Low diagnostic and predictive value of anti-dsDNA antibodies in unselected patients with recent onset of rheumatic symptoms: results from a long-term follow-up Scandinavian multicentre study

Longitudinal study of patients with discrepant results in CLIFT and a solid-phase dsDNA antibody assay: does a gold standard dsDNA assay exist?

OBJECTIVE

Antidouble-stranded DNA (dsDNA) antibodies are essential for diagnosis and follow-up of systemic lupus erythematous (SLE). To ensure the best diagnostic approach, most healthcare laboratories opt for a combination of highly sensitive methods, such as solid-phase immunoassays, and highly specific methods, such as the Crithidia luciliae indirect immunofluorescence test (CLIFT). Even so, discordant results are common, thus hindering the diagnostic process. Therefore, this study aimed to characterise a cohort of patients with discrepant results for a dsDNA fluorescence enzyme immunoassay (FEIA) and CLIFT during 2016-2018 and to follow patients up until December 2021.

METHODS

We performed an observational, longitudinal and retrospective study on 417 samples from 257 patients who had been referred for suspected connective tissue diseases or followed up after diagnosis. All of them were positive for antinuclear antibodies (ANAs) using an indirect immunofluorescence assay (IFA) on Hep-2 cells, the entry criterion in our laboratory, and positive for FEIA dsDNA. Samples were then tested with CLIFT according to our routine protocol, which includes CLIFT testing after FEIA dsDNA results ≥10 UI/ml. After the assessment of data quality, the final analysis was based on 222 patients.

RESULTS

Eighty-three patients (37.4%) had positive results in both tests and met the diagnostic criteria for SLE. However, 139 patients (62.6%) had discrepant results (FEIA+, CLIFT-). Of these, 58 patients (41.7%) had a diagnosis of SLE, with 47 (33.8%) having been previously diagnosed and under treatment. The remaining 11 patients (7.9%) had a new diagnosis of SLE, which was made up within 4 years of the initial screening. A total of 81 of the 139 patients (57.5%) with discrepant results did not meet lupus criteria during the follow-up period.

CONCLUSIONS

The study showed that CLIFT could be negative in both treated and newly diagnosed SLE, thus underlining the importance of follow-up of dsDNA-positive results using solid-phase tests. Therefore, quantitative tests such as FEIA could add value to the diagnosis and management of patients with suspected SLE.

Anti-dsDNA Testing Specificity for Systemic Lupus Erythematosus: A Systematic Review

BACKGROUND

Autoantibody specificity in autoimmune diseases is variable due to each patient's individual spectrum of autoantibodies and the inherent differences between detection methods and tests. Since false-positive results have downstream consequences, we conducted a comprehensive assessment of anti-double stranded DNA (anti-dsDNA) specificity from published studies of systemic lupus erythematosus (SLE).

METHODS

A systematic review (MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Database of Abstracts of Reviews of Effects) identified cross-sectional or case-control studies published January 2004 to August 2019, reporting anti-dsDNA test accuracy data in SLE. Study quality was assessed using Quality Assessment Tool for Diagnostic Accuracy Studies, version 2. A meta-analysis was conducted to estimate specificity by test method or named test where feasible.

RESULTS

Thirty studies were included covering 43 different tests. The Crithidia luciliae indirect immunofluorescence test (CLIFT) and fluorescence enzyme immunoassay methods are likely to be ≥ 90% specific (Euroimmun 97.8% (95% CI 96.2%-98.7%) 4 studies; EliA 94.7% (95% CI 91.7%-96.7%), 6 studies; CLIFT 98.7% (95% CI 96.7%-99.5%), 8 studies/7 tests]. For other test methods, specificity was not fully demonstrated to be ≥ 90% and/or the control group included healthy patients possibly overestimating specificity. More studies are required for NOVA Lite [96.0% (95% CI 87.2%-98.9%), 5 studies], chemiluminescence immunoassays [92.3% (95% CI 83.6%-96.6%), 6 studies/4 tests], multiplex immunoassays [89.3% (95% CI 86.1%-91.8%), 4 studies/2 tests], and Farr fluorescent immunoassays (no estimate, 2 studies). Specificity data reported for Farr radioimmunoassays [93.8% (95% CI 85.4-97.5%), 11 studies, 9 tests] and enzyme-linked immunosorbent assays [93.4% (95% CI 89.9%-95.7%), 15 studies/16 tests] lacked consistency.

CONCLUSION

Anti-dsDNA testing shows considerable variation in test specificity, with potential impact on the management of SLE patients. This review may help laboratory specialists and clinicians choose and interpret the appropriate anti-dsDNA test for their setting.

Comparative analysis of three methods in anti-dsDNA antibodies detection: implications for Systemic Lupus Erythematosus diagnosis

The evaluation of anti-dsDNA antibodies represents one of the essential diagnostic and prognostic marker features in patients affected by Systemic Lupus Erythematosus (SLE). In this study, we have compared immunoblotting (IB) with Crithidia luciliae indirect immunofluorescence test (CLIFT) and chemiluminescent immunoassay (CLIA) in 91 patients referred to our hospital for anti-dsDNA antibodies detection. The concordance and correlation measured by Cohen's kappa and Spearman's coefficient respectively was significant between CLIFT and CLIA (0.70; 0,7404, P < .0001) and among CLIA and IB (0.79; 0,5377, P < 0,0001) and lower between CLIFT and IB (0.55; 0,4373, P  <0,0001). Among the 46 IB-positive samples, 14 were positive for either CLIA or CLIFT. It is noteworthy that 11 out of these 14 samples had the final diagnosis of SLE. Thirteen out of fourteen samples were also positive for anti-nucleosome antibodies as measured concomitantly in immunoblotting. While our observations are based on a limited number of samples and will have to be confirmed in a bigger cohort, they underline the contribution of immunoblotting as an additional assay in defining the anti-dsDNA antibody profile in association with other well-established methods such as CLIA and CLIFT.

Comparisons of Anti-dsDNA Antibody Detection Methods by Chemiluminescent Immunoassay and Enzyme-Linked Immunosorbent Assay in Systemic Lupus Erythematosus

This study aimed to compare the test results of anti-double-stranded DNA (anti-dsDNA) antibodies obtained using chemiluminescent immunoassay (CIA) and enzyme-linked immunosorbent assay (ELISA), and investigate predictors of inconsistent results. This retrospective study included 502 patients who underwent CIA and ELISA to determine their anti-dsDNA antibody values within a year. We compared the diagnostic power for SLE, disease activity, and predictive power for lupus nephritis (LN). A multivariate analysis was performed to determine the predictors of inconsistencies. CIA and ELISA were moderately correlated in terms of their consistency (Cronbach’s α = 0.571), and yielded comparably favorable results in terms of SLE diagnostic power and SLE disease activity. However, if the patient had LN, CIA displayed higher predictive power than ELISA (0.620 vs. 0.555, p = 0.026). Compared with the CIA/ELISA double-positive group, the inconsistent group had lower anti-C1q circulating immune complexes (CIC) antibody values (OR: 0.42, 95% CI: 0.18–0.94, p = 0.036), and lower SLEDAI scores (≥4) (OR: 0.33, 95% CI: 0.14–0.79, p = 0.013). Anti-dsDNA antibody detection with CIA exhibited higher predictability for diagnosing LN than did ELISA. In the event of inconsistencies between anti-dsDNA methods, SLE disease activity and CIC test values should be considered simultaneously.

Update and clinical management of anti-DNA auto-antibodies

Anti-deoxyribonucleic acid (DNA) antibodies in the clinical laboratory are intimately linked to the diagnosis and monitoring of systemic lupus erythematosus (SLE); however, the characteristics of the analytical methods and the properties of the antibodies themselves are heterogeneous. To review the definition and properties of anti-double-stranded anti-DNA (anti-dsDNA) antibodies, the adequacy of analytical methods, and the clinical requirements for this biomarker. Through PubMed we searched the existing literature with the terms anti-dsDNA, editorial, review, guideline, meta-analysis and SLE. The last search, anti-dsDNA and SLE restricted to the last two years. Information was expanded through related articles and those published in official state bodies related to anti-dsDNA and SLE. Clinical laboratory methods for anti-dsDNA analysis and their characteristics are analyze. The clinical utility of anti-dsDNA in its diagnostic, clinical association and follow-up aspects of SLE is reviewed. There is wide variability in analytical methods and deficits in standardization persist. They are part of the current SLE classification criteria and are used as markers in the follow-up of the disease. Their diagnostic usefulness improves when they are determined in antinuclear antibody (ANA)-positive patients. In follow-up, quantification is of interest, preferably with the same analytical method (given the deficits in standardization).

Urine β-2-glycoprotein 1 as a biomarker for diagnosis of systemic lupus erythematosus

OBJECTIVE

The need for a biomarker with robust sensitivity and specificity in diagnosing systemic lupus erythematosus (SLE) remains unmet. Compared with blood samples, urine samples are more easily collected; thus, we aimed to identify such a biomarker based on urinary proteomics which could distinguish patients with SLE from healthy controls (HCs).

METHODS

Urine samples were collected from 76 SLE patients who visited rheumatology clinic in 2019 at Asan medical center and from 25 HCs. Urine proteins were analyzed using sequential windowed acquisition of all theoretical fragment ion spectra-mass spectrometry, and the candidate marker was confirmed by enzyme-linked immunosorbent assay (ELISA). Receiver operating characteristic curve analysis was used to determine the diagnostic value of the candidate biomarker.

RESULTS

Of 1157 proteins quantified, 153 were differentially expressed in urine samples from HCs. Among them were previously known markers including α-1-acid glycoprotein 1, α-2-HS-glycoprotein, ceruloplasmin, and prostaglandin-H2 D-isomerase. Moreover, the amount of β-2 glycoprotein (APOH) was increased in the urine of patients with SLE. The ELISA results also showed the level of urine APOH was higher in patients with SLE than in HCs and patients with rheumatoid arthritis. Moreover, the level was not different between SLE patients with and without nephritis. The urine APOH had an area under the curve value of 0.946 at a cut-off value of 228.53 ng/mg (sensitivity 91.5%, specificity 92.0%) for the diagnosis of SLE.

CONCLUSION

The results indicate that the urine APOH level can be an appropriate screening tool in a clinical setting when SLE is suspected.

Anti-double Stranded DNA Antibodies: Origin, Pathogenicity, and Targeted Therapies

Systemic lupus erythematosus (SLE) is characterized by high-titer serological autoantibodies, including antibodies that bind to double-stranded DNA (dsDNA). The origin, specificity, and pathogenicity of anti-dsDNA antibodies have been studied from a wider perspective. These autoantibodies have been suggested to contribute to multiple end-organ injuries, especially to lupus nephritis, in patients with SLE. Moreover, serum levels of anti-DNA antibodies fluctuate with disease activity in patients with SLE. By directly binding to self-antigens or indirectly forming immune complexes, anti-dsDNA antibodies can accumulate in the glomerular and tubular basement membrane. These autoantibodies can also trigger the complement cascade, penetrate into living cells, modulate gene expression, and even induce profibrotic phenotypes of renal cells. In addition, the expression of suppressor of cytokine signaling 1 is reduced by anti-DNA antibodies simultaneously with upregulation of profibrotic genes. Anti-dsDNA antibodies may even participate in the pathogenesis of SLE by catalyzing hydrolysis of certain DNA molecules or peptides in cells. Recently, anti-dsDNA antibodies have been explored in greater depth as a therapeutic target in the management of SLE. A substantial amount of data indicates that blockade of pathogenic anti-dsDNA antibodies can prevent or even reverse organ damage in murine models of SLE. This review focuses on the recent research advances regarding the origin, specificity, classification, and pathogenicity of anti-dsDNA antibodies and highlights the emerging therapies associated with them.

Preclinical and early systemic lupus erythematosus

The challenge of early diagnosis and treatment is a timely issue in the management of systemic lupus erythematosus (SLE), as autoimmunity starts earlier than its clinical manifestations. Hence, growing efforts for stratification of patients according to the individual risk of developing specific clinical manifestations and/or predicting a better response to a given treatment have led to the proposal of several biomarkers, which require validation for use in clinical practice. In this viewpoint, we aim at distinguishing and discussing the features and the approach to asymptomatic immunological abnormalities potentially heralding the development of SLE, defined as preclinical lupus, and clinical manifestations consistent with SLE not yet fulfilling classification criteria, defined as early lupus. In case of preclinical SLE, careful surveillance using available screening tools is paramount, while patients with early lupus deserve an appropriate and timely diagnosis and, consequently, a proper treatment including hydroxychloroquine as the anchor drug.

Antinuclear Antibody-Negative Systemic Lupus Erythematosus in an International Inception Cohort

OBJECTIVE

The spectrum of antinuclear antibodies (ANAs) is changing to include both nuclear staining as well as cytoplasmic and mitotic cell patterns (CMPs) and accordingly a change is occurring in terminology to anticellular antibodies. This study examined the prevalence of indirect immunofluorescence (IIF) anticellular antibody staining using the Systemic Lupus International Collaborating Clinics inception cohort.

METHODS

Anticellular antibodies were detected by IIF on HEp-2000 substrate using the baseline serum. Three serologic subsets were examined: ANA positive (presence of either nuclear or mixed nuclear/CMP staining), anticellular antibody negative (absence of any intracellular staining), and isolated CMP staining. The odds of being anticellular antibody negative versus ANA or isolated CMP positive was assessed by multivariable analysis.

RESULTS

A total of 1,137 patients were included; 1,049 (92.3%) were ANA positive, 71 (6.2%) were anticellular antibody negative, and 17 (1.5%) had an isolated CMP. The isolated CMP-positive group did not differ from the ANA-positive or anticellular antibody-negative groups in clinical, demographic, or serologic features. Patients who were older (odds ratio [OR] 1.02 [95% confidence interval (95% CI) 1.00, 1.04]), of white race/ethnicity (OR 3.53 [95% CI 1.77, 7.03]), or receiving high-dose glucocorticoids at or prior to enrollment (OR 2.39 [95% CI 1.39, 4.12]) were more likely to be anticellular antibody negative. Patients on immunosuppressants (OR 0.35 [95% CI 0.19, 0.64]) or with anti-SSA/Ro 60 (OR 0.41 [95% CI 0.23, 0.74]) or anti-U1 RNP (OR 0.43 [95% CI 0.20, 0.93]) were less likely to be anticellular antibody negative.

CONCLUSION

In newly diagnosed systemic lupus erythematosus, 6.2% of patients were anticellular antibody negative, and 1.5% had an isolated CMP. The prevalence of anticellular antibody-negative systemic lupus erythematosus will likely decrease as emerging nomenclature guidelines recommend that non-nuclear patterns should also be reported as a positive ANA.

Systemic Lupus Erythematosus: Definitions, Contexts, Conflicts, Enigmas

Systemic lupus erythematosus (SLE) is an inadequately defined syndrome. Etiology and pathogenesis remain largely unknown. SLE is on the other hand a seminal syndrome that has challenged immunologists, biologists, genetics, and clinicians to solve its nature. The syndrome is characterized by multiple, etiologically unlinked manifestations. Unexpectedly, they seem to occur in different stochastically linked clusters, although single gene defects may promote a smaller spectrum of symptoms/criteria typical for SLE. There is no known inner coherence of parameters (criteria) making up the disease. These parameters are, nevertheless, implemented in The American College of Rheumatology (ACR) and The Systemic Lupus Collaborating Clinics (SLICC) criteria to classify SLE. Still, SLE is an abstraction since the ACR or SLICC criteria allow us to define hundreds of different clinical SLE phenotypes. This is a major point of the present discussion and uses "The anti-dsDNA antibody" as an example related to the problematic search for biomarkers for SLE. The following discussion will show how problematic this is: the disease is defined through non-coherent classification criteria, its complexity is recognized and accepted, its pathogenesis is plural and poorly understood. Therapy is focused on dominant symptoms or organ manifestations, and not on the syndrome itself. From basic scientific evidences, we can add substantial amount of data that are not sufficiently considered in clinical medicine, which may change the paradigms linked to what "The Anti-DNA antibody" is-and is not-in context of the imperfectly defined syndrome SLE.

Autoantibodies against Modified Histone Peptides in SLE Patients Are Associated with Disease Activity and Lupus Nephritis

Persistent exposure of the immune system to death cell debris leads to autoantibodies against chromatin in patients with systemic lupus erythematosus (SLE). Deposition of anti-chromatin/chromatin complexes can instigate inflammation in multiple organs including the kidney. Previously we identified specific cell death-associated histone modifications as targets of autoantibodies in SLE. In this study we addressed, in a large cohort of SLE patients and controls, the question whether plasma reactivities with specific histone peptides associated with serology and clinical features. Plasma from SLE patients with and without lupus nephritis, disease controls, and healthy controls, were tested in ELISA with histone H4 peptide acetylated at lysines 8, 12 and 16 (H4p^ac), H2B peptide acetylated at lysine 12 (H2Bp^ac), H3 peptide trimethylated at lysine 27 (H3p^me), and their unmodified equivalents. SLE patients displayed a higher reactivity with the modified equivalent of each peptide. Reactivity with H4p^ac showed both a high sensitivity (89%) and specificity (91%) for SLE, while H2Bp^ac exhibited a high specificity (96%) but lower sensitivity (69%). Reactivity with H3p^me appeared not specific for SLE. Anti-H4p^ac and anti-H2Bp^ac reactivity demonstrated a high correlation with disease activity. Moreover, patients reacting with multiple modified histone peptides exhibited higher SLEDAI and lower C3 levels. SLE patients with renal involvement showed higher reactivity with H2B/H2Bp^ac and a more pronounced reactivity with the modified equivalent of H3p^me and H2Bp^ac. In conclusion, reactivity with H4p^ac and H2Bp^ac is specific for SLE patients and correlates with disease activity, whereas reactivity with H2Bp^ac is in particular associated with lupus nephritis.

Cutaneous characteristics and association with antinuclear antibodies in 402 patients with different subtypes of lupus erythematosus

BACKGROUND

Lupus erythematosus (LE) is an autoimmune disease characterized by a heterogeneous spectrum of skin manifestations and organ affection, and is frequently associated with serum autoantibodies, which mostly remain positive through the course of the disease. The classification of LE is still a controversial topic.

OBJECTIVES

To examine the prevalence and long-term course of autoantibodies in patients with cutaneous LE (CLE) and/or systemic LE (SLE) treated in the outpatient clinic for connective tissue diseases of the department of Dermatology in Bochum, Germany.

METHODS

Four hundred and two patients with LE were evaluated for antinuclear antibodies at a whole of 1572 time points. The prevalence as well as the long-term positivity of antinuclear antibodies and their correlation with the various subtypes of disease was examined.

RESULTS

Antinuclear antibody (ANA) testing and anti-ds-DNA antibodies were not only more prevalent in SLE patients (as expected from the ACR criteria for diagnosis of SLE, P < 0.0001), but also have had a more consistent course in the long-term evaluation (P = 0.0001 and P = 0.0111 respectively). Subacute cutaneous LE (SCLE) was associated with ANA (P = 0.0075), anti-Ro (P < 0.0001) and anti-La (P < 0.0001) antibodies, showing also higher consistency rates for these antibodies than discoid LE (DLE, P = 0.049, P = 0.004, P = 0.0004). Our data from 100 patients with LE tumidus (LET) support its perception as a distinct subtype of LE, not correlating with systemic disease or antinuclear antibodies (P < 0.0001). Anti-U1-ribonucleoprotein antibodies correlated with CLE in SLE patients (P = 0.0237), whereas non-LE-specific antinuclear antibodies were a rare, inconsistent autoimmune epiphenomenon in patients with SLE.

CONCLUSION

Long-term analysis of antinuclear antibodies has shown significant differences in various clinical subtypes of LE, confirming the actual classification of the disease. A serial evaluation of antinuclear antibodies may support the classification of disease in LE patients with overlapping clinical features.

Advances in the diagnosis and classification of systemic lupus erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is the prototype of systemic autoimmune diseases. Patients with SLE display a wide spectrum of clinical and serological findings that can mislead and delay the diagnosis. Diagnostic criteria have not been developed yet, whereas several sets of classification criteria are available; however, none of them has 100% sensitivity and 100% specificity, i.e. the hallmark of diagnostic criteria. Nevertheless, classification criteria are often misused as diagnostic criteria, which may affect earliness of diagnosis and lead to more misdiagnosed cases. Areas covered: In this review, we compare old and new classification criteria, discussing their application and pinpointing their limitations in the management of patients. Moreover, we will focus on current and novel biomarkers for SLE diagnosis, highlighting their predictive value and applicability in clinical practice. Expert commentary: SLE diagnosis still represents a challenge, remaining largely based on a clinical judgment. Besides SLE diagnosis, even its classification is still challenging to date. Indeed, although classification of SLE seems to be achieved more frequently with the 2012 SLICC criteria than with the previous 1997 ACR criteria, this last-updated 2012 set might be improved. Notably, diagnostic and classification criteria should be applied to any subject in the world, and consequently they should include immunological variables validated in different populations, which is still an unmet need.

The assessment of serum-mediated phagocytosis of necrotic material by polymorphonuclear leukocytes to diagnose and predict the clinical features of systemic lupus erythematosus: an observational longitudinal study

BACKGROUND

Serum-mediated phagocytosis of antibody- and complement-opsonized necrotic cell material (NCM) by polymorphonuclear leukocytes can be quantified by using a flow cytometry-based assay. The phagocytosis of necrotic cell material (PNC) assay parallels the well-known lupus erythematosus cell test. In this study, we aimed to investigate the diagnostic accuracy of the assay and the relationship with clinical manifestations and disease activity in systemic lupus erythematosus (SLE).

METHODS

The diagnostic accuracy for SLE diagnosis of the PNC assay was studied by cross-sectional assessment of blood samples from 148 healthy control subjects and a multicenter rheumatic group (MRG) of 529 patients with different rheumatic symptoms. A cohort of 69 patients with an established SLE diagnosis (SLE cohort) underwent longitudinal clinical and laboratory follow-up for analysis of the temporal relationships between PNC positivity and specific clinical manifestations.

RESULTS

In 35 of 529 MRG patients, 13 of whom had SLE, the PNC assay result was positive. Combined positivity of the PNC assay and anti-double-stranded DNA antibodies increased specificity and positive predictive value for SLE diagnosis to 0.99 and 0.67, respectively. In the longitudinal study, 42 of 69 SLE cohort patients had positive results in the PNC assay at least once. PNC assay positivity was associated with current hematological manifestations and could predict mucocutaneous manifestations. When combined with hypocomplementemia, PNC positivity preceded increased Systemic Lupus Erythematosus Disease Activity Index 2000 score, glomerulonephritis, and alopecia.

CONCLUSIONS

Serum-mediated PNC by polymorphonuclear leukocytes is commonly but not exclusively seen in patients with SLE. The PNC assay may be used in follow-up of patients with SLE and, especially in combination with other routinely assessed laboratory tests, may help to predict flares and different clinical manifestations, including glomerulonephritis. Our results encourage further development of the PNC assay as a complementary laboratory tool in management of patients with SLE.

Autoantibodies in SLE: Specificities, Isotypes and Receptors

Systemic Lupus Erythematosus (SLE) is characterized by a wide spectrum of auto-antibodies which recognize several cellular components. The production of these self-reactive antibodies fluctuates during the course of the disease and the involvement of different antibody-secreting cell populations are considered highly relevant for the disease pathogenesis. These cells are developed and stimulated through different ways leading to the secretion of a variety of isotypes, affinities and idiotypes. Each of them has a particular mechanism of action binding to a specific antigen and recognized by distinct receptors. The effector responses triggered lead to a chronic tissue inflammation. DsDNA autoantibodies are the most studied as well as the first in being characterized for its pathogenic role in Lupus nephritis. However, others are of growing interest since they have been associated with other organ-specific damage, such as anti-NMDAR antibodies in neuropsychiatric clinical manifestations or anti-β2GP1 antibodies in vascular symptomatology. In this review, we describe the different auto-antibodies reported to be involved in SLE. How autoantibody isotypes and affinity-binding to their antigen might result in different pathogenic responses is also discussed.

Anti-dsDNA Antibodies are one of the many autoantibodies in systemic lupus erythematosus

Anti-dsDNA antibodies are the most studied antibodies of the lupus-related autoantibodies. The dogma is that these are the most important autoantibodies in systemic lupus erythematosus. In this review, evidence is presented to show that these antibodies (as measured by modern clinical laboratories) are not the most important autoantibodies in the diagnosis of systemic lupus erythematosus, and are of limited value in clinical correlation and in predicting disease flares. In addition, they are not likely to be the initiating autoantibodies in lupus nephritis. Thus, several pervasively held beliefs on anti-dsDNA antibodies are not valid. We suggest that anti-dsDNA antibodies should be considered as just one of the many autoantibodies associated with systemic lupus erythematosus.

The anti-DNA antibody: origin and impact, dogmas and controversies

The inclusion of 'the anti-DNA antibody' by the ACR and the Systemic Lupus International Collaborating Clinics (SLICC) as a criterion for systemic lupus erythematosus does not convey the diverse origins of these antibodies, whether their production is transient or persistent (which is heavily influenced by the nature of the inducing antigens), the specificities exerted by these antibodies or their clinical impact-or lack thereof. A substantial amount of data not considered in clinical medicine could be added from basic immunology evidence, which could change the paradigms linked to what 'the anti-DNA antibody' is, in a pathogenic, classification or diagnostic context.

Evaluation of epratuzumab as a biologic therapy in systemic lupus erythematosus

B cells play a key role in the pathogenesis of systemic lupus erythematosus. Some of the current biologic therapies target B cells or B-cell activating factors. Epratuzumab is a humanized monoclonal antibody, which targets CD22 on B cells. This review focuses on the safety and efficacy of epratuzumab in systemic lupus erythematosus based on the information from various published clinical trials and presentations at international meetings. Epratuzumab acts as a B-cell modulator through inhibition of B-cell receptor signaling. It has been shown to be efficacious in open-label and Phase I and Phase II randomized controlled trials. The drug has steroid-sparing properties and treatment is associated with significant improvements in Health Related Quality of Life and its safety profile is comparable to placebo.

Clinical phenotype associations with various types of anti-dsDNA antibodies in patients with recent onset of rheumatic symptoms. Results from a multicentre observational study

Despite anti-dsDNA antibodies constitute a wide range of specificities, they are considered as the hallmark for systemic lupus erythematosus (SLE).