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Pisetsky DS, Shaffer R, Armstrong DD, Spencer DM. The interaction of anti-DNA antibodies with DNA antigen: Evidence for hysteresis for high avidity binding. Clin Immunol 2021; 231:108848. [PMID: 34492381 DOI: 10.1016/j.clim.2021.108848] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 07/11/2021] [Accepted: 09/02/2021] [Indexed: 10/20/2022]
Abstract
Antibodies to DNA (anti-DNA) are the serological hallmark of systemic lupus erythematosus. Previous studies have indicated that the phosphodiester backbone is the main antigenic target, with electrostatic interactions important for high avidity. To define further these interactions, the effects of ionic strength on anti-DNA binding of SLE plasmas were assessed in association and dissociation assays by ELISA. As these studies demonstrated, increasing ionic strength to a concentration of 1000 mM NaCl reduced antibody binding although the extent of the reduction varied among samples. In dissociation assays, differences among plasmas were also observed. For one of the plasmas, binding to DNA displayed resistance to dissociation by increasing ionic strength even though these concentrations limited binding in association assays. Time course studies showed a gradual change in binding interactions. These studies indicate that anti-DNA binding can involve both electrostatic and non-electrostatic interactions, with binding in some plasmas showing evidence of hysteresis.
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Affiliation(s)
- David S Pisetsky
- Medical Research Service, Durham Veterans Administration Medical Center, Durham, NC 27705, USA; Division of Rheumatology and Immunology, Duke University Medical Center, Durham, NC 27710, USA.
| | | | | | - Diane M Spencer
- Division of Rheumatology and Immunology, Duke University Medical Center, Durham, NC 27710, USA
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2
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Shigesaka M, Ito T, Inaba M, Imai K, Yamanaka H, Azuma Y, Tanaka A, Amuro H, Nishizawa T, Son Y, Satake A, Ozaki Y, Nomura S. Mycophenolic acid, the active form of mycophenolate mofetil, interferes with IRF7 nuclear translocation and type I IFN production by plasmacytoid dendritic cells. Arthritis Res Ther 2020; 22:264. [PMID: 33168076 PMCID: PMC7654586 DOI: 10.1186/s13075-020-02356-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 10/18/2020] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Both humoral and cellular immune mechanisms are involved in the onset and progression of autoimmune responses in systemic lupus erythematosus (SLE). Plasmacytoid dendritic cells (pDCs) play a central role in the pathogenesis of SLE via the dysregulation of type I interferon (IFN) production; these cells act together with activated myeloid DCs (mDCs) to amplify the vicious pathogenic spiral of autoimmune disorders. Therefore, control of aberrant DC activation in SLE may provide an alternative treatment strategy against this disease. Mycophenolate mofetil (MMF), which has been used to treat lupus nephritis, specifically blocks the proliferation of B and T lymphocytes via inhibition of inosine-5-monophosphate dehydrogenase. Here, we focus on the effects of MMF in targeting DC functions, especially the IFN response of pDCs. METHODS We isolated human blood pDCs and mDCs by flow cytometry and examined the effect of mycophenolic acid (MPA), which is a metabolic product of MMF, on the toll-like receptor (TLR) ligand response of DC subsets. Additionally, we cultured pDCs with serum from SLE patients in the presence or absence of MPA and then examined the inhibitory function of MPA on SLE serum-induced IFN-α production. RESULTS We found that treatment with 1-10 μM of MPA (covering the clinical trough plasma concentration range) dose-dependently downregulated the expression of CD80 and CD86 on mDCs (but not pDCs) without inducing apoptosis, in response to R848 or CpG-ODN, respectively. Notably, in pDCs, MPA significantly suppressed IFN-α production with IRF7 nuclear translocation and repressed the AKT activity. In addition, MPA inhibited IL-12 production with STAT4 expression in mDCs. We further identified that MPA had an inhibitory effect on SLE serum-induced IFN-α production by pDCs. CONCLUSIONS Our data suggest that MPA can interrupt the vicious pathogenic spiral of autoimmune disorders by regulating the function of DC subsets. This work unveiled a novel mechanism for the therapeutic ability of MMF against SLE.
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Affiliation(s)
- Minoru Shigesaka
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Tomoki Ito
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan.
| | - Muneo Inaba
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Kai Imai
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Hideki Yamanaka
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Yoshiko Azuma
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Akihiro Tanaka
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Hideki Amuro
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Tohru Nishizawa
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Yonsu Son
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Atsushi Satake
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Yoshio Ozaki
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
| | - Shosaku Nomura
- First Department of Internal Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan
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3
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Immunogenicity for antisense oligonucleotides: a risk-based assessment. Bioanalysis 2019; 11:1913-1916. [PMID: 31648527 DOI: 10.4155/bio-2019-0133] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Sowa M, Hiemann R, Schierack P, Reinhold D, Conrad K, Roggenbuck D. Next-Generation Autoantibody Testing by Combination of Screening and Confirmation-the CytoBead® Technology. Clin Rev Allergy Immunol 2017; 53:87-104. [PMID: 27368807 PMCID: PMC5502073 DOI: 10.1007/s12016-016-8574-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Occurrence of autoantibodies (autoAbs) is a hallmark of autoimmune diseases, and the analysis thereof is an essential part in the diagnosis of organ-specific autoimmune and systemic autoimmune rheumatic diseases (SARD), especially connective tissue diseases (CTDs). Due to the appearance of autoAb profiles in SARD patients and the complexity of the corresponding serological diagnosis, different diagnostic strategies have been suggested for appropriate autoAb testing. Thus, evolving assay techniques and the continuous discovery of novel autoantigens have greatly influenced the development of these strategies. Antinuclear antibody (ANA) analysis by indirect immunofluorescence (IIF) on tissue and later cellular substrates was one of the first tests introduced into clinical routine and is still an indispensable tool for CTD serology. Thus, screening for ANA by IIF is recommended to be followed by confirmatory testing of positive findings employing different assay techniques. Given the continuous growth in the demand for autoAb testing, IIF has been challenged as the standard method for ANA and other autoAb analyses due to lacking automation, standardization, modern data management, and human bias in IIF pattern interpretation. To address these limitations of autoAb testing, the CytoBead® technique has been introduced recently which enables automated interpretation of cell-based IIF and quantitative autoAb multiplexing by addressable microbead immunoassays in one reaction environment. Thus, autoAb screening and confirmatory testing can be combined for the first time. The present review discusses the history of autoAb assay techniques in this context and gives an overview and outlook of the recent progress in emerging technologies.
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Affiliation(s)
- Mandy Sowa
- GA Generic Assays GmbH, Dahlewitz, Berlin, Germany
| | - Rico Hiemann
- Institute of Biotechnology, Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Peter Schierack
- Institute of Biotechnology, Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Dirk Reinhold
- Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Karsten Conrad
- Institute of Immunology, Medical Faculty, Technical University Dresden, Dresden, Germany
| | - Dirk Roggenbuck
- GA Generic Assays GmbH, Dahlewitz, Berlin, Germany.
- Institute of Biotechnology, Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany.
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5
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Abstract
This brief review is focused on different methodologies available for detection of anti-dsDNA antibodies with respect to the best adequacy between biological results of laboratory and clinical significance. A large array of assays has been developed for the measurement of anti-dsDNA. New assays continually introduced have reflected not only technical innovations to avoid difficulties of some assays, but even more with hope to correlate better with systemic lupus erythematosus (SLE), particularly with its clinical course and exacerbations. Finally, with the development of micro arrays technology new insights into the pathophysiology of autoimmune disease processes should be revealed.
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Affiliation(s)
- A M Rouquette
- Laboratory of Hematology, Tenon Hospital, Pierre et Marie Curie University, Paris, France.
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López-Hoyos M, Ayerbe I, Martínez-Taboada VM, Bartolomé MJ, Blanco R, López-Escribano H, Peña M, Rodríguez-Valverde V. Letter to the Editor. Lupus 2016; 13:144-7. [PMID: 14995011 DOI: 10.1191/0961203304lu511xx] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Manson JJ, Isenberg DA. The origin and pathogenic consequences of anti-dsDNA antibodies in systemic lupus erythematosus. Expert Rev Clin Immunol 2014; 2:377-85. [DOI: 10.1586/1744666x.2.3.377] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Riboldi P, Gerosa M, Moroni G, Radice A, Allegri F, Sinico A, Tincani A, Meroni PL. Anti-DNA antibodies: a diagnostic and prognostic tool for systemic lupus erythematosus? Autoimmunity 2009; 38:39-45. [PMID: 15804704 DOI: 10.1080/08916930400022616] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The clinical impact of anti-DNA antibodies lies on their diagnostic power for systemic lupus erythematosus (SLE), being a formal classification criterion. In spite of such a disease association, low-avidity anti-DNA antibodies might also be part of the natural autoantibody repertoire. Their switch to pathogenic high-avidity autoantibodies is the result of the autoimmune process leading to SLE.Anti-DNA antibodies were shown to play a role in SLE pathogenesis and particularly in kidney damage. Accordingly, antibody titres might fluctuate in relation to disease activity, but their prognostic value for flares is still debated.Several methods for anti-DNA detection were described and there is evidence that the assays identify different antibodies with different prognostic value. The results of a multicenter study on four different routine tests for anti-dsDNA antibody detection showed that: (i) Farr assay displays the best diagnostic specificity/sensitivity for SLE, followed by Crithidia luciliae method (CLIFT), (ii) the new generation of solid phase assay (EliA) shows an increased sensibility versus the classical enzyme linked immune assay (ELISA) but a decreased specificity. Antibody titre detected by EliA and Farr assay correlated with disease activity. These findings would suggest that more than one assay should be useful for SLE diagnosis and monitoring.
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Affiliation(s)
- Piersandro Riboldi
- Allergy, Clinical Immunology and Rheumatology Unit, IRCCS Istituto Auxologico, Department of Internal Medicine, University of Milan, Italy
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Matsubara T, Aoki N, Hino S, Okajima T, Nadano D, Matsuda T. Serum and monoclonal immunoglobulin E antibodies from NC/Nga mice with severe atopic-like dermatitis recognize an auto-antigen, histone H3. Clin Exp Allergy 2009; 39:579-90. [PMID: 19226275 DOI: 10.1111/j.1365-2222.2008.03174.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND NC/Nga mice are known to show a spontaneous outbreak of atopic-like dermatitis accompanied by a marked elevation in serum IgE levels when reared in a conventional environment. The specific effects of such a strong serum IgE response on the development of the dermatitis and specific antigens recognized by the IgE antibodies are still uncertain. OBJECTIVE AND METHODS To characterize the IgE of NC/Nga mice, we established IgE-secreting hybridoma clones from spleen cells of NC/Nga mice spontaneously developing dermatitis and identified variable-region genes and specific antigens of the IgE monoclonal antibodies (mAbs). Serum polyclonal IgE, as well as IgG1 and IgG2a, specific for the identified antigen were also analysed. RESULTS Four IgE-producing hybridoma clones were established. Variable-region nucleotide sequences of the IgE mAbs showed that these clones did not necessarily share common germline gene segments (V, D or J) for each variable region, and several somatic mutations had occurred in the V gene segments. Through antigen screening, histone H3 was identified to be an auto-antigen recognized by three of the four IgE mAbs. Serum IgE as well as IgG1 specific for histone H3 were almost undetectable in 6-week-old mice, but rapidly increased by 10-12 weeks of age. This age-dependent increase in the serum anti-histone H3 IgE was roughly in parallel with the onset of dermatitis, and slightly preceding total IgE elevation. The serum-specific IgE level correlated well with a dermatitis-severity score of each mouse at 12-16 weeks of age, and weakly with the severity of ear erosion of each mouse over 28 weeks of age. Furthermore, immunologically detectable histone-H3 antigens were observed in skin tissue sections from the dermatitis sites. CONCLUSION In NC/Nga mice, anti-histone H3 auto-antibodies may contribute, at least in part, to the considerably elevated serum IgE and might play some roles in the development and exacerbation of dermatitis.
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Affiliation(s)
- T Matsubara
- Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
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10
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Abstract
IgG antibodies against dsDNA are involved in the pathogenesis of systemic lupus erythematosus (SLE) glomerulonephritis. In contrast, glomerulonephritis is rare in SLE patients with IgM antibodies against dsDNA. Therefore, a possible protective effect of IgM antibodies has been studied in more detail. In murine models of SLE, the lack of secreted IgM was associated with more severe glomerulonephritis. In more recent studies, the treatment of lupus-prone mice with a murine IgM monoclonal antibody against dsDNA prevented renal damage. Furthermore, the clearance of pathogenic immune complexes may be improved by IgM. Therefore, IgM antibodies against dsDNA are indeed protective and may be a new treatment modality of lupus nephritis in humans.
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11
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Herkel J, Kam N, Erez N, Mimran A, Heifetz A, Eisenstein M, Rotter V, Cohen IR. Monoclonal antibody to a DNA-binding domain of p53 mimics charge structure of DNA: anti-idiotypes to the anti-p53 antibody are anti-DNA. Eur J Immunol 2005; 34:3623-32. [PMID: 15495163 DOI: 10.1002/eji.200425371] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Antibodies to DNA are important markers of various autoimmune diseases and can be pathogenic; however, their generation is not understood. We previously reported that anti-DNA antibodies could be induced in mice by idiotypic immunization to PAb-421, an antibody to a DNA-binding domain of p53. We now report that two monoclonal antibodies of moderate affinity (K(D) asymptotically equal to 10(-7)), raised from PAb-421-immunized mice, specifically recognized both PAb-421 and DNA. These antibodies feature multiple arginine residues in the antigen-binding site, a unique characteristic of disease-associated anti-DNA antibodies; nevertheless, these anti-DNA antibodies show specific complementarity to PAb-421 by competing with p53 for PAb-421 binding and recognize defined oligonucleotides with a specificity similar to that of p53. To study the structural basis for the cross-recognition of PAb-421 and DNA by the anti-DNA antibodies, we constructed computer models (fine-tuned by protein-protein docking) of PAb-421 and one of the monoclonal anti-DNA antibodies. The modeled structures manifested structural complementarity. Most notably, the modeled structure of PAb-421 resembled the structure of DNA by the positions of negatively charged groups and aromatic side chains. Thus, a protein molecule may mimic the structure of DNA and the elusive generation of anti-DNA antibodies could be explained by idiotypic immunity to a DNA-binding protein, like p53.
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Affiliation(s)
- Johannes Herkel
- Department of Medicine, Johannes Gutenberg University, Mainz, Germany
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12
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Recent advances in understanding the clinical utility and underlying cause of antinucleosome (antichromatin) autoantibodies. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.cair.2004.04.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Ghirardello A, Doria A, Zampieri S, Tarricone E, Tozzoli R, Villalta D, Bizzaro N, Piccoli A, Gambari PF. Antinucleosome antibodies in SLE: a two-year follow-up study of 101 patients. J Autoimmun 2004; 22:235-40. [PMID: 15041044 DOI: 10.1016/j.jaut.2003.12.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2003] [Revised: 12/17/2003] [Accepted: 12/24/2003] [Indexed: 10/26/2022]
Abstract
We prospectively analyzed the diagnostic sensitivity and specificity as well as the clinical relevance of antinucleosome antibodies in SLE. One hundred and one consecutive SLE patients were followed for 3 years. Three serial serum samples from each patient were tested for antinucleosome antibodies by ELISA (optimum cut-off value 10 U/ml), and for anti-dsDNA antibody (by ELISA and IIF on Crithidia luciliae), and anti-dsDNA avidity (by Scatchard plot analysis). Sera from 100 healthy individuals (HI), 35 patients with systemic sclerosis (SSc), 30 with primary Sjögren's syndrome (SS), 20 with rheumatoid arthritis (RA) and 48 with infectious diseases (ID), were assayed as controls. SLE activity and damage were evaluated using the ECLAM score and the SLICC/ACR index. At baseline, antinucleosome antibodies were found in 87 patients with SLE (86.1%), in 8 patients with SSc (22.8%), in 2 HI (2%), and in 1 ID (2.1%). The sensitivity and specificity of antinucleosome testing for SLE were 86.1% and 95.3%, respectively. The prevalence of antinucleosome antibodies in SLE was significantly higher than that of anti-dsDNA antibodies, with a correlation between them. No relevant relationship was found between antinucleosome antibodies and disease features, including renal involvement, disease activity, and disease damage. During follow-up, no significant variation was observed in antinucleosome level, nor in anti-dsDNA antibody level or avidity. We conclude that antinucleosome antibodies are commonly found in SLE. Low antibody levels can be detected in SSc, whereas medium/high levels are highly specific for SLE. Their clinical relevance during the disease course and utility for monitoring the individual patient seem to be poor.
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Affiliation(s)
- A Ghirardello
- Department of Medical and Surgical Sciences, Division of Rheumatology, University of Padova, Via Giustiniani, 2, 35128 Padova, Italy
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14
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Abstract
It is over 40 years since anti-dsDNA antibodies were first described in patients with lupus. A wide variety of methods for detecting these immunoglobulins have been established. In this review, we consider the utility and practical problems that the main assays present. The clinical correlations between anti-dsDNA antibodies and clinical activity in patients with lupus is discussed.
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Affiliation(s)
- D Isenberg
- Centre for Rheumatology, The Middlesex Hospital, University College London Hospitals, London, UK
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15
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Abstract
Many authors have studied the links between levels of anti-dsDNA antibodies and disease activity in patients with SLE. Interpretation of these studies must take into account the facts that there are a range of possible assays for anti-dsDNA and a number of indices available for assessing disease activity. A recent study compared levels of various autoantibodies with organ specific disease activity assessed during the British Isles Lupus Assessment Group (BILAG) index. Anti-dsDNA and anti-heparan sulphate levels were more likely to be raised in patients with renal than non-renal disease. Some anti-DNA antibodies are actually anti-nucleosome antibodies, which lose DNA reactivity when purified under dissociating conditions. Patients with SLE have significantly increased levels of nucleosomes in their sera compared with healthy controls. In patients with SLE, reduced clearance of nucleosomes released from apoptotic cells may induce the formation of anti-nucleosome antibodies.
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Affiliation(s)
- A Rahman
- Centre for Rheumatology, Department of Medicine, University College London, London, UK.
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Björkman L, Reich CF, Pisetsky DS. The use of fluorometric assays to assess the immune response to DNA in murine systemic lupus erythematosus. Scand J Immunol 2003; 57:525-33. [PMID: 12791090 DOI: 10.1046/j.1365-3083.2003.01261.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Antibodies to DNA (anti-DNA) play an important role in the pathogenesis of systemic lupus erythematosus (SLE). In blood, these antibodies may exist in a free, unbound state or as part of complexes with DNA. Furthermore, circulating DNA may be either complexed or free. Because of the central role of these immunoreactants (anti-DNA and DNA) in the disease, monitoring of their levels could provide valuable information for both clinical and investigative purposes. In these studies, we have explored the use of a DNA-binding dye, PicoGreen, for the detection of circulating DNA, either total or immune complex bound. In addition, we have used this dye for Farr-type antibody assays. Using autoimmune MRL/lpr mice as a model, we have shown that, while the levels of free DNA in the plasma of these mice were comparable with those of normal BALB/c mice, the amounts in complexes precipitable by ammonium sulfate were significantly greater. Furthermore, we showed that Farr assays using PicoGreen reliably detect levels of free anti-DNA, with values correlated with anti-DNA levels by an enzyme-linked immunosorbent assay. Together, our results suggest that a fluorometric dye can accurately monitor DNA and anti-DNA antibody levels in SLE and may provide important information on immunopathogenesis.
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Affiliation(s)
- L Björkman
- Medical Research Service, Durham Veterans Administration Hospital and Division of Rheumatology, Duke University Medical Center, Durham, NC, USA
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17
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Abstract
The identification of circulating autoantibodies contributes to the correct diagnosis as well as to the follow-up of rheumatic diseases. Some autoantibodies are even included in diagnostic and classification criteria for these types of autoimmune diseases. There are several relatively specific screening and identification methods for the measurement of autoantibodies available. The type of assay crucially influences the diagnostic value of the parameters. In general, routine laboratories should prefer enzyme immunoassays (ELISA) using well characterized antigens, although ELISA tests tend to produce more false-positive and true weakly positive results, which reduce their positive predictive value. Therefore one should be aware that laboratory results can only be properly interpreted when there is a correlation with the clinical situation and when the limitations of the technologies used for autoantibody identification have been taken into consideration. A diagnostic algorithm consisting of screening and identification steps should be established by each laboratory in order to create a rational, evidence-based and cost-effective basis for the diagnosis of rheumatic diseases.
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Affiliation(s)
- A Griesmacher
- Institute of Laboratory Diagnostics, Kaiser-Franz-Josef-Hospital, Vienna, Austria.
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