Arthritis Rheum
February 2007
Objective: We previously reported that patients with systemic lupus erythematosus (SLE) in the US incurred approximately 19% and 12% higher direct medical costs than patients in Canada and the UK, respectively, without experiencing superior outcomes expressed as disease damage or quality of life. In the present study, we compared cumulative indirect costs over 4 years in these patients.
Methods: A total of 715 patients with SLE (269 US, 231 Canada, 215 UK) were surveyed semiannually for 4 years on employment status and time lost from labor and nonlabor market activities.
Objective: To determine whether there is a link between the frequency of natural killer T (NKT) cells and high levels of IgG in patients with systemic lupus erythematosus (SLE) and their relatives.
Methods: Blood samples were obtained from patients with SLE, their first-degree relatives, patients with rheumatoid arthritis (RA), and healthy control subjects. The frequency of NKT cells (defined as CD56+ T cells) was expressed as a percentage of total blood lymphocytes.
Objective: B lymphocytes from patients with systemic lupus erythematosus (SLE) exhibit defective intracellular signaling, hyperactivity, and autoantibody production. Recent evidence indicates a reduced expression of Lyn kinase, a negative regulator of B cell signaling, and reduced translocation of Lyn into membrane signaling domains in SLE. The present study was undertaken to investigate the causes of this altered regulation of Lyn by assessing the expression levels of regulatory molecules and their translocation into the signaling domains of SLE B lymphocytes.
View Article and Find Full Text PDFObjective: Pathogenic antiphospholipid antibodies (aPL) bind the self antigen N-terminal domain (domain I) of beta(2)-glycoprotein I (beta(2)GPI), with residues G40-R43 being important. However, peptides homologous to other regions of domain I have also been shown to bind aPL. Furthermore, there are no published reports of the effects of altering R39, which has greater surface exposure than the G40-R43 residues.
View Article and Find Full Text PDFPurpose Of Review: Interferons are used to treat a variety of medical conditions. They are integral players in immunity and a number of immune-mediated complications can arise during interferon therapy. We have reviewed the occurrence of these complications, and the mechanisms behind them.
View Article and Find Full Text PDFObjective: Patients with systemic lupus erythematosus (SLE) are significantly more likely to experience a myocardial infarction or a stroke than age-matched controls. We compared the prevalence of conventional and lupus-specific risk factors in patients with SLE just before a cardiovascular event and in matched controls with SLE but no cardiovascular disease (CVD).
Methods: Twenty-nine patients with SLE and CVD were enrolled.
Loss of tolerance to self-Ags in patients with systemic lupus erythematosus (SLE), a prototypic autoimmune disease, is associated with dysregulation of T cell signaling, including the depletion of total levels of lymphocyte-specific protein kinase (Lck) from sphingolipid-cholesterol-enriched membrane microdomains (lipid rafts). Inhibitors of 3-hyroxy-3-methylgluteryl CoA reductase (statins) can modify the composition of lipid rafts, resulting in alteration of T cell signaling. In this study, we show that atorvastatin targets the distribution of signaling molecules in T cells from SLE patients, by disrupting the colocalization of total Lck and CD45 within lipid rafts, leading to a reduction in the active form of Lck.
View Article and Find Full Text PDFObjective: To test the interrater reliability of the revised British Isles Lupus Assessment Group 2004 (BILAG-2004) index for the assessment of systemic lupus erythematosus (SLE) activity.
Methods: Patients with SLE were recruited from 11 centers. Two physician raters separately assessed the patients' disease activity using the BILAG-2004 index in routine clinical practice.
In addition to rheumatoid arthritis (RA), B cells are likely to play a significant role in the development of other autoimmune rheumatic diseases, such as systemic lupus erythematosus (SLE), myositis, and vasculitis. Small-vessel vasculitis subtypes may be immune complex-mediated (cryoglobulinemia) or antineutrophil cytoplasmic antibody (ANCA)-associated; ANCA may be involved in the pathogenesis of vasculitis. In SLE, both antibody-associated and antibody-independent processes are almost certainly involved.
View Article and Find Full Text PDFExpert Rev Clin Immunol
May 2006
Systemic lupus erythematosus (SLE) is a multisystem autoimmune rheumatic disease characterized by the presence of autoantibodies, many of which are directed against antigens of nuclear origin. In the clinical setting, these antibodies are important in the management of patients with SLE, providing information about disease activity, subtype and prognosis. The clearance of apoptotic debris is defective in patients with SLE.
View Article and Find Full Text PDFObjective: A deficiency in a subcomponent of C1q can result in increased susceptibility to autoimmune diseases such as systemic lupus erythematosus (SLE). The monocyte endocytic receptor CD91 is implicated in the endocytosis of apoptotic neutrophils via interactions with C1q and calreticulin. In this clinical study, we studied the binding of C1q to leukocytes and determined whether C1q bound specifically to calreticulin and CD91 on cells undergoing apoptosis in SLE.
View Article and Find Full Text PDFThe aim of this study was to investigate HLA class II associations in polymyositis (PM) and dermatomyositis (DM), and to determine how these associations influence clinical and serological differences. DNA samples were obtained from 225 UK Caucasian idiopathic inflammatory myopathy patients (PM = 117, DM = 108) and compared with 537 randomly selected UK Caucasian controls. All cases had also been assessed for the presence of related malignancy and interstitial lung disease (ILD), and a number of myositis-specific/myositis-associated antibodies (MSAs/MAAs).
View Article and Find Full Text PDFBackground: The antiphospholipid syndrome (APS), characterised by recurrent miscarriage and thrombosis, is a significant cause of morbidity and mortality. Domain I (DI) of human beta 2 glycoprotein I (beta2GPI) is thought to contain crucial antibody binding epitopes for antiphospholipid antibodies (aPL), which are critical to the pathogenesis of APS. Expressing this protein in bacteria could facilitate studies investigating how this molecule interacts with aPL.
View Article and Find Full Text PDFNeonatal lupus erythematosus is a rare disorder caused by the transplacental passage of maternal autoantibodies. The 52-kDa Ro/SSA antigen (Ro52) ribonucleoprotein represents an antigenic target strongly associated with the autoimmune response in mothers whose children have neonatal lupus and cardiac conduction disturbances, mainly congenital heart block. The objective of this study was to identify putative Ro52/60-kDa Ro/SSA antigen (Ro60) epitopes associated with neonatal lupus and congenital heart block.
View Article and Find Full Text PDFObjective: B lymphocytes from patients with systemic lupus erythematosus (SLE) are hyperactive and produce anti-double-stranded DNA (anti-dsDNA) autoantibodies. The cause or causes of B cell defects in SLE are unknown. In this study, we determined the level and subcellular distribution of Lyn protein, a key negative regulator of B cell receptor signaling, and assessed whether altered Lyn expression is characteristic of B cells in the setting of SLE.
View Article and Find Full Text PDFArthritis Res Ther
April 2006
When purified under rigorous conditions, some murine anti-double-stranded-DNA (anti-dsDNA) antibodies actually bind chromatin rather than dsDNA. This suggests that they may actually be antinucleosome antibodies that only appear to bind dsDNA when they are incompletely dissociated from nucleosomes. Experiments in murine models suggest that antibody-nucleosome complexes may play a crucial role in the pathogenesis of glomerulonephritis in systemic lupus erythematosus.
View Article and Find Full Text PDFWhile immunoglobulin G (IgG) antibodies to double-stranded (ds)DNA are serological markers of systemic lupus erythematosus (SLE), not all antibodies to DNA (anti-DNA) are able to cause tissue damage to a similar extent. It has been proposed that anti-DNA-induced renal damage could be linked to differences in the fine specificity of the antibodies. In an attempt to gain insight into their fine binding properties, we investigated the cross-reactivity of two human lupus monoclonal IgG anti-dsDNA (B3 and RH14) to a recently described Escherichia coli PolIV (a DNA polymerase).
View Article and Find Full Text PDFObjective: In a preliminary attempt to develop a drug responder index for patients with systemic lupus erythematosus (SLE), 2 validated disease activity instruments were studied for their responsiveness and compared to a physician visual analog scale (VAS) assessment of disease activity. We attempted to determine whether these validated instruments were useful components in characterizing response in the setting of a clinical trial.
Methods: Eighty paper patients were assessed using the British Isles Lupus Assessment Group (BILAG) and Systemic Lupus Disease Activity Index (SLEDAI) and by physician's assessment of global activity.
We have recently shown that the anti-cardiolipin activity of human anti-phospholipid antibody UK4 (lambda) resides on its heavy chain. We now show that UK4 possesses strong reactivity to the plasma-protein beta2-Glycoprotein I (beta2-GPI) also. Utilizing chain shuffling experiments involving an unrelated anti-p185 antibody 4D5 (kappa) with no reactivity to beta2-GPI, we now demonstrate that both the constructs possessing the auto-antibody-derived light chain exhibited significant binding to beta2-GPI.
View Article and Find Full Text PDFRegulatory T cells have been clearly implicated in the control of disease in murine models of autoimmunity. The paucity of data regarding the role of these lymphocytes in human autoimmune disease has prompted us to examine their function in patients with rheumatoid arthritis (RA). Regulatory (CD4(+)CD25(+)) T cells isolated from patients with active RA displayed an anergic phenotype upon stimulation with anti-CD3 and anti-CD28 antibodies, and suppressed the proliferation of effector T cells in vitro.
View Article and Find Full Text PDFBackground: Splenectomy has been performed to treat refractory autoimmune thrombocytopenia. However, some reports have suggested that an increased risk of thrombosis could be present in splenectomized patients. This study aims to evaluate the possibility of an increased risk of thrombosis after splenectomy in patients with systemic lupus and antiphospholipid syndrome.
View Article and Find Full Text PDFThe fine binding characteristics of three well-characterized human autoantibodies B3, RH14 (anti-DNA) and UK4 (anti-cardiolipin) in their IgG and cloned Fab formats, were investigated. Although in severe combined immunodeficiency (SCID) mice B3 and RH14 both induce proteinuria, only RH14 induces early features of lupus nephritis, whereas UK4 exhibits lupus anticoagulant activity. RH14 exhibited up to 10 fold higher binding to DNA compared to that shown by B3 or UK4 and involved significant electrostatic and phosphate group interactions.
View Article and Find Full Text PDFFeatures of the lymphocyte population in systemic lupus erythematosus (SLE) include a disordered B cell profile and production of autoantibodies. An additional distinctive perturbation is the overexpression of V4-34-encoded serum immunoglobulins (Ig). A similar rise in V4-34-encoded Ig occurs in normal subjects following infection with certain herpesviruses, and is found in Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM).
View Article and Find Full Text PDFSystemic lupus erythematosus (SLE) is characterized by abnormalities in T lymphocyte receptor-mediated signal transduction pathways. Our previous studies have established that lymphocyte-specific protein tyrosine kinase (LCK) is reduced in T lymphocytes from patients with SLE and that this reduction is associated with disease activity and parallels an increase in LCK ubiquitination independent of T cell activation. This study investigated the expression of molecules that regulate LCK homeostasis, such as CD45, C-terminal Src kinase (CSK), and c-Cbl, in lipid raft domains from SLE T cells and investigated the localization of these proteins during T cell receptor (TCR) triggering.
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