1
|
Akbaba TH, Toor KK, Mann SK, Gibson KM, Alfaro GA, Balci-Peynircioglu B, Cabral DA, Morishita KA, Brown KL. Anti-LAMP-2 Antibody Seropositivity in Children with Primary Systemic Vasculitis Affecting Medium- and Large-Sized Vessels. Int J Mol Sci 2024; 25:3771. [PMID: 38612581 PMCID: PMC11011342 DOI: 10.3390/ijms25073771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 03/18/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
Chronic primary systemic vasculitis (PSV) comprises a group of heterogeneous diseases that are broadly classified by affected blood vessel size, clinical traits and the presence (or absence) of anti-neutrophil cytoplasmic antibodies (ANCA) against proteinase 3 (PR3) and myeloperoxidase (MPO). In small vessel vasculitis (SVV), ANCA are not present in all patients, and they are rarely detected in patients with vasculitis involving medium (MVV) and large (LVV) blood vessels. Some studies have demonstrated that lysosome-associated membrane protein-2 (LAMP-2/CD107b) is a target of ANCA in SVV, but its presence and prognostic value in childhood MVV and LVV is not known. This study utilized retrospective sera and clinical data obtained from 90 children and adolescents with chronic PSV affecting small (SVV, n = 53), medium (MVV, n = 16), and large (LVV, n = 21) blood vessels. LAMP-2-ANCA were measured in time-of-diagnosis sera using a custom electrochemiluminescence assay. The threshold for seropositivity was established in a comparator cohort of patients with systemic autoinflammatory disease. The proportion of LAMP-2-ANCA-seropositive individuals and sera concentrations of LAMP-2-ANCA were assessed for associations with overall and organ-specific disease activity at diagnosis and one-year follow up. This study demonstrated a greater time-of-diagnosis prevalence and sera concentration of LAMP-2-ANCA in MVV (52.9% seropositive) and LVV (76.2%) compared to SVV (45.3%). Further, LAMP-2-ANCA-seropositive individuals had significantly lower overall, but not organ-specific, disease activity at diagnosis. This did not, however, result in a greater reduction in disease activity or the likelihood of achieving inactive disease one-year after diagnosis. The results of this study demonstrate particularly high prevalence and concentration of LAMP-2-ANCA in chronic PSV that affects large blood vessels and is seronegative for traditional ANCA. Our findings invite reconsideration of roles for autoantigens other than MPO and PR3 in pediatric vasculitis, particularly in medium- and large-sized blood vessels.
Collapse
Affiliation(s)
- Tayfun Hilmi Akbaba
- BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada
- Division of Rheumatology, Department of Pediatrics, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Department of Medical Biology, Faculty of Medicine, Hacettepe University, 06800 Ankara, Turkey
| | - Kirandeep K. Toor
- BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada
- Women+ and Children’s Health Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Simranpreet K. Mann
- BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Kristen M. Gibson
- BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | | | - Banu Balci-Peynircioglu
- Department of Medical Biology, Faculty of Medicine, Hacettepe University, 06800 Ankara, Turkey
| | - David A. Cabral
- BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada
- Division of Rheumatology, Department of Pediatrics, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- BC Children’s Hospital, Vancouver, BC V6H 3V4, Canada
| | - Kimberly A. Morishita
- BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada
- Division of Rheumatology, Department of Pediatrics, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- BC Children’s Hospital, Vancouver, BC V6H 3V4, Canada
| | - Kelly L. Brown
- BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada
- Division of Rheumatology, Department of Pediatrics, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- BC Children’s Hospital, Vancouver, BC V6H 3V4, Canada
| |
Collapse
|
2
|
Nishibata Y, Matsuzawa S, Satomura Y, Ohtsuka T, Kuhara M, Masuda S, Tomaru U, Ishizu A. Neutrophil fixation protocols suitable for substrates to detect anti-neutrophil cytoplasmic antibodies by indirect immunofluorescence. Pathol Res Pract 2021; 228:153661. [PMID: 34749213 DOI: 10.1016/j.prp.2021.153661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 10/12/2021] [Accepted: 10/16/2021] [Indexed: 10/20/2022]
Abstract
Anti-neutrophil cytoplasmic antibodies (ANCAs) are autoantibodies that recognize neutrophil cytoplasmic antigens. The major ANCA antigens are myeloperoxidase and proteinase 3. Necrotizing small vessel vasculitis accompanied by ANCA production is called ANCA-associated vasculitis (AAV). In addition to AAV, ANCA is sometimes produced in patients with connective tissue diseases, such as systemic lupus erythematosus, and inflammatory bowel diseases. Indirect immunofluorescence (IIF) and enzyme immunoassay (EIA) have been used to detect ANCAs. Recently, the accuracy of EIA has improved and it has become the gold standard for ANCA detection. However, IIF does not lose its role in ANCA detection because EIA cannot detect ANCAs that recognize antigens other than those coated on the plate. For IIF, neutrophil substrates prepared with two different fixations, namely, ethanol fixation and formalin fixation, are used. There is a recommended protocol for ethanol fixation but not for formalin fixation. This study prepared neutrophil substrates according to the recommended protocol for ethanol fixation and protocols in the literature and original protocols for formalin fixation and then examined ANCA specificity and how storage period would influence the number of cells, antigen distribution, and antigenicity of the substrates. As a result, the number of cells and antigen distribution did not change after storage for up to 2 months regardless of fixation protocols, whereas a time-dependent decline in ANCA antigenicity and a fixation protocol-dependent difference in ANCA specificity were observed. How neutrophils are fixed on the glass slide needs to be checked upon evaluation of ANCAs by IIF.
Collapse
Affiliation(s)
- Yuka Nishibata
- Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Japan
| | | | | | | | | | - Sakiko Masuda
- Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Japan
| | - Utano Tomaru
- Department of Pathology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Japan
| | - Akihiro Ishizu
- Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Japan.
| |
Collapse
|
3
|
Gibson KM, Kain R, Luqmani RA, Ross CJ, Cabral DA, Brown KL. Autoantibodies Against Lysosome Associated Membrane Protein-2 (LAMP-2) in Pediatric Chronic Primary Systemic Vasculitis. Front Immunol 2021; 11:624758. [PMID: 33613565 PMCID: PMC7893977 DOI: 10.3389/fimmu.2020.624758] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 12/17/2020] [Indexed: 11/13/2022] Open
Abstract
Background Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a small vessel vasculitis in adults and children that commonly affects the kidneys. Although the frequent antigenic, and presumed pathogenic, targets of ANCA in AAV are proteinase-3 (PR3) and myeloperoxidase (MPO), ANCA against lysosome associated membrane protein-2 (LAMP-2), a lesser known ANCA antigen that is expressed on the glomerular endothelium, are present in some adults with AAV-associated renal disease. LAMP-2-ANCA has not been assessed in children with chronic systemic vasculitis, and, if present, would be a potentially valuable biomarker given that treatment decisions for these pediatric patients at diagnosis are largely informed by kidney function. Methods A custom ELISA, using commercially available reagents, was designed to detect autoantibodies to human LAMP-2 in serum. Sera obtained from 51 pediatric patients at the time of diagnosis of chronic primary systemic vasculitis (predominantly AAV) were screened. LAMP-2-ANCA titers were evaluated for correlation with clinical metrics of disease activity (pediatric vasculitis activity score [pVAS], C-reactive protein [CRP] concentration, and erythrocyte sedimentation rate [ESR]), MPO- and PR3-ANCA titers, and renal function (glomerular filtration rate [GFR], renal-specific pVAS, and serum creatinine concentration). Results LAMP-2-ANCA (>1,000 ng/ml) were detected in 35% (n = 18) of pediatric systemic vasculitis patients, of which, 10 (20% of all patients) were found to have high positive titers (>1,500 ng/ml). Undetectable or negative titres (<500 ng/ml) were identified in 12% (n = 6) of patients, those with titers between 500 and 1,000 ng/ml were considered low with unknown clinical relevance (53%, n = 27). Although LAMP-2-ANCA titers did not significantly differ between patients with AAV versus ANCA-negative vasculitis, only AAV patients had high concentrations (>1,500 ng/ml) of LAMP-2-ANCA. LAMP-2-ANCA titers did not correlate with measures of disease activity (pVAS, CRP, or ESR) at the time of diagnosis. In contrast, for patients with 12-month post diagnosis follow-up, a negative correlation was observed between the change in GFR (from diagnosis to 12-month follow-up) and LAMP-2-ANCA titer at diagnosis. Conclusions Moderate to high LAMP-2-ANCA titers were detected in 35% (18/51) of children with chronic systemic vasculitis affecting small-to-medium vessels. Although the highest concentrations of LAMP-2-ANCA in this population were observed in individuals positive for classic ANCA (MPO- or PR3-ANCA), similar to previous reports on adult patients, LAMP-2-ANCA titers do not correlate with classic ANCA titers or with overall disease activity at diagnosis. Renal disease is a common manifestation in systemic small-medium vessel vasculitis (both in adults and children, though more severe in children) and our preliminary data suggest LAMP-2-ANCA at diagnosis may be a risk factor for more severe renal disease.
Collapse
Affiliation(s)
- Kristen M Gibson
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada.,BC Children's Hospital Research Institute, Vancouver, BC, Canada
| | - Renate Kain
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Raashid A Luqmani
- Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Colin J Ross
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - David A Cabral
- Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada.,Division of Rheumatology, BC Children's Hospital, Vancouver, BC, Canada
| | - Kelly L Brown
- BC Children's Hospital Research Institute, Vancouver, BC, Canada.,Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada.,Centre for Blood Research, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
4
|
Sundqvist M, Gibson KM, Bowers SM, Niemietz I, Brown KL. Anti-neutrophil cytoplasmic antibodies (ANCA): Antigen interactions and downstream effects. J Leukoc Biol 2020; 108:617-626. [PMID: 32421916 DOI: 10.1002/jlb.3vmr0220-438rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 02/28/2020] [Accepted: 03/26/2020] [Indexed: 12/19/2022] Open
Abstract
Neutrophils are the most abundant leukocytes in circulation and are key "first responders" in the immune response to infectious and non-infectious stimuli. Unlike other immune cells, neutrophils can mount a robust response (including a change in surface markers and the production of extracellular traps and reactive oxygen species) just minutes after sensing a disturbance. It has been speculated that, in some individuals, the activation of neutrophils inadvertently leads to the generation of anti-neutrophil cytoplasmic autoantibodies (ANCA) against particular neutrophil proteins (antigens) such as myeloperoxidase (MPO) and proteinase 3 (PR3). In these individuals, continuous ANCA-antigen interactions are thought to drive persistent activation of neutrophils, chronic immune activation, and disease, most notably, small vessel vasculitis. There are significant gaps however in our understanding of the underlying mechanisms and even the pathogenicity of ANCA given that vasculitis can develop in the absence of ANCA, and that ANCA have been found in circulation in other conditions with no apparent contribution to disease. These gaps are particularly evident in the context of human studies. Herein, we review knowledge on neutrophil-derived ANCA antigens PR3 and MPO, ANCA generation, and ANCA-antigen interaction(s) that may promote immune activation and disease.
Collapse
Affiliation(s)
- Martina Sundqvist
- Department of Pediatrics, Division of Rheumatology, The University of British Columbia, Vancouver, British Columbia, Canada.,British Columbia Children's Hospital Research Institute, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Kristen M Gibson
- British Columbia Children's Hospital Research Institute, The University of British Columbia, Vancouver, British Columbia, Canada.,Department of Medical Genetics, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Sarah M Bowers
- British Columbia Children's Hospital Research Institute, The University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Blood Research, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Iwona Niemietz
- British Columbia Children's Hospital Research Institute, The University of British Columbia, Vancouver, British Columbia, Canada.,Department of Microbiology & Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Kelly L Brown
- Department of Pediatrics, Division of Rheumatology, The University of British Columbia, Vancouver, British Columbia, Canada.,British Columbia Children's Hospital Research Institute, The University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Blood Research, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
5
|
Moiseev S, Zykova A, Bulanov N, Gitel E, Novikov P, Bulanova M, Kronbichler A, Jayne D. Is There a Role for LAMP-2 Autoantibodies in Patients with Antineutrophil Cytoplasmic Antibody-associated Vasculitis? J Rheumatol 2020; 47:636-638. [PMID: 32062605 DOI: 10.3899/jrheum.191082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Sergey Moiseev
- Tareev Clinic of Internal Diseases, Sechenov First Moscow State Medical University, and Lomonosov Moscow State University;
| | - Anastasiia Zykova
- Tareev Clinic of Internal Diseases, Sechenov First Moscow State Medical University, and Lomonosov Moscow State University, Moscow, Russia
| | - Nikolay Bulanov
- Tareev Clinic of Internal Diseases, Sechenov First Moscow State Medical University
| | | | - Pavel Novikov
- Tareev Clinic of Internal Diseases, Sechenov First Moscow State Medical University
| | | | - Andreas Kronbichler
- Department of Internal Medicine IV (Nephrology and Hypertension), Medical University Innsbruck, Innsbruck, Austria
| | - David Jayne
- Department of Medicine, University of Cambridge, Cambridge, UK
| |
Collapse
|
6
|
van Dam LS, Rabelink TJ, van Kooten C, Teng YKO. Clinical Implications of Excessive Neutrophil Extracellular Trap Formation in Renal Autoimmune Diseases. Kidney Int Rep 2018; 4:196-211. [PMID: 30775617 PMCID: PMC6365354 DOI: 10.1016/j.ekir.2018.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/02/2018] [Accepted: 11/12/2018] [Indexed: 12/20/2022] Open
Abstract
Neutrophil extracellular traps (NETs) are extracellular DNA structures covered with antimicrobial peptides, danger molecules, and autoantigens that can be released by neutrophils. NETs are an important first-line defense mechanism against bacterial, viral, fungal, and parasitic infections, but they can also play a role in autoimmune diseases. NETs are immunogenic and toxic structures that are recognized by the autoantibodies of patients with antineutrophil cytoplasmic antibodies−associated vasculitis (AAV) (i.e., against myeloperoxidase or proteinase-3) and systemic lupus erythematosus (SLE) (i.e., against double-stranded DNA, histones, or nucleosomes). There is cumulating preclinical and clinical evidence that both excessive formation and impaired degradation of NETs are involved in the pathophysiology of AAV and SLE. These autoimmune diseases give rise to 2 clinically and pathologically distinct forms of glomerulonephritis (GN), respectively, crescentic pauci-immune GN and immune complex−mediated GN. Therefore, it is relevant to understand the different roles NET formation can play in the pathophysiology of these most prevalent renal autoimmune diseases. This review summarizes the current concepts on the role of NET formation in the pathophysiology of AAV and SLE, and provides a translational perspective on the clinical implications of NETs, such as potential therapeutic approaches that target NET formation in these renal autoimmune diseases.
Collapse
Affiliation(s)
- Laura S van Dam
- Department of Nephrology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Ton J Rabelink
- Department of Nephrology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Cees van Kooten
- Department of Nephrology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Y K Onno Teng
- Department of Nephrology, Leiden University Medical Centre, Leiden, The Netherlands
| |
Collapse
|
7
|
Langlois V, Marie I. Endocardites infectieuses associées aux anticorps anticytoplasme des polynucléaires neutrophiles (ANCA) : revue de la littérature. Rev Med Interne 2017; 38:450-457. [DOI: 10.1016/j.revmed.2016.12.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 12/15/2016] [Accepted: 12/26/2016] [Indexed: 12/19/2022]
|
8
|
Abstract
Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is characterized as inflammation of small-sized to medium-sized blood vessels and encompasses several clinicopathologic entities including granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, and renal-limited ANCA-associated vasculitis. Over the past several decades, significant progress has been made in understanding the pathophysiology of ANCA-associated vasculitis. Although neutrophils contain a multitude of granular proteins, clinically significant autoantibodies are only recognized against myeloperoxidase and proteinase 3, both of which are present in the azurophilic granules. The propensity to develop these antibodies depends on a variety of predisposing factors such as microbial infection, genetic factors, environmental agents, and therapeutic drugs among others. These factors are usually associated with production of proinflammatory cytokines with capacity to prime the neutrophils. As a result a high proportion of neutrophils in circulation may be primed resulting in exposure of cytoplasmic proteins including myeloperoxidase and proteinase 3 on the surface of the neutrophils. Primed neutrophils are activated by interaction with ANCA in circulation. Activated neutrophils attach to and transmigrate through endothelium and accumulate within the vessel wall. These neutrophils degranulate and produce reactive oxygen radicals and ultimately die, causing tissue injury. Endothelial injury results in leakage of serum proteins and coagulation factors causing fibrinoid necrosis. B cells produce ANCAs, as well as neutrophil abnormalities and imbalances in different T-cell subtypes with excess of Th17, which perpetuate the inflammatory process.
Collapse
|
9
|
Anwar S, Karim MY. Update on systemic vasculitides. J Clin Pathol 2017; 70:476-482. [PMID: 28377447 DOI: 10.1136/jclinpath-2016-203875] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 02/08/2017] [Accepted: 02/23/2017] [Indexed: 02/02/2023]
Abstract
Management of systemic vasculitis has been revolutionised over the last decade with the introduction of targeted biological agents. With an increase in both the prevalence and the recognition of vasculitis as well as the high cost of these agents, it is important to ensure their most optimal utilisation. The goals of vasculitis therapy include the induction and maintenance of remissions, preventing relapses, reducing the toxicity of therapy with the aim of reducing morbidity and mortality as well as improving the quality of life of those afflicted. This review focuses on the recent advances in the diagnosis, surveillance and treatment of these conditions.
Collapse
Affiliation(s)
- Siddiq Anwar
- Department of Medicine, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - M Yousuf Karim
- Immunology Department, Frimley Park Hospital, Frimley, UK
| |
Collapse
|
10
|
Androsova TV, Kozlovskaya LV, Taranova MV, Strizhakov LA, Gulyaev SV, Russkikh AV. Difficulties in the differential diagnosis of kidney injury in a patient with infective endocarditis associated with antineutrophil cytoplasmic antibodies. TERAPEVT ARKH 2017; 89:84-88. [DOI: 10.17116/terarkh201789684-88] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
11
|
Loke I, Kolarich D, Packer NH, Thaysen-Andersen M. Emerging roles of protein mannosylation in inflammation and infection. Mol Aspects Med 2016; 51:31-55. [PMID: 27086127 DOI: 10.1016/j.mam.2016.04.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/05/2016] [Accepted: 04/10/2016] [Indexed: 02/07/2023]
Abstract
Proteins are frequently modified by complex carbohydrates (glycans) that play central roles in maintaining the structural and functional integrity of cells and tissues in humans and lower organisms. Mannose forms an essential building block of protein glycosylation, and its functional involvement as components of larger and diverse α-mannosidic glycoepitopes in important intra- and intercellular glycoimmunological processes is gaining recognition. With a focus on the mannose-rich asparagine (N-linked) glycosylation type, this review summarises the increasing volume of literature covering human and non-human protein mannosylation, including their structures, biosynthesis and spatiotemporal expression. The review also covers their known interactions with specialised host and microbial mannose-recognising C-type lectin receptors (mrCLRs) and antibodies (mrAbs) during inflammation and pathogen infection. Advances in molecular mapping technologies have recently revealed novel immuno-centric mannose-terminating truncated N-glycans, termed paucimannosylation, on human proteins. The cellular presentation of α-mannosidic glycoepitopes on N-glycoproteins appears tightly regulated; α-mannose determinants are relative rare glycoepitopes in physiological extracellular environments, but may be actively secreted or leaked from cells to transmit potent signals when required. Simultaneously, our understanding of the molecular basis on the recognition of mannosidic epitopes by mrCLRs including DC-SIGN, mannose receptor, mannose binding lectin and mrAb is rapidly advancing, together with the functional implications of these interactions in facilitating an effective immune response during physiological and pathophysiological conditions. Ultimately, deciphering these complex mannose-based receptor-ligand interactions at the detailed molecular level will significantly advance our understanding of immunological disorders and infectious diseases, promoting the development of future therapeutics to improve patient clinical outcomes.
Collapse
Affiliation(s)
- Ian Loke
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Daniel Kolarich
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany
| | - Nicolle H Packer
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Morten Thaysen-Andersen
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW 2109, Australia.
| |
Collapse
|
12
|
Langlois V, Lesourd A, Girszyn N, Ménard JF, Levesque H, Caron F, Marie I. Antineutrophil Cytoplasmic Antibodies Associated With Infective Endocarditis. Medicine (Baltimore) 2016; 95:e2564. [PMID: 26817911 PMCID: PMC4998285 DOI: 10.1097/md.0000000000002564] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 12/17/2015] [Accepted: 12/28/2015] [Indexed: 12/23/2022] Open
Abstract
To determine the prevalence of antineutrophil cytoplasmic antibodies (ANCA) in patients with infective endocarditis (IE) in internal medicine; and to compare clinical and biochemical features and outcome between patients exhibiting IE with and without ANCA.Fifty consecutive patients with IE underwent ANCA testing. The medical records of these patients were reviewed.Of the 50 patients with IE, 12 exhibited ANCA (24%). ANCA-positive patients with IE exhibited: longer duration between the onset of first symptoms and IE diagnosis (P = 0.02); and more frequently: weight loss (P = 0.017) and renal impairment (P = 0.08), lower levels of C-reactive protein (P = 0.0009) and serum albumin (P = 0.0032), involvement of both aortic and mitral valves (P = 0.009), and longer hospital stay (P = 0.016). Under multivariate analysis, significant factors for ANCA-associated IE were: longer hospital stay (P = 0.004), lower level of serum albumin (P = 0.02), and multiple valve involvement (P = 0.04). Mortality rate was 25% in ANCA patients; death was because of IE complications in all these patients.Our study identifies a high prevalence of ANCA in unselected patients with IE in internal medicine (24%). Our findings further underscore that ANCA may be associated with a subacute form of IE leading to multiple valve involvement and more frequent renal impairment. Because death was due to IE complications in all patients, our data suggest that aggressive therapy may be required to improve such patients' outcome.
Collapse
Affiliation(s)
- Vincent Langlois
- From the Department of Internal Medicine, Institute for Biochemical Research, IFRMP, University of Rouen (VL, AL, NG, HL, IM); Department of Infectious diseases (FC); and Department of Biostatistics (J-F M), CHU Rouen, France
| | | | | | | | | | | | | |
Collapse
|
13
|
Pauci-Immune Crescentic Glomerulonephritis: An ANCA-Associated Vasculitis. BIOMED RESEARCH INTERNATIONAL 2015; 2015:402826. [PMID: 26688808 PMCID: PMC4673333 DOI: 10.1155/2015/402826] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 11/15/2015] [Accepted: 11/17/2015] [Indexed: 01/18/2023]
Abstract
Rapidly progressive glomerulonephritis (RPGN) is a syndrome signified by a precipitous loss of renal function, with features of glomerulonephritis including dysmorphic erythrocyturia and glomerular proteinuria. RPGN is associated with extensive crescent formation, and, thus, the clinical term RPGN is often used interchangeably with the pathologic term crescentic glomerulonephritis (CGN). From an immunopathologic standpoint, primary RPGN is divided into pauci-immune GN (PICG), anti-GBM GN, and immune complex GN. PICG, the most common etiology of primary RPGN, refers to a necrotizing glomerulonephritis with few or no immune deposits by immunofluorescence (IF) or electron microscopy (EM). In most patients, pauci-immune CGN is a component of a systemic small vessel vasculitis such as granulomatosis with polyangiitis (GPA). Approximately 90% of patients with PICG have circulating ANCA antibodies, leading to the nomenclature ANCA-associated vasculitis (AAV). Recent research has identified several other antibodies associated with PICG, which is now understood to be a complex spectrum of disease with considerable overlap in terms of clinical phenotype and outcomes. In addition, several genetic and environmental factors have recently been implicated in the pathogenesis of this disorder. With new prognostic classifications, enhanced understanding of immunopathologic mechanisms, and novel treatment paradigms, clinical and experimental interest in PICG remains high.
Collapse
|
14
|
Rowaiye OO, Kusztal M, Klinger M. The kidneys and ANCA-associated vasculitis: from pathogenesis to diagnosis. Clin Kidney J 2015; 8:343-50. [PMID: 26034600 PMCID: PMC4440467 DOI: 10.1093/ckj/sfv020] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 03/05/2015] [Indexed: 12/20/2022] Open
Abstract
Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are a group of pauci-immune small vessel vasculitides that often affect the kidneys manifesting as rapidly progressive glomerulonephritis. Although the exact pathogenesis of AAV is not fully known, evidence from in vitro, in vivo and clinical studies all point to the involvement of ANCA in the pathogenesis of AAV. In this review, we highlight the contributory roles played by various factors (e.g. genetics, environment, B and T-regulatory cells, toll-like receptors, etc.) in the pathogenesis of AAV. Furthermore, we discuss renal involvement in AAV in terms of clinical features and the various histopathological classification patterns, which are also known to be of prognostic importance. We also present information on useful imaging techniques for localizing kidney and other organ system involvement in AAV, and also on novel laboratory methods and assays useful for rapid and more specific determination of patients' ANCA status. Finally, we demonstrate evidence on novel serum biomarkers that have been shown to correlate with disease activity in AAV.
Collapse
Affiliation(s)
| | - Mariusz Kusztal
- Department of Nephrology and Transplantation Medicine , Wroclaw Medical University , Wroclaw , Poland
| | - Marian Klinger
- Department of Nephrology and Transplantation Medicine , Wroclaw Medical University , Wroclaw , Poland
| |
Collapse
|
15
|
Konstantinov KN, Ulff-Møller CJ, Tzamaloukas AH. Infections and antineutrophil cytoplasmic antibodies: triggering mechanisms. Autoimmun Rev 2014; 14:201-3. [PMID: 25448042 DOI: 10.1016/j.autrev.2014.10.020] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 10/21/2014] [Indexed: 01/25/2023]
Abstract
The precise cause of the antineutrophil cytoplasmic antibodies (ANCA) autoimmunity is not known and is likely to be multifactorial. Infections may trigger formation of ANCA and a fraction of the patients with infection-triggered ANCA develop ANCA-associated vasculitis. Here we discuss some of the proposed mechanisms of ANCA formation during the course of infection. They include initiation of autoimmune response by microbial peptides that are complementary to autoantigens; epigenetic silencing and antigen complementarity leading to upregulation of autoantigen genes; molecular mimicry between bacterial and self-antigens; formation of neutrophil extracellular traps that stimulate immune processes including production of ANCA; and interaction of bacterial components with Toll-like receptors, which leads to formation of mediators affecting the immune responses to infections and can trigger ANCA production. Further work is needed to clarify these mechanisms and develop preventive measures and therapeutic interventions.
Collapse
Affiliation(s)
- Konstantin N Konstantinov
- Division of Rheumatology, Department of Internal Medicine, University of New Mexico School of Medicine Health Sciences Center, Mail Stop MSC10-5550, Albuquerque, NM 87131, USA.
| | - Constance J Ulff-Møller
- Department of Infectious Diseases and Rheumatology, Rigshospitalet, Copenhagen, University Hospital, Blegdamsvej 9, DK-2100 Denmark.
| | - Antonios H Tzamaloukas
- Section of Nephrology, Raymond G. Murphy Veterans Affairs Medical Center and University of New Mexico School of Medicine, Renal Section, VA Medical Center, 1501 San Pedro, SE, Albuquerque, NM 87108, USA.
| |
Collapse
|
16
|
Najem C, Sfeir M, Estrada E, Mbuyi N, Valicenti D, Reginato AM. An unusual case of hematuria. Arthritis Care Res (Hoboken) 2014; 66:1119-26. [PMID: 24578326 DOI: 10.1002/acr.22315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/18/2014] [Indexed: 11/06/2022]
|
17
|
Abstract
The small-vessel vasculitides are a group of disorders characterised by variable patterns of small blood vessel inflammation producing a markedly heterogeneous clinical phenotype. While any vessel in any organ may be involved, distinct but often overlapping sets of clinical features have allowed the description of three subtypes associated with the presence of circulating anti-neutrophil cytoplasmic antibodies (ANCA), namely granulomatosis with polyangiitis (GPA, formerly known as Wegener’s Granulomatosis), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (eGPA, formerly known as Churg-Strauss syndrome). Together, these conditions are called the ANCA-associated vasculitidies (AAV). Both formal nomenclature and classification criteria for the syndromes have changed repeatedly since their description over 100 years ago and may conceivably do so again following recent reports showing distinct genetic associations of patients with detectable ANCA of distinct specificities. ANCA are not only useful in classifying the syndromes but substantial evidence implicates them in driving disease pathogenesis although the mechanism by which they develop and tolerance is broken remains controversial. Advances in our understanding of the pathogenesis of the syndromes have been accompanied by some progress in treatment, although much remains to be done to improve the chronic morbidity associated with the immunosuppression required for disease control.
Collapse
|
18
|
|