center (GC) formation and clinical subsets in pSS. METHODS Overall, 104 pSS patients and 40 subjects with sicca non-pSS were retrospectively evaluated. MSG biopsies were evaluated by H&E and immunofluorescence to assess histological pattern, Chisholm and Mason grading system, Tarpley score, a grading for the severity of inflammatory infiltrate, T-/B-cell segregation, and the presence of GC. MSGs from 50 pSS patients and 30 sicca non-pSS patients were processed by real-time PCR to assess LTα, LTβ, BAFF, CXCR4, CXCL12, CXCR5, CXCL13, CCR7, CCL19, and CCL21. RESULTS GCs presence was associated with anti-Ro/SSA and anti-La/SSB antibodies, hypergammaglobulinemia, salivary gland swelling, higher Tarpley score and focus score, and extraglandular involvement but, at multivariate analysis, only extraglandular involvement was independently associated to GC. pSS patients displayed higher level of all cytokines compared to those with sicca symptoms. GC(+) pSS patients displayed higher level of all cytokines compared to those GC(-). CONCLUSIONS Our study demonstrates that different histopathological patterns, including GC presence, reflect different cytokine expression and different clinical subsets. We believe that the combined immunofluorescence/molecular approach in MSGs would help to tailor diagnostic and therapeutic approach for different subsets of pSS patients.