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ID PMID Title PublicationDate abstract
22438271 Adeno-associated virus-delivered polycistronic microRNA-clusters for knockdown of vascular 2012 May BACKGROUND: Vascular endothelial growth factor (VEGF) is an angiogenic growth factor that plays a critical role in several diseases, including cancer, rheumatoid arthritis and diseases of the eye. Persistent regulation of VEGF by expression of small interfering RNAs targeting VEGF represents a potential future strategy for treatment of such diseases. As a step toward this goal, the present study combines the potency of VEGF-targeted miRNA mimics, produced from a miRNA cluster, with delivery by adeno-associated virus (AAV)-based vectors. METHODS: Nine different engineered tri-cistronic miRNA clusters encoding anti-VEGF effectors were generated and tested in adult human retinal pigment epithelial (ARPE-19) cells using Renilla luciferase screening, quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), western blotting and immunostaining analysis. In vivo efficacy was tested by the injection of scAAV2/8 vectors expressing the most effective miRNA cluster into murine hindlimb muscles, followed by quantitative RT-PCR. RESULTS: Plasmids containing anti-VEGF miRNA clusters showed efficient silencing of VEGF and demonstrated a combined gene silencing effect for miRNA clusters composed of multiple miRNA-mimicked RNA interference effectors. The most potent molecule, miR-5,10,7, resulted in a knockdown of VEGF by approximately 75%. Injection of scAAV2/8 vectors expressing miR-5,10,7 into murine hindlimb muscles, resulted in a 44% reduction of endogenous VEGF. CONCLUSIONS: We have developed miRNA clusters encoding anti-VEGF effectors and shown, in a mouse model, that VEGF is efficiently down-regulated by scAAV2/8-delivered miRNA clusters, allowing potent attenuation of VEGF. These findings may contribute to the development of gene therapy based on AAV-mediated delivery of miRNA clusters.
22347509 Caffeic acid phenethyl ester and its amide analogue are potent inhibitors of leukotriene b 2012 BACKGROUND: 5-lipoxygenase (5-LO) catalyses the transformation of arachidonic acid (AA) into leukotrienes (LTs), which are important lipid mediators of inflammation. LTs have been directly implicated in inflammatory diseases like asthma, atherosclerosis and rheumatoid arthritis; therefore inhibition of LT biosynthesis is a strategy for the treatment of these chronic diseases. METHODOLOGY/PRINCIPAL FINDINGS: Analogues of caffeic acid, including the naturally-occurring caffeic acid phenethyl ester (CAPE), were synthesized and evaluated for their capacity to inhibit 5-LO and LTs biosynthesis in human polymorphonuclear leukocytes (PMNL) and whole blood. Anti-free radical and anti-oxidant activities of the compounds were also measured. Caffeic acid did not inhibit 5-LO activity or LT biosynthesis at concentrations up to 10 µM. CAPE inhibited 5-LO activity (IC(50) 0.13 µM, 95% CI 0.08-0.23 µM) more effectively than the clinically-approved 5-LO inhibitor zileuton (IC(50) 3.5 µM, 95% CI 2.3-5.4 µM). CAPE was also more effective than zileuton for the inhibition of LT biosynthesis in PMNL but the compounds were equipotent in whole blood. The activity of the amide analogue of CAPE was similar to that of zileuton. Inhibition of LT biosynthesis by CAPE was the result of the inhibition of 5-LO and of AA release. Caffeic acid, CAPE and its amide analog were free radical scavengers and antioxidants with IC(50) values in the low µM range; however, the phenethyl moiety of CAPE was required for effective inhibition of 5-LO and LT biosynthesis. CONCLUSIONS: CAPE is a potent LT biosynthesis inhibitor that blocks 5-LO activity and AA release. The CAPE structure can be used as a framework for the rational design of stable and potent inhibitors of LT biosynthesis.
22307629 IL-33 is processed into mature bioactive forms by neutrophil elastase and cathepsin G. 2012 Jan 31 Interleukin-33 (IL-33) (NF-HEV) is a chromatin-associated nuclear cytokine from the IL-1 family, which has been linked to important diseases, including asthma, rheumatoid arthritis, ulcerative colitis, and cardiovascular diseases. IL-33 signals through the ST2 receptor and drives cytokine production in type 2 innate lymphoid cells (ILCs) (natural helper cells, nuocytes), T-helper (Th)2 lymphocytes, mast cells, basophils, eosinophils, invariant natural killer T (iNKT), and natural killer (NK) cells. We and others recently reported that, unlike IL-1β and IL-18, full-length IL-33 is biologically active independently of caspase-1 cleavage and that processing by caspases results in IL-33 inactivation. We suggested that IL-33, which is released upon cellular damage, may function as an endogenous danger signal or alarmin, similar to IL-1α or high-mobility group box 1 protein (HMGB1). Here, we investigated the possibility that IL-33 activity may be regulated by proteases released during inflammation. Using a combination of in vitro and in vivo approaches, we demonstrate that neutrophil serine proteases cathepsin G and elastase can cleave full-length human IL-33(1-270) and generate mature forms IL-33(95-270), IL-33(99-270), and IL-33(109-270). These forms are produced by activated human neutrophils ex vivo, are biologically active in vivo, and have a ~10-fold higher activity than full-length IL-33 in cellular assays. Murine IL-33 is also cleaved by neutrophil cathepsin G and elastase, and both full-length and cleaved endogenous IL-33 could be detected in the bronchoalveolar lavage fluid in an in vivo model of acute lung injury associated with neutrophil infiltration. We propose that the inflammatory microenvironment may exacerbate disease-associated functions of IL-33 through the generation of highly active mature forms.
22134438 Arthrodesis of the first metatarsal-phalangeal joint with flexible, ridged titanium intram 2012 Feb Myriad forms of fixation have been proposed for arthrodesis of the first metatarsal-phalangeal joint (MTPJ). However, nonunion of the arthrodesis site remains a common complication. The authors performed a retrospective review of all patients undergoing arthrodesis of the first MTPJ with flexible titanium intramedullary nails alone or supplemented with static staples followed by immediate protected weight bearing. Subjects were included if they had surgery performed only by one of us; not undergone bilateral surgery in the same setting; surgery for pathology of the first MTPJ other than rheumatoid arthritis; weight-bearing preoperative radiographs; postoperative weight-bearing radiographs demonstrating presence or absence of union at the arthrodesis site; initiated weight bearing on the operative foot immediately postoperative in a protective shoe; and documentation of any complications. A total of 128 patients (148 feet) met inclusion criteria and were included. There were 110 (85.9%) females and 18 (14.1%) males with a mean age ± SD of 64 ± 14.1 years. Indications included (a) 93 (62.8%) severe hallux valgus deformity, (b) 37 (25%) hallux rigidus, and (c) 18 (12.2%) failed first MTPJ surgeries. Ten different configurations where included based on the requirements needed to achieve a solid construct intraoperatively. There were a total of 9 (6.1%) complications consisting of 4 (2.7%) asymptomatic nonunions, 4 (2.7%) hardware removals, and 1 (0.7%) loss of reduction requiring revision surgery. The incidence of nonunion with flexible titanium intramedullary nails alone or supplemented with static staples followed by immediate protected weight bearing for predominantly severe hallux valgus and hallux rigidus is lower than the historic mean for most other fixation techniques. However, there is still a need for methodologically sound prospective cohort studies that focus on the use of isolated arthrodesis of the first MTPJ for purely severe hallux valgus or hallux rigidus, and comparison of the technique presented here with other modern osteosynthesis techniques. Levels of Evidence : Therapeutic, Level IV.
22053109 Historical perspectives on tumor necrosis factor and its superfamily: 25 years later, a go 2012 Jan 19 Although activity that induced tumor regression was observed and termed tumor necrosis factor (TNF) as early as the 1960s, the true identity of TNF was not clear until 1984, when Aggarwal and coworkers reported, for the first time, the isolation of 2 cytotoxic factors: one, derived from macrophages (molecular mass 17 kDa), was named TNF, and the second, derived from lymphocytes (20 kDa), was named lymphotoxin. Because the 2 cytotoxic factors exhibited 50% amino acid sequence homology and bound to the same receptor, they came to be called TNF-α and TNF-β. Identification of the protein sequences led to cloning of their cDNA. Based on sequence homology to TNF-α, now a total of 19 members of the TNF superfamily have been identified, along with 29 interacting receptors, and several molecules that interact with the cytoplasmic domain of these receptors. The roles of the TNF superfamily in inflammation, apoptosis, proliferation, invasion, angiogenesis, metastasis, and morphogenesis have been documented. Their roles in immunologic, cardiovascular, neurologic, pulmonary, and metabolic diseases are becoming apparent. TNF superfamily members are active targets for drug development, as indicated by the recent approval and expanding market of TNF blockers used to treat rheumatoid arthritis, psoriasis, Crohns disease, and osteoporosis, with a total market of more than US $20 billion. As we learn more about this family, more therapeutics will probably emerge. In this review, we summarize the initial discovery of TNF-α, and the insights gained regarding the roles of this molecule and its related family members in normal physiology and disease.
21931678 Sirtinol treatment reduces inflammation in human dermal microvascular endothelial cells. 2011 Histone deacetylases (HDAC) are key enzymes in the epigenetic control of gene expression. Recently, inhibitors of class I and class II HDAC have been successfully employed for the treatment of different inflammatory diseases such as rheumatoid arthritis, colitis, airway inflammation and asthma. So far, little is known so far about a similar therapeutic effect of inhibitors specifically directed against sirtuins, the class III HDAC. In this study, we investigated the expression and localization of endogenous sirtuins in primary human dermal microvascular endothelial cells (HDMEC), a cell type playing a key role in the development and maintenance of skin inflammation. We then examined the biological activity of sirtinol, a specific sirtuin inhibitor, in HDMEC response to pro-inflammatory cytokines. We found that, even though sirtinol treatment alone affected only long-term cell proliferation, it diminishes HDMEC inflammatory responses to tumor necrosis factor (TNF)α and interleukin (IL)-1β. In fact, sirtinol significantly reduced membrane expression of adhesion molecules in TNFã- or IL-1β-stimulated cells, as well as the amount of CXCL10 and CCL2 released by HDMEC following TNFα treatment. Notably, sirtinol drastically decreased monocyte adhesion on activated HDMEC. Using selective inhibitors for Sirt1 and Sirt2, we showed a predominant involvement of Sirt1 inhibition in the modulation of adhesion molecule expression and monocyte adhesion on activated HDMEC. Finally, we demonstrated the in vivo expression of Sirt1 in the dermal vessels of normal and psoriatic skin. Altogether, these findings indicated that sirtuins may represent a promising therapeutic target for the treatment of inflammatory skin diseases characterized by a prominent microvessel involvement.
21912082 Clinical features and outcome of acute exacerbation of interstitial pneumonia: collagen va 2012 BACKGROUND: Relatively little is known about acute exacerbation (AE) of interstitial pneumonia associated with collagen vascular diseases (CVD-IPs). OBJECTIVES: This study was aimed at clarifying clinical characteristics and outcome in AE of CVD-IPs, compared with those of idiopathic interstitial pneumonias (IIPs). METHODS: We retrospectively reviewed 112 admission cases with suspected AE of CVD-IPs or IIPs during 2003-2009. IIPs were diagnosed with idiopathic pulmonary fibrosis (IPF) or non-IPF, mostly based on radiologic findings. Of these, 15 AEs of CVD-IPs (6 rheumatoid arthritis, 6 dermatomyositis and 3 systemic sclerosis) and 47 AEs of IIPs (13 IPF and 34 non-IPF) were included. RESULTS: The clinical characteristics in AE of CVD-IPs were similar to those of IIPs, except for younger age (63.3 ± 6.8 vs. 73.8 ± 9.1 years; p = 0.0001) and higher PaO(2)/FiO(2) at the onset of AE (205 ± 81.2 vs. 145 ± 53.8 mm Hg; p = 0.002) in the former. Dermatomyositis-related interstitial pneumonia (IP) showed a relatively indolent onset and was often associated with worsening control of the underlying disease, whereas AE of other CVD-IPs resembled that of IIPs. 90-day mortality of 33% in AE of CVD-IPs was similar to that of IIPs (44%; p = 0.44) or non-IPF (34%; p = 0.94), but was significantly better than that of IPF (69%; p = 0.04). CONCLUSION: Clinical features and outcome in AE of CVD-IPs were similar, if not identical, to those of IIPs, having a significant impact on the clinical course. AE of advanced IPF with typical radiologic features seems to have higher mortality compared with other forms of IP.
21892841 JAKs go nuclear: emerging role of nuclear JAK1 and JAK2 in gene expression and cell growth 2011 Dec The four Janus kinases (JAKs) comprise a family of intracellular, nonreceptor tyrosine kinases that first gained attention as signaling mediators of the type I and type II cytokine receptors. Subsequently, the JAKs were found to be involved in signaling downstream of the insulin receptor, a number of receptor tyrosine kinases, and certain G-protein coupled receptors. Although a number of cytoplasmic targets for the JAKs have been identified, their predominant action was found to be the phosphorylation and activation of the signal transducers and activators of transcription (STAT) factors. Through the STATs, the JAKs activate gene expression linked to cellular stress, proliferation, and differentiation. The JAKs are especially important in hematopoiesis, inflammation, and immunity, and aberrant JAK activity has been implicated in a number of disorders including rheumatoid arthritis, psoriasis, polycythemia vera, and myeloproliferative diseases. Although once thought to reside strictly in the cytoplasm, recent evidence shows that JAK1 and JAK2 are present in the nucleus of certain cells often under conditions associated with high rates of cell growth. Nuclear JAKs have now been shown to affect gene expression by activating other transcription factors besides the STATs and exerting epigenetic actions, for example, by phosphorylating histone H3. The latter action derepresses global gene expression and has been implicated in leukemogenesis. Nuclear JAKs may have a role as well in stem cell biology. Here we describe recent developments in understanding the noncanonical nuclear actions of JAK1 and JAK2.
21875375 Study of polymorphisms in 4q27, 10p15, and 22q13 regions in autoantibodies stratified type 2011 Dec Type 1 diabetes (T1D) is a multifactorial disease mainly associated with the human leukocyte antigen region. Previous studies suggested the association of interleukin-2 (IL2) gene polymorphisms and its alpha- and beta-chain receptor (IL2RA and IL2RB) variants with different autoimmune diseases such as T1D, celiac disease, multiple sclerosis, and rheumatoid arthritis. All T1D studies were conducted in diabetic patients younger than 17 years at diagnosis. The aim of our study was to replicate these associations not only in pediatric patients, but also in individuals with late onset. We performed a genetic association study of chromosomal regions 4q27, 10p15, and 22q13 containing the IL2, IL2RA, and IL2RB genes in 445 T1D subjects and 828 healthy controls. Seven single nucleotide polymorphisms (SNPs) were selected, previously described as genetic factors related to several autoimmune diseases, and were analyzed by TaqMan assays. The reported association with T1D patients of the IL2RA-rs41295061 located in the 10p15 region was replicated and our data suggest a trend of association of the polymorphisms IL2-rs17388568 and IL2-rs6822844 in 4q27. The effect of these markers was independent of the age at disease onset. Furthermore, the polymorphisms studied in 4q27 were not dependent on the presence of autoantibodies; however, the effect of the associated SNP in 10p15 (IL2RA-rs41295061) was specific of patients sera positive for diabetes antibodies. In conclusion, our results seem to indicate that late-onset and young T1D patients share most genetic factors located in the studied regions, but some markers could correlate with the presence of T1D specific autoantibodies.
21357535 Stat6 and c-Jun mediate Th2 cell-specific IL-24 gene expression. 2011 Apr 1 TCR signaling regulates multiple aspects of T cell function by controlling expression of various cytokine genes. IL-24 is a multifunctional cytokine belonging to the IL-10 family. It displays anticancer effects in diverse cancer cells and regulates immunopathology of psoriasis and rheumatoid arthritis. IL-24 also plays an important role in B cell differentiation. Mouse IL-24 gene is selectively expressed in activated Th2 cells upon TCR stimulation. However, the molecular mechanisms by which TCR stimulation induces IL-24 gene expression are still unclear. In this study, to elucidate the mechanism of Th2 cell-specific expression of IL-24, we identified a proximal promoter region (-157/+95 bp) that plays critical role in activating the IL-24 gene in Th2 cells. This region has a Th2 cell-specific open chromatin structure along with permissive histone modifications. In vivo binding of Stat6 and AP-1 (c-Jun) to the IL-24 promoter locus in Th2 cells synergistically transactivated the IL-24 promoter. Stat6 and c-Jun proteins were found to physically cooperate with each other and upregulated IL-24 gene transcription. Knockdown of either Stat6 or c-Jun suppressed endogenous IL-24 gene expression in Th2 cells. In summary, TCR stimulation induces IL-24 expression in Th2 cells by the coordinate action of Stat6 and c-Jun transcription factors at the transcriptional level.
21261551 Evidence-based tailored conservative treatment of knee and hip osteoarthritis: between kno 2011 May OBJECTIVE: Insufficient data are available on the efficacy of combined conservative interventions recommended by treatment guidelines for knee/hip osteoarthritis (OA). The aims of this observational cohort study were (i) to estimate the results of an evidence-based 12-week tailored multimodal conservative treatment protocol for patients with knee/hip OA and (ii) to identify predictors for response. METHODS: After obtaining data on previous OA-related interventions, multimodal treatment was offered to patients with knee and/or hip OA at a specialized outpatient clinic. Treatment with analgesics was tailored using a numeric rating scale (NRS) for pain, aiming for NRS ≤ 4. The following outcome measures were assessed: (i) the proportion of patients fulfilling OMERACT-OARSI (Outcome Measures in Rheumatoid Arthritis Clinical Trials/Osteoarthritis Research Society International) responder criteria and (ii) the proportion of patients with NRS pain ≤ 4 after 12 weeks. RESULTS: A total of 183 out of 299 patients was included. OMERACT-OARSI responder criteria were fulfilled at 12 weeks in 47% of patients; 39% reached NRS pain ≤ 4. The only independent predictor for response was the number of previously used non-steroidal anti-inflammatory drugs (NSAIDs). The majority of patients had not been exposed adequately to conservative treatment modalities for knee and/or hip OA in the past (81%). CONCLUSION: Evidence-based multimodal conservative treatment using a standardized protocol for knee and/or hip OA is feasible and successful in 47% of patients. In general, response could not be predicted. Basic first-line recommended conservative treatment options have not been used adequately prior to referral to secondary care in the vast majority of patients.
21249125 Macrophage activation and differentiation signals regulate schlafen-4 gene expression: evi 2011 Jan 7 BACKGROUND: The ten mouse and six human members of the Schlafen (Slfn) gene family all contain an AAA domain. Little is known of their function, but previous studies suggest roles in immune cell development. In this report, we assessed Slfn regulation and function in macrophages, which are key cellular regulators of innate immunity. METHODOLOGY/PRINCIPAL FINDINGS: Multiple members of the Slfn family were up-regulated in mouse bone marrow-derived macrophages (BMM) by the Toll-like Receptor (TLR)4 agonist lipopolysaccharide (LPS), the TLR3 agonist Poly(I∶C), and in disease-affected joints in the collagen-induced model of rheumatoid arthritis. Of these, the most inducible was Slfn4. TLR agonists that signal exclusively through the MyD88 adaptor protein had more modest effects on Slfn4 mRNA levels, thus implicating MyD88-independent signalling and autocrine interferon (IFN)-β in inducible expression. This was supported by the substantial reduction in basal and LPS-induced Slfn4 mRNA expression in IFNAR-1⁻/⁻ BMM. LPS causes growth arrest in macrophages, and other Slfn family genes have been implicated in growth control. Slfn4 mRNA levels were repressed during macrophage colony-stimulating factor (CSF-1)-mediated differentiation of bone marrow progenitors into BMM. To determine the role of Slfn4 in vivo, we over-expressed the gene specifically in macrophages in mice using a csf1r promoter-driven binary expression system. Transgenic over-expression of Slfn4 in myeloid cells did not alter macrophage colony formation or proliferation in vitro. Monocyte numbers, as well as inflammatory macrophages recruited to the peritoneal cavity, were reduced in transgenic mice that specifically over-expressed Slfn4, while macrophage numbers and hematopoietic activity were increased in the livers and spleens. CONCLUSIONS: Slfn4 mRNA levels were up-regulated during macrophage activation but down-regulated during differentiation. Constitutive Slfn4 expression in the myeloid lineage in vivo perturbs myelopoiesis. We hypothesise that the down-regulation of Slfn4 gene expression during macrophage differentiation is a necessary step in development of this lineage.
21062852 Effectiveness of switching between TNF inhibitors in ankylosing spondylitis: data from the 2011 Jan OBJECTIVE: To assess the effectiveness of switching to a second tumour necrosis factor inhibitor (TNFi) in patients with ankylosing spondylitis (AS). METHODS: Data were extracted from an ongoing longitudinal observational multicentre study in Norway. This study included anti-TNF naïve patients with AS starting treatment with a TNFi as well as treatment with a second TNFi in these same patients. Effectiveness data and 2-year drug survival were compared between switchers and non-switchers and within switchers (first and second TNFi). RESULTS: 514 anti-TNF naïve patients with AS were included; 77 patients switched to a second TNFi while 437 patients did not switch. The percentages of non-switchers using etanercept, infliximab or adalimumab were 53%, 32% and 15%, and the percentages of first and second TNFi in the switchers were 42%, 53% and 5% and 40%, 23% and 36%, respectively. The reason for switching was insufficient response (IR) in 30, adverse events (AEs) in 44 and not reported in 3 patients. Baseline disease activity was similar between the groups. Three-month BASDAI 50 and ASAS 40 responses were achieved by 49% and 38% of non-switchers, by 25% and 30% of switchers after the first TNFi and by 28% and 31% after the second TNFi. The 3-month disease activity level was higher for switchers on the second TNFi than for non-switchers. Drug withdrawal rate was higher during the second TNFi among switchers than for non-switchers (p=0.001). No difference was found in the effectiveness of the second TNFi between switchers due to IR and AE. CONCLUSION: This study confirms that switching to a second TNFi can be effective in AS and can be as useful as in rheumatoid arthritis, although overall effectiveness seems to be somewhat lower than in non-switchers.
22760290 Association between vaccination for herpes zoster and risk of herpes zoster infection amon 2012 Jul 4 CONTEXT: Based on limited data, the live attenuated herpes zoster (HZ) vaccine is contraindicated in patients taking anti-tumor necrosis factor (anti-TNF) therapies or other biologics commonly used to treat immune-mediated diseases. The safety and effectiveness of the vaccine are unclear for these patients. OBJECTIVE: To examine the association between HZ vaccination and HZ incidence within and beyond 42 days after vaccination in patients with selected immune-mediated diseases and in relation to biologics and other therapies used to treat these conditions. DESIGN, SETTING, AND PATIENTS: Retrospective cohort study of 463,541 Medicare beneficiaries 60 years and older with rheumatoid arthritis, psoriasis, psoriatic arthritis, ankylosing spondylitis, or inflammatory bowel disease using Medicare claims data from January 1, 2006, through December 31, 2009. MAIN OUTCOME MEASURES: Herpes zoster incidence rate within 42 days after vaccination (a safety concern) and beyond 42 days; hazard ratios estimated using Cox proportional hazards models for HZ comparing vaccinated vs unvaccinated patients. RESULTS: Median duration of follow-up was 2.0 years (interquartile range, 0.8-3.0); 4.0% of patients received HZ vaccine. The overall crude HZ incidence rate was 7.8 cases per 1000 person-years (95% CI, 3.7-16.5) within 42 days after vaccination. The rate among the unvaccinated was 11.6 cases per 1000 person-years (95% CI, 11.4-11.9). Among 633 patients exposed to biologics at the time of vaccination or within the subsequent 42 days, no case of HZ or varicella occurred. After multivariable adjustment, HZ vaccination was associated with a hazard ratio of 0.61 (95% CI, 0.52-0.71) for HZ risk after 42 days. CONCLUSIONS: Receipt of HZ vaccine was not associated with a short-term increase in HZ incidence among Medicare beneficiaries with selected immune-mediated diseases, including those exposed to biologics. The vaccine was associated with a lower HZ incidence over a median of 2 years of follow-up.
22249448 TNF-induced osteoclastogenesis and inflammatory bone resorption are inhibited by transcrip 2012 Feb 13 Tumor necrosis factor (TNF) plays a key role in the pathogenesis of inflammatory bone resorption and associated morbidity in diseases such as rheumatoid arthritis and periodontitis. Mechanisms that regulate the direct osteoclastogenic properties of TNF to limit pathological bone resorption in inflammatory settings are mostly unknown. Here, we show that the transcription factor recombinant recognition sequence binding protein at the J(κ) site (RBP-J) strongly suppresses TNF-induced osteoclastogenesis and inflammatory bone resorption, but has minimal effects on physiological bone remodeling. Myeloid-specific deletion of RBP-J converted TNF into a potent osteoclastogenic factor that could function independently of receptor activator of NF-κB (RANK) signaling. In the absence of RBP-J, TNF effectively induced osteoclastogenesis and bone resorption in RANK-deficient mice. Activation of RBP-J selectively in osteoclast precursors suppressed inflammatory osteoclastogenesis and arthritic bone resorption. Mechanistically, RBP-J suppressed induction of the master regulator of osteoclastogenesis (nuclear factor of activated T cells, cytoplasmic 1) by attenuating c-Fos activation and suppressing induction of B lymphocyte-induced maturation protein-1, thereby preventing the down-regulation of transcriptional repressors such as IRF-8 that block osteoclast differentiation. Thus, RBP-J regulates the balance between activating and repressive signals that regulate osteoclastogenesis. These findings identify RBP-J as a key upstream negative regulator of osteoclastogenesis that restrains excessive bone resorption in inflammatory settings.
21519345 IL-6 promotes acute and chronic inflammatory disease in the absence of SOCS3. 2012 Jan The lack of expression of the suppressor of cytokine signalling-3 (SOCS3) or inactivation of the negative regulatory capacity of SOCS3 has been well documented in rheumatoid arthritis, viral hepatitis and cancer. The specific qualitative and quantitative consequences of SOCS3 deficiency on interleukin-6 (IL-6)-mediated pro- and anti-inflammatory responses remain controversial in vitro and unknown in vivo. Mice with a conditional deletion of SOCS3 in hematopoietic cells develop lethal inflammatory disease during adult life and develop gross histopathological changes during experimental arthritis, typified by elevated IL-6 levels. To clarify the nature of the IL-6 responses in vivo, we generated mice deficient in SOCS3 (SOCS3(-/Δvav)) or both SOCS3 and IL-6 (IL-6(-/-)/SOCS3(-/Δvav)), and examined responses in models of acute and chronic inflammation. Acute responses to IL-1β were lethal to SOCS3(-/Δvav) mice but not IL-6(-/-)/SOCS3(-/Δvav) mice, indicating that IL-6 was required for the lethal inflammation induced by IL-1β. Administration of IL-1β to SOCS3(-/Δvav) mice induced systemic apoptosis of lymphocytes in the thymus, spleen and lymph nodes that was dependent on the presence of IL-6. IL-6 deficiency prolonged survival of SOCS3(-/Δvav) mice and ameliorated spontaneous inflammatory disease developing during adult life. Infection of SOCS3(-/Δvav) mice with LCMV induced a lethal inflammatory response that was dependent on IL-6, despite SOCS3(-/Δvav) mice controlling viral replication. We conclude that SOCS3 is required for survival during inflammatory responses and is a critical regulator of IL-6 in vivo.
21569519 Safety and clinical outcomes of rituximab therapy in patients with different autoimmune di 2011 May 13 INTRODUCTION: Evidence from a number of open-label, uncontrolled studies has suggested that rituximab may benefit patients with autoimmune diseases who are refractory to standard-of-care. The objective of this study was to evaluate the safety and clinical outcomes of rituximab in several standard-of-care-refractory autoimmune diseases (within rheumatology, nephrology, dermatology and neurology) other than rheumatoid arthritis or non-Hodgkin's lymphoma in a real-life clinical setting. METHODS: Patients who received rituximab having shown an inadequate response to standard-of-care had their safety and clinical outcomes data retrospectively analysed as part of the German Registry of Autoimmune Diseases. The main outcome measures were safety and clinical response, as judged at the discretion of the investigators. RESULTS: A total of 370 patients (299 patient-years) with various autoimmune diseases (23.0% with systemic lupus erythematosus, 15.7% antineutrophil cytoplasmic antibody-associated granulomatous vasculitides, 15.1% multiple sclerosis and 10.0% pemphigus) from 42 centres received a mean dose of 2,440 mg of rituximab over a median (range) of 194 (180 to 1,407) days. The overall rate of serious infections was 5.3 per 100 patient-years during rituximab therapy. Opportunistic infections were infrequent across the whole study population, and mostly occurred in patients with systemic lupus erythematosus. There were 11 deaths (3.0% of patients) after rituximab treatment (mean 11.6 months after first infusion, range 0.8 to 31.3 months), with most of the deaths caused by infections. Overall (n = 293), 13.3% of patients showed no response, 45.1% showed a partial response and 41.6% showed a complete response. Responses were also reflected by reduced use of glucocorticoids and various immunosuppressives during rituximab therapy and follow-up compared with before rituximab. Rituximab generally had a positive effect on patient well-being (physician's visual analogue scale; mean improvement from baseline of 12.1 mm). CONCLUSIONS: Data from this registry indicate that rituximab is a commonly employed, well-tolerated therapy with potential beneficial effects in standard of care-refractory autoimmune diseases, and support the results from other open-label, uncontrolled studies.
20962030 The fate and function of therapeutic antiaddiction monoclonal antibodies across the reprod 2011 Feb During preclinical development of neuroprotective antiaddiction therapeutic monoclonal antibodies (mAbs) against phencyclidine (PCP) and (+)-methamphetamine, we discovered novel, gestation stage-specific changes in mAb disposition spanning the entire reproductive cycle of female rats. Each pharmacological change was independent of mAb dose and antigen target but was precisely coincident with transitions between the gestational trimesters, parturition, and lactation periods of the female reproductive cycle. Whereas anti-PCP mAb6B5 terminal elimination half-life (t(1/2λz)) in nonpregnant females was 6.6 ± 1.6 days, the mAb6B5 t(1/2λz) significantly changed to 3.7 ± 0.4 days, then 1.4 ± 0.1 days, then 3.0 ± 0.4 days in the second trimester, third trimester, and postpartum periods, respectively (p < 0.05 for each change). Initially, these evolving changes in mAb6B5 clearance (3.3-fold), distribution volume (1.8-fold), and elimination half-life (4.7-fold) affected our ability to sustain sufficient mAb6B5 levels to sequester PCP in the bloodstream. However, understanding the mechanisms underlying each transition allowed development of an adaptive mAb-dosing paradigm, which substantially reduced PCP levels in dam brains and fetuses throughout pregnancy. These mAb functional studies also revealed that antidrug mAbs readily cross the placenta before syncytiotrophoblast barrier maturation, demonstrating the dynamic nature of mAb pharmacokinetics in pregnancy and the importance of maintaining maternal mAb levels. These studies provide the first preclinical pregnancy model in any species for chronic mAb dosing and could have important implications for the use of antibody therapies involving blood organ barriers (such as addiction) or other chronic diseases in women of childbearing age (e.g., irritable bowel diseases, multiple sclerosis, breast cancer, rheumatoid arthritis).
21915551 Total joint arthroplasty in patients with hepatitis C. 2011 Aug 3 BACKGROUND: Hepatitis C is present worldwide. Little is known about the outcome of joint arthroplasty in asymptomatic patients with hepatitis C. We evaluated the surgical complications following hip and knee arthroplasty in patients who were seropositive for hepatitis C in a matched study. METHODS: Seventy-one patients with hepatitis C underwent forty total hip arthroplasties and thirty-two total knee arthroplasties from 1995 to 2006. The patients had normal preoperative liver function tests. Patients with human immunodeficiency virus infection, hepatitis B, and hemophilia were excluded. A control group was matched in a 2:1 ratio with the hepatitis-C group for age, body-mass index, sex, year of surgery, and medical comorbidities, including diabetes, rheumatoid arthritis, and immunosuppressive conditions. RESULTS: In the group of patients with hepatitis C who were managed with total hip arthroplasty, six patients (15%) had wound complications requiring oral antibiotics or wound irrigation and debridement and four hips (10%) had mechanical complications, including implant loosening or dislocation. In the control group, three patients (3.8%) had wound complications requiring oral antibiotics or irrigation and debridement and three patients (3.8%) had mechanical complications, including dislocation, periprosthetic femoral fracture, and implant failure. In the group of patients with hepatitis C who underwent total knee arthroplasty, three patients (9.4%) had mechanical complications, including loosening and periprosthetic fracture requiring revision. In the control group, three patients (4.7%) had wound complications, one (1.6%) had a deep infection requiring two-stage revision, and one (1.6%) underwent revision because of a mechanical problem. The combined hepatitis-C group had significantly longer hospital stays and higher rates of surgical and mechanical complications, reoperation, and revision. CONCLUSIONS: Patients with hepatitis C undergoing joint arthroplasty had a higher rate of surgical complications and a longer hospital stay. The reason for the higher rate of complications in this group of patients is unknown, and further investigation is needed. Patients with hepatitis C should be counseled about the potential for a higher incidence of postoperative complications prior to undergoing joint arthroplasty.
21733463 Correction of rigid equinovarus deformity using a multiplanar external fixator. 2011 May BACKGROUND: The rigid equinovarus foot deformity is a challenging condition treated by the orthopaedic foot and ankle surgeon. Rapid surgical correction of the deformity may lead to skin and neurologic complications. Gradual correction of the deformity with a multiplanar external fixator may decrease these complications. The purpose of this study was to present the results of a group of patients with rigid equinovarus deformities corrected using a multiplanar external fixator. MATERIALS AND METHODS: We retrospectively reviewed the results of correction of a rigid equinovarus deformity using multiplanar external fixation in a small group of patients. All patients underwent open Achilles lengthening, posterior capsule release, tibialis posterior tendon lengthening, flexor digitorum longus and flexor hallux longus lengthening, followed by application of a multiplanar external fixator with gradual correction of the deformity over a period of several weeks. Preoperative and postoperative deformity and AOFAS ankle-hindfoot scores were assessed. RESULTS: A total of eight rigid equinovarus deformities in six patients were treated with a multiplanar external fixator. The average patient age at the time of surgery was 37.2 (range, 17 to 59 ± 15.0) years. Causes of the deformity included trauma in three patients, traumatic brain injury in two patients, and long-standing rheumatoid arthritis in one patient. The average preoperative AOFAS ankle-hindfoot score was 28.3 (range, 12 to 38 ± 7.7). The average postoperative AOFAS ankle-hindfoot score was 68.1 (range 38 to 86 ± 15.5) at an average followup of 71.9 (30 to 120 ± 36.2) weeks. All deformities were gradually corrected to a plantigrade foot using a multiplanar external fixator over an average time of 5 (range, 4 to 6 ± 0.8) weeks. After correction of the deformity, the external fixator was left in place for a time period equal to or twice the length of time it took to achieve correction. The average duration of external fixation was 10.8 (range, 8 to 16 ± 2.8) weeks. Seven of eight deformities maintained correction at final followup. There was one case of recurrence. CONCLUSION: Correction of a rigid equinovarus deformity using a multiplanar external fixator was a viable treatment option. It allowed for correction of the deformity in a controlled manner, helping to reduce the risk of neurovascular complications that may result from single stage surgical correction. The risk of wound complications still exists with the correction of such a complex deformity.