ABSTRACT
Objectives: The Spondyloarthritis Research Consortium of Canada (SPARCC) sacroiliac joint (SIJ) scoring system assesses six or five (6/5) semicoronal magnetic resonance imaging (MRI) slices for inflammation/structural lesions in patients with axial spondyloarthritis (axSpA). However, the cartilaginous SIJ compartment may be visible in a few additional slices. The objective was to investigate interreader reliability, sensitivity to change, and classification of MRI scans as positive or negative for various lesion types using an 'all slices' approach versus standard SPARCC scoring of 6/5 slices.Method: Fifty-three axSpA patients were treated with the tumour necrosis factor inhibitor golimumab and followed with serial MRI scans at weeks 0, 4, 16, and 52. The most anterior and posterior slices covering the cartilaginous compartment and the transitional slice were identified. Scores for inflammation, fat metaplasia, erosion, backfill, and ankylosis in the cartilaginous SIJ compartment were calculated for the 'all slices' approach and the 6/5 slices standard.Results: By the 'all slices' approach, three readers scored mean 7.2, 7.7, and 7.0 slices per MRI scan. Baseline and change scores for the various lesion types closely correlated between the two approaches (Pearson's rho ≥ 0.95). Inflammation score was median 13 (interquartile range 6-21, range 0-49) for 6/5 slices versus 14 (interquartile range 6-23, range 0-69) for all slices at baseline. Interreader reliability, sensitivity to change, and classification of MRI scans as positive or negative for various lesion types were similar.Conclusion: The standardized 6/5 slices approach showed no relevant differences from the 'all slices' approach and, therefore, is equally suited for monitoring purposes.
Subject(s)
Sacroiliac Joint/diagnostic imaging , Sacroiliitis/diagnostic imaging , Spondylarthropathies/diagnostic imaging , Adipose Tissue/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Ankylosis/diagnostic imaging , Antibodies, Monoclonal/therapeutic use , Bone Marrow/diagnostic imaging , Cartilage, Articular/diagnostic imaging , Cortical Bone/diagnostic imaging , Edema/diagnostic imaging , Female , Humans , Inflammation , Magnetic Resonance Imaging/methods , Male , Metaplasia , Middle Aged , Observer Variation , Sacroiliitis/drug therapy , Spondylarthropathies/drug therapy , Tumor Necrosis Factor Inhibitors/therapeutic use , Young AdultABSTRACT
OBJECTIVES: Touch screens for entering patient-reported outcomes (PROs) are available at all Danish departments of rheumatology reporting to the nationwide DANBIO registry. This project comprises two substudies in patients with rheumatoid arthritis (RA) or axial spondyloarthritis (AxSpA), aiming to (A) investigate the feasibility of first line patient recruitment for research via touch screens, and (B) compare PROs collected at hospital versus at home, including patient preferences. METHOD: Substudy A: using a touch screen, patients answered whether we could contact them about a clinical research project (yes/no). Characteristics of patients who accepted/declined were explored using chi-squared and Mann-Whitney U-tests. Substudy B (randomized crossover agreement study): a random sample of patients from the accepting group in substudy A was contacted by telephone. According to prespecified power and sample size estimation, 56 patients were included. After randomization, 50% of patients entered PROs and information on comorbidities and lifestyle from home and then at hospital, and 50% first from hospital and then at home. Finally, they stated their preference for data entry (hospital/home/equally good). Differences in PROs entered from home and in the hospital were compared (limits of agreement, 95% confidence intervals, and intraclass correlation coefficients). RESULTS: The touch-screen invitation was accepted by 428/952 patients (45%). Patients who accepted and those who declined had similar PROs and demographics. Substudy B was completed by 42 patients (22 RA, 20 AxSpA). They had no significant differences between PROs and lifestyle/comorbidity data entered from home and hospital, except for AxSpA patients on the Bath Ankylosing Spondylitis Functional Index and Bath Ankylosing Spondylitis Disease Activity Index item 5. The preferred method of data entry was hospital (10%), home (50%), and equally good (40%). CONCLUSION: Touch screens seem feasible for first line research recruitment. PROs collected from home were similar to the touch-screen solution. Patients preferred data entry from home.
Subject(s)
Arthritis, Rheumatoid , Online Systems/organization & administration , Outcome Assessment, Health Care/methods , Patient Reported Outcome Measures , Patient Selection , Spondylarthritis , Adult , Arthritis, Rheumatoid/epidemiology , Arthritis, Rheumatoid/therapy , Denmark/epidemiology , Feasibility Studies , Female , Hospitalization , Humans , Male , Middle Aged , Outpatients , Patient Preference , Registries , Spondylarthritis/epidemiology , Spondylarthritis/therapyABSTRACT
OBJECTIVE: To investigate temporal changes in structural progression assessed by serial conventional radiography and magnetic resonance imaging (MRI) of the sacroiliac joints (SIJs) and spine in patients with ankylosing spondylitis (AS) treated with tumour necrosis factor (TNF) inhibitor for 5 years. METHOD: Forty-two patients were included and 33 patients were followed for 5 years in a prospective investigator-initiated study. Conventional radiographs were required four times and MRI seven times. The modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS); Spondyloarthritis Research Consortium of Canada (SPARCC) MRI SIJ and Spine Inflammation, and SPARCC MRI SIJ Structural Score (SSS) for Fat, Erosion, Backfill, and Ankylosis; and the Canada-Denmark MRI scores for Spine Inflammation, Fat, Erosion, and New Bone Formation (NBF) were applied. RESULTS: Compared with baseline, MRI Inflammation had decreased significantly at week 22 (spine)/week 46 (SIJ) and thereafter. MRI SIJ Fat (from week 22), SIJ Ankylosis, Spine NBF, and mSASSS had increased significantly at week 46 and thereafter. SIJ Erosion had decreased from year 2. The annual progression rate in mSASSS was significantly higher during weeks 0-46 compared to week 46 to year 3. In multivariate regression analyses, baseline SIJ Inflammation and Backfill were independent predictors of 5 year progression in SIJ Ankylosis. Spine Erosion predicted progression in Spine NBF. Longitudinally, Ankylosing Spondylitis Disease Activity Score, Bath Ankylosing Spondylitis Disease Activity Index, MRI Spine Inflammation, Fat, and Erosion scores were significantly associated with mSASSS. SIJ Inflammation, Fat, Erosion, and Backfill scores were longitudinally associated with SIJ Ankylosis. Structural progression was not associated with body mass index, smoking, or Assessment of SpondyloArthritis international Society Non-Steroidal Anti-Inflammatory Drug Index. CONCLUSION: In a 5 year follow-up study of patients with AS treated with TNF inhibitor, structural progression decreased over time.
Subject(s)
Antirheumatic Agents/therapeutic use , Magnetic Resonance Imaging , Radiography , Sacroiliac Joint , Spondylitis, Ankylosing , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adult , Disease Progression , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/statistics & numerical data , Male , Middle Aged , Outcome Assessment, Health Care , Prospective Studies , Radiography/methods , Radiography/statistics & numerical data , Sacroiliac Joint/diagnostic imaging , Sacroiliac Joint/pathology , Severity of Illness Index , Spondylitis, Ankylosing/diagnosis , Spondylitis, Ankylosing/drug therapy , Spondylitis, Ankylosing/physiopathologyABSTRACT
OBJECTIVES: To investigate the pattern and development of bone erosion and proliferation in patients with psoriatic arthritis (PsA) during treatment with adalimumab, using high-resolution computed tomography (CT) and conventional radiography. METHOD: Forty-one biologic-naïve PsA patients were initiated with adalimumab 40 mg subcutaneously every other week. CT and radiography of the 2nd-5th metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints were conducted at baseline (n = 41) and after 24 weeks (n = 32). Changes in bone erosion and proliferation are described and the imaging modalities compared. RESULTS: Ninety percent of bone erosions detected by CT were located in the metacarpal heads, and most frequently in the 2nd-3rd MCP joints. Radial (37%) and ulnar (31%) surfaces were more frequently eroded than dorsal (10%) and palmar (22%) sites. Using CT, bone proliferations were located primarily on the sides of the distal part of the DIP joints (43% of all proliferations), but also proximally in DIP (17%) and MCP joints (27%). For bone erosions and proliferations, respectively, radiography showed a low sensitivity (17% and 26%), but a high specificity (98% and 95%) and accuracy (93% and 87%), with CT as the gold standard reference. Neither CT nor radiography revealed statistically significant changes in bone erosion or proliferation scores between baseline and follow-up. CONCLUSIONS: Patterns of bone erosion and proliferation in PsA hands were revealed in more detail by CT than by radiography. No overall progression or repair could be detected during adalimumab treatment with either of the methods.
Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Arthritis, Psoriatic/diagnostic imaging , Arthritis, Psoriatic/drug therapy , Metacarpophalangeal Joint/drug effects , Metacarpophalangeal Joint/diagnostic imaging , Tomography, X-Ray Computed/methods , Adalimumab , Adult , Anti-Inflammatory Agents/administration & dosage , Arthritis, Psoriatic/pathology , Bone and Bones/cytology , Bone and Bones/pathology , Cell Proliferation , Cohort Studies , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Injections, Subcutaneous , Longitudinal Studies , Male , Metacarpophalangeal Joint/pathology , Middle Aged , Radiography/methods , Reproducibility of Results , Risk Assessment , Severity of Illness Index , Statistics, Nonparametric , Time Factors , Treatment OutcomeABSTRACT
OBJECTIVE: To evaluate new classification criteria for peripheral spondyloarthritis (SpA) in patients with SpA with peripheral manifestations only. METHODS: In this Assessment of SpondyloArthritis international Society (ASAS) study, two prespecified sets of criteria were compared against the European Spondylarthropathy Study Group (ESSG) and Amor criteria in newly referred consecutive patients with undiagnosed peripheral arthritis, and/or enthesitis, and/or dactylitis that usually began before 45 years of age. The clinical diagnosis (SpA vs no SpA) made by the ASAS rheumatologist served as reference standard. RESULTS: In all, 24 ASAS centres included 266 patients, with a final diagnosis of SpA being made in 66.2%. After adjustments a final set of criteria showed the best balance between sensitivity (77.8%) and specificity (82.9%): arthritis and/or enthesitis and/or dactylitis plus (A) one or more of the following parameters: psoriasis, inflammatory bowel disease, preceding infection, human leucocyte antigen B27, uveitis, sacroiliitis on imaging, or (B) two or more other parameters: arthritis, enthesitis, dactylitis, inflammatory back pain in the past, family history of SpA. The new criteria performed better than modified versions of the ESSG (sensitivity 62.5%, specificity 81.1%) and the Amor criteria (sensitivity 39.8%, specificity 97.8%), particularly regarding sensitivity. In the entire ASAS population of 975 patients the combined use of ASAS criteria for axial SpA and ASAS criteria for peripheral SpA also had a better balance (sensitivity 79.5%, specificity 83.3%) than the modified ESSG (sensitivity 79.1%, specificity 68.8%) and Amor criteria (sensitivity 67.5%, specificity 86.7%), respectively. CONCLUSIONS: The new ASAS classification criteria for peripheral SpA performed well in patients presenting with peripheral arthritis, enthesitis and/or dactylitis.
Subject(s)
Spondylarthritis/classification , Adult , Arthritis, Reactive/classification , Arthritis, Reactive/diagnosis , Diagnosis, Differential , Female , Humans , Inflammatory Bowel Diseases/complications , International Cooperation , Male , Middle Aged , Psoriasis/complications , Sacroiliitis/complications , Sensitivity and Specificity , Spondylarthritis/complications , Spondylarthritis/diagnosis , Spondylitis, Ankylosing/classification , Spondylitis, Ankylosing/complications , Spondylitis, Ankylosing/diagnosis , Uveitis/complications , Young AdultABSTRACT
OBJECTIVE: To validate and refine two sets of candidate criteria for the classification/diagnosis of axial spondyloarthritis (SpA). METHODS: All Assessment of SpondyloArthritis international Society (ASAS) members were invited to include consecutively new patients with chronic (> or =3 months) back pain of unknown origin that began before 45 years of age. The candidate criteria were first tested in the entire cohort of 649 patients from 25 centres, and then refined in a random selection of 40% of cases and thereafter validated in the remaining 60%. RESULTS: Upon diagnostic work-up, axial SpA was diagnosed in 60.2% of the cohort. Of these, 70% did not fulfil modified New York criteria and, therefore, were classified as having "non-radiographic" axial SpA. Refinement of the candidate criteria resulted in new ASAS classification criteria that are defined as: the presence of sacroiliitis by radiography or by magnetic resonance imaging (MRI) plus at least one SpA feature ("imaging arm") or the presence of HLA-B27 plus at least two SpA features ("clinical arm"). The sensitivity and specificity of the entire set of the new criteria were 82.9% and 84.4%, and for the imaging arm alone 66.2% and 97.3%, respectively. The specificity of the new criteria was much better than that of the European Spondylarthropathy Study Group criteria modified for MRI (sensitivity 85.1%, specificity 65.1%) and slightly better than that of the modified Amor criteria (sensitivity 82.9, specificity 77.5%). CONCLUSION: The new ASAS classification criteria for axial SpA can reliably classify patients for clinical studies and may help rheumatologists in clinical practice in diagnosing axial SpA in those with chronic back pain. TRIAL REGISTRATION NUMBER: NCT00328068.
Subject(s)
Algorithms , Sacroiliac Joint/pathology , Spondylarthritis/classification , Spondylitis, Ankylosing/classification , Adult , Diagnosis, Differential , Female , Humans , Magnetic Resonance Imaging , Male , Reproducibility of Results , Spondylarthritis/diagnosis , Spondylitis, Ankylosing/diagnosisABSTRACT
Treatment with tumour necrosis factor-alpha inhibitors increases the risk of tuberculosis (TB). Screening for latent TB infection (LTBI) and prophylactic treatment has become mandatory. A 79-yr-old female with a history of severe erosive sero-positive rheumatoid arthritis was screened for LTBI before initiation of treatment with infliximab. The tuberculin skin test (TST) was negative, chest radiography was normal and she had no known risk factors for TB. After 4 months of treatment with infliximab, the patient developed ascites caused by Mycobacterium bovis. The TST was repeatedly negative. QuantiFERON-TB (QFT) testing performed during screening and immunosuppressive treatment was indeterminate, whereas the QFT test performed at the time of ascites puncture was positive. The patient history revealed previous work at a dairy, with probable exposure to unpasteurised milk from M. bovis-infected cattle. Re-activation of bovine tuberculosis is a risk in people with recent or previous exposure to unpasteurised dairy products. The QuantiFERON-TB test has the potential to detect Mycobacterium bovis infection. Indeterminate test results reflect either anergy, due to poor immunity, or technical problems and should be cautiously interpreted and as a minimum be repeated. Studies are ongoing to determine the role of QuantiFERON-TB testing in the screening for latent tuberculosis infection.
Subject(s)
Antibodies, Monoclonal/adverse effects , Immunocompromised Host , Mycobacterium tuberculosis/immunology , Tuberculosis, Pulmonary/diagnosis , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Aged , Female , Humans , Infliximab , Interferon-gamma/analysis , Mycobacterium tuberculosis/isolation & purification , Pleural Effusion/microbiology , Tuberculin Test , Tuberculosis, Pulmonary/immunology , Tuberculosis, Pulmonary/microbiologyABSTRACT
Serum amyloid P component (SAP), a member of the pentraxin family of proteins, binds calcium-dependently to several ligands including glycosaminoglycans (GAG's). We have investigated the influence of pH on the Ca2(+)-dependent binding of SAP to solid phase GAG's and amyloid fibril proteins (AA and beta2M) by ELISA. An increase in the dose-dependent binding of SAP to heparan sulfate, AA-protein and beta2M was observed as the pH decreased from 8.0 to 5.0. Furthermore, a lower, but significant Ca2(+)-independent binding of SAP to heparan sulfate, dermatan sulfate, AA protein and the amyloid precursor protein beta2M was observed. This binding was also enhanced at slightly acid pH, most pronounced at pH 5.0. The results of this study indicate that SAP can exhibit both Ca2(+)-dependent and -independent binding to ligands involved in amyloid fibril formation and that the binding is enhanced under conditions of slightly lowered pH.
Subject(s)
Amyloid/metabolism , Calcium/metabolism , Glycosaminoglycans/metabolism , Protein Precursors/metabolism , Serum Amyloid P-Component/metabolism , Humans , Hydrogen-Ion Concentration , Up-RegulationABSTRACT
Serum amyloid P component (SAP) is a pentraxin found in the circulation and in all forms of amyloid deposits. Its physiological and pathophysiological functions are largely unknown. Electron microscopy showed purified human SAP to consist of double pentameric discs compatible with the results of size chromatography. The formation of double pentamers did not require calcium ions. The outer diameter of the discs arranged face-to-face was 11.6 nm and the inner diameter 3.2 nm. The thickness of single and double pentamers was 4.1 and 8.7 nm, respectively. Quadruple pentamers were occasionally seen. The self-aggregation of human SAP molecules was investigated in the presence and absence of calcium ions at different concentrations. In calcium-free solutions few and mostly small SAP aggregates were seen. After addition of calcium at increasing concentration the aggregates grew in size and crystalline-like structures were formed already at 2 mM calcium. At 25 mM calcium, large aggregates with a crystalline array occasionally exhibiting cylinders predominated. Binding of the ligands heparin and heparan sulphate to SAP completely abolished the calcium-enhanced aggregation, but the distribution of the SAP molecules was affected, resulting in strands or groups of adjacent molecules. The electrophoretic mobility of SAP was moreover significantly altered after its calcium-dependent reaction with these ligands. We conclude that purified SAP has a tendency to double pentamer formation and self-aggregation also in the absence of calcium ions. However, aggregation is greatly enhanced even at low concentrations (2 mM) of calcium. SAP's tendency to self-aggregation is abolished after its binding to heparin or heparin sulphate. Furthermore, our TEM studies indicate that purified human SAP freed of its natural ligands has the double pentameric form, whereas the electrophoretic investigations suggest that SAP's interaction with low-molecular-weight natural ligands in serum prevents homodimerization and self-aggregation.
Subject(s)
Calcium/pharmacology , Heparin/pharmacology , Heparitin Sulfate/pharmacology , Serum Amyloid P-Component/antagonists & inhibitors , Serum Amyloid P-Component/analysis , Blotting, Western , Dose-Response Relationship, Drug , Edetic Acid/pharmacology , Humans , Immunoelectrophoresis, Two-Dimensional , Microscopy, Electron , Molecular Weight , Serum Amyloid P-Component/ultrastructureABSTRACT
The distributions of sodium and potassium in the serum on admission, and the types of medicine used were studied retrospectively in hospitalized geriatric patients (n = 1418). Sodium concentrations below 130 mmol/l were found in 7.4% and potassium concentrations below 3.0 mmol/l in 5.0% of patients. Risk factors for low sodium concentrations were treatment with the combination of thiazide+amiloride, potassium-sparing diuretics, thiazides, emergency hospitalization and low body weight. Risk factors for low potassium concentrations were treatment with the combination of thiazide+amiloride, thiazides and female gender. On an average, patients were given two different drugs from specified groups both on admission and on discharge, but changes in medical treatment were often performed during the hospital stay. Prehospital treatment with thiazide diuretics and the combination of thiazide+amiloride was frequently withdrawn. 38% were given benzodiazepines on discharge. In 40.4% of these, treatment had been started during the hospital stay, most often on account of insomnia.
Subject(s)
Drug-Related Side Effects and Adverse Reactions , Potassium/blood , Sodium/blood , Aged , Benzodiazepines/adverse effects , Denmark/epidemiology , Diuretics/adverse effects , Female , Hospital Departments/statistics & numerical data , Humans , Hypokalemia/chemically induced , Hypokalemia/epidemiology , Hyponatremia/chemically induced , Hyponatremia/epidemiology , Male , Patient Admission , Retrospective Studies , Risk FactorsABSTRACT
Dengue virus infections have increased globally. This results in an increased incidence of patients with dengue fever in Denmark. In order to draw attention to this diagnosis among febrile persons returning from a stay in tropical and subtropical areas, we present two cases of dengue virus infection and describe the symptoms and diagnostic possibilities. Dengue Haemorrhagic Fever (DHF) is supposed to occur only in persons who have previously had dengue virus infection and who acquire a second infection with dengue virus.
Subject(s)
Dengue , Severe Dengue , Adult , Antibodies, Viral/analysis , Dengue/diagnosis , Dengue/therapy , Dengue/transmission , Diagnosis, Differential , Female , Humans , Immunoglobulin M/analysis , Male , Severe Dengue/diagnosis , Severe Dengue/therapy , Severe Dengue/transmission , Travel , Tropical MedicineABSTRACT
A C4 variant found in about 5% of the population is described. The fast-moving part of this variant is governed by an allele (Fx) codominant to F. The Fx allele is in very strong linkage disequilibrium with HLA-B17 as the linkage disequilibrium parameter accounted for nearly 100% of the haplotype frequency of B17,Fx. The strong association is also evidenced by the study of 11 families segregating for the Fx allele. There was no instance of recombination between C4 and HLA in 36 informative meioses.
Subject(s)
Complement C4/genetics , Genetic Variation , Adult , Child , Chromosome Mapping , Denmark , Female , Gene Frequency , Genes, Dominant , Genetic Linkage , HLA Antigens/genetics , Humans , Male , PhenotypeABSTRACT
Serum amyloid P component (SAP), a member of the conserved pentraxin family of plasma proteins, binds calcium dependently to its ligands. The authors investigated SAPs interaction with the complement proteins C4b binding protein (C4bp) and C1q by ELISA, immunoelectrophoresis and electron microscopy. Binding of these proteins to SAP was demonstrated when SAP was immobilized using F(ab')2 anti-SAP, but not when SAP reacted with these proteins in liquid phase; thus the binding to human SAP was markedly phase state dependent. Presaturation of solid phase SAP with heparin, which binds SAP with high affinity, did not interfere with the subsequent binding of C4bp or C1q to SAP. In contrast, collagen I and IV showed partial competition with the binding of C1q to SAP. Using fresh serum, immobilized native SAP bound C4bp whereas binding of C1q/C1 could not be demonstrated. Altogether the results indicate that firm binding of C1q and C4bp to SAP requires that SAP is presented on a solid phase, that C1q and C4bp react with sites distinct from the heparin binding site, and that C1q and collagen I share binding sites on SAP. Immobilized native SAP, aggregated SAP and SAP-heparansulphate complexes induced no detectable complement activation.
Subject(s)
Carrier Proteins/metabolism , Complement C1q/metabolism , Serum Amyloid P-Component/metabolism , Animals , Binding, Competitive , Complement Activation , Electrophoresis/methods , Enzyme-Linked Immunosorbent Assay , Heparitin Sulfate/metabolism , Humans , Integrin alphaXbeta2 , Protein Binding , RabbitsABSTRACT
Serum amyloid P component (SAP) and C-reactive protein (CRP) are members of the pentraxin protein family. SAP is the precursor protein to amyloid P component present in all forms of amyloidosis. The prevailing notion is that SAP in circulation has the form of a double pentameric molecule (decamer) whereas CRP is a single pentameric molecule. We have investigated by gel permeation chromatography the M(r) of SAP in freshly collected human serum and of SAP purified by carbohydrate affinity chromatography and anion exchange chromatography. SAP was monitored by quantitative immunoelectrophoresis and ELISA, and SAP peak fractions were analysed by use of SDS-PAGE, Western blotting, and electron microscopy. The results indicate that native SAP circulates as a single pentamer, a part of which forms complexes with C4b-binding protein. The properties of SAP changed during purification as indicated by rocket immunoelectrophoresis and electron microscopy. Thus, electron micrographs of purified SAP showed a predominance of decamers. However, the decamer form of SAP reversed to single pentamers when purified SAP was incorporated into SAP-depleted serum.
Subject(s)
Serum Amyloid P-Component/chemistry , Biopolymers/chemistry , Blotting, Western , Chromatography, Gel , Enzyme-Linked Immunosorbent Assay , Humans , Immunoelectrophoresis/methods , Microscopy, Electron , Serum Amyloid P-Component/ultrastructureABSTRACT
Human serum amyloid P component (SAP) isolated from 20 healthy individuals was analyzed by anion exchange chromatography and isoelectric focusing (IEF) in order to investigate the existence of multiple forms of SAP and interindividual structural differences. Anion exchange chromatography showed one major and several minor subpopulations of SAP. IEF of all SAP isolates showed a previously unreported degree of heterogeneity with six isoelectric forms (pKi range 5.5-6.1) and with minor interindividual differences in respect of isoelectric points. Total enzymatic deglycosylation of SAP reduced the number of bands in IEF to two indicating the existence of two types of polypeptide chains.
Subject(s)
Serum Amyloid P-Component/chemistry , Blood Proteins/chemistry , Blood Proteins/ultrastructure , Chromatography, Ion Exchange , Female , Humans , Isoelectric Focusing , Male , Microscopy, Electron , Molecular Structure , Serum Amyloid P-Component/ultrastructureABSTRACT
At least 12 different C4 gene products with a three band pattern have been identified after electrophoresis of sera pretreated with neuraminidase. Segregation analysis showed at least 12 different C4 haplotypes (or supergenes), of which five represent a single gene product and seven are duplications each composed of an F and an S gene. The data analyzed with respect to linkage showed one recombinant between the C4 and HLAB loci in 154 meioses giving a map distance of C4 HLAB of 0.6 cM. Another recombinant between the C4 and the HLAD loci was found in 101 meioses giving a map distance of C4 HLAD of 1.0 cM. Linkage disequilibrium was found between at least eight C4 haplotypes and certain alleles at the HLAB as well as the HLAD loci. Examinations of 15 families selected through a proband with HLAA 25, HLAB 18 and C2Q0 showed that in almost all cases a slight variant of the C4 supergene F3S2 followed the haplotype HLAA25 HLAB18 C2Q0. No associations were found between the two duplications of C4F3 C4S2 and C4F3 C4S1 and the loci. These findings may indicate that these C4 haplotypes were the original ones preceding the other C4 haplotypes.
Subject(s)
Complement C4/genetics , Genes , HLA Antigens/genetics , Adult , Child , Complement C2/genetics , Electrophoresis, Agar Gel , Female , Genetic Linkage , Histocompatibility Antigens Class II/genetics , Histocompatibility Testing , Humans , Male , PedigreeABSTRACT
Serum amyloid P component (SAP) binds in vitro to DNA; based on findings in SAP-deficient mice it was proposed that SAP's role is to handle chromatin and DNA, thereby preventing formation of anti-DNA antibodies. For the first time we have shown the presence of Ca2+-dependent SAP-DNA complexes, measured by ELISA, in sera from both healthy volunteers and systemic lupus erythematosus patients (SLE). The concentration of SAP-DNA complexes in SLE sera was significantly lower than in normal sera and particularly low in sera from patients with anti-DNA titers exceeding 50. The complexes were dissociated by the SAP ligand heparin and were not demonstrable in EDTA plasma. Normal sera showed similar capacity to form SAP-DNA complexes with both thymus and Escherichia coli DNA, whereas significantly lower amounts of complexes, in particular with E. coli DNA, were formed in SLE sera. SLE patients with moderate to high anti-DNA titers showed a significant negative correlation between serum SAP's binding of E. coli DNA and the anti-DNA titer.
Subject(s)
DNA/blood , Lupus Erythematosus, Systemic/blood , Serum Amyloid P-Component/metabolism , Antibodies, Antinuclear/immunology , Calcium/metabolism , DNA/metabolism , DNA, Bacterial/metabolism , Escherichia coli/genetics , Humans , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/metabolism , Macromolecular SubstancesABSTRACT
BACKGROUND: Cardiac surgery with cardiopulmonary bypass (CPB) evokes a systemic inflammatory response involving the proinflammatory cytokines tumor necrosis factor-alpha (TNFalpha), interleukin (IL)-1, IL-6, IL-8 and anti-inflammatory cytokines such as IL-10. Like IL-10, opioids downregulate the immune responses in vivo and in vitro, including the activity of the cytokine-producing monocytes and granulocytes. The proinflammatory cytokines are potent inducers of the hepatic acute-phase protein synthesis. The aim of the present study was to investigate if choice of anaesthesia, based on high-dose opioids (fentanyl) versus low-dose opioids influenced the release of IL-6, IL-8, and IL-10. Secondly, it was investigated whether serum amyloid P-component (SAP) is an acute-phase protein in man such as C-reactive protein (CRP), with which it is physically and structurally related. METHODS: Sixteen patients submitted to elective coronary artery bypass grafting (CABG) surgery were randomized to either low-dose opioid anaesthesia consisting of thoracic epidural analgesia combined with inhalational anaesthesia (group I) or high-dose fentanyl anaesthesia (group II). From each patient 18 blood samples were taken perioperatively. Cytokine analyses were performed with ELISA, CRP and SAP mere measured with rocket immunoelectrophoresis (RIE). RESULTS: Surgery and CPB elicited a marked, transient and almost simultaneous proinflammatory and anti-inflammatory cytokine response with no differences between the groups. The cytokine levels returned to preoperative levels 1-3 d after operation. Anaesthesia and surgery did not affect SAP plasma levels while patients showed a major increase in CRP concentrations preceding the cytokine responses. CONCLUSION: CABG performed during two different anaesthetic techniques, high-dose fentanyl versus low-dose opioid anaesthesia, elicited a well-defined cytokine response with minor variation in the time course of each cytokine. The cytokine production was not modified by type of anaesthesia. Finally, SAP is not an acute-phase protein in men.