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Background As COVID-19 immunomodulation has been a part of interest for studies, it has been found that severe coronavirus disease 2019 (COVID-19) is associated with hyper-inflammatory response and increased levels of interleukin-6 (IL-6) and interleukin-10 (IL-10). This can progress to cytokine storm syndrome and eventually development of acute respiratory distress syndrome (ARDS). Interleukin-1 receptor antagonist (IL-1RA) is a protein that is a member of the interleukin 1 cytokine family. Monocyte chemoattractant protein 1 (MCP1) is a small cytokine that belongs to the CC chemokine family. Interferon gamma-induced protein 10 (IP-10) is a protein secreted by several cell types in response to Interferon-Gamma (IFN-γ). All of these have roles in the immune response and eventually development of a cytokine storm. Methods Serum levels of IL-1RA, MCP-1 and IP-10 were measured in a cohort of 21 patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on admission to a tertiary care hospital in Riyadh, Saudi Arabia, as well as in an approximately age-sex matched group of 4 uninfected controls. The study population was classified into severe, moderate, mild and controls. Results Serum levels of IL-1RA, MCP-1 and IP-10 were found to be elevated before the clinical deterioration. Conclusion These cytokines may play a role in early detection of disease severity especially in the pre-storm phase. Medications that target cytokines may prevent the development of an overt cytokine storm.

The limited availability of human donor organs suitable for transplantation has resulted in ever-increasing patient waiting lists globally. Xenotransplantation is considered a potential option, but is yet to reach clinical practice. Although remarkable progress has been made in overcoming immunological rejection, issues with functionality are still to be resolved. Bioengineering approaches have been used to create cardiac tissues with optimized functions. The use of decellularized xenogeneic cardiac tissues seeded with donor-derived cardiac cells may prove to be a viable strategy as supporting structures of the native tissue such as vasculature can be utilized. Here we used sequential perfusion to decellularize adult rat hearts. The acellular scaffolds were reseeded with human endothelial cells, human fibroblasts, human mesenchymal stem cells, and cardiac cells derived from human-induced pluripotent stem cells. The ability of the resultant recellularized rat scaffolds to activate human naïve neutrophils in vitro was investigated to measure xenogeneic recognition. Our results demonstrate that in contrast to cadaveric xenogeneic hearts, acellular and recellularized xenogeneic scaffolds did not activate human naïve neutrophils and suggest that decellularization removes the xenogeneic antigens that lead to human naïve neutrophil activation thus allowing human cells to populate the now "allogenized" xenogeneic scaffolds.

Aims Hypoxia-induced adipokine release has been attributed mainly to HIF-1α. Here we investigate the role of intracellular calcium and NF-kB in the hypoxia-dependent release of leptin, VEGF, IL-6 and the hypoxia-induced inhibition of adiponectin release in human adipocytes. Main methods We used intracellular calcium imaging to compare calcium status in preadipocytes and in adipocytes. We subjected both cell types to hypoxic conditions and measured the release of adipokines induced by hypoxia in the presence and absence of HIF-1α inhibitor YC-1, NF-κB inhibitor SN50 and intracellular calcium chelator BAPTA-AM. Key findings We demonstrate reduced intracellular calcium oscillations and increased oxidative stress as the cells transitioned from preadipocytes to adipocytes. We show that differentiation of preadipocytes to adipocytes is associated with distinct morphological changes in the mitochondria. We also show that hypoxia-induced secretion of leptin, VEGF, IL-6 and hypoxia-induced inhibition of adiponectin secretion are independent of HIF-1α expression. The hypoxia-induced leptin, VEGF and IL-6 release are [Ca++]i dependent whereas adiponectin is NF-kB dependent. Significance Our work suggests a major role for [Ca++]i in preadipocyte differentiation to adipocytes and that changes in mitochondrial morphology in the adipocytes might underlie the reduced calcium oscillations observed in the adipocytes. It also demonstrates that multiple signaling pathways are associated with the hypoxia-induced adipokine secretion.

The data set presented here is associated with the article “Intracellular calcium and NF-kB regulate hypoxia-induced leptin, VEGF, IL-6 and adiponectin secretion in human adipocytes” (Al-Anazi et al., 2018). Data illustrate hypoxia-induced VEGF and leptin expression in human adipocytes treated with the calcium chelator BAPTA-AM (1 µM). It also shows NF-κB p65 induced expression by hypoxia. Preadipocytes were differentiated for 14 days and then subjected to 0.5–1.5% oxygen in the presence and absence of BAPTA-AM or the NF-κB inhibitor SN50 for 48 h prior to RNA isolation and PCR analysis.

Background Pulmonary fibrosis is one of the leading indications for lung transplantation. The disease, which is of unknown aetiology, can be progressive, resulting in distortion of the extracellular matrix (ECM), inflammation, fibrosis and eventual death. Methods 13 patients born to consanguineous parents from two unrelated families presenting with interstitial lung disease were clinically investigated. Nine patients developed respiratory failure and subsequently died. Molecular genetic investigations were performed on patients' whole blood or archived tissues, and cell biological investigations were performed on patient-derived fibroblasts. Results The combination of a unique pattern of early-onset lung fibrosis (at 12–15 years old) with distinctive radiological findings, including 1) traction bronchiectasis, 2) intralobular septal thickening, 3) shrinkage of the secondary pulmonary lobules mainly around the bronchovascular bundles and 4) early type 2 respiratory failure (elevated blood carbon dioxide levels), represents a novel clinical subtype of familial pulmonary fibrosis. Molecular genetic investigation of families revealed a hypomorphic variant in S100A3 and a novel truncating mutation in S100A13, both segregating with the disease in an autosomal recessive manner. Family members that were either heterozygous carriers or wild-type normal for both variants were unaffected. Analysis of patient-derived fibroblasts demonstrated significantly reduced S100A3 and S100A13 expression. Further analysis demonstrated aberrant intracellular calcium homeostasis, mitochondrial dysregulation and differential expression of ECM components. Conclusion Our data demonstrate that digenic inheritance of mutations in S100A3 and S100A13 underlie the pathophysiology of pulmonary fibrosis associated with a significant reduction of both proteins, which suggests a calcium-dependent therapeutic approach for management of the disease., New evidence links an atypical form of pulmonary fibrosis with digenic mutations in the genes for calcium binding proteins S100A3 and S100A13. This implicates calcium homeostasis in the aetiology and pathogenesis of pulmonary fibrosis. http://bit.ly/2LyUQwb

β2-microglobulin (β2-m), a 11.8 kDa protein, pairs non-covalently with the α3 domain of the major histocompatibility class (MHC) I α-chain and is essential for the conformation of the MHC class I protein complex. Shed β2-m is measurable in circulation, and various disorders are accompanied by increases in β2-m levels, including several viral infections. Therefore, we explored whether β2-m levels could also be elevated in Coronavirus disease 2019 (Covid-19) and whether they predict disease severity. Serum β2-m levels were measured in a cohort of 34 patients infected with SARS-CoV-2 on admission to a tertiary care hospital in Riyadh, Saudi Arabia, as well as in an approximately age-sex matched group of 34 uninfected controls. Mean β2-m level was 3.25±1.68 mg/l (reference range 0.8–2.2 mg/l) in patients (mean age 48.2±21.6) and 1.98±0.61 mg/l in controls (mean age 48.2±21.6). 17 patients (mean age 36.9± 18.0) with mean β2-m levels of 2.27±0.64 mg/l had mild disease by WHO severity categorization, 12 patients (mean age 53.3±18.1) with mean β2-m levels of 3.57±1.39 mg/l had moderate disease, and five patients (of whom 2 died; mean age 74.4±13.8) with mean β2-m levels of 5.85±1.85 mg/l had severe disease (P < = 0.001, by ANOVA test for linear trend). In multivariate ordinal regression β2-m levels were the only significant predictor of disease severity. Our findings suggest that higher β2-m levels could be an early indicator of severity of disease and predict outcome of Covid-19. As the main limitations of the study are a single-center study, sample size and ethnicity, these results need confirmation in larger cohorts outside the Arabian Peninsula in order to delineate the value of β2-m measurements. The role of β2-m in the etiology and pathogenesis of severe Covid-19 remains to be elucidated.

Hypoxia-induced adipokine release has been attributed mainly to HIF-1α. Here we investigate the role of intracellular calcium and NF-kB in the hypoxia-dependent release of leptin, VEGF, IL-6 and the hypoxia-induced inhibition of adiponectin release in human adipocytes.We used intracellular calcium imaging to compare calcium status in preadipocytes and in adipocytes. We subjected both cell types to hypoxic conditions and measured the release of adipokines induced by hypoxia in the presence and absence of HIF-1α inhibitor YC-1, NF-We demonstrate reduced intracellular calcium oscillations and increased oxidative stress as the cells transitioned from preadipocytes to adipocytes. We show that differentiation of preadipocytes to adipocytes is associated with distinct morphological changes in the mitochondria. We also show that hypoxia-induced secretion of leptin, VEGF, IL-6 and hypoxia-induced inhibition of adiponectin secretion are independent of HIF-1α expression. The hypoxia-induced leptin, VEGF and IL-6 release are [CaOur work suggests a major role for [Ca

Growing evidence indicates a link between persistent infections and the development of autoimmune diseases. For instance, the inability to control Salmonella infection due to defective toll-like receptor (TLR) / myeloid differentiation primary response 88 (MyD88) signaling has linked the development of persistent infections to a breakdown in B cell tolerance. However, the extent of immune dysregulation in the absence of TLR-MyD88 signaling remains poorly characterized. Here, we show that MyD88-/- mice areGrowing evidence indicates a link between persistent infections and the development of autoimmune diseases. For instance, the inability to control Salmonella infection due to defective toll-like receptor (TLR) / myeloid differentiation primary response 88 (MyD88) signaling has linked the development of persistent infections to a breakdown in B cell tolerance. However, the extent of immune dysregulation in the absence of TLR-MyD88 signaling remains poorly characterized. Here, we show that MyD88-/- mice are unable to eliminate attenuated Salmonella enterica serovar Typhimurium, even when challenged with a low dose inoculum (200 CFUs/mouse), developing a persistent and progressive infection when compared to wild-type (MyD88+/+) animals. The splenic niche of MyD88-/- mice revealed increased counts of activated, Sca-1-positive, myeloid subpopulations highly expressing BAFF during persistent Salmonella infection. Likewise, the T cell compartment of Salmonella-infected MyD88-/- mice showed increased levels of CD4+ and CD8+ T cells expressing Sca-1 and CD25 and producing elevated amounts of IL-4, IL-10 and IL-21 in response to CD3/CD28 stimulation. This was associated with increased Tfh cell differentiation and the presence of CD4+ T cells co-expressing IFN-/IL-4 and IFN-/IL-10. Noteworthy, infected MyD88-/- mice had enhanced serum titers of both anti-Salmonella antibodies as well as autoantibodies directed against dsDNA, thyroglobulin and IgG rheumatoid factor (RF), positive nuclear staining with HEp2 cells, and immune complex deposition in the kidneys of MyD88-/- mice infected with live but not heat-killed Salmonella. Infection with other microorganisms (Acinetobacter baumanii, Streptococcus agalactiae or Escherichia coli) was unable to trigger the autoimmune phenomenon. Our findings suggest that dysregulation of the immune response in the absence of MyD88 is pathogen-dependent and highlight potentially important genotype-environmental factor correlations.

Background Lipid metabolism dysfunction leading to excess fat deposits (obesity) may cause tumor (cancer) development. Both obesity and cancer are the epicenter of important medical issues. Lipid metabolism and cell death/proliferation are controlled by biochemical and molecular pathways involving many proteins, and organelles; alteration in these pathways leads to fat accumulation or tumor growth. Mammalian Kruppel-like factors, KLFs play key roles in both lipid metabolism and tumor development. Scope of review Substantial epidemiological and clinical studies have established strong association of obesity with a number of human cancers. However, we need more experimental verification to determine the exact role of this metabolic alteration in the context of tumor development. A clear understanding of molecules, pathways and the mechanisms involved in lipid metabolism and cell death/proliferation will have important implications in pathogenesis, and prevention of these diseases. Major conclusion The regulatory role of KLFs, in both cell death/proliferation and lipid metabolism suggests a common regulation of both processes. This provides an excellent model for delivering a precise understanding of the mechanisms linking altered expression of KLFs to obesity and tumor development. General significance Currently, mouse and rats are the models of choice for investigating disease mechanisms and pharmacological therapies but a genetic model is needed for a thorough examination of KLF function in vivo during the development of an organism. The worm Caenorhabditis elegans is an ideal model to study the connectivity between lipid metabolism and cell death/proliferation.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is characterized as inflammation of small-sized to medium-sized blood vessels and encompasses several clinicopathologic entities including granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, and renal-limited ANCA-associated vasculitis. Over the past several decades, significant progress has been made in understanding the pathophysiology of ANCA-associated vasculitis. Although neutrophils contain a multitude of granular proteins, clinically significant autoantibodies are only recognized against myeloperoxidase and proteinase 3, both of which are present in the azurophilic granules. The propensity to develop these antibodies depends on a variety of predisposing factors such as microbial infection, genetic factors, environmental agents, and therapeutic drugs among others. These factors are usually associated with production of proinflammatory cytokines with capacity to prime the neutrophils. As a result a high proportion of neutrophils in circulation may be primed resulting in exposure of cytoplasmic proteins including myeloperoxidase and proteinase 3 on the surface of the neutrophils. Primed neutrophils are activated by interaction with ANCA in circulation. Activated neutrophils attach to and transmigrate through endothelium and accumulate within the vessel wall. These neutrophils degranulate and produce reactive oxygen radicals and ultimately die, causing tissue injury. Endothelial injury results in leakage of serum proteins and coagulation factors causing fibrinoid necrosis. B cells produce ANCAs, as well as neutrophil abnormalities and imbalances in different T-cell subtypes with excess of Th17, which perpetuate the inflammatory process.

BackgroundPulmonary fibrosis is one of the leading indications for lung transplantation. The disease, which is of unknown aetiology, can be progressive, resulting in distortion of the extracellular matrix (ECM), inflammation, fibrosis and eventual death.Methods13 patients born to consanguineous parents from two unrelated families presenting with interstitial lung disease were clinically investigated. Nine patients developed respiratory failure and subsequently died. Molecular genetic investigations were performed on patients' whole blood or archived tissues, and cell biological investigations were performed on patient-derived fibroblasts.ResultsThe combination of a unique pattern of early-onset lung fibrosis (at 12–15 years old) with distinctive radiological findings, including 1) traction bronchiectasis, 2) intralobular septal thickening, 3) shrinkage of the secondary pulmonary lobules mainly around the bronchovascular bundles and 4) early type 2 respiratory failure (elevated blood carbon dioxide levels), represents a novel clinical subtype of familial pulmonary fibrosis. Molecular genetic investigation of families revealed a hypomorphic variant in S100A3 and a novel truncating mutation in S100A13, both segregating with the disease in an autosomal recessive manner. Family members that were either heterozygous carriers or wild-type normal for both variants were unaffected. Analysis of patient-derived fibroblasts demonstrated significantly reduced S100A3 and S100A13 expression. Further analysis demonstrated aberrant intracellular calcium homeostasis, mitochondrial dysregulation and differential expression of ECM components.ConclusionOur data demonstrate that digenic inheritance of mutations in S100A3 and S100A13 underlie the pathophysiology of pulmonary fibrosis associated with a significant reduction of both proteins, which suggests a calcium-dependent therapeutic approach for management of the disease.

Lipopolysaccharide-responsive, beige-like anchor protein (LRBA) deficiency causes common variable immunodeficiency (CVID) disorders and autoimmunity. LRBA deficiency has become a clinically variable syndrome with a wide spectrum of clinical manifestations. We report a patient with LRBA deficiency associated chronic non-erosive arthritis. This report highlights the spectrum of arthritis in such patients and the potential causative role of LRBA gene in juvenile arthritis.

Background: Recent recommendations have established clinical remission ideally or low disease activity (LDA) as therapeutic targets in all patients with rheumatoid arthritis (RA). Controlled studies of biologic agents have primarily assessed treatment effects in patients with severe RA; patients with moderate disease activity, whoconstitute a larger group, have received far less attention. In Period 1 of the PRESERVE trial, the proportion of subjects with moderately active RA achieving LDA or remission were evaluated after treatment with etanercept 50mg once weekly (QW) plus methotrexate for 36 weeks.Methods: Subjects with DAS28 >3.2 and ≤5.1 despite stable doses of oral methotrexate received open-label etanercept 50mg QW plus methotrexate (screening dose permitted to be titrated up to 25 mg/wk through week 28) for 36 weeks.Results: 834 subjects received treatment and were analyzed. Subjects were mostly female (83%), Caucasian (74%), RFþ (73%), and aCCPþ (78%), with a mean age of 48 years and disease duration of 7 years. Mean baseline DAS28 was 4.4; SDAI, 19.1; ESR, 22.2 mm/hr; and CRP, 12.3 mg/L. Efficacy results from Period 1 are shown in the table. The most commonly reported adverse events (AEs) were headache (6.1%), nasopharyngitis (5.4%), and upper respiratory tract infection (4.4%). Twenty-two subjects (2.6%) discontinued due to AEs.Conclusions: Substantial proportions of subjects with moderately active RA who received etanercept 50mg QW plus methotrexate for 36 weeks achieved LDA (85%-86%), DAS28 remission (67%), or SDAI remission (25%). Therefore, these ambitious goals can be achieved realistically in a high percentage of patients with moderate disease activity.

A novel in vitro system was developed to investigate the effects of two forms of calcined mesoporous silica particles (MCM41-cal and SBA15-cal) on cellular respiration of mouse tissues. O(2) consumption by lung, liver, kidney, spleen, and pancreatic tissues was unaffected by exposure to 200 μg/mL MCM41-cal or SBA15-cal for several hours. Normal tissue histology was confirmed by light microscopy. Intracellular accumulation of the particles in the studied tissues was evident by electron microscopy. The results show reasonable in vitro biocompatibility of the mesoporous silicas with murine tissue bioenergetics.

We describe a flare of Behçet's syndrome in a 42-year-old man who presented with florid mucocutaneous manifestations, headache and vomiting, but without meningeal or neurologic signs. A single, non-enhancing cortical lesion was found in the frontal lobe by computed tomography and magnetic resonance (MR) imaging studies. Diffusion-weighted analysis and MR spectroscopy were consistent with focal inflammation. The patient improved with colchicine, and after 5 months, a repeat MR scan demonstrated resolution of the inflammatory changes suggesting that involvement of the cerebral cortex may be a self-limiting phenomenon, distinct from other more frequent and destructive parenchymal manifestations of neuro-Behçet's disease.

The molecular mechanisms underlying the geometrical changes of the left ventricle during the progression to heart failure and recovery are not well defined.Here we investigate the involvement of matrixins and cardiokines in an ovine model of pressure-induced left ventricular failure (LVF).Fifteen sheep underwent supracoronary aortic banding with an inflatable cuff. A controlled and progressive increase of LV pressure was monitored echocardiographically. Endomyocardial biopsies were collected throughout the development of LVF and subsequent recovery after pressure unloading.Thirteen sheep developed LVF with a subsequent recovery. Peak left ventricular hypertrophy (LVH) and dilatation (LVD) occurred at 31.5 ± 1.6 weeks and 102.7 ± 2.2 weeks post-banding respectively, with an increase in LV internal diameter in diastole (LVIDd 5.11 ± 0.12 compared to the control 3.37 ± 0.07 cm, p0.001), with preserved LV ejection fraction (LVEF). Reduced LVEF became evident 116.5 ± 2.7 weeks post-banding. Clinical and echocardiographic improvements were observed following deflation of the aortic banding cuff. By 138.1 ± 3.1 weeks cardiac performance recovered with restoration of LVEF. Significant changes in the expression of matrix metalloproteinases (MMP)-1, -2, -3, vascular endothelial cell growth factor (VEGF), fibroblast growth factor (FGF)-2, interferon (INF)-α-2 and soluble CD40 ligand (sCD40L) were observed throughout the progression to failure and recovery.We used an ovine model to study reversible LV remodelling without interruption and found significant changes in matrixin and cardiokine expression during LV progression to failure and recovery.

Purpose. To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis. Design and patients. Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically tested against each other. Results. The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of cartilage or cortical bone were detected. Conclusion. FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions in rheumatoid arthritis.

The response of human T lymphocytes to various stimuli includes the expression of the matrix metalloproteinase (MMP) genes stromelysin 2, gelatinase A and gelatinase B. The proteins encoded by these genes could confer the capacity to degrade macromolecular components of the extracellular matrix (ECM), and to shed transmembrane proteins such as tumor necrosis factor (TNF), TNF receptor, Interleukin-6 receptor and Fas ligand. To identify further MMP genes transcribed in T lymphocytes exposed to phorbol 12-myristate 13-acetate and a calcium ionophore, we combined reverse transcription and polymerase chain reaction using primers specific for conserved domains and detected collagenase 3 transcripts, first described in a human breast cancer. However, when the sequence of the complementary DNA was compared, additional 23 nucleotides were found in the 5' nontranslated region of the lymphocyte messenger RNA (mRNA). Northern blot analysis revealed 2 major inducible mRNA species of 1.9 and 2.8 kilobases, whose levels were lower than those of stromelysin 2. The observation that activated T lymphocytes transcribe several MMP genes, including a collagenase, indicates that the effector functions of these cells include enzymatic activities towards most constituents of the ECM, as well as some transmembrane proteins relevant to inflammation and apoptosis.

Significant immunological obstacles are to be negotiated before xenotransplantation becomes a clinical reality. An initial rejection of transplanted vascularized xenograft is attributed to Galα1,3Galβ1,4GlcNAc-R (Galα1,3-Gal)–dependent and –independent mechanisms. Hitherto, no receptor molecule has been identified that could account for Galα1,3-Gal–independent rejection. In this study, we identify the tetraspanin CD82 as a receptor molecule for the Galα1,3-Gal–independent mechanism. We demonstrate that, in contrast to human undifferentiated myeloid cell lines, differentiated cell lines are capable of recognizing xenogeneic porcine aortic endothelial cells in a calcium-dependent manner. Transcriptome-wide analysis to identify the differentially expressed transcripts in these cells revealed that the most likely candidate of the Galα1,3-Gal–independent recognition moiety is the tetraspanin CD82. Abs to CD82 inhibited the calcium response and the subsequent activation invoked by xenogeneic encounter. Our data identify CD82 on innate immune cells as a major “xenogenicity sensor” and open new avenues of intervention to making xenotransplantation a clinical reality.

Keratinocyte growth factor (KGF) has been implicated in wound re-epithelialization and branching morphogenesis of several organs. To determine whether KGF induces these effects via induction of matrix metalloproteinase expression we have analysed the effect of KGF on the expression of stromelysin-2 in cultured HaCaT keratinocytes. Here we show a strong induction of stromelysin-2 mRNA within 5–8 h of stimulation of these cells with KGF. The degree of induction was similar to that achieved by treatment with epidermal growth factor or tumour necrosis factor α, whereas the stimulatory effect of transforming growth factor β1 was even stronger. To determine whether the induction of stromelysin-2 expression by growth factors and cytokines might be important for wound healing, we analysed the expression of this gene during the healing process of full-thickness excisional wounds in mice. Whereas stromelysin-2 mRNA could hardly be detected in unwounded skin, a biphasic induction was seen after injury and highest levels were found at days 1 and 5 after wounding. Hybridization in situ revealed the presence of stromelysin-2 mRNA in basal keratinocytes at the wound edge but not in the underlying mesenchymal tissue. During impaired wound healing as seen in glucocorticoid-treated mice, stromelysin-2 expression was significantly increased compared with untreated control mice. Taken together, these results suggest that correct regulation of this broad-spectrum metalloproteinase might be important for normal repair.

Objective. T lymphocytes are known to interact with cellular and structural components of the extracellular matrix. We investigated whether T lymphocytes could also contribute to matrix breakdown by expression of a matrix metalloproteinase (MMP) gene. Methods. Complementary DNA (cDNA) was synthesized from messenger RNA extracted from cultured peripheral blood T lymphocytes after exposure to phorbol myristate acetate and calcium ionophore A23187 and amplified by the polymerase chain reaction with primers derived from two conserved domains in MMP genes. Results. An amplification product of 402 basepairs was generated and cloned; sequence analysis revealed identity to human stromelysin-2 cDNA. Using the amplified stromelysin-2 cDNA as a probe for Northern analyses, we detected a 1.8-kilobase transcript in stimulated T lymphocytes. Conclusion. T lymphocytes are a potential source of stromelysin-2 transcripts and may have a role in the degradation of extracellular matrix constituents.

To clarify mechanisms responsible for the self-limiting and nonerosive features of autoinflammatory joint disease in familial Mediterranean fever (FMF), we performed a study on synovial tissue obtained surgically from an acutely inflamed hip joint from a boy feared to have septic arthritis but later found to be homozygous for mutation M694I in pyrin/marenostrin. We defined by immunohistology the infiltrating cells and examined the in situ expression of plausible protagonists in synovitis of FMF: myeloperoxidase, lysozyme, galectin 1, galectin 3, p65 (RelA)/nuclear factor κB, inducible nitric-oxide synthase, cyclooxygenase 2, and cleaved caspase 3. Neutrophils deficient in myeloperoxidase and lysozyme, macrophages, and mast cells outnumbered T and B lymphocytes as well as plasma cells. Among cells of adaptive immunity, B lymphocytes were predominant. Galectin 1 was detected in numerous cells of the innate immune system throughout the synovial tissue, whereas expression of galectin 3 was less abundant and scattered. p65 (RelA)/nuclear factor κB and inducible nitric-oxide synthase were both upregulated in most of the infiltrating cells. Cyclooxygenase 2 expression was low, and cleaved caspase 3 was undetectable. We conclude that the exquisitely inflammatory yet nondestructive character of FMF arthritis could correlate with the presence of nonpathogenic neutrophils lacking effector molecules and the widespread expression of anti-inflammatory galectin 1 in regulatory cells of the innate immune system. Intrinsic apoptosis seemed irrelevant for confining synovial autoinflammation, but regulation through pyroptosis or the adaptive immune system remains possible.

We report a 57-year-old man with acute thrombocytopenia, leucopenia, and multiorgan dysfunction. Patient was from North Korea and was temporarily working in Dubai, United Arab Emirates, when he fell ill in March 2009. At the same time and unknown to us, many patients with similar clinical manifestations were admitted to hospitals in China. The Chinese cases—identified between March and July 2009—were recently reported to have been infected with a tick-born strain of bunyavirus, a new disease. The virus infection was documented in patients from central China and the region that shares the border with North Korea. The clinical manifestations, the time of disease onset, and geographical link of the patient with the region in which the disease is endemic suggest that the patient had SFTS bunyavirus infection.

Introduction A novel in vitro system was developed to measure O2 consumption by murine tissues over several hours. Methods Tissue specimens (7–35 mg) excised from male Balb/c mice were immediately immersed in ice-cold Krebs–Henseleit buffer, saturated with 95% O2:5% CO2. The specimens were incubated at 37 °C in the buffer, continuously gassed with O2:CO2 (95:5). [O2] was determined as a function of time from the phosphorescence decay rates (1 / τ) of Pd(II) meso-tetra-(4-sulfonatophenyl)-tetrabenzoporphyrin. The values of 1 / τ were linear with [O2]: 1 / τ = 1/τo + kq [O2]; 1 / τo = the decay rate for zero O2, kq = the rate constant in s−1 μM−1. Results NaCN inhibited O2 consumption, confirming oxidation occurred in the mitochondrial respiratory chain. The rate of respiration in lung specimens incubated in vitro for 3.9 ≤ t ≤ 12.4 h was 0.24 ± 0.03 μM O2 min−1 mg−1 (mean ± SD, n = 28). The corresponding rate for the liver was 0.27 ± 0.13 (n = 11, t ≤ 4.7 h), spleen 0.28 ± 0.07 (n = 10, t ≤ 5 h), kidney 0.34 ± 0.12 (n = 7, t ≤ 5 h) and pancreas 0.35 ± 0.09 (n = 10, t ≤ 4 h). Normal tissue histology at hour 5 was confirmed by light and electron microscopy. There was negligible number of apoptotic cells by caspase 3 staining. Discussion This approach allows accurate assessment of tissue bioenergetics in vitro.

In this study, we investigated the expression patterns of 15 matrix metalloproteinases (MMPs) and three tissue inhibitors of metalloproteinase in gliomas, medulloblastomas, and normal brain tissue. By Northern blot analysis we found increased levels of mRNAs encoding for gelatinase A, gelatinase B, two membrane-type MMPs (mt1- and mt2-MMP), and tissue inhibitors of metalloproteinase-1 in glioblastomas and medulloblastomas. We observed a significant increase of mt1-MMP, gelatinase A, gelatinase B, and tissue inhibitors of metalloproteinase-1 in glioblastomas as compared with low-grade astrocytomas, anaplastic astrocytomas, and normal brain. In medulloblastomas, the expression of mt1-MMP, mt2-MMP, and gelatinase A were also increased, but to a lesser extent than that observed in glioblastomas. These data were confirmed at the protein level by immunostaining analysis. Moreover, substrate gel electrophoresis showed that the activated forms of gelatinases A and B were present in glioblastomas and medulloblastomas. These results suggest that increased expression of mt1-MMP/gelatinase A is closely related to the malignant progression observed in gliomas. Furthermore, the present study demonstrates, to our knowledge for the first time, that medulloblastomas express high levels of MMP.

Matrix metalloproteinases (MMP) are a family of structurally related endopeptidases that resorb macromolecules of the extracellular matrix (ECM)1. They are involved in normal tissue remodeling and wound repair as well as in pathological processes such as the irreversible destruction of joints observed in rheumatoid arthritis (RA)2. In addition. MMP catalyze the cleavage of the transmembrane form of tumor necrosis factor (TNF)3,4. Since cells of the monocyte lineage are major producers of TNF in the rheumatoid synovium we analysed the expression of MMP genes in these cells. To examine the transcriptional activity of MMP genes in undifferentiated monocytic cell lines (MonoMac6, U937) and in nature human monocytes isolated from peripheral blood, we developed an assay that is based on reverse transcription (RT) followed by a polymerase chain reaction (PCR). This screening procedure demonstrates that several MMP genes are transcriptionally active in the cells tested after exposure to a variety of stimuli such as phorbol ester, lipopolysaccharide (LPS) and staphylococcal enterotoxin B (SEB). The data were confirmed by quantitative Northern blot analysis. In conclusion, cells of the monocyte lineage produce high mRNA levels of at least six members of the MMP gene family that could participate in joint destruction by resorption of the ECM and secretion of TNF.

Activation of the innate immune system is a prerequisite for the induction of adaptive immunity to infectious and non-infectious agents. Signaling through TLRs, crucial components of the innate immune system that recognize conserved microbial ligands, takes place mainly through MyD88 and lead to the activation of NF-κB and induction of inflammatory responses. Previously, we demonstrated that MyD88-deficient mice are extremely susceptible to infection by Salmonella typhimurium, succumbing to infection with doses 10,000-fold lower than the LD50 in wild-type counterparts. Curiously, despite their heightened susceptibilities, infected MyD88-/- mice produce elevated serum levels of anti-salmonella antibodies, not only of expected Th1-driven antibody isotypes (IgG2c and IgG3) but also of Th2-associated IgG2b and IgG1 isotypes, suggesting a dysregulation in antibody production. Interestingly, this phenotype was not observed in mice infected with other Gram-negative bacteria, including E. coli and Acinetobacter baumanii. In order to further test this hypothesis, sera from infected mice were tested for reactivity to self antigens by determining titers of anti dsDNA antibodies, thyroglobulin, RF and extent of reactivity to Hep2 cells. Our data revealed the existence of high levels of these autoantibodies in Salmonella-infected but not in normal MyD88-/- mice. These findings suggest that TLR-MyD88 signaling pathway may be critical for maintaining self tolerance in B lymphocytes.

Increases in atmospheric temperature are a global phenomenon, but reports of regional climate changes are scarce. Since no long-term air temperature and humidity data were reported from the UAE we obtained routinely collected weather data from three airports in the Emirates. Over the period 1982-2009 in Abu Dhabi, Dubai, and Al Ain the mean annual temperature increased by up to +3°C. Increases were not linear but showed a distinct warming anomaly in 1998 perhaps reflecting naturally occurring climate dynamics as well as local anthropogenic forcing. Over the same period of time, relative humidity decreased suggesting further desertification.

Numerous studies have reported on structural vascular anomalies and ischemia associated with neurofibromatosis type 1 that are thought to stem from dysfunction of neurofibromin, the neurofibromatosis type 1 protein. Documented cases of associated antiphospholipid syndrome fulfilling the accepted diagnostic criteria are exceptionally rare, with only three cases reported in the literature. Here, we report on a patient with neurofibromatosis type 1 and a history of spontaneous abortions presenting with sudden vision loss in the right eye and swelling of the optic nerve head. Fluorescein angiography indicated anterior ischemic optic neuropathy. Brain magnetic resonance imaging revealed findings consistent with left cavernous sinus meningioma. Serologic testing demonstrated persistently elevated anti-b2-glycoprotein antibodies. Her findings suggested antiphospholipid syndrome with concomitant clinical and laboratory evidence of antiphospholipid syndrome: frequent abortions, a vaso-occlusive episode, and persistently elevated antiphospholipid syndrome antibodies. To our knowledge, this case represents the first neuro-ophthalmic manifestation of antiphospholipid syndrome associated with neurofibromatosis type 1.

The protein encoded by the protooncogene c-jun, included in the activator protein-1 (AP-1) complex, is probably the critical trans-acting factor controlling transcription of the procollagenase gene which is rate limiting for subsequent synthesis of procollagenase. Therefore, to elucidate possible mechanisms whereby IL-1 stimulates procollagenase synthesis, we measured levels of c-jun and procollagenase mRNA in human serum-starved dermal fibroblasts in response to human recombinant IL-1 beta (hrIL-1 beta). hrIL-1 beta or serum induced rapid increases in c-jun mRNA levels; mRNA levels declined rapidly after hrIL-1 beta and more slowly after exposure to serum. The increases in levels of c-jun mRNA preceded the increases in procollagenase mRNA. Whereas the increases in levels of procollagenase mRNA were blunted by cycloheximide, those of c-jun mRNA were enhanced. We interpret these results as follows: IL-1 or serum induce transcription of c-jun by mechanisms independent of new protein synthesis; c-JUN, the protein product of c-jun in the AP-1 complex, is an essential mediator of the effects of IL-1 or serum in the subsequent induction of expression of the procollagenase gene.

The aim of the present study was to test simple reaction sequences which describe calcium-independent plus calcium-dependent phosphorylation of sarcoplasmic reticulum transport. ATPase by orthophosphate including the function of magnesium in phosphoenzyme formation. The reaction schemes considered were based on the reaction sequence for calcium-independent phosphorylation proposed previously; namely that the transport enzyme (E) forms a ternary complex (Mg . E . Pi), by random binding of free magnesium and free orthophosphate, which is in equilibrium with the magnesium-phosphoenzyme (Mg . E-P). Phosphorylation, performed at pH 7.0 20 degrees C and a constant free orthophosphate concentration using sarcoplasmic reticulum vesicles either unloaded or loaded passively with calcium in the presence of 5 mM or 40 mM CaCl2, resulted in a gradual decrease in the apparent magnesium half-saturation constant and an increase in maximum phosphoprotein formation with increasing calcium loads. When phosphorylation of sarcoplasmic reticulum vesicles preloaded in the presence of 5 mM CaCl2 was performed at a constant free magnesium concentration, a decrease in the apparent orthophosphate half-saturation constant and an increase in maximum phosphoprotein formation was observed as compared with vesicles from which calcium inside has been removed by ionophore X-537A plus EGTA treatment; however, both parameters remained unchanged by increasing free magnesium from 20 mM to 30 mM. When phosphorylation of sarcoplasmic reticulum vesicles passively loaded with calcium in the presence of 40 mM CaCl2, at which the saturation of the low-affinity calcium binding sites of the ATPase is presumably near maximum, was performed at increasing concentrations of free orthophosphate, there was a parallel shift of phosphoprotein formation as a function of free magnesium and vice versa, with no change in the maximum phosphoenzyme formation. Comparison of the experimental data with the pattern of phosphoprotein formation predicted from model equations for various theoretical possible reaction sequences suggests that phosphoenzyme formation from orthophosphate possesses the following features. Firstly, calcium present at the inside of the sarcoplasmic reticulum membrane binds to the free enzyme and in sequential order to E . Mg . Pi or Mg . E-P or to both, but neither to E. Mg nor to E . Pi. Secondly, calcium-independent and calcium-dependent phosphoproteins are magnesium-phosphoenzymes. Calcium-dependent phosphoenzyme is a magnesium-calcium-enzyme phosphate complex with 1 magnesium, 2 calciums and 1 orthophosphate (the last covalently) bound to the enzyme [Mg . E-P . (Cai)2], and not a 'calcium-phosphoprotein' without bound magnesium.

Lipid metabolic disorder is a critical risk factor for metabolic syndrome, triggering debilitating diseases like obesity and diabetes. Both obesity and diabetes are the epicenter of important medical issues, representing a major international public health threat. Accumulation of fat in adipose tissue, muscles and liver and/or the defects in their ability to metabolize fatty acids, results in insulin resistance. This triggers an early pathogenesis of type 2 diabetes (T2D). In mammals, lipid metabolism involves several organs, including the brain, adipose tissue, muscles, liver, and gut. These organs are part of complex homeostatic system and communicate through hormones, neurons and metabolites. Our study dissects the importance of mammalian Krüppel-like factors in over all energy homeostasis. Factors controlling energy metabolism are conserved between mammals and Caenorhabditis elegans providing a new and powerful strategy to delineate the molecular pathways that lead to metabolic disorder. The C. elegans intestine is our model system where genetics, molecular biology, and cell biology are used to identify and understand genes required in fat metabolism. Thus far, we have found an important role of C. elegans KLF in FA biosynthesis, mitochondrial proliferation, lipid secretion, and β-oxidation. The mechanism by which KLF controls these events in lipid metabolism is unknown. We have recently observed that C. elegans KLF-3 selectively acts on insulin components to regulate insulin pathway activity. There are many factors that control energy homeostasis and defects in this control system are implicated in the pathogenesis of human obesity and diabetes. In this review we are discussing a role of KLF in human metabolic regulation.