| 1. |
- Lood, Christian, et al.
(författare)
-
IgG glycan hydrolysis by endoglycosidase S diminishes the proinflammatory properties of immune complexes from patients with systemic lupus erythematosus: A possible new treatment?
- 2012
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 64:8, s. 2698-2706
-
Tidskriftsartikel (refereegranskat)abstract
- Objective Systemic lupus erythematosus (SLE) is an autoimmune disease with chronic or episodic inflammation in several organ systems, related to the presence of circulating and tissue-deposited immune complexes (ICs) that stimulate leukocytes through Fc? receptors (Fc?R) with subsequent inflammation. Treatment with endoglycosidase S (EndoS), an IgG glycanhydrolyzing bacterial enzyme from Streptococcus pyogenes, has shown beneficial effects in several experimental animal models of chronic inflammatory disease. This study was undertaken to investigate whether EndoS affects the proinflammatory properties of ICs and has the potential to be developed as a therapy for SLE. Methods ICs purified from SLE patients or RNA-containing ICs formed in vitro were treated with EndoS and used in several assays reflecting different important features of SLE pathogenesis, such as phagocytosis by polymorphonuclear cells (PMNs) and plasmacytoid dendritic cells (PDCs), complement activation, and interferon-a (IFNa) production by PDCs. Results EndoS treatment abolished all proinflammatory properties of the ICs investigated. This included Fc?R-mediated phagocytosis by PDCs (P = 0.001) and subsequent production of IFNa (P = 0.002), IC-induced classical pathway of complement activation (P = 0.008), chemotaxis, and oxidative burst activity of PMNs (P = 0.002). EndoS treatment also had a direct effect on the molecular structure of ICs, causing decreased IC size and glycosylation. Conclusion Our findings indicate that EndoS treatment has prominent effects on several pathogenetically important IC-mediated events, and suggest that EndoS has the potential to be developed as a novel therapy for SLE.
|
|
| 2. |
- Lood, Christian, et al.
(författare)
-
IgG glycan hydrolysis by EndoS diminishes the pro-inflammatory properties of immune complexes from patients with SLE : a possible new treatment?
- 2012
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 0004-3591 .- 1529-0131. ; 64:8, s. 2698-2706
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVESystemic lupus erythematosus (SLE) is an autoimmune disease with chronic or episodic inflammation in several organ systems, related to the presence of circulating and tissue-deposited immune complexes (ICs) which stimulate leukocytes through FcγRs with subsequent inflammation. Treatment with EndoS, an IgG glycan hydrolyzing bacterial enzyme from Streptococcus pyogenes, has shown beneficial effects in several experimental animal models of chronic inflammatory disease. In the present study we asked if EndoS could affect pro-inflammatory properties of ICs and have the potential to be developed as a therapy in SLE.METHODSICs, purified from SLE patients or RNA-containing ICs formed in vitro, were treated with EndoS and used in several assays reflecting different important parts of SLE pathogenesis such as phagocytosis by polymorphonuclear neutrophils (PMNs) and plasmacytoid dendritic cells (pDCs), complement activation and IFNα production by pDCs.RESULTSOur results demonstrate that EndoS treatment could abolish all pro-inflammatory properties of ICs investigated. This includes FcγR-mediated phagocytosis by pDCs (p<0.0001) and subsequent production of IFNα (p<0.0001), IC-induced classical complement pathway activation (p<0.0001), chemotaxis and oxidative burst activity of PMNs (p=0.002). We could also demonstrate direct effects on the molecular structure of ICs after EndoS treatment with decreased size and glycosylation patterns.CONCLUSIONSProminent effects of EndoS treatment were seen in several pathogenetically important IC-mediated events and our data suggest that EndoS have the potential to be developed as a novel therapy in SLE.
|
|
| 3. |
|
|
| 4. |
- Allhorn, Maria, et al.
(författare)
-
The IgG specific endoglycosidase EndoS inhibits both cellular and complement mediated autoimmune hemolysis.
- 2010
-
Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 115:24, s. 5080-5088
-
Tidskriftsartikel (refereegranskat)abstract
- EndoS from Streptococcus pyogenes is an immunomodulating enzyme that specifically hydrolyzes glycans from human IgG and thereby affects antibody effector functions. Autoimmune hemolytic anemia is caused by antibody mediated red blood cell (RBC) destruction and often resists treatment with corticosteroids that also cause frequent adverse effects. We show here that anti-RhD (anti-D) and rabbit anti-human-RBC antibodies (anti-RBC) mediated destruction of RBC, i.e. phagocytosis, complement activation and hemolysis in vitro and in vivo was inhibited by EndoS. Phagocytosis by monocytes in vitro was inhibited by pre-treatment of anti-D with EndoS before sensitization of RBC, and abrogated by direct addition of EndoS to blood containing sensitized RBC. The toxic effects of monocytes stimulated with anti-D-sensitized RBC, as measured by interleukin-8 secretion and oxygen metabolite production, was restrained by EndoS. Agglutination of RBC and complement mediated hemolysis in vitro in whole human blood caused by rabbit anti-RBC was inhibited by EndoS. Development of anemia in mice caused by a murine anti-RBC IgG2a monoclonal autoantibody, and complement activation and erythrophagocytosis by Kupffer cells in the liver, were reduced by EndoS. Our data indicate that EndoS is a potential therapeutic agent that might be evaluated as an alternative to current treatment regimens against antibody mediated destruction of RBC.
|
|
| 5. |
- Andersson, Tilde, et al.
(författare)
-
Common skin bacteria protect their host from oxidative stress through secreted antioxidant RoxP
- 2019
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Cutibacterium acnes is an abundant skin commensal with several proposed mutualistic functions. A protein with strong antioxidant activity was recently identified from the C. acnes secretome. This protein, termed RoxP, facilitated aerobic bacterial growth in vitro and ex vivo. As reducing events naturally occurred outside of the bacterial cell, it was further hypothesized that RoxP could also serve to modulate redox status of human skin. The biological function of RoxP was here assessed in vitro and in vivo, through oxidatively stressed cell cultures and through protein quantification from skin affected by oxidative disease (actinic keratosis and basal cell carcinoma), respectively. 16S rDNA amplicon deep sequencing and single locus sequence typing was used to correlate bacterial prevalence to cutaneous RoxP abundances. We show that RoxP positively influence the viability of monocytes and keratinocytes exposed to oxidative stress, and that a congruent concentration decline of RoxP can be observed in skin affected by oxidative disease. Basal cell carcinoma was moreover associated with microbial dysbiosis, characterized by reduced C. acnes prevalence. C. acnes's secretion of RoxP, an exogenous but naturally occurring antioxidant on human skin, is likely to positively influence the human host. Results furthermore attest to its prospective usability as a biopharmaceutical.
|
|
| 6. |
- Bengtsson, Anders A., et al.
(författare)
-
Metabolic Profiling of Systemic Lupus Erythematosus and Comparison with Primary Sjögren’s Syndrome and Systemic Sclerosis
- 2016
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:7
-
Tidskriftsartikel (refereegranskat)abstract
- Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease which can affect most organ systems including skin, joints and the kidney. Clinically, SLE is a heterogeneous disease and shares features of several other rheumatic diseases, in particular primary Sjögrens syndrome (pSS) and systemic sclerosis (SSc), why it is difficult to diag- nose The pathogenesis of SLE is not completely understood, partly due to the heterogeneity of the disease. This study demonstrates that metabolomics can be used as a tool for improved diagnosis of SLE compared to other similar autoimmune diseases. We observed differences in metabolic profiles with a classification specificity above 67% in the comparison of SLE with pSS, SSc and a matched group of healthy individuals. Selected metabolites were also significantly different between studied diseases. Biochemical pathway analysis was conducted to gain understanding of underlying pathways involved in the SLE pathogenesis. We found an increased oxidative activity in SLE, supported by increased xanthine oxidase activity and an increased turnover in the urea cycle. The most discriminatory metabolite observed was tryptophan, with decreased levels in SLE patients compared to control groups. Changes of tryptophan levels were related to changes in the activity of the aromatic amino acid decarboxylase (AADC) and/or to activation of the kynurenine pathway.
|
|
| 7. |
- Bengtsson, Anders A., et al.
(författare)
-
Neutrophil FcγRIIA availability is associated with disease activity in systemic lupus erythematosus
- 2020
-
Ingår i: Arthritis Research and Therapy. - : Springer Science and Business Media LLC. - 1478-6354 .- 1478-6362. ; 22
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Immune complexes (ICs) are detectable in a variety of inflammatory diseases, including systemic lupus erythematosus (SLE), reflecting autoantibody binding to antigens. Though ICs are the main contributors to disease pathogenesis through FcγR-mediated inflammation and organ damage, IC levels are not part of the clinical assessment of SLE. The aim of this study was to explore the clinical utility of analyzing levels of ICs in SLE patients using a novel technology, IC-FLOW. Methods: Paired serum samples, at the time point of high and low disease activity (n = 92), were analyzed using two assays: an IC ELISA from a commercial company and a novel in-house flow cytometry-based method, IC-FLOW. IC-FLOW measures FcγRIIA availability on the neutrophil cell surface by flow cytometry, whereas the commercial ELISA measures IC binding to C1q. Results: Using IC-FLOW, 90% of SLE patients with active disease had elevated levels of circulating ICs (p < 0.0001). Using the commercial assay, only 17% of SLE patients had elevated levels of circulating ICs. For both assays, levels of ICs reflected active disease as determined by SLEDAI (r = 0.45, p < 0.0001) and were associated with type I IFN activity (r = 0.37, p = 0.001), and complement consumption (p = 0.0002). Levels of ICs measured with IC-FLOW, but not with the commercial ELISA, were associated with active lupus nephritis (p = 0.004). Conclusions: This novel FcγRIIA-IC assay can detect levels of circulating ICs in patients with SLE. Analyzing IC levels may facilitate monitoring of disease activity, as well as identify patients at risk of lupus nephritis, allowing for early preventive interventions.
|
|
| 8. |
- Bengtsson, Anders A, et al.
(författare)
-
Pharmacokinetics, tolerability, and preliminary efficacy of ABR-215757, a new quinoline-3-carboxamide derivative, in murine and human SLE
- 2012
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 0004-3591 .- 1529-0131. ; 64:5, s. 1579-1588
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To assess the efficacy of ABR-215757, a new immunomodulatory small molecule in a murine SLE model, to evaluate the pharmacokinetics and tolerability in SLE patients at doses predicted to be efficacious and safe, and to determine the maximum tolerated dose (MTD). METHODS: The efficacy of ABR-215757 was studied in lupus prone MRLlpr/lpr mice and compared with established SLE treatments. Dose response data of ABR-215757 were together with pharmacokinetic data used to calculate effective and safe clinical doses. The pharmacokinetics and tolerance of ABR-215757 were evaluated in a Phase Ib double-blind, placebo controlled, dose-escalation study where cohorts of SLE patients received daily oral treatment for 12 weeks. RESULTS: Disease inhibition in MRLlpr/lpr mice, comparable to that of prednisolone and mycophenolate mofetil, was obtained with ABR-215757. Prominent effects on disease manifestations, serological markers and a steroid sparing effect were seen for ABR-215757. The pharmacokinetic properties in SLE patients were linear and well suitable for once daily oral treatment. The majority of the adverse events (AEs) were mild or moderate and transient. The most frequent AEs were arthralgia and myalgia, reported at the highest (4.5 and 6 mg/day) dose levels. At 4.5 mg and higher some AEs of severe intensity and serious adverse events (SAEs) were reported. CONCLUSION: ABR-215757 effectively inhibited disease and had a steroid sparing effect in experimental lupus. Clinical doses up to 3 mg/day, dose levels predicted from pre-clinical studies to be efficacious and safe, were well tolerated in the SLE patients. The MTD was concluded to be 4.5 mg/day.
|
|
| 9. |
- Bengtsson, Anders, et al.
(författare)
-
Pharmacokinetics, tolerability, and preliminary efficacy of paquinimod (ABR-215757), a new quinoline-3-carboxamide derivative: Studies in lupus-prone mice and a multicenter, randomized, double-blind, placebo-controlled, repeat-dose, dose-ranging study in patients with systemic lupus erythematosus
- 2012
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 64:5, s. 1579-1588
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To assess the efficacy of paquinimod, a new immunomodulatory small molecule, in a murine lupus model, and to evaluate its pharmacokinetics and tolerability in systemic lupus erythematosus (SLE) patients at doses predicted to be efficacious and safe and determine the maximum tolerated dose. Methods The efficacy of paquinimod was studied in lupus-prone MRL-lpr/lpr mice and compared with that of established SLE treatments. Dose-response data and pharmacokinetic data were used to calculate effective and safe clinical doses of paquinimod. The pharmacokinetics and tolerability of paquinimod were evaluated in a phase Ib double-blind, placebo controlled, dose-ranging study in which cohorts of SLE patients received daily oral treatment for 12 weeks. Results Paquinimod treatment resulted in disease inhibition in MRL-lpr/lpr mice, comparable to that obtained with prednisolone and mycophenolate mofetil; prominent effects on disease manifestations and serologic markers and a steroid-sparing effect were observed. In patients with SLE, the pharmacokinetic properties of paquinimod were linear and well suitable for once-daily oral treatment. The majority of the adverse events (AEs) were mild or moderate, and transient. The most frequent AEs were arthralgia and myalgia, reported with the highest dose levels of paquinimod (4.5 mg/day and 6.0 mg/day). At the 4.5 mg/day dose level and higher, some AEs of severe intensity and serious adverse events were reported. Conclusion Paquinimod effectively inhibited disease and had a steroid-sparing effect in experimental lupus. Results from preclinical models together with pharmacokinetic data were successfully translated into a safe clinical dose range, and doses of up to 3.0 mg/day were well tolerated in the SLE patients. Taken together, the promising combined data from a murine model and human SLE support the future clinical development of paquinimod.
|
|
| 10. |
- Bäck, Jennie, et al.
(författare)
-
Contact activation products are new potential biomarkers to evaluate the risk of thrombotic events in systemic lupus erythematosus
- 2013
-
Ingår i: Arthritis Research & Therapy. - : Springer Science and Business Media LLC. - 1478-6362 .- 1478-6354. ; 15:6
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Patients with systemic lupus erythematosus (SLE) have persistent platelet activation and an increased risk of thrombotic events, which cannot be accounted for by traditional cardiovascular risk factors. Factor (F)XII has a potentially important role in thrombus formation and is triggered by activated platelets. We therefore asked whether the contact system is involved in inflammation and vascular disease (VD) in SLE. Methods: Fibrin clots were incubated with purified FXII or whole blood, and the activation and regulation of FXII were studied. Plasma from SLE patients with (n = 31) or without (n = 38) previous VD and from matched healthy controls (n = 68) were analyzed for the presence of complexes formed between contact system enzymes and antithrombin (AT) or C1 inhibitor (C1INH) and evaluated with regard to clinical data and laboratory parameters. Results: Fibrin clots elicited FXII activation and acted as co-factors for AT. In clotting plasma, the levels of FXIIa-AT increased, and FXIIa-C1INH decreased. A similar reciprocal relationship existed in SLE patients. FXIIa-AT was elevated in the SLE patients with a history of VD, while the corresponding levels of factor FXIIa-C1INH were significantly decreased. FXIIa-AT correlated strongly with platelet parameters. The odds ratio for VD among the SLE patients was 8.9 if they had low levels of FXIIa-C1INH, 6.1 for those with high levels of FXIIa-AT, and increased to 23.4 for those with both decreased levels of FXIIa-C1INH and increased levels of FXIIa-AT. Conclusions: Activation of FXII is elicited by fibrin during thrombotic reactions in vitro and in vivo, and fibrin acts as a heparin-like co-factor and regulates AT. Patients with SLE had altered levels of FXIIa-serpin complexes, supporting that the contact system is involved in this disease. FXIIa-serpin complexes are strongly associated with previous VD in SLE patients, suggesting that these complexes are potential biomarkers for monitoring and assessing the risk of thrombotic events in SLE.
|
|
| 11. |
|
|
| 12. |
- Carter, Victoria, et al.
(författare)
-
High Prevalence and Disease Correlation of Autoantibodies Against p40 Encoded by Long Interspersed Nuclear Elements in Systemic Lupus Erythematosus
- 2020
-
Ingår i: Arthritis and Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 72:1, s. 89-99
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Long interspersed nuclear element 1 (LINE-1) encodes 2 proteins, the RNA binding protein p40 and endonuclease and reverse transcriptase (open-reading frame 2p [ORF2p]), which are both required for LINE-1 to retrotranspose. In cells expressing LINE-1, these proteins assemble with LINE-1 RNA and additional RNA binding proteins, some of which are well-known autoantigens in patients with systemic lupus erythematosus (SLE). This study was undertaken to investigate whether SLE patients also produce autoantibodies against LINE-1 p40. Methods: Highly purified p40 protein was used to quantitate IgG autoantibodies in serum from 172 SLE patients and from disease controls and age-matched healthy subjects by immunoblotting and enzyme-linked immunosorbent assay (ELISA). Preparations of p40 that also contained associated proteins were analyzed by immunoblotting with patient sera. Results: Antibodies reactive with p40 were detected in the majority of patients and many healthy controls. Their levels were higher in patients with SLE, but not those with systemic sclerosis, compared to healthy subjects (P = 0.01). Anti-p40 reactivity was higher in patients during a flare than in patients with disease in remission (P = 0.03); correlated with the SLE Disease Activity Index score (P = 0.0002), type I interferon score (P = 0.006), decrease in complement C3 level (P = 0.0001), the presence of anti-DNA antibodies (P < 0.0001) and anti-C1q antibodies (P = 0.004), and current or past history of nephritis (P = 0.02 and P = 0.003, respectively); and correlated inversely with age (r = −0.49, P < 0.0001). SLE patient sera also reacted with p40-associated proteins. Conclusion: Autoantibodies reacting with LINE-1 p40 characterize a population of SLE patients with severe and active disease. These autoantibodies may represent an early immune response against LINE-1 p40 that does not yet by itself imply clinically significant autoimmunity, but may represent an early, and still reversible, step toward SLE pathogenesis.
|
|
| 13. |
- Compagno, Michele, et al.
(författare)
-
Plasma levels of osteopontin in SLE
- 2022
-
Ingår i: Lupus Science and Medicine. - : Lupus Foundation of America. - 2053-8790. ; 9:Suppl 2, s. 85-86
-
Konferensbidrag (refereegranskat)
|
|
| 14. |
|
|
| 15. |
- Gullstrand, Birgitta, et al.
(författare)
-
Combination of Autoantibodies Against Different Histone Proteins Influences Complement-dependent Phagocytosis of Necrotic Cell Material by Polymorphonuclear Leukocytes in Systemic Lupus Erythematosus.
- 2012
-
Ingår i: Journal of Rheumatology. - : The Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 39:8, s. 1619-1627
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Polymorphonuclear leukocytes (PMN) with autoantibody-coated engulfed necrotic cell material (NC) are frequently seen in systemic lupus erythematosus (SLE). We evaluated the roles of complement, different antihistone antibodies (anti-H ab), and oxidative burst in the phagocytosis of NC by PMN, as well as association to disease activity and clinical phenotype in SLE. METHODS: ELISA and immunoblot were used to measure antibodies to different histone proteins in sera from patients with SLE and complement-deficient individuals. Phagocytosis of NC by PMN and oxidative burst activity was assessed by flow cytometry. RESULTS: A clearly increased phagocytosis of NC was seen in patients with active SLE, which was associated with high levels of anti-H ab concentrations and oxidative burst activity. The complement system contributed to efficient phagocytosis of NC by PMN through activation of the classical pathway, and the phagocytosis was mediated by FcγRIIA, FcγRIIIB, and CR1 in combination. A pattern of high phagocytosis, consumption of classical pathway components, and a broad anti-H ab repertoire was seen particularly in patients with nephritis and serositis. The combination of antibodies to several different histone proteins, often with anti-DNA antibodies, promoted an efficient uptake of NC, whereas antibodies against only histone H1 or a few histones seemed to be of less importance. CONCLUSION: The distributions of specificities among anti-H ab are of great importance in the complement-dependent phagocytosis of debris from NC in SLE. Measurement of anti-H ab could be useful in monitoring of this disease and contribute to improved understanding of the autoimmune process.
|
|
| 16. |
- Han, Bobby Kwanghoon, et al.
(författare)
-
Neutrophil and lymphocyte counts are associated with different immunopathological mechanisms in systemic lupus erythematosus
- 2020
-
Ingår i: Lupus Science and Medicine. - : BMJ. - 2053-8790. ; 7:1
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Neutrophils contribute to the SLE pathogenesis. Neutrophil to lymphocyte ratio (NLR) is reported to correlate with disease activity in SLE. The aim of the study was to evaluate whether NLR reflects underlying immunopathogenic activity in SLE, as well as to determine the contribution of each component of NLR, neutrophil and lymphocyte count. Methods: Data were obtained from a cohort of patients with SLE (n=141) recruited at Lund University, Sweden. NLR levels were compared between patients with SLE and healthy controls (n=79). The relationship between NLR and clinical and immunological markers was examined using Mann-Whitney U test and logistic regression analysis. High NLR was defined as above the 90th percentile of healthy individuals. Results: Patients with SLE had elevated neutrophil count (p=0.04) and reduced lymphocyte count (p<0.0001), resulting in elevated NLR as compared with healthy controls (p<0.0001). Patients with high NLR had more active disease, and were more frequently on prednisone use and immunosuppressive medicines. High NLR was associated with immune complex (IC)-driven disease with presence of antidouble-stranded DNA antibodies (p=0.006), circulating ICs (p=0.02) and type I interferon (IFN) activity (p=0.009). Further, high NLR was associated with neutrophil abnormalities, including enrichment for low-density granulocytes (LDGs) (p=0.001), and increased levels of the serum neutrophil activation marker, calprotectin (p=0.02). Assessing the individual components within NLR, that is, neutrophil and lymphocyte count, high neutrophil count was associated with neutrophil activation markers (p<0.0001), whereas low lymphocyte count was associated with type I IFN activity and elevated numbers of LDGs (p=0.006 and p=0.001, respectively). Conclusions: NLR is elevated in patients with SLE as compared with healthy individuals, and is associated with key immunopathological events, including type I IFN activity and neutrophil activation. Neutrophil and lymphocyte count reflected different aspects of the pathogenesis of SLE. Further studies are needed to determine the causality of the associations.
|
|
| 17. |
- Jönsson, Göran, et al.
(författare)
-
Vaccination against encapsulated bacteria in hereditary C2 deficiency results in antibody response and opsonization due to antibody-dependent complement activation.
- 2012
-
Ingår i: Clinical Immunology. - : Elsevier BV. - 1521-6616. ; 144:3, s. 214-227
-
Tidskriftsartikel (refereegranskat)abstract
- Hereditary C2 deficiency (C2D) is an important susceptibility factor for invasive infections caused by encapsulated bacteria such as pneumococci and Haemophilus influenzae type b. The infections are mostly seen in childhood indicating that antibody-mediated acquired immunity is affected. C2D persons and healthy controls were vaccinated with ActHIB® and Pneumo23®. Analysis of specific antibodies to pneumococci serotype 6B, 7F, and 23F, and Hib was performed. Post-vaccination IgG antibodies against pneumococci serotype 6B and 23F at a concentration ≥1.0mg/L was found in similar frequency in C2D persons and controls. Post-vaccination sera from C2D persons showed poor complement-mediated opsonization and phagocytosis of pneumococci by granulocytes when depending on classical and lectin pathway activation only, but increased (p=0.007) and equaled that of the normal controls when also alternative pathway activation was allowed due to antibody-dependent C2 bypass activation. In conclusion, the C2D persons benefited from the vaccination and achieve an increased phagocytic capacity.
|
|
| 18. |
- Kander, Thomas, et al.
(författare)
-
Temperature effects on haemostasis in whole blood from ticagrelor- and aspirin-treated patients with acute coronary syndrome.
- 2015
-
Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - : Informa UK Limited. - 1502-7686 .- 0036-5513. ; 75:1, s. 27-35
-
Tidskriftsartikel (refereegranskat)abstract
- Background. Comatose survivors after cardiac arrest are treated with mild induced hypothermia and potent platelet- inhibiting drugs after coronary stenting. Previous studies have shown an increased incidence of stent thrombosis during clopidogrel and aspirin treatment in conjunction with induced hypothermia. The aim of this study was to investigate the in vitro effect of induced hypo- and hyperthermia on blood from patients undergoing ticagrelor- and aspirin-mediated platelet inhibition. Methods. Whole blood from 15 patients with acute coronary syndrome who were treated with ticagrelor and aspirin and from eight healthy volunteers was incubated for 1 hour at 28, 33, 37, and 39°C. Results. In blood from patients with acute coronary syndrome, the activated clotting time (Sonoclot) was prolonged in mild hypothermic (33°C) compared to normothermic (37°C) samples. Sonoclot, clotting rate and platelet function were decreased in hypothermic compared to normothermic samples. Platelet-induced activation and aggregation (Multiplate(®)) was unchanged in mild hypothermic compared to normothermic samples. In contrast, mild hypothermia supported increased platelet activation as measured with flow cytometry with up-regulation of PAC-1 and P-selectin on the platelet surface. Conclusion. In acute coronary syndrome patients treated with ticagrelor and aspirin, in vitro hypothermia to 33°C markedly increased platelet activity measured with flow cytometry, whereas viscoelastic coagulation test (Sonoclot) revealed a hypocoagulative response. Prospective clinical trials studying platelet inhibition at different temperatures and correlating changes in platelet function to bleeding or stent occlusion are needed.
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
- Kozarcanin, Huda, et al.
(författare)
-
The lectin complement pathway serine proteases (MASPs) represent a possible crossroad between the coagulation and complement systems in thromboinflammation
- 2016
-
Ingår i: Journal of Thrombosis and Haemostasis. - : Elsevier BV. - 1538-7933 .- 1538-7836. ; 14:3, s. 531-545
-
Tidskriftsartikel (refereegranskat)abstract
- The lectin pathway's MASP-1/2 activates coagulation factors but the trigger of the activation is unknown. MASP-1/2 activation was assessed by quantifying complexes between MASPs and antithrombin/C1-inhibitor. Activated platelets and fibrin were demonstrated to activate MASP-1 and MASP-2 both invitro and invivo. These findings may represent a crossroad between the complement and the coagulation systems. Summary Background The activated forms of the complement lectin pathway (LP) proteases MASP-1 and MASP-2 are able to cleave the coagulation factors prothrombin, fibrinogen, factor XIII and thrombin-activatable fibrinolysis inhibitor invitro. In vivo studies also show that MASP-1 is involved in thrombogenesis. Objectives To clarify the not yet identified mechanisms involved in triggering activation of the LP during thrombotic reactions. Methods Novel sandwich-ELISAs for detection of complexes between MASP-1 or MASP-2 and the serpins C1 inhibitor (C1-INH) or antithrombin (AT), were used to specifically detect and quantify the activated forms of MASP-1 and MASP-2. Results Activated platelets were shown by flow cytometry to bind Ficolin-1, -2 and -3 but not MBL, which was associated with activation of MASP-1 and MASP-2. We also demonstrated that fibrin and the plasmin-generated fibrin fragment DD in plasma, bind and activate MASP-1 and MASP-2. As demonstrated by the ELISA and SDS-PAGE/Western blotting, the fibrin-associated activation was reflected in a specific inactivation by AT during clotting without the assistance of heparin. In all other cases the MASPs were, as previously reported, inactivated by C1-INH. In systemic lupus erythematosus patients with thrombotic disease and in polytrauma patients, the levels of activated MASP-1 and MASP-2 in complex with both AT and C1-INH were associated with markers of thrombotic disease and contact/coagulation system activation. Conclusions MASP-1 and MASP-2 are activated during blood clotting. This activation is triggered by activated platelets and by the generation of fibrin during thrombotic reactions invitro and invivo, and may represent a novel activation/amplification mechanism in thromboinflammation.
|
|
| 22. |
- Kuley, Runa, et al.
(författare)
-
N-Formyl Methionine Peptide-Mediated Neutrophil Activation in Systemic Sclerosis
- 2022
-
Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- Exaggerated neutrophil activation and formation of neutrophil extracellular traps (NETs) are reported in systemic sclerosis (SSc) but its involvement in SSc pathogenesis is not clear. In the present study we assessed markers of neutrophil activation and NET formation in SSc patients in relation to markers of inflammation and disease phenotype. Factors promoting neutrophil activation in SSc remain largely unknown. Among the neutrophil activating factors, mitochondrial-derived N-formyl methionine (fMet) has been reported in several autoinflammatory conditions. The aim of the current study is to assess whether SSc patients have elevated levels of fMet and the role of fMet in neutrophil-mediated inflammation on SSc pathogenesis. Markers of neutrophil activation (calprotectin, NETs) and levels of fMet were analyzed in plasma from two SSc cohorts (n=80 and n=20, respectively) using ELISA. Neutrophil activation assays were performed in presence or absence of formyl peptide receptor 1 (FPR1) inhibitor cyclosporin H. Elevated levels of calprotectin and NETs were observed in SSc patients as compared to healthy controls (p<0.0001) associating with SSc clinical disease characteristics. Further, SSc patients had elevated levels of circulating fMet as compared to healthy controls (p<0.0001). Consistent with a role for fMet-mediated neutrophil activation, fMet levels correlated with levels of calprotectin and NETs (r=0.34, p=0.002; r=0.29, p<0.01 respectively). Additionally, plasma samples from SSc patients with high levels of fMet induced de novo neutrophil activation through FPR1-dependent mechanisms. Our data for the first time implicates an important role for the mitochondrial component fMet in promoting neutrophil-mediated inflammation in SSc.
|
|
| 23. |
- Leffler, Jonatan, et al.
(författare)
-
Neutrophil Extracellular Traps That Are Not Degraded in Systemic Lupus Erythematosus Activate Complement Exacerbating the Disease.
- 2012
-
Ingår i: Journal of immunology. - : The American Association of Immunologists. - 1550-6606 .- 0022-1767. ; 188:7, s. 3522-3531
-
Tidskriftsartikel (refereegranskat)abstract
- Ongoing inflammation including activation of the complement system is a hallmark of systemic lupus erythematosus (SLE). Antimicrobial neutrophil extracellular traps (NETs) are composed of secreted chromatin that may act as a source of autoantigens typical for SLE. In this study, we investigated how complement interacts with NETs and how NET degradation is affected by complement in SLE patients. We found that sera from a subset of patients with active SLE had a reduced ability to degrade in vitro-generated NETs, which was mostly restored when these patients were in remission. Patients that failed to degrade NETs had a more active disease and they also displayed lower levels of complement proteins C4 and C3 in blood. We discovered that NETs activated complement in vitro and that deposited C1q inhibited NET degradation including a direct inhibition of DNase-I by C1q. Complement deposition on NETs may facilitate autoantibody production, and indeed, Abs against NETs and NET epitopes were more pronounced in patients with impaired ability to degrade NETs. NET-bound autoantibodies inhibited degradation but also further increased C1q deposition, potentially exacerbating the disease. Thus, NETs are a potent complement activator, and this interaction may play an important role in SLE. Targeting complement with inhibitors or by removing complement activators such as NETs could be beneficial for patients with SLE.
|
|
| 24. |
- Linge, Petrus, et al.
(författare)
-
The non-haemostatic role of platelets in systemic lupus erythematosus
- 2018
-
Ingår i: Nature Reviews Rheumatology. - : Springer Science and Business Media LLC. - 1759-4790 .- 1759-4804. ; 14:4, s. 195-213
-
Forskningsöversikt (refereegranskat)abstract
- Dysregulation of lymphocyte function, accumulation of autoantibodies and defective clearance of circulating immune complexes and apoptotic cells are hallmarks of systemic lupus erythematosus (SLE). Moreover, it is now evident that an intricate interplay between the adaptive and innate immune systems contributes to the pathogenesis of SLE, ultimately resulting in chronic inflammation and organ damage. Platelets circulate in the blood and are chiefly recognized for their role in the prevention of bleeding and promotion of haemostasis; however, accumulating evidence points to a role for platelets in both adaptive and innate immunity. Through a broad repertoire of receptors, platelets respond promptly to immune complexes, complement and damage-associated molecular patterns, and represent a major reservoir of immunomodulatory molecules in the circulation. Furthermore, evidence suggests that platelets are activated in patients with SLE, and that they could contribute to the circulatory autoantigenic load through the release of microparticles and mitochondrial antigens. Herein, we highlight how platelets contribute to the immune response and review evidence implicating platelets in the pathogenesis of SLE.
|
|
| 25. |
- Liu Carlsen, Anting, et al.
(författare)
-
Circulating MicroRNA Expression Profiles Associated With Systemic Lupus Erythematosus
- 2013
-
Ingår i: Arthritis and Rheumatism. - : Wiley-Blackwell. - 0004-3591 .- 1529-0131. ; 65:5, s. 1324-1334
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To evaluate the specificity of expression patterns of cell-free circulating microRNAs (miRNAs) in systemic lupus erythematosus (SLE). Methods Total RNA was purified from plasma, and 45 different specific, mature miRNAs were determined using quantitative reverse transcriptionpolymerase chain reaction assays. A total of 409 plasma samples were obtained from 364 different patients with SLE, healthy control subjects, and control subjects with other autoimmune diseases. The results in the primary cohort of 62 patients with SLE and 29 healthy control subjects were validated in 2 independent cohorts: a validation cohort comprising 68 patients with SLE and 68 healthy control subjects, and a disease control cohort comprising 20 patients with SLE (19 of whom were from the other validation cohort), 46 healthy control subjects, 38 patients with vasculitis, 18 patients with rheumatoid arthritis, and 20 immunosuppressed patients. Results Seven miRNAs were statistically significantly differentially expressed in plasma from patients with SLE. The expression of miRNA-142-3p (miR-142-3p) and miR-181a was increased, and the expression of miR-106a, miR-17, miR-20a, miR-203, and miR-92a was decreased. In addition, the expression of miR-342-3p, miR-223, and miR-20a was significantly decreased in SLE patients with active nephritis. A predictive model for SLE based on 2 or 4 miRNAs differentiated patients with SLE from control subjects (76% accuracy) when validated independently (P andlt; 2 x 109). Use of the 4-miRNA model provided highly significant differentiation between the SLE group and disease controls, except for those with vasculitis. Conclusion Circulating miRNAs are systematically altered in SLE. A 4-miRNA signature was diagnostic of SLE, and a specific subset of miRNA profiles was associated with nephritis. All of the signature miRNAs target genes in the transforming growth factor signaling pathways. Other targets include regulation of apoptosis, cytokinecytokine receptors, T cell development, and cytoskeletal organization. These findings highlight possible dysregulated pathways in SLE and suggest that circulating miRNA patterns distinguish SLE from other immunoinflammatory phenotypes.
|
|
