Anti-tumor necrosis factor alpha therapy normalizes fibrinolysis impairment in patients with active rheumatoid arthritis.

OBJECTIVES: Rheumatoid arthritis (RA) is associated with increased cardiovascular risk and involvement of inflammation, coagulation and fibrinolysis. Treatment with infliximab, a tumour necrosis factor-alpha (TNF-alpha) blocking chimeric monoclonal antibody, induces a long-term reduction of inflammation and coagulation, but its effect on fibrinolysis is still unknown. We carried out an observational study investigating plasma biomarkers of inflammation and fibrinolysis in RA patients before and after 14 weeks of infliximab treatment given according to the therapeutic guidelines for RA. METHODS: We studied 20 selected patients with active RA and without any other atherosclerosis risk factor as well as 40 healthy controls. Patients, treated with a stable dose of methotrexate, received infliximab (3 mg/kg) at week 0, 2, 6 and 14. At week 0 and 14, we assessed clinical, inflammatory and fibrinolyitic parameters. RESULTS: At baseline, plasminogen activator inhibitor (PAI-1) antigen, PAI-1 activity and tissue-type plasminogen activator (t-PA) antigen were significantly higher in RA patients than in controls (p=0.01, p=0.001 and p=0.0001 respectively). After 14 weeks of infliximab treatment, the levels of PAI-1 antigen, PAI-1 activity and t-PA antigen significantly decreased till normalization (p=0.0001). Plasma levels of C reactive protein (CRP) and interleukin-6 (IL-6) were directly correlated with levels of PAI-1 antigen (p=0.011 and p=0.0001), PAI-1 activity (p=0.013 and p=0.027) and t-PA antigen (p=0.017 and p=0.040). CONCLUSIONS: This study provides evidence that TNF-alpha blockade by infliximab not only decreases inflammation, but also reduces the inhibition of fibrinolysis. Such a combined effect may be pivotal in reducing the whole thrombotic risk in these patients.

Primary antiphospholipid syndrome associated with small aorta syndrome: a case report.

It has been widely accepted that the antiphospholipid syndrome (APS) is an autoimmune hypercoagulability syndrome in which a variety of venous and arterial thrombotic events may occur. Peripheral obliterating arterial disease characterized by aortoiliac steno-occlusion occurring in young women, is reported in the literature under the name of Small Aorta Syndrome (SAS). Although it remains unclear whether SAS represents a separate entity, the small size of the distal aorta increases the risk for aortoiliac occlusive disease. A 41-year old white woman was admitted with acute digital ischemia of the left foot. She had positive lupus anticoagulant and IgG anti-cardiolipin antibodies (61 UI/mL), but antinuclear antibodies and anti-ds-DNA antibodies were negative. She previously had two deep venous thromboses of the legs and, despite the oral anticoagulant therapy, pulmonary embolism occurred. Shortly thereafter, abdominal angio-magnetic resonance imaging suggested that the infra-renal aorta was narrowed more than 50%, without thrombotic occlusion of the terminal aorta and common iliac arteries. These findings were compatible with the features of SAS. There were no atherosclerotic changes in the artery wall and no other prediposing risk factors such as smoking, oral contraceptive or hyperlipidemia. After adequate anticoagulation and intravenous prostacyclin treatment the patient's symptoms and the ischemic lesions improved markedly. To our knowledge this is the first report of the association of SAS and primary APS. The occurrence of SAS in patients with APS may dramatically increase the risk of trombothic events.

[Raynaud's phenomenon]. / Il fenomeno di Raynaud.

Raynaud's phenomenon (RP) is a vasospastic disorder characterized by episodic color changes of blanching, cyanosis, and hyperemia in response to cold and/or emotional stress. Although most typically noted in the fingers, the circulation of the toes, ears, nose and tongue is also frequently affected. Population studies have shown that RP in adults is more common in women than men, with prevalence estimates ranging from 4% to 30%. Geographic variations in the prevalence reflect differences in climate. RP may be a primary or a secondary process. LeRoy and Medsger suggested criteria for primary RP: symmetric attacks, the absence of tissue necrosis, ulceration or gangrene, the absence of a secondary cause, negative antinuclear antibodies, normal nailfold capillaroscopy and a normal erythrocyte sedimentation rate. Secondary RP is characterized by an age of onset of more than 30 years, painful and asymmetric attacks, ischemic skin lesions, positive autoantibodies, capillaroscopic abnormalities and/or clinical features suggestive of connective tissue diseases (CTDs). Among the CTDs, systemic sclerosis has the highest frequency of RP. Finding a cause for RP requires a knowledge of the patient's occupational, smoking, drug history, physical examination, nailfold capillaroscopy, routine laboratory tests and autoantibodies. Furthermore, RP should be distinguished from acrocyanosis, a condition characterized by continuous cyanosis of the hands or feet that is aggravated by cold temperature. The most important instruction to the patient is abstinence from any smoking, offending drugs should be discontinued, and abrupt changes in temperature. If these measures are inadequate, calcium-channel blockers are the most widely used (nifedipine 30 mg up to 90 mg daily). Alternatively, sympatholytic agent (prazosin), angiotensin II -receptor type I antagonist (losartan), selective sertonin-reuptake inhibitor (fluoxetine) may be useful. In the severe cases the role of prostaglandins is well established, but standard therapeutic protocols are not jet available.

[Role of cell migration in the pathogenesis of rheumatoid arthritis: in vivo studies in SCID mice transplanted with human synovial membrane]. / Ruolo della migrazione cellulare nella patogenesi dell'artrite reumatoide: studi in vivo in topi SCID trapiantati con membrana sinoviale umana.

OBJECTIVE: Adhesion mechanisms play a central role in the recruitment of leukocytes which characteristically infiltrate rheumatoid synovium. Therefore, we adapted an animal model, in which human rheumatoid synovium was transplanted into severe combined immunodeficient (SCID) mice, to study the effects of Tumor Necrosis Factor-alpha (TNF-alpha) in modulatine leukocyte migration and to investigate the chemotactic potential of Stromal Derived Factor-1 alpha (SDF-1 alpha). MATERIALS AND METHODS: Human synovium samples, obtained from patients undergoing joint replacement, were divided into two parts. One was analysed by immunohistology and the other was implanted subcutaneously into SCID mice under general anaesthesia. Four weeks post-transplantation, grafts were injected with optimal dose of SDF-1, TNF-alpha or saline (negative control). At the same time, animals were injected iv with fluorescently labelled cells. 48 hours later mice were sacrificed and grafts removed for cryo-hystology. The number of cells migrating to the grafts was determined by UV-microscopy and the results expressed as cells per high power field. RESULTS AND CONCLUSIONS: In these studies we provide the evidence that: 1) the animal model, in which human tissues are grafted into SCID mice, can be used to study cell migration under controlled experimental conditions; 2) direct intragraft injection of TNF-alpha increases lymphocytes migration and up-regulates the expression of human adhesion molecules (CAMs) and 3) SDF-1 alphainjected intragraft increases the migration of the pro-myelo-monocytic U937 cells to synovial transplants, even more efficiently than TNF-alpha, but without modifications of CAMs' expression.

[Role of chemokines in the pathogenesis of chronic synovitis during rheumatoid arthritis]. / Ruolo delle chemochine nella patogenesi della sinovite cronica in corso di artrite reumatoide.

Chemokines play a central role in the pathogenesis of rheumatoid arthritis (RA) synovitis which is characterised by new blood vessel formation, thickening of the lining layer and infiltration of immune cells. The inflammatory infiltrate is generated by a series of events which include the recruitment of leukocytes from the blood stream into the tissue, their local retention and activation to effector cells. All these processes are finely regulated by the interplay of different cell adhesion molecules (CAMs) and chemoattractant factors called chemokines (CK). CK are a superfamily of small proteins that play a crucial role in immune and inflammatory reactions. These chemoattractant cytokines share structural similarities including four conserved cysteine residues which form disulphide bonds in the tertiary structure of the proteins. CK mediate their effects by binding specific receptors (CK-R) characterised by a domain structure which spans the cell membrane seven times and signal through heterotrimeric GPT-binding proteins. Activation of the CK network results in an amplification of the inflammatory cascade and consequently in the progressive destruction of RA joints. The recognition of the central role of CK in inflammation has paved the way to the development of new agents capable of interfering with CK and CK-R. This review will focus in particular on the role of CK in regulating leukocyte trafficking in RA joints.

Stromal cell-derived factor 1 (CXCL12) induces monocyte migration into human synovium transplanted onto SCID Mice.

OBJECTIVE: The mechanisms by which monocyte/macrophage cells migrate to the joint involve a series of integrated adhesion and signaling events in which chemokines and their receptors are strongly implicated. This study was undertaken to investigate the hypothesis that stromal cell-derived factor 1 (SDF-1), a CXC chemokine (CXCL12), plays a critical role in monocyte/macrophage localization to synovium. METHODS: SDF-1 and CXC receptor 4 (CXCR4) expression in rheumatoid arthritis (RA) and osteoarthritis synovium and graft SDF-1, tumor necrosis factor alpha (TNF alpha), and human and murine vascular markers were examined by immunohistochemistry and double-immunofluorescence. The functional capacity of SDF-1 to modulate monocyte migration into joints was investigated by examining the localization of pro-myelomonocytic U937 cells into synovial tissue transplanted into SCID mice. SDF-1, TNF alpha, or saline was injected into graft sites and response determined by the number of fluorescently labeled U937 cells (injected intravenously) detected in grafts by ultraviolet microscopy. RESULTS: SDF-1 and CXCR4 were highly expressed in CD68+ cells in the RA synovium. SDF-1 induced U937 cell migration in vitro and in vivo in a dose-dependent manner and, in vivo, SDF-1 was more effective than TNF alpha. In contrast to TNF alpha, SDF-1 did not induce intracellular adhesion molecule 1 in transplant microvasculature. Furthermore, intragraft injection of SDF-1 did not up-regulate TNF alpha, or vice versa. CONCLUSION: This study demonstrates, for the first time, that SDF-1 is functional in vivo when injected into synovial grafts. In addition, SDF-1 is more potent than TNF alpha, and its mechanisms of action appear to be autonomous. Therefore, SDF-1 may be an important TNF-independent molecule involved in the migration to and retention of inflammatory effector cells in the joint.

[Case report: rheumatoid arthritis and large granular lymphocytes syndrome]. / Artrite reumatoide e leucemia a "large granular lymphocytes": descrizione di un caso clinico.

Felty's syndrome (FS) is a rare complication (less than 1%) of rheumatoid arthritis (RA), with the clinical feature of splenomegaly and neutropenia. Approximately 10-40% of FS patients have an expansion of peripheral blood large granular lymphocytes (LGL). This cell population mainly consists of two subsets: cytotoxic T cells (CD8+, CD57+) and natural killer cells (CD3-,CD8-,CD56+). It has been hypothesised that LGL expansion could be responsible for neutropenia by suppressing neutrophil precursors in the bone marrow, but various mechanisms have been proposed to explain this association. We report a case of a 60-year-old woman with rheumatoid factor positive RA who developed LGL expansion responsible for splenomegaly, but without neutropenia. In conclusion, LGL expansion is an uncommon complication of RA and may be responsible for both FS and clinical pictures resembling FS.