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1.
Ann Clin Biochem ; : 45632241239805, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38428927

ABSTRACT

Background: Robust preanalytical and analytical processes are critical for the detection of cryoproteins. There is significant variation in practice in the detection, analysis and reporting. Results: A survey in 2018 of 137 laboratories participating in the UK National External Quality Assessment Service (UK NEQAS) (6) quality control program showed significant variation in the laboratory processes which highlighted the need for standardisation of the detection, analysis and reporting of cryoglobulins.Conclusion: The first available EQA scheme aiming to harmonise practice for cryoprotein testing has been developed by UK NEQAS and laboratories should participate in an appropriate EQA scheme to fulfil requirements for ISO accreditation.

2.
Br J Haematol ; 204(2): 476-486, 2024 02.
Article in English | MEDLINE | ID: mdl-38168756

ABSTRACT

Treatment advances have greatly improved survival, but myeloma is among the worst of all cancers for delayed diagnosis, causing serious morbidities and early deaths. This delay is largely because the symptom profile of myeloma has very low specificity, and in primary care, myeloma is rare. However, initiating the journey to diagnosis simply requires considering myeloma and sending blood to test for monoclonal immunoglobulin. Laboratory tests reliably detect monoclonal immunoglobulin, which is present in 99% of myeloma cases, so why do health care systems have such a problem with delayed diagnosis? The Myeloma UK early diagnosis programme has brought together diverse expertise to investigate this problem, and this article was prepared by the programme's working group for laboratory best practice. It reviews evidence for test requesting, analysis and reporting, for which there is large variation in practice across the United Kingdom. It presents a 'GP Myeloma diagnostic tool' and how it can be integrated into laboratory practice alongside a laboratory best practice tool. It proposes improved requesting and integration with haematology services for reporting and interpretation. Here the laboratory has a central role in creating efficient and cost-effective pathways for appropriate and timely bone marrow examination for myeloma diagnosis.


Subject(s)
Hematology , Multiple Myeloma , Humans , Multiple Myeloma/therapy , Early Detection of Cancer , United Kingdom , Primary Health Care
3.
Dev Policy Rev ; 40(5): e12613, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36246579

ABSTRACT

Motivation: Social assistance, humanitarian relief, and disaster response increasingly overlap, especially where recurrent crises and persistent conflicts prevail. In such situations, distinctions between risk and uncertainty become especially important. It is critical for policy and practice to shift from focusing on risk assessment and management to embracing uncertainty. Purpose: The article assesses the appropriateness of two approaches to social assistance and humanitarian relief where crises recur and conflicts persist: risk assessment and management; and embracing uncertainty and ignorance. Methods and approach: The article reviews different approaches to social assistance, humanitarian relief, and disaster response, and asks how they are framed. It draws on experiences from programmes offering social assistance, humanitarian relief, and disaster response, highlighting the professional, bureaucratic, and institutional features that influence programme design and functioning. These are compared with "high-reliability" approaches deployed in other critical infrastructure-such as water and energy supply. Findings: Mainstream approaches focus on risk assessment and management, assuming predictability and stability. This is problematic, especially in settings of crisis and conflict where there may be no functioning delivery system for social assistance and relief. The article highlights alternatives to the mainstream risk-focused approaches, which emphasize learning, collaboration, adaptation, and flexibility. Such approaches must build on embedded practices of moral economy, collective action, and mutual care and be supported through professional and institutional capacities that generate reliability. Policy implications: The article suggests a new agenda for the intersection of social assistance, humanitarian relief, and disaster response, which makes uncertainty the focus for rethinking responses at scale, especially in settings affected by crisis and conflict.

4.
Clin Exp Rheumatol ; 40(2): 298-303, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35200125

ABSTRACT

OBJECTIVES: To estimate the incidence of anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) antibodies utilising different testing criteria, and review the clinical details of a series of patients with associated autoimmune myopathy. METHODS: The incidence of anti-HMGCR antibodies in 2019 from 3 groups, South West London, Berkshire/Surrey and Southampton, were compared in the adult population. Anti-HMGCR antibodies were measured by commercial chemiluminescent and immunodot assays. The case notes of patients with anti-HMGCR antibodies were reviewed for the case series. RESULTS: The estimated incidence of anti-HMGCR antibodies in the first 2 groups was 1.94 per million adults per year, and in the third group 10.3 per million adults per year. In the first 2 groups the test criteria restricted analysis to specific clinician request for anti-HMGCR. In the third group test criteria included cases with less specific clinical features or a cytoplasmic indirect immunofluorescence anti-nuclear antibody pattern. The latter strategy had a positive predictive value of 66.1% for anti-HMGCR associated myopathy. A case series of 27 patients with anti-HMGCR antibodies revealed 19 with myopathy, oesophageal involvement in 26% and median peak CK 8000 IU/L. Response to treatment, including intravenous immunoglobulin, was good with CK normalising after median 5.5 months. In 8 cases there was no evidence of autoimmune muscle disease, 7 not statin exposed. CONCLUSIONS: Varying criteria result in a 5-fold difference in estimated incidence of anti-HMGCR antibodies, revealing positive cases without evidence of myopathy. Patients with anti-HMGCR myopathy respond well to immune suppression, supporting wider testing for these antibodies amongst patients with myopathy.


Subject(s)
Autoimmune Diseases , Hydroxymethylglutaryl CoA Reductases , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Muscular Diseases , Myositis , Adult , Autoantibodies , Autoimmune Diseases/complications , Autoimmune Diseases/diagnosis , Autoimmune Diseases/epidemiology , Coenzyme A/therapeutic use , Humans , Hydroxymethylglutaryl CoA Reductases/immunology , Hydroxymethylglutaryl CoA Reductases/therapeutic use , Incidence , Muscle, Skeletal , Oxidoreductases/therapeutic use
5.
Ann Clin Biochem ; 59(2): 144-148, 2022 03.
Article in English | MEDLINE | ID: mdl-34937410

ABSTRACT

Multiple myeloma is a haematological cancer caused by malignant plasma cells in the bone marrow that can result in organ dysfunction and death. Recent novel treatments have contributed to improved survival rates, including monoclonal antibody therapies that target the CD38 protein on the surface of plasma cells. Anti-CD38 therapies are IgG kappa monoclonal antibodies that are given in doses high enough for the drug to be visible on serum protein electrophoresis as a small paraprotein. We present a case where isatuximab, the most recent anti-CD38 monoclonal antibody to be approved for treatment of myeloma, obscured the patient's paraprotein on gel immunofixation, so that complete remission could not be demonstrated. This was resolved using the isatuximab Hydrashift assay. The interference on gel immunofixation was unexpected because isatuximab migrated in a position distinct from the patient's paraprotein on capillary zone electrophoresis. We demonstrate the surprising finding that isatuximab migrates in a different position on gel electrophoresis compared to capillary zone electrophoresis. It is vital that laboratories are aware of the possible interference on electrophoresis from anti-CD38 monoclonal antibody therapies, and are able to recognise these drugs on protein electrophoresis. The difference in isatuximab's electrophoretic mobility on capillary and gel protein electrophoresis makes this particularly challenging. Laboratories should have a strategy for alternative analyses in the event that the drugs interfere with assessment of the patient's paraprotein.


Subject(s)
Multiple Myeloma , Antibodies, Monoclonal, Humanized/therapeutic use , Electrophoresis , Humans , Paraproteins
6.
Addict Sci Clin Pract ; 16(1): 22, 2021 03 29.
Article in English | MEDLINE | ID: mdl-33781326

ABSTRACT

BACKGROUND: Knowledge of medical conditions and their evidence-based medications varies among individuals. This range of knowledge may affect attitudes and influence medical decision-making of both patients and providers. Perceptions may be even more impactful in pregnancy, a timeframe subject to bias, and in diseases that include behavioral symptoms and often carry significant societal stigma, such as opioid use disorder (OUD). We present our findings from a survey assessing participants' knowledge of three distinct medical conditions (diabetes mellitus, bipolar disorder, and OUD) and how this knowledge affects perceptions of these disease states during pregnancy. METHODS: Using existing surveys in the literature as a guideline, we designed a cross-sectional survey including multiple-choice questions to evaluate our hypothesis that less knowledge about a medical condition would result in more negative opinions towards that condition and its treatment throughout pregnancy. Participants responded to perception statements using a 5-point Likert scale (1 = "strongly disagree," 5 = "strongly agree"). Surveys were administered to patients in prenatal care, patients in OUD treatment, medical students, and medical residents within a single institution. Response means were generated and compared using t tests and ANOVA. RESULTS: A total of 323 participants completed the survey. There were differences in knowledge between respondent groups and by disease state, with prenatal patients having the least knowledge of all groups about OUD diagnosis (88.5% of prenatal patients answered correctly) and its treatment (91.8% answered correctly). Overall Likert means of all responses demonstrated that participants agreed that new mothers with OUD (mean 4.27, 5 = "strongly agree") and their babies (4.12) would have challenges that others would not, compared to mothers with bipolar disorder (4.03) and their babies (3.60) as well as mothers with diabetes (3.87) and their babies (3.47), p < .001. Overall, respondents were likely to agree that women with OUD should not try to get pregnant (3.47), whereas they overall disagreed with that statement when it pertained to women with bipolar disorder (2.69, 2 = "disagree") or diabetes (2.12), p = 0.03. CONCLUSIONS: With this single-center study, we found that, though there were gaps in knowledge regarding disease and disease treatment during pregnancy, less knowledge was not associated with more negative perceptions of disease and disease treatment during pregnancy. Perceptions were especially negative toward pregnant women with OUD. Increasing awareness of lived experiences of patients with disease, as well as the biases carried by both patients and providers, could improve treatment of chronic diseases and outcomes for patients.


Subject(s)
Opioid-Related Disorders , Attitude , Cross-Sectional Studies , Female , Humans , Pregnancy , Prenatal Care , Social Stigma
7.
Pastoralism ; 10(1): 24, 2020.
Article in English | MEDLINE | ID: mdl-33224462

ABSTRACT

Over the past two decades, the rangelands of Eastern Africa have experienced sweeping changes associated with growing human populations, shifting land use, expanding livestock marketing and trade, and greater investment by domestic and global capital. These trends have coincided with several large shocks that were turning points for how rangeland inhabitants make a living. As livelihoods in the region's rangelands transform in seemingly paradoxical directions, away from customary pastoralist production systems, greater insight is required of how these transformations might affect poverty and vulnerability. This article reviews the state of what is known regarding directions of livelihood change in the rangelands of Eastern Africa, drawing on case studies of structural change in five settings in the region. It considers the implications of long-term change, as well as the emergence of very different livelihood mixes in pastoral rangelands, for efforts to reduce poverty and vulnerability in these places.

8.
PLoS One ; 15(9): e0239294, 2020.
Article in English | MEDLINE | ID: mdl-32941502

ABSTRACT

BACKGROUND AND HYPOTHESIS: The role of smoking as a risk factor for group B streptococcal (GBS) colonization in women during pregnancy has not been previously adequately explored. We hypothesized that women of term or near term neonates who smoked during pregnancy were more likely to have GBS colonization than their non-smoking counterparts. METHODS: The electronic health records (EHRs) of a convenience sample of women delivering in an inner-city university tertiary care center were reviewed. The outcome variable of interest was maternal GBS colonization during pregnancy. The primary independent variable of interest was tobacco smoking during pregnancy, determined from the EHRs by the number of cigarettes smoked during gestation. Descriptive statistics were conducted and categorical data were compared by the Fischer's exact test. Multiple logistic regression analysis was further conducted to determine the independent impact of tobacco smoke exposure on GBS colonization. RESULTS: The prevalence of maternal GBS colonization was 35% among the study population. In the univariate analyses, factors associated with maternal GBS colonization were tobacco smoking during pregnancy (P of trend <0.001), Race (P<0.001), maternal age <20 years (P = 0.006), low birthweight <2500 gm (P = 0.020), maternal drug use (P = 004), and gestational age <37 (P = 0.041). In a multiple logistic regression analysis, tobacco smoking during pregnancy remained the most significant predictor of GBS colonization. Women who smoked during pregnancy were more than twice more likely to be colonized than their non-smoking counterparts (OR = 2.6; 95% CI = 1.5-4.6; p<0.001). Maternal age was the only other significant predictor with younger mothers more than one and a half time more likely to be colonized than their older counterparts (OR = 1.65; 95% CI = 1.02-2.68; P = 0.04). CONCLUSION: The prevalence of GBS colonization in this institution was consistent with recent national rates. Smoking and maternal age were identified as two independent risk factors for GBS colonization during pregnancy. Further studies are needed to confirm these findings.


Subject(s)
Pregnancy Complications/epidemiology , Smoking/epidemiology , Streptococcal Infections/epidemiology , Adult , Female , Humans , Infant, Newborn , Infant, Premature , Male , Pregnancy , Prevalence , Tertiary Care Centers/statistics & numerical data , Virginia
10.
Ann Clin Biochem ; 55(2): 299-301, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28490184

ABSTRACT

Background Daratumumab (Darzalex) is a human IgG1 kappa monoclonal antibody targeting CD38 that has been recently approved for the treatment of refractory multiple myeloma. As it is a monoclonal protein, it can be detected on routine serum protein electrophoresis and by immunofixation. Methods Serum samples from four patients were analysed by serum protein electrophoresis immediately pre- and post-treatment with daratumumab. Results For all four patients, daratumumab was visible on serum protein electrophoresis as an additional small band (approximately 1 g/L) in the slow gamma region. Conclusion Diagnostic laboratories should be aware that daratumumab can be detected on routine serum protein electrophoresis of myeloma patients and should liaise closely with clinicians to ensure the presence of daratumumab is not misinterpreted as development of a new monoclonal protein.


Subject(s)
Antibodies, Monoclonal/blood , Antineoplastic Agents/blood , Electrophoresis, Capillary/methods , Multiple Myeloma/drug therapy , Adult , Aged , Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Blood Proteins/metabolism , Clinical Laboratory Techniques , Humans , Middle Aged , Multiple Myeloma/blood
11.
Ann Clin Biochem ; 55(5): 608-611, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29153027

ABSTRACT

Background Some iodinated radio-contrast media absorb ultraviolet light and can therefore be detected by capillary zone electrophoresis. If seen, these peaks are typically small with 'quantifications' of below 5 g/L. Here, we describe the detection of a large peak on capillary zone electrophoresis that was due to the radio-contrast agent, Omnipaque™. Methods Serum from a patient was analysed by capillary zone electrophoresis, and the IgG, IgA, IgM and total protein concentrations were measured. The serum sample was further analysed by gel electrophoresis and immunofixation. Results Capillary zone electrophoresis results for the serum sample showed a large peak with a concentration high enough to warrant urgent investigation. However, careful interpretation alongside the serum immunoglobulin concentrations and total protein concentration showed that the abnormal peak was a pseudoparaprotein rather than a monoclonal immunoglobulin. This was confirmed by analysis with gel electrophoresis and also serum immunofixation. The patient had had a CT angiogram with the radio-contrast agent Omnipaque™; addition of Omnipaque™ to a normal serum sample gave a peak with comparable mobility to the pseudoparaprotein in the patient's serum. Conclusions Pseudoparaproteins can appear as a large band on capillary zone electrophoresis. This case highlights the importance of a laboratory process that detects significant electrophoretic abnormalities promptly and interprets them in the context of the immunoglobulin concentrations. This should avoid incorrect reporting of pseudoparaproteins which could result in the patient having unnecessary investigations.


Subject(s)
Contrast Media , Electrophoresis, Capillary/methods , Electrophoresis, Capillary/standards , Immunoglobulins/blood , Artifacts , Contrast Media/classification , Data Accuracy , Humans , Immunoglobulins/classification , Paraproteins/chemistry
12.
Clin Anat ; 28(8): 1048-57, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26385008

ABSTRACT

Research on the relationship between body mass index (BMI) and cross-sectional geometry of long bone diaphyses demonstrates that strength properties are significantly greater in obese versus normal BMI individuals. However, articular dimensions do not differ appreciably. If femoral head size remains constant, we hypothesize that the femoral neck remodels to accommodate greater loads associated with increased BMI. High-resolution CT scans (n = 170 males) were divided into three BMI groups (normal, overweight, and obese) and two age groups (21-50 and >50). OsiriX software was used to obtain a cross-sectional slice at the waist of the femoral neck. Cortical area (CA), total cross-sectional area (TA), percent cortical area (%CA), circularity index (Imax /Imin ), section modulus (Zpol ), and second moment of area (J) were measured with ImageJ software. The effects of age and BMI were evaluated statistically. Pairwise comparisons in the younger group only detected significant differences between normal and obese males in the circularity index (P = 0.022). The older cohort showed significant differences in CA (P < 0.001), %CA (P = 0.004), Zpol (P = 0.007), and J (P < 0.001) between normal and obese groups. This study shows that the effects of obesity on the cross-sectional geometry of the femoral neck are more pronounced in older males relative to younger males. Older males with increased BMI have greater cortical area and bone strength in the femoral neck relative to younger males, thus making the femoral neck less susceptible to fractures in obese individuals.


Subject(s)
Aging/physiology , Body Mass Index , Femur Neck/anatomy & histology , Obesity/pathology , Adaptation, Physiological , Adult , Age Factors , Aged , Aged, 80 and over , Bone Remodeling , Femur Neck/diagnostic imaging , Femur Neck/pathology , Humans , Ideal Body Weight , Male , Middle Aged , Tomography, X-Ray Computed , Young Adult
13.
J Med Genet ; 47(9): 595-600, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20798128

ABSTRACT

BACKGROUND: Familial haemophagocytic lymphohistiocytosis (FHL) is a rare immune deficiency with uncontrolled inflammation; the clinical course usually starts within the first years of life, and is usually fatal unless promptly treated and then cured with haematopoietic stem cell transplant. FHL is caused by genetic mutations resulting in defective cell cytotoxicity; three disease related genes have been identified to date: perforin, Munc13-4 and syntaxin-11. A fourth gene, STXBP2, has been identified very recently as responsible for a defect in Munc18-2 in FHL-5. AIMS: To describe the result of the screening of families with HLH and previously unassigned genetic defects. METHODS: Patients with HLH diagnosed according to current diagnostic criteria, and who lacked mutations in the PRF1, Munc13-4, and STX11 genes were sequenced for mutations in STXBP2. Functional study was performed when material was available. RESULTS: Among the 28 families investigated, 4 (14%) with biallelic STXBP2 mutations were identified. They originated from Italy, England, Kuwait and Pakistan. The p.Pro477Leu resulting from c.1430C>T, and p.Arg405Gln resulting from the single c.1214G>A nucleotide change are known, while we contribute two novel mutations: p.Glu132Ala resulting from c.395A>C, and p.Gly541Ser, resulting from c.1621G>A. The detrimental effect of the p.Gly541Ser mutation was documented biochemically and functionally in NK and CD8 cells. Additional polymorphisms are also described. CONCLUSION: These data expand current knowledge on the genetic heterogeneity of FHL and suggest that patients with FHL5 may have different results in degranulation assays under different conditions.


Subject(s)
Lymphohistiocytosis, Hemophagocytic/classification , Lymphohistiocytosis, Hemophagocytic/genetics , Munc18 Proteins/genetics , Mutation/genetics , Alleles , Cell Degranulation , Child , Child, Preschool , Cytotoxicity, Immunologic , Female , Flow Cytometry , Humans , Immunoprecipitation , Infant , Lymphohistiocytosis, Hemophagocytic/immunology , Lysosomal-Associated Membrane Protein 1/metabolism , Male , T-Lymphocytes, Cytotoxic/physiology
15.
J Immunol ; 185(4): 2458-66, 2010 Aug 15.
Article in English | MEDLINE | ID: mdl-20644165

ABSTRACT

Inflammatory responses are essential for immune protection but may also cause pathology and must be regulated. Both Th1 and Th17 cells are implicated in the pathogenesis of autoimmune inflammatory diseases, such as multiple sclerosis. We show in this study that IL-18-binding protein (IL-18bp), the endogenous inhibitor of the Th1-promoting cytokine IL-18, is upregulated by IFN-gamma in resident microglial cells in the CNS during multiple sclerosis-like disease in mice. Test of function by overexpression of IL-18bp in the CNS using a viral vector led to marked reduction in Th17 responses and robust inhibition of incidence, severity, and histopathology of disease, independently of IFN-gamma. The disease-limiting action of IL-18bp included suppression of APC-derived Th17-polarizing cytokines. IL-18bp thus acts as a sensor for IFN-gamma and can regulate both Th1 and Th17 responses in the CNS.


Subject(s)
Central Nervous System/immunology , Inflammation/immunology , Intercellular Signaling Peptides and Proteins/immunology , Interferon-gamma/immunology , T-Lymphocytes, Helper-Inducer/immunology , Animals , Cell Line , Central Nervous System/drug effects , Central Nervous System/pathology , Encephalomyelitis, Autoimmune, Experimental/genetics , Encephalomyelitis, Autoimmune, Experimental/immunology , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Female , Flow Cytometry , Humans , Inflammation/genetics , Inflammation/prevention & control , Injections, Spinal , Intercellular Signaling Peptides and Proteins/administration & dosage , Intercellular Signaling Peptides and Proteins/genetics , Interferon-gamma/genetics , Interleukin-17/immunology , Interleukin-17/metabolism , Interleukin-18/genetics , Interleukin-18/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Reverse Transcriptase Polymerase Chain Reaction , T-Lymphocytes, Helper-Inducer/metabolism
16.
Immunology ; 118(4): 527-38, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16780563

ABSTRACT

Inflammation in the central nervous system (CNS) can be studied in experimental autoimmune encephalomyelitis (EAE). The proinflammatory cytokines interferon-gamma (IFN-gamma) and tumour necrosis factor (TNF) are implicated in EAE pathogenesis. Signals through the type 1 TNF receptor (TNFR1) are required for severe EAE to develop, whereas deficiency in IFN-gamma or its receptor result in more severe EAE. We investigated IFN-gamma expression in TNFR1-deficient (TNFR1-/-) mice. We describe here that there were more IFN-gamma-secreting T cells present in the CNS of TNFR1-/- mice during EAE compared to wild-type (WT) mice, despite that clinical symptoms were mild, with delayed onset. There was greater expression of IL-12/23p40 by antigen-presenting cells in these mice, and in vitro, TNFR1-/- antigen-presenting cells induced greater secretion of IFN-gamma but not interleukin (IL)-17 when cultured with primed T cells than did WT antigen presenting cells. TNFR1-/- mice with EAE had significantly higher expression of CXCL10 mRNA (but not CCL5 mRNA) in the CNS compared to WT mice with EAE. These data demonstrate that IFN-gamma expression is enhanced in the CNS of TNFR1-/- mice with EAE and suggest that IFN-gamma levels do not necessarily correlate with EAE severity.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental/immunology , Gene Expression Regulation , Interferon-gamma/genetics , Macrophages/immunology , Receptors, Tumor Necrosis Factor, Type I/genetics , T-Lymphocytes/immunology , Animals , Encephalomyelitis, Autoimmune, Experimental/genetics , Encephalomyelitis, Autoimmune, Experimental/microbiology , Interferon-gamma/analysis , Mice , Mice, Inbred C57BL , Mice, Knockout , Receptors, Tumor Necrosis Factor, Type I/analysis , Reverse Transcriptase Polymerase Chain Reaction , Spinal Cord/immunology
17.
J Neuroimmunol ; 145(1-2): 40-5, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14644029

ABSTRACT

Interleukin (IL)-18, a member of the IL-1 family, is a key mediator of peripheral inflammation and host defense responses, and has been implicated in inflammatory and neurodegenerative diseases in the brain. IL-18 acts via a receptor complex that closely resembles that of IL-1, consisting of a ligand binding protein, IL-18Ralpha, and an accessory protein, IL-18Rbeta. Here, we describe the presence of a splice variant of IL-18Rbeta that is predicted to encode a truncated soluble protein, consisting of only the first immunoglobulin-like domain of IL-18Rbeta (EMBL/Genbank accession number AJ550893). Both forms of IL-18Rbeta were expressed in rat cortex, striatum, hypothalamus, hippocampus, and also liver, and were detected in pure cultures of microglia, astrocytes and neurons. This novel splice variant is up-regulated rapidly in microglial cells by bacterial lipopolyssacharide (LPS). We propose that this putative truncated form of IL-18Rbeta is analogous to the soluble form of IL-1R accessory protein, and could act as an important regulator of IL-18 actions.


Subject(s)
Brain/immunology , Brain/metabolism , Interleukin-18/metabolism , RNA, Messenger/biosynthesis , Receptors, Interleukin/physiology , Sequence Deletion , Alternative Splicing/immunology , Amino Acid Sequence , Animals , Astrocytes/immunology , Astrocytes/metabolism , Base Sequence , Brain/cytology , Cells, Cultured , Interleukin-18/biosynthesis , Interleukin-18 Receptor beta Subunit , Male , Mice , Microglia/immunology , Microglia/metabolism , Molecular Sequence Data , Rats , Rats, Sprague-Dawley , Receptors, Interleukin/genetics , Receptors, Interleukin/isolation & purification , Solubility
18.
J Neurochem ; 85(6): 1412-20, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12787061

ABSTRACT

Interleukin (IL)-18, a member of the IL-1 cytokine family, is an important mediator of peripheral inflammation and host defence responses. IL-1 is a key proinflammatory cytokine in the brain, but the role of IL-18 in the CNS is not yet clear. The objective of this study was to investigate the actions of IL-18 on mouse glial cells. IL-18 induced intracellular expression of IL-1 alpha and proIL-1 beta, and release of IL-6 from mixed glia. Treatment of lipopolysaccharide-primed microglia with adenosine triphosphate (ATP), an endogenous secondary stimulus, induced IL-1 beta and IL-18 release. Although deletion of the IL-18 gene did not affect IL-1 beta expression or release in this experimental paradigm, IL-1 beta knockout microglia released significantly less IL-18 compared to wild-type microglia. In addition, ATP induced release of mature IL-1 beta from IL-18-primed microglia. These data suggest that IL-18 may contribute to inflammatory responses in the brain, and demonstrate that, in spite of several common features, IL-18 and IL-1 beta differ in their regulation and actions.


Subject(s)
Cytokines/metabolism , Interleukin-18/pharmacology , Interleukin-1/pharmacology , Neuroglia/drug effects , Neuroglia/metabolism , Adenosine Triphosphate/pharmacology , Animals , Cells, Cultured , Drug Interactions , Gene Expression/drug effects , Interleukin-1/genetics , Interleukin-1/metabolism , Interleukin-18/genetics , Interleukin-18/metabolism , Interleukin-18 Receptor alpha Subunit , Lipopolysaccharides/pharmacology , Mice , Mice, Inbred C57BL , Mice, Knockout , Microglia/drug effects , Microglia/metabolism , Receptors, Interleukin/biosynthesis , Receptors, Interleukin-18
19.
Cytokine ; 21(4): 161-6, 2003 Feb 21.
Article in English | MEDLINE | ID: mdl-12788303

ABSTRACT

Interleukin (IL)-18 is a pro-inflammatory cytokine that plays a critical role in inflammation leading to liver damage, through promotion of Fas-mediated apoptosis. Inhibition of IL-18 activity protects against LPS-induced lethality in mice and against liver damage induced by LPS after sensitisation of mice with Proprionibacterium acnes. A specific, potent, endogenous inhibitor of IL-18 (IL-18BP) has been identified in mice and humans, and IL-18BP mRNA is expressed constitutively in liver. The objectives of this study were to compare changes in IL-1beta and IL-18 mRNA expression in the liver of rats in response to peripheral injection of LPS, using real-time PCR, and also to investigate whether IL-18BP mRNA expression is affected by this treatment. LPS rapidly up-regulated IL-1beta mRNA expression, but IL-18 mRNA expression was unaffected by LPS treatment. Unlike IL-18, IL-18BP mRNA was up-regulated dramatically by approximately 12-fold above nai;ve levels, peaking 3 h after LPS injection. This ability of LPS to up-regulate expression of the endogenous IL-18 inhibitor may indicate a mechanism by which the inflammatory response to LPS is regulated.


Subject(s)
Glycoproteins/genetics , Interleukin-18/genetics , Lipopolysaccharides/pharmacology , Liver/drug effects , Liver/metabolism , Up-Regulation/drug effects , Animals , Intercellular Signaling Peptides and Proteins , Interleukin-1/genetics , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Time Factors , Tumor Necrosis Factor-alpha/genetics
20.
J Cereb Blood Flow Metab ; 23(5): 531-5, 2003 May.
Article in English | MEDLINE | ID: mdl-12771567

ABSTRACT

There is now extensive evidence to show that the cytokine interleukin-1 (IL-1) contributes directly to reversible and permanent ischemic brain damage in rodents. Because interleukin-18 (IL-18) shares many structural and functional similarities with IL-1, the authors tested the hypothesis that IL-18 contributes directly to ischemic brain damage in mice exposed to focal, reversible (15-minute or 30-minute) middle cerebral artery occlusion. IL-18 expression was not induced acutely by middle cerebral artery occlusion, and deletion of the IL-18 gene (IL-18 knockout mice) did not affect infarct volume. The present results suggest that IL-18 does not contribute to acute ischemic brain damage.


Subject(s)
Brain Ischemia/physiopathology , Infarction, Middle Cerebral Artery/physiopathology , Interleukin-18/genetics , Interleukin-18/metabolism , Acute Disease , Animals , Body Temperature , Body Weight , Brain Ischemia/pathology , Infarction, Middle Cerebral Artery/pathology , Mice , Mice, Inbred C57BL , Mice, Knockout
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