Clinical relevance of nitrated beta 2-glycoprotein I in antiphospholipid syndrome: Implications for thrombosis risk.

Β2-Glycoprotein I (ß2GPI) is an important anti-thrombotic protein and is the major auto-antigen in the antiphospholipid syndrome (APS). The clinical relevance of nitrosative stress in post translational modification of ß2GPI was examined.The effects of nitrated (n)ß2GPI on its anti-thrombotic properties and its plasma levels in primary and secondary APS were determined with appropriate clinical control groups. ß2-glycoprotein I was nitrated at tyrosines 218, 275 and 309. ß2-glycoprotein I binds to lipid peroxidation modified products through Domains IV and V. Nitrated ß2GPI loses this binding (p < 0.05) and had diminished activity in inhibiting platelet adhesion to vWF under high shear flow (p < 0.01). Levels of nß2GPI were increased in patients with primary APS compared to patients with either secondary APS (p < 0.05), autoimmune disease without APS (p < 0.05) or non-autoimmune patients with arterial thrombosis (p < 0.01) and healthy individuals (p < 0.05).In conclusion tyrosine nitration of plasma ß2GPI is demonstrated and has important implications with regards to the pathophysiology of platelet mediated thrombosis in APS. Elevated plasma levels of nß2GPI in primary APS may be a risk factor for thrombosis warranting further investigation.

Evaluation of the ACR and SLICC classification criteria in juvenile-onset systemic lupus erythematosus: a longitudinal analysis.

Objectives The Systemic Lupus International Collaborating Clinics (SLICC) group proposed revised classification criteria for systemic lupus erythematosus (SLICC-2012 criteria). This study aimed to compare these criteria with the well-established American College of Rheumatology classification criteria (ACR-1997 criteria) in a national cohort of juvenile-onset systemic lupus erythematosus (JSLE) patients and evaluate how patients' classification criteria evolved over time. Methods Data from patients in the UK JSLE Cohort Study with a senior clinician diagnosis of probable evolving, or definite JSLE, were analyzed. Patients were assessed using both classification criteria within 1 year of diagnosis and at latest follow up (following a minimum 12-month follow-up period). Results A total of 226 patients were included. The SLICC-2012 was more sensitive than ACR-1997 at diagnosis (92.9% versus 84.1% p < 0.001) and after follow up (100% versus 92.0% p < 0.001). Most patients meeting the SLICC-2012 criteria and not the ACR-1997 met more than one additional criterion on the SLICC-2012. Conclusions The SLICC-2012 was better able to classify patients with JSLE than the ACR-1997 and did so at an earlier stage in their disease course. SLICC-2012 should be considered for classification of JSLE patients in observational studies and clinical trial eligibility.

Notifications for child safeguarding from an acute hospital in response to presentations to healthcare by parents.

BACKGROUND: Consideration of child safeguarding is routine within maternity services but less common in other health services for adults. We audited notifications for child safeguarding from an acute general hospital where the policy includes questioning adults presenting with violence, mental health problems or drug or alcohol misuse to any department within the hospital about children at home and notifying to the local authority children's social care services if there are safeguarding concerns. METHODS: Cross-sectional audit of notifications for child safeguarding, including abuse, neglect or victimization, from all departments in one hospital to the local authority children's social care department during 12 months (2010/11). RESULTS: Of 681 notifications (57 per month), 40% (270/681) were triggered by parents' presentation to acute hospital services. Of these, 37% (100/270; 12 teenage mothers) presented for maternity care and 60% (162/270; 8 teenage parents) presented to the emergency department (ED). Of the 60% (411/681) of notifications prompted by children presenting for healthcare, most originated from the ED (358/411; 87%): two-thirds of these presented with injury (250/358; 70%). CONCLUSION: Given a policy to ask adults about children at home, a substantial proportion of children notified for child safeguarding were recognized through presentations to acute healthcare by their parents. Further research and development of this policy needs to ensure that questioning results in effective interventions for the children and their parents.

In vivo clearance and metabolism of recombinant activated factor VII (rFVIIa) and its complexes with plasma protease inhibitors in the liver.

INTRODUCTION: Recombinant activated factor VII (rFVIIa, NovoSeven®) is injected intravenously for the treatment of haemophilia patients with inhibitory antibodies. In plasma, rFVIIa forms complexes with protease inhibitors, primarily antithrombin III (ATIII). The liver is believed to be involved in clearance of rFVIIa, however, it is not known whether the liver is also involved for the clearance of the rFVIIa-ATIII complex. In this study, we explored the fate of intravenously injected rFVIIa from plasma to the hepatic lysosomes. MATERIALS AND METHODS: A novel method using magnetic chromatography was used to isolate catabolic organelle (CO) fractions from mouse liver following injection of superparamagnetic dextran (SPD)-coated iron oxide particles and rFVIIa. The effect of co-circulating SPD particles on rFVIIa pharmacokinetic (PK) parameters was evaluated by ELISA. Cryo-immuno transmission electron microscopy (TEM) was used to study hepatic distribution of SPD particles and rFVIIa. The isolated hepatic CO fractions were characterized using Western Blotting (WB). RESULTS: Cryo-immuno TEM of the liver confirmed hepatic co-localisation of SPD particles and rFVIIa in identical endosomes and lysosomes of both hepatocytes and Kupffer cells. SPD particles did not affect the PK parameters of rFVIIa. WB analysis of plasma and CO fractions detected rFVIIa as the full-length protein and also in high molecular weight (HMW) complexes with ATIII and α-2 macroglobulin (α-2M). CONCLUSIONS: Following injection, both hepatocytes and Kupffer cells appeared to be involved in the hepatic clearance and metabolism of both full-length rFVIIa and rFVIIa in complex with at least two plasma protease inhibitors; ATIII and α-2M.

Redox control of ß2-glycoprotein I-von Willebrand factor interaction by thioredoxin-1.

BACKGROUND: ß(2) -Glycoprotein I (ß(2) GPI) is an abundant plasma protein that is closely linked to blood clotting, as it interacts with various protein and cellular components of the coagulation system. However, the role of ß(2) GPI in thrombus formation is unknown. We have recently shown that ß(2) GPI is susceptible to reduction by the thiol oxidoreductases thioredoxin-1 and protein disulfide isomerase, and that reduction of ß(2) GPI can take place on the platelet surface. METHODS: ß(2) GPI, reduced by thioredoxin-1, was labeled with the selective sulfhydryl probe N(a)-(3-maleimidylpropionyl)biocytin and subjected to mass spectrometry to identify the specific cysteines involved in the thiol exchange reaction. Binding assays were used to examine the affinity of reduced ß(2) GPI for von Willebrand factor (VWF) and the effect of reduced ß2GPI on glycoprotein (GP)Ibα binding to VWF. Platelet adhesion to ristocetin-activated VWF was studied in the presence of reduced ß(2) GPI. RESULTS: We demonstrate that the Cys288-Cys326 disulfide in domain V of ß(2) GPI is the predominant disulfide reduced by thioredoxin-1. Reduced ß(2) GPI in vitro displays increased binding to VWF that is dependent on disulfide bond formation. ß(2) GPI reduced by thioredoxin-1, in comparison with non-reduced ß(2) GPI, leads to increased binding of GPIbα to VWF and increased platelet adhesion to activated VWF. CONCLUSIONS: Given the importance of thiol oxidoreductases in thrombus formation, we provide preliminary evidence that the thiol-dependent interaction of ß(2) GPI with VWF may contribute to the redox regulation of platelet adhesion.

Domain I of beta2-glycoprotein I: its role as an epitope and the potential to be developed as a specific target for the treatment of the antiphospholipid syndrome.

Antiphospholipid syndrome (APS) represents one of the most common acquired causes of thrombophilia and recurrent miscarriages. The only treatment of proven benefit is anticoagulation, often required at high intensity and life-long duration. This therapy can be associated with side effects such as bleeding and is not always effective. Hence, there remains a need for safer, targeted and ideally more effective therapies. Antiphospholipid antibodies (aPL) are pathogenic and promote thrombosis. Independent groups, including our own, have show that the major epitopes that pathogenic aPL targets lie within domain I of the protein beta2-glycoprotein I (beta2GPI). This review focuses on the evidence presented thus far which characterizes the immunodominant epitopes within domain I, demonstrating that the epitope is a conformational one centred around residues R39-G43 and also involving other residues within domain I, such as residues D8 and D9. The hypothesis is proposed that a recombinant domain I molecule, and a recombinant mutant domain I with enhanced aPL binding properties, may be used as an inhibitor of aPL binding and thus inhibit aPL-induced pathogenicity. In vivo proof-of-concept studies within the murine femoral vein injury model are presented supporting this hypothesis, and the rationale as well as potential benefits and problems of employing such an approach to treat APS are discussed.

In vivo inhibition of antiphospholipid antibody-induced pathogenicity utilizing the antigenic target peptide domain I of beta2-glycoprotein I: proof of concept.

SUMMARY OBJECTIVES: In the antiphospholipid syndrome (APS), the immunodominant epitope for the majority of circulating pathogenic antiphospholipid antibodies (aPLs) is the N-terminal domain I (DI) of beta(2)-glycoprotein I. We have previously shown that recombinant DI inhibits the binding of aPLs in fluid phase to immobilized native antigen, and that this inhibition is greater with the DI(D8S/D9G) mutant and absent with the DI(R39S) mutant. Hence, we hypothesized that DI and DI(D8S/D9G) would inhibit aPL-induced pathogenicity in vivo. METHODS: C57BL/6 mice (n = 5, each group) were injected with purified IgG derived from APS patients (IgG-APS, 500 microg) or IgG from normal healthy serum (IgG-NHS) and either recombinant DI, DI(R39S), DI(D8S/D9G), or an irrelevant control peptide (at 10-40 microg). Outcome variables measured were femoral vein thrombus dynamics in treated and control groups following standardized vessel injury, expression of vascular cell adhesion molecule-1 (VCAM-1) on the aortic endothelial surface, and tissue factor (TF) activity in murine macrophages. RESULTS: IgG-APS significantly increased thrombus size as compared with IgG-NHS. The IgG-APS thrombus enhancement effect was abolished in mice pretreated with recombinant DI (P

Juvenile dermatomyositis with Sjögren's syndrome.

Juvenile dermatomyositis (JDM) is a rare disease, and Sjögren's syndrome (SS) is unusual in adolescents. We report the first case of biopsy-proven JDM and SS with pulmonary involvement. A 15-year-old adolescent boy presented with recurrent parotid gland hypertrophy, severe muscle weakness, pronounced skin rash and widespread lymphadenopathy. JDM was diagnosed by clinical examination, elevated muscle enzymes, electromyography and muscle biopsy; SS was diagnosed by xerostomia, anti-Ro (SS-A) positivity and histopathological analysis of salivary gland tissue. This case illustrates a systematic approach which we feel is especially important in the younger patient with a more plastic immune system.

B cell depletion therapy for patients with systemic lupus erythematosus results in a significant drop in anticardiolipin antibody titres.

BACKGROUND: B cell depletion therapy (BCDT) has recently been used with success to treat patients with rheumatoid arthritis and systemic lupus erythematosus (SLE). As antiphospholipid antibodies have been implicated in the pathogenesis of the antiphospholipid syndrome (APS), we asked the question whether BCDT affects levels of IgG anticardiolipin antibodies (aCL) in our cohort of 32 SLE patients given this treatment. METHODS: We identified seven SLE patients who had undergone BCDT and had had at least two moderate positive aCL titres at least 12 weeks apart. Of these only one patient had APS. IgG aCL were measured at time 0 and 6-9 months post BCDT. RESULTS: At time 0, the mean IgG aCL level was 20.6 standardized IgG antiphospholipid units (GPLU) (range (SD) 10-32, (10.1), normal level <5). At 6-9 months post depletion the IgG aCL levels in six of the seven patients was undetectable and in the other patient the level reduced from 25 GPLU to 15 GPLU (p<0.005, two-tailed paired t test). At baseline, only one patient had a mildly positive anti-beta(2)-glycoprotein I (beta(2)GPI) antibody level at 30% (compared to an in-house standard), which fell to 5% post-BCDT. CONCLUSIONS: This small observational study in patients with SLE is the first to demonstrate that BCDT results in a significant reduction in levels of IgG aCL.

Circulating serotypes and antimicrobial sensitivity of Streptococcus pyogenes isolates from children in Cyprus.

The most common T-serotypes among group A streptococci (n = 88) isolated from pharyngeal samples of children referred to a tertiary hospital in Cyprus for pharyngitis or scarlet fever during a 14-month period (2003-2004) were T28 (25%), T8/25/Imp19 (22.7%) and T12 (9.1%). All 88 isolates were sensitive to penicillin and clindamycin, but 1.1% and 18.2% of isolates were resistant to erythromycin and tetracycline, respectively. Macrolide consumption was estimated at 1.7 defined daily doses/1000 inhabitants/day. The low percentage of resistance to macrolides may have been related, at least in part, to the low consumption of macrolides.

Review of presentations at the 6th European Lupus Meeting 3-5 March 2005.

The 6th European Lupus Meeting was held at the Royal College of Physicians of London and was attended by 450 delegates. The conference brought together leading speakers from Europe and North America who reviewed current knowledge and exciting new developments in both clinical and basic science aspects of systemic lupus erythematosus. This review summarizes the major points covered in each session.

The NPC1 protein: structure implies function.

Niemann-Pick type C (NPC) is a lysosomal storage disorder, characterized by intracellular accumulation of low-density lipoprotein (LDL)-derived cholesterol and neurodegeneration leading to premature death. The most common form of the disease, NPC1, results from mutations in the NPC1 gene. Thus, the NPC1 protein is the focus of intense investigation to elucidate the function of this protein and its role in the disease pathogenesis. Recent studies have revealed the NPC1 subcellular location, topology and potential functions of the NPC1 protein. In lieu of direct experimental evidence, certain hypotheses about the function of NPC1 can be inferred by analyzing disease-causing mutations, NPC1 protein sequence homology to other related proteins, and the potential tertiary structure similarity between NPC1 and its prokaryotic ancestors, such as the E. coli RND permease AcrB. This review will discuss recent work on the characterization and function of the NPC1 protein and highlight structural features that may be important in assisting in the elucidation of NPC1 function and role in subcellular lipid transport and homeostasis.

Therapeutic benefit of blocking interleukin-6 activity with an anti-interleukin-6 receptor monoclonal antibody in rheumatoid arthritis: a randomized, double-blind, placebo-controlled, dose-escalation trial.

OBJECTIVE: To investigate the safety and efficacy of MRA, a recombinant human anti-interleukin-6 (anti-IL-6) receptor monoclonal antibody of the IgG1 subclass that inhibits the function of IL-6, in patients with established rheumatoid arthritis (RA). METHODS: A randomized, double-blind, placebo-controlled, dose-escalation trial was conducted in 45 patients with active RA, as defined by the American College of Rheumatology (ACR) revised criteria. Patients were sequentially allocated to receive a single intravenous dose of either 0.1, 1, 5, or 10 mg/kg of MRA or placebo. The primary efficacy end point was meeting the ACR 20% response criteria at week 2 after treatment. RESULTS: Demographic features were similar between treatment groups. At week 2, a significant treatment difference was observed between the 5 mg/kg of MRA and placebo, with 5 patients (55.6%) in the MRA cohort and none in the placebo cohort achieving ACR 20% improvement. There was no statistically significant difference in the ACR 20% response between the other 3 MRA cohorts and placebo at week 2. The mean disease activity score at week 2 in those who received 5 mg/kg and 10 mg/kg of MRA was 4.8 and 4.7 (P < 0.001 and P < 0.001 by analysis of variance), respectively. These mean scores were statistically significantly lower than those in the 0.1- and 1-mg/kg MRA and the placebo cohorts (6.4, 6.2, and 7.0, respectively). The erythrocyte sedimentation rate and C-reactive protein values fell significantly in the 5- and 10-mg/kg MRA cohorts and normalized 2 weeks after treatment. Seventeen patients (5, 4, 6, 2, and 0 patients in the placebo, 0.1-, 1-, 5-, and 10-mg/kg MRA cohorts, respectively) required corticosteroid or disease-modifying antirheumatic drug treatment because of active disease before study end. They were regarded as nonresponders from the time they received these treatments. Diarrhea was the most common adverse event, occurring in 8% of patients. Seven patients (15.6%) reported a severe adverse event (3, 1, 2, and 2 patients in the placebo, 0.1-, 1-, and 10-mg/kg MRA cohorts). There were no serious adverse events that were thought to be related to the study drug. CONCLUSION: This is the first randomized controlled trial showing that inhibition of IL-6 significantly improved the signs and symptoms of RA and normalized the acute-phase reactants. Further research with multiple dosing is necessary to define the most appropriate therapeutic regimen of MRA in RA.

Current concepts for the management of systemic lupus erythematosus in adults: a therapeutic challenge.

Systemic lupus erythematosus (SLE) is a chronic, autoimmune rheumatic disease with many clinical presentations typically affecting women of childbearing age. The successful therapy of SLE depends upon treating both symptoms and the underlying inflammation. Both non-pharmacological as well as pharmacological therapies are invariably required. Non-pharmacological therapy includes avoiding over-exposure to sunlight with the use of adequate sunscreen protection, avoiding "live" vaccination if on immunosuppressive agents, adherence to a diet low in saturated fat and high in fish oil, stress avoidance, and smoking cessation. Pharmacological measures revolve around four main classes of drugs: non-steroidal anti-inflammatory drugs, antimalarials, corticosteroids, and cytotoxic agents. Cyclophosphamide and azathioprine are the two most commonly used cytotoxic agents and these in combination with corticosteroids need to be employed early if there is major organ involvement to prevent or minimise irreversible damage. The potential side effects of corticosteroids and cytotoxic agents need constant consideration. The rapid developments in biotechnology of recent years may soon lead to new and more specific therapies for patients with SLE.

Outcome of a cohort of 300 patients with systemic lupus erythematosus attending a dedicated clinic for over two decades.

OBJECTIVE: To examine the mortality rate and causes of death in a cohort of 300 patients with systemic lupus erythematosus (SLE). METHODS: A retrospective analysis was performed on all patients attending the SLE clinic between 1978 and 2000. Information was obtained on those patients lost to follow up. Cause of death was analysed and categorised as early (<5 years after diagnosis of SLE) and late (>5 years after diagnosis of SLE). Standardised mortality rates were obtained. RESULTS: The patients were followed up for a median of 8.3 years. Seventy three (24%) patients were no longer followed up at the end of the study period, of whom 41 (14%) had died. Of the 32 patients lost to follow up, 14 were being actively followed up within the UK, 16 were followed up outside the UK, and two patients were untraceable. The most common cause of death was malignancy, which accounted for eight (20%) deaths, followed by infection and vascular disease, which accounted for seven (17%) deaths each. CONCLUSIONS: Malignancy was the most common cause of death. Cause of death varied depending on disease duration. Forty per cent of early deaths were due to SLE related renal disease, whereas 23% of late deaths were due to vascular causes. Death due to infection occurred throughout the follow up period. There was a fourfold increased risk of death in our cohort of patients with SLE compared with the general population.

Outcome in patients with idiopathic inflammatory myositis: morbidity and mortality.

OBJECTIVE: To assess the long-term outcome of a cohort of 46 patients with idiopathic myositis by assessing both health status, as measured by the SF-36, and cumulative survival probability over a 20-yr follow-up period at a single rheumatology centre. Methods and results. Forty-six patients under long-term follow-up from 1978 to 1999 were identified from our database. All patients fulfilled three out of four of the Bohan and Peter criteria for myositis. We excluded those with malignancy-associated disease and those with inclusion body myositis. Twenty-three patients (50%) had adult-onset polymyositis, 14 (30.4%) had adult-onset dermatomyositis, one had childhood-onset dermatomyositis and eight (17.4%) had an overlap syndrome (associated with either systemic lupus erythematosus or rheumatoid arthritis). During the course of the disease, seven patients (15.2%) went into full remission, eight (17.4%) had monophasic illness, nine (19.6%) had a relapsing-remitting course, 16 (34.8%) had chronic progressive illness and six (13.04%) died. All patients had significantly lower SF-36 scores in all aspects of health compared with the general population (P< or =0.001). Patients with chronic progressive illness had significantly greater bodily pain (P< or =0.05, t-test) than those with a relapsing-remitting illness, but did not differ in other aspects of health. There was no significant difference in the scores in the different domains of the SF-36 between the patients with active disease and those with inactive disease (0.05

Apoptosis-induced release of mature sterol regulatory element-binding proteins activates sterol-responsive genes.

It is well established that during the execution of the apoptotic cascade, activated caspase 3 releases sterol regulatory element-binding proteins (SREBP) from the membrane of the endoplasmic reticulum in a proteolytic reaction that is distinct from their normal sterol-dependent activation. However, it is not known whether these transcription factors are capable of activating sterol-responsive genes under such conditions. The construction of SRE expression vectors has permitted characterization of the apoptotic activation of SREBP. Cell lines stably expressing the plasma membrane marker CD32, or GFP, under the control of the SRE promoter were shown to modulate SRE gene expression on the basis of the levels of available sterols. However, during the induction of apoptosis, expression of CD32 and GFP was highly induced, even in the presence of ample sterols. Apoptotic induction of sterol-regulated genes was due to activation of caspase 3 and was impervious to treatment with sphingomyelinase, indicating that activation of SRE genes during apoptosis is sterol independent. Further characterization of this apoptotic response indicated that sterol-regulated genes are activated at an early stage in the apoptotic cascade, preceding the externalization of phosphatidylserine on the plasma membrane of apoptotic cells. These results suggest that activation of sterol-responsive genes early during apoptosis may play a role in the proper execution of this program.

Accumulation of cholera toxin and GM1 ganglioside in the early endosome of Niemann-Pick C1-deficient cells.

We investigated intracellular trafficking of GM1 ganglioside in Niemann-Pick C1 (NPC1)-deficient Chinese hamster ovary cells [NPC1(-) cells] by using cholera toxin (CT) as a probe. Both the holotoxin and the B subunit (CTB) accumulated in GM1-enriched intracellular vesicles of NPC1(-) cells. CTB-labeled vesicles contained the early endosome marker Rab5 but not lysosome-associated membrane protein 2 and were not labeled with either Texas red-transferrin or Lysotracker, indicating that they represent early endosomes. Similarly, CT accumulated in intracellular vesicles of human NPC fibroblasts that contained both Rab5 and early endosomal antigen 1. CTB accumulation in NPC1(-) cells was abolished by expression of wild-type NPC1 but not by mutant proteins with a mutation either in the NPC domain or the sterol-sensing domain. A part of these mutant NPC1 proteins expressed in NPC1(-) cells was localized on CTB-labeled vesicles. U18666A treatment of "knock in" cells [NPC1(-) cells that stably expressed wild-type NPC1] caused CTB accumulation similar to that in NPC1(-) cells, and a part of wild-type NPC1was localized on CTB-labeled vesicles in drug-treated cells. Finally, CT tracer experiments in NPC1(-) cells revealed retarded excretion of internalized toxin into the culture medium and an increase in the intracellular release of A subunits. In accordance with the latter result, CT was more effective in stimulating cAMP formation in NPC1(-) than in wild-type cells. These results suggest that transport of CT/GM1 complexes from the early endosome to the plasma membrane depends on the function of NPC1, whereas transport to the Golgi apparatus/endoplasmic reticulum does not.