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Yung S, Chan TM. Endothelial cell activation and glycocalyx shedding - potential as biomarkers in patients with lupus nephritis. Front Immunol 2023; 14:1251876. [PMID: 37854589 PMCID: PMC10579905 DOI: 10.3389/fimmu.2023.1251876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 09/18/2023] [Indexed: 10/20/2023] Open
Abstract
Lupus nephritis (LN) is a common and severe manifestation of systemic lupus erythematosus and an important cause of acute and chronic kidney injury. Early diagnosis of LN and preventing relapses are key to preserving renal reserve. However, due to the complexity and heterogeneity of the disease, clinical management remains challenging. Kidney biopsy remains the gold standard for confirming the diagnosis of LN and subsequent assessment of kidney histopathology, but it is invasive and cannot be repeated frequently. Current clinical indicators of kidney function such as proteinuria and serum creatinine level are non-specific and do not accurately reflect histopathological changes, while anti-dsDNA antibody and C3 levels reflect immunological status but not kidney injury. Identification of novel and specific biomarkers for LN is prerequisite to improve management. Renal function deterioration is associated with changes in the endothelial glycocalyx, a delicate gel-like layer located at the interface between the endothelium and bloodstream. Inflammation induces endothelial cell activation and shedding of glycocalyx constituents into the circulation. This review discusses the potential role of soluble glycocalyx components as biomarkers of active LN, especially in patients in whom conventional serological and biochemical markers do not appear helpful.
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Affiliation(s)
- Susan Yung
- Department of Medicine, School of Clinical Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Tak Mao Chan
- Department of Medicine, School of Clinical Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
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Sisto M, Ribatti D, Lisi S. Cadherin Signaling in Cancer and Autoimmune Diseases. Int J Mol Sci 2021; 22:ijms222413358. [PMID: 34948155 PMCID: PMC8704376 DOI: 10.3390/ijms222413358] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/06/2021] [Accepted: 12/08/2021] [Indexed: 02/07/2023] Open
Abstract
Cadherins mediate cell–cell adhesion through a dynamic process that is strongly dependent on the cellular context and signaling. Cadherin regulation reflects the interplay between fundamental cellular processes, including morphogenesis, proliferation, programmed cell death, surface organization of receptors, cytoskeletal organization, and cell trafficking. The variety of molecular mechanisms and cellular functions regulated by cadherins suggests that we have only scratched the surface in terms of clarifying the functions mediated by these versatile proteins. Altered cadherins expression is closely connected with tumorigenesis, epithelial–mesenchymal transition (EMT)-dependent fibrosis, and autoimmunity. We review the current understanding of how cadherins contribute to human health and disease, considering the mechanisms of cadherin involvement in diseases progression, as well as the clinical significance of cadherins as therapeutic targets.
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Komici K, Faris P, Negri S, Rosti V, García-Carrasco M, Mendoza-Pinto C, Berra-Romani R, Cervera R, Guerra G, Moccia F. Systemic lupus erythematosus, endothelial progenitor cells and intracellular Ca2+ signaling: A novel approach for an old disease. J Autoimmun 2020; 112:102486. [DOI: 10.1016/j.jaut.2020.102486] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/07/2020] [Accepted: 05/09/2020] [Indexed: 02/07/2023]
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McLeland S, Quimby J, Lappin MR. Alpha-enolase staining patterns in the renal tissues of cats with and without chronic kidney disease. Vet Immunol Immunopathol 2019; 212:23-26. [PMID: 31213248 DOI: 10.1016/j.vetimm.2019.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 04/04/2019] [Accepted: 04/30/2019] [Indexed: 11/25/2022]
Abstract
Renal α-enolase has variable expression in inflammatory and neoplastic diseases. Therefore, in order to define the distribution of α-enolase in renal tissues of cats, an immunohistochemistry assay was validated and described here. Tissues from 29 cats with IRIS Stage 2-4 CKD, 8 control cats < 2 years of age, and 4 control cats> 10 years of age were assessed. Interstitial nephritis was the predominant histopathological finding in the CKD group. The control cats < 2 years of age had moderate α-enolase immunoreactivity in tubular epithelium but staining was absent to mild in glomeruli. In contrast, α-enolase was moderate to high in tubular epithelium and glomeruli in control cats > 10 years of age. In cats with CKD, α-enolase was decreased in tubules that were degenerative or atrophic, similar to normal tubules in control groups, and moderate to high in glomeruli. When compared between the study groups, the results suggest that alpha-enolase decreases in damaged tubules and increases in the glomeruli of older cats prior to the development of detectable CKD. Further studies will be required to determine whether these findings relate to the pathogenesis or could be used in the diagnosis of feline CKD.
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Affiliation(s)
- Shannon McLeland
- From the Center for Companion Animal Studies, Department of Clinical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Jessica Quimby
- From the Center for Companion Animal Studies, Department of Clinical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Michael R Lappin
- From the Center for Companion Animal Studies, Department of Clinical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
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Endothelial Alterations in Systemic Lupus Erythematosus and Rheumatoid Arthritis: Potential Effect of Monocyte Interaction. Mediators Inflamm 2017; 2017:9680729. [PMID: 28546658 PMCID: PMC5435976 DOI: 10.1155/2017/9680729] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 03/22/2017] [Accepted: 03/23/2017] [Indexed: 12/20/2022] Open
Abstract
Patients with systemic autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) are prone to develop atherosclerosis and cardiovascular diseases five times more often than the general population; this increase in frequency could be partially explained by an increase in the macrovasculature endothelial damage. In these autoimmune diseases, a microvascular endothelial injury has also been reported in different organs and tissues, especially in sites where ultrafiltration processes occur. Different components that are characteristic to the immunopathology of RA and SLE could be involved in the endothelial cell activation, permeability increase, functional alteration, and vascular injury. Circulating immune complexes (IC) detected in SLE and RA have been proposed to participate in the endothelial injury. In the vascular environment, IC can generate different responses that could be mediated by monocytes, because these cells have patrolling and monitoring functions on the endothelium. However, with certain stimuli such as TLR ligands, the monocytes are retained in the lumen, releasing proinflammatory mediators that participate in the endothelial damage. This paper aims to review some aspects about the endothelial activation and dysfunction in the context of SLE and RA, as well as the potential role that monocytes apparently play in this process.
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Radic M, Marion TN. Neutrophil extracellular chromatin traps connect innate immune response to autoimmunity. Semin Immunopathol 2013; 35:465-80. [DOI: 10.1007/s00281-013-0376-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 03/18/2013] [Indexed: 01/08/2023]
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Troelsen LN, Garred P, Christiansen B, Torp-Pedersen C, Jacobsen S. Genetically determined serum levels of mannose-binding lectin correlate negatively with common carotid intima-media thickness in systemic lupus erythematosus. J Rheumatol 2010; 37:1815-21. [PMID: 20595266 DOI: 10.3899/jrheum.100158] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Patients with systemic lupus erythematosus (SLE) have excess cardiovascular morbidity and mortality due to accelerated atherosclerosis that cannot be attributed to traditional cardiovascular risk factors alone. Variant alleles of the mannose-binding lectin gene (MBL2) causing low serum concentrations of functional mannose-binding lectin (MBL) are associated with SLE and development of atherosclerosis. Recent studies show that these variant alleles are associated with increased risk of arterial thrombosis and cardiovascular disease in patients with SLE. Intima-media thickness of the common carotid artery (ccIMT) is a validated noninvasive anatomic measure of subclinical atherosclerosis. In a cross-sectional study we examined the relation among ccIMT, MBL2 genotypes, and serum concentrations of MBL. METHODS The MBL2 extended genotypes (YA/YA, YA/XA, XA/XA, YA/YO, XA/YO, YO/YO) and serum concentrations of MBL were determined in 41 outpatients with SLE. ccIMT was measured by means of ultrasonography. Traditional and nontraditional cardiovascular risk modifiers were assessed and controlled for. RESULTS Using nonparametric Mann-Whitney tests we found a significant difference in ccIMT between low-expressing (XA/XA+YA/YO+XA/YO+YO/YO) and high-expressing (YA/YA+YA/XA) MBL2 genotypes (p = 0.034). The difference in ccIMT remained significant in multivariable analysis adjusting for traditional and nontraditional cardiovascular risk modifiers (p = 0.049). ccIMT was negatively correlated to serum concentrations of MBL (Spearman rho = -0.33, p = 0.037). This relation also remained significant in multivariable analysis (p = 0.042). CONCLUSION In this group of SLE patients, MBL2 low-expressing genotypes and low serum levels of MBL were correlated with ccIMT, independent of the effects of traditional and nontraditional cardiovascular risk modifiers.
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Affiliation(s)
- Lone N Troelsen
- Department of Rheumatology, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.
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Wiik AS. Anti‐nuclear autoantibodies: clinical utility for diagnosis, prognosis, monitoring, and planning of treatment strategy in systemic immunoinflammatory diseases. Scand J Rheumatol 2009; 34:260-8. [PMID: 16195158 DOI: 10.1080/03009740500202664] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The determination of serum autoantibodies to nuclear and cytoplasmic cell components is relevant to the diagnosis of chronic immunoinflammatory disorders. Detection is based on screening methods that allow antibody binding to intact cell structures, followed by use of assays to demonstrate their antigen target specificity. The results can be used to help clinicians set diagnosis and estimate prognosis, plan further diagnostic work-up, monitoring strategy and sometimes therapeutic approach. To obtain such accuracy of use clinicians need to be involved in revealing the differential diagnostic potential of the autoimmune serology test programme by furnishing detailed clinical data on patients from whom serum samples have been obtained. Borders between positive and negative values should aim at attaining a high diagnostic specificity towards clinically important disease controls.
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Affiliation(s)
- A S Wiik
- Department of Autoimmunology, Statens Serum Institut, Copenhagen S, Denmark.
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Tobón GJ, Alard JE, Youinou P, Jamin C. Are autoantibodies triggering endothelial cell apoptosis really pathogenic? Autoimmun Rev 2009; 8:605-10. [PMID: 19393202 DOI: 10.1016/j.autrev.2009.02.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Accepted: 02/05/2009] [Indexed: 10/21/2022]
Abstract
Anti-endothelial cell (EC) antibodies (AECA) are a heterogeneous group of antibodies directed against a variety of EC membrane proteins. A pathogenic role for AECA in diseases that involve the vascular system has not been clearly demonstrated. Induction of EC apoptosis appears to be one of the mechanisms by which AECA may exert their effect. AECA from some patients trigger the translocation of anionic phospholipids, most notably phosphatidylserine, from the inner to the outer leaflet of the plasma membrane, and thereafter activation of caspase 3 and cleavage of poly (ADP-ribose) polymerase, hallmarks of apoptosis. Apoptotic cell death generates oxidatively modified moieties, which can induce autoimmune and local inflammatory responses. While a sole AECA target involved in the apoptotic process of ECs has not been identified, some evidence suggests that Heat Shock Proteins may be an outstanding antigen.
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Curiel RV, Bhagati R, Basavaraju L, Norton D, Katz J, Haile E, Weinstein A. Von Willebrand factor, red cell fragmentation, and disease activity in systemic lupus erythematosus. HSS J 2008; 4:170-4. [PMID: 18815861 PMCID: PMC2553164 DOI: 10.1007/s11420-008-9080-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Accepted: 06/03/2008] [Indexed: 02/07/2023]
Abstract
This study sought to determine whether the plasma levels of Von Willebrand factor (vWf) and the degree of red blood cell (RBC) fragmentation on peripheral smear correlate with disease activity in systemic lupus erythematosus (SLE). Forty consecutive patients who fulfilled the criteria for SLE were studied prospectively for 1 year. Patients were categorized according to the SLE Disease Activity Index (SLEDAI) as either active (>2) or inactive disease and followed up monthly (active) or quarterly (inactive). At each visit, patients were examined fully and had complete blood count, tests on antibodies to double-stranded DNA, C3, and C4 levels, and urinalysis. Citrated plasma was analyzed for vWf antigen by standard enzyme-linked immunosorbent assay. A Wright's stained blood smear was obtained and schistocytes were quantitated on blood smear. The number of schistocytes per 500 RBCs was determined and a schistocyte index (SI) was calculated. At baseline, vWf correlated with SLEDAI (r = 0.64, p < 0.01), SI correlated with SLEDAI (r = 0.62, p < 0.01), and vWf and SI correlated with each other (r = 0.41, p = 0.01). There was an inverse correlation between baseline C3 levels and vWf (r = 0.49, p = 0.0013) and C3 levels and SI (r = 0.40, p = 0.01). Over time, there was also a correlation of SLEDAI with vWf (r = 0.53, p = 0.002) and SI (r = 0.57;p = 0.002). The relation of vWf with SI approached but did not reach statistical significance (r = 0.37, p = 0.06). We found that the plasma levels of vWf and the degree of RBC fragmentation correlate with lupus disease activity over time. Therefore, inflammation in SLE may be associated with endothelial injury.
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Affiliation(s)
- Rodolfo V. Curiel
- Medical Faculty Associates, The George Washington University, 2150 Pennsylvania Avenue, Suite 3-416, Washington, DC 20037 USA
| | - Rajkumari Bhagati
- Medical Faculty Associates, The George Washington University, 2150 Pennsylvania Avenue, Suite 3-416, Washington, DC 20037 USA
| | - Lakshmi Basavaraju
- Medical Faculty Associates, The George Washington University, 2150 Pennsylvania Avenue, Suite 3-416, Washington, DC 20037 USA
| | - Delona Norton
- Medical Faculty Associates, The George Washington University, 2150 Pennsylvania Avenue, Suite 3-416, Washington, DC 20037 USA
| | - James Katz
- Medical Faculty Associates, The George Washington University, 2150 Pennsylvania Avenue, Suite 3-416, Washington, DC 20037 USA
| | - Elizabeth Haile
- Medical Faculty Associates, The George Washington University, 2150 Pennsylvania Avenue, Suite 3-416, Washington, DC 20037 USA
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Westerweel PE, Luyten RKMAC, Koomans HA, Derksen RHWM, Verhaar MC. Premature atherosclerotic cardiovascular disease in systemic lupus erythematosus. ACTA ACUST UNITED AC 2007; 56:1384-96. [PMID: 17469095 DOI: 10.1002/art.22568] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Alessandri C, Bombardieri M, Valesini G. Pathogenic mechanisms of anti-endothelial cell antibodies (AECA): their prevalence and clinical relevance. Adv Clin Chem 2006; 42:297-326. [PMID: 17131630 PMCID: PMC7119199 DOI: 10.1016/s0065-2423(06)42008-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Anti‐endothelial cell antibodies (AECA) represent a heterogeneous family of autoantibodies directed against structural endothelial proteins, as well as antigens adhering to endothelial cells. Although AECA immunoassays still show a high‐interlaboratory variability, several findings suggest a pathogenic role of these autoantibodies in diseases characterized by endothelial damage. In this chapter, we analyze the knowledge about AECA prevalence, clinical relevance, and their pathogenic role in autoimmune diseases focusing in particular on systemic lupus erythematosus, antiphospholipid syndrome, systemic sclerosis (SSc), and systemic vasculitis.
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Margutti P, Sorice M, Conti F, Delunardo F, Racaniello M, Alessandri C, Siracusano A, Riganò R, Profumo E, Valesini G, Ortona E. Screening of an endothelial cDNA library identifies the C-terminal region of Nedd5 as a novel autoantigen in systemic lupus erythematosus with psychiatric manifestations. Arthritis Res Ther 2005; 7:R896-903. [PMID: 15987492 PMCID: PMC1175040 DOI: 10.1186/ar1759] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2004] [Revised: 03/22/2005] [Accepted: 04/18/2005] [Indexed: 01/01/2023] Open
Abstract
Anti-endothelial-cell antibodies are associated with psychiatric manifestations in systemic lupus erythematosus (SLE). Our primary aim in this study was to seek and characterize molecules that behave as endothelial autoantigens in SLE patients with psychiatric manifestations. By screening a cDNA library from human umbilical artery endothelial cells with serum from an SLE patient with psychosis, we identified one positive strongly reactive clone encoding the C-terminal region (C-ter) of Nedd5, an intracytoplasmatic protein of the septin family. To evaluate anti-Nedd5 serum immunoreactivity, we analyzed by ELISA specific IgG responses in 17 patients with SLE and psychiatric manifestations (group A), 34 patients with SLE without psychiatric manifestations (group B), 20 patients with systemic sclerosis, 20 patients with infectious mononucleosis, and 35 healthy subjects. IgG specific to Nedd5 C-ter was present in 14 (27%) of the 51 SLE patients. The mean optical density value for IgG immunoreactivity to Nedd5 C-ter was significantly higher in patients of group A than in those of group B, those with infectious mononucleosis, or healthy subjects (0.17 ± 0.14 vs, respectively, 0.11 ± 0.07, P = 0.04; 0.11 ± 0.06, P = 0.034; and 0.09 ± 0.045, P = 0.003, on Student's t-test). Moreover, IgG immunoreactivity to Nedd5 C-ter was significantly higher in patients with systemic sclerosis than in patients of group B or healthy subjects (0.18 ± 0.18 vs, respectively, 0.11 ± 0.07, P = 0.046; and 0.09 ± 0.045, P = 0.003). The percentage of patients with anti-Nedd5 C-ter serum IgG was higher in group A than in group B (8 (47%) of 17, vs 6 (17%) of 34, P = 0.045, on Fisher's exact test). In order to clarify a possible mechanism by which Nedd5 might be autoantigenic, we observed that Nedd5 relocated from cytoplasm to the plasma membrane of EAhy926 endothelial cells after apoptotic stimuli. In conclusion, Nedd5 is a novel autoantigen of potential clinical importance that could be successfully used for a more thorough investigation of the pathogenesis of psychiatric manifestations in SLE. Although anti-Nedd5 autoantibodies are not specific to SLE, they are significantly associated with neuropsychiatric SLE and may represent immunological markers of psychiatric manifestations in this pathology.
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Affiliation(s)
- Paola Margutti
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Maurizio Sorice
- Dipartimento di Medicina Sperimentale e Patologia, Cattedra di Reumatologia, Università 'La Sapienza', Rome, Italy
| | - Fabrizio Conti
- Dipartimento di Clinica e Terapia Medica Applicata, Cattedra di Reumatologia, Università 'La Sapienza', Rome, Italy
| | - Federica Delunardo
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Mauro Racaniello
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Cristiano Alessandri
- Dipartimento di Clinica e Terapia Medica Applicata, Cattedra di Reumatologia, Università 'La Sapienza', Rome, Italy
| | - Alessandra Siracusano
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Rachele Riganò
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Elisabetta Profumo
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Guido Valesini
- Dipartimento di Clinica e Terapia Medica Applicata, Cattedra di Reumatologia, Università 'La Sapienza', Rome, Italy
| | - Elena Ortona
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
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Williams JM, Colman R, Brookes CJ, Savage CO, Harper L. Anti-endothelial cell antibodies from lupus patients bind to apoptotic endothelial cells promoting macrophage phagocytosis but do not induce apoptosis. Rheumatology (Oxford) 2005; 44:879-84. [PMID: 15827042 DOI: 10.1093/rheumatology/keh633] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE Anti-endothelial cell antibodies (AECA) have been reported to induce apoptosis. We investigated the induction of apoptosis by these autoantibodies and their involvement in the removal of apoptotic cells. METHODS AECA isolated from patients with active systemic lupus erythematosus (SLE) were incubated with human umbilical vein endothelial cells (HUVECs). AECA-positive sera were identified using a cell-based ELISA. Apoptosis was measured by morphology and phosphatidylserine externalization using flow cytometry with fluorescein isothiocyanate (FITC)-conjugated annexin V. Flow cytometry was used to investigate AECA binding to apoptotic cells using FITC-conjugated anti-human immunoglobulin G (IgG). Apoptotic endothelial cells were stained with a red dye (PKH26) and co-cultured with macrophages, and phagocytosis was visualized under phase contrast microscopy. RESULTS AECA from patients with SLE did not induce apoptosis compared with normal IgG (nIgG) at any time point, as assessed by morphology (at 24 h, P = 0.167) or phosphatidylserine externalization (at 24 h, P = 0.098). However, there was increased binding of AECA to apoptotic endothelial cells (48.8 +/- 11.9 compared with 25.8 +/- 6.7% AECA binding to freshly isolated cells, P< 0.001). These opsonized endothelial cells showed greater phagocytosis by macrophages (mean phagocytic index 24.9 +/- 4.5%) when cells opsonized with nIgG were compared with AECA (34.8 +/- 3.4% n = 5, P = 0.01). CONCLUSION In conclusion, AECA bind to apoptotic endothelial cells but do not induce endothelial cell apoptosis. Macrophage phagocytosis is increased by opsonization of apoptotic endothelial cells by AECA, a proinflammatory mechanism of cell removal.
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Affiliation(s)
- J M Williams
- Division of Immunity and Infection, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Margutti P, Delunardo F, Sorice M, Valesini G, Alessandri C, Capoano R, Profumo E, Siracusano A, Salvati B, Riganò R, Ortona E. Screening of a HUAEC cDNA library identifies actin as a candidate autoantigen associated with carotid atherosclerosis. Clin Exp Immunol 2004; 137:209-15. [PMID: 15196264 PMCID: PMC1809071 DOI: 10.1111/j.1365-2249.2004.02491.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The humoral immune response to endothelium has a pivotal role in the development of atherosclerosis. Using a molecular method, we sought to identify endothelial autoantigens in carotid atherosclerosis. Immunoscreening of a HUAEC expression library with IgG from a pool of two sera from patients with carotid atherosclerosis identified a clone specific to actin. We evaluated actin-specific IgG reactivity in patients with carotid atherosclerosis and compared responses with those in patients with systemic lupus erythematosus and type 1 diabetes mellitus and in healthy subjects. Enzyme-linked immunoassay detected actin-specific IgG in a significantly higher percentage of sera from patients with atherosclerosis and systemic lupus erythematosus than from healthy subjects (16/61, 26% and 13/33, 39%versus 2/41, 5%, P = 0.012 and P < 10(-4), by chi2 test). Mean optical density values were significantly higher in patients than in healthy subjects (P < 10(-4) by Student's t-test). Patients with atherosclerosis and uncomplicated plaques had significantly higher serum anti-actin IgG reactivity than those with complicated plaques (P = 0.048 by Student's t-test). Our findings suggest that actin is an autoantigenic molecule of potential clinical interest in carotid atherosclerosis.
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Affiliation(s)
- P Margutti
- Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy
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Autoantibody profile in systemic lupus erythematosus with psychiatric manifestations: a role for anti-endothelial-cell antibodies. Arthritis Res Ther 2004; 6:R366-72. [PMID: 15225372 PMCID: PMC464907 DOI: 10.1186/ar1198] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2004] [Revised: 05/07/2004] [Accepted: 05/18/2004] [Indexed: 01/27/2023] Open
Abstract
This study was performed to determine the correlation between psychiatric manifestations and several autoantibodies that might participate in the pathogenesis of psychiatric disorders in the course of systemic lupus erythematosus (SLE). Fifty-one unselected outpatients with SLE were enrolled. Psychiatric evaluation was performed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. The prevalence of antibodies against endothelial cells (AECA), cardiolipin, β2 glycoprotein I, Ro, Ro52, La, glial fibrillary acidic protein, ribosomal P protein, dsDNA, and nucleosomes was assessed by experimental and commercial enzyme-linked immunosorbent assays. According to the cutoff value, AECA were present in 11 of 17 (64.7%) SLE patients with psychosis and mood disorders and in 10 of 34 (29.4%) patients without psychiatric manifestations other than anxiety (P = 0.03). Moreover, the AECA binding index was significantly higher in the first group (P = 0.03). Conversely, no significant correlation was found between the presence of the other autoantibodies studied and psychiatric involvement. The results of this study suggest a relationship between AECA and psychosis and mood disorders in SLE, supporting the hypothesis of a biological origin of these disturbances.
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