Autoantibodies to DFS70/LEDGF are increased in alopecia areata patients

Clinical Significance of Antibodies to DFS70 in Immunoinflammatory Rheumatic Diseases

The relevance of the problem of immunoinflammatory rheumatic diseases (IIRD) for modern medicine is determined by their high prevalence in the population, the difficulty of early diagnosis, the rapid development of disability and poor life prognosis. Recent data on the significance of anti-DFS70 have opened up new possibilities for optimizing the step-by-step diagnosis of IIRD. The detection of these antibodies can help in the interpretation of a positive result for antinuclear antibodies (ANA) by indirect immunofluorescence assay on HEp-2 cells (IIFA-HEp-2) in the absence of autoantibodies specific for IIRD. Detection of anti-DFS70 in antinuclear factor (ANF) seropositive patients without clinical and/or serological markers characteristic of a certain disease from the IIRD group can be considered as a potential marker that excludes this group of diseases.

Clinical characteristics and immune profiles of patients with immune-mediated alopecia associated with COVID-19 vaccinations

BACKGROUND

The clinical characteristics and pathomechanism for immune-mediated alopecia following COVID-19 vaccinations are not clearly characterized.

OBJECTIVE

We investigated the causality and immune mechanism of COVID-19 vaccines-related alopecia areata (AA).

STUDY DESIGN

27 new-onset of AA patients after COVID-19 vaccinations and 106 vaccines-tolerant individuals were enrolled from multiple medical centers for analysis.

RESULTS

The antinuclear antibody, total IgE, granulysin, and PARC/CCL18 as well as peripheral eosinophil count were significantly elevated in the patients with COVID-19 vaccines-related AA compared with those in the tolerant individuals (P = 2.03 × 10-5-0.039). In vitro lymphocyte activation test revealed that granulysin, granzyme B, and IFN-γ released from the T cells of COVID-19 vaccines-related AA patients could be significantly increased by COVID-19 vaccine excipients (polyethylene glycol 2000 and polysorbate 80) or spike protein (P = 0.002-0.04).

CONCLUSIONS

Spike protein and excipients of COVID-19 vaccines could trigger T cell-mediated cytotoxicity, which contributes to the pathogenesis of immune-mediated alopecia associated with COVID-19 vaccines.

Anti-DFS70 antibodies are associated with atopic dermatitis and can cause misdiagnosis of connective tissue disease

BACKGROUND AND OBJECTIVES

Antinuclear antibodies (ANA) detected by HEp2 cell immunofluorescence staining are a characteristic finding in patients with connective tissue disease (CTD). However, even detection of highly elevated ANA is not conclusive for CTD and can result in misdiagnosis. Anti-DFS70 antibodies are ANA, which may also be highly elevated in people without CTD. Thus, we wanted to evaluate whether they could cause misdiagnosis of CTD. Since anti-DSF70 antibodies have been associated with atopic dermatitis (AD) in Japan, we wanted to investigate this association and its potential diagnostic relevance in Germany.

PATIENTS AND METHODS

We retrospectively analyzed data of 40 patients referred for first consultation on CTD and prospectively analyzed the prevalence of anti-DFS70 antibodies in 110 AD patients and 89 controls.

RESULTS

We could not confirm CTD in 75% of our referred patients, 26% of whom had already received systemic treatments. DFS70-typical fluorescence staining was detected in 35% and definitive anti-DFS70 antibodies in 12.5% of these patients. DFS70-typical fluorescence staining was detected in 22% of AD patients and anti-DFS70 antibodies in 10% (versus 5.6% and 0% in control patients, P < 0.001).

CONCLUSIONS

Anti-DFS70 antibodies are significantly associated with AD and could be responsible for misdiagnosis of CTD.

The Prevalence and Clinical Relevance of the DFS Immunofluorescence Staining Pattern in a Large ANA-Positive Cohort

Background

Although the dense fine speckled (DFS) immunofluorescence staining pattern has been studied by various researchers in recent years, its clinical associations remain unspecified. Thus, we performed a retrospective study in a non-selective population to explore the prevalence of this enigmatic antinuclear antibody (ANA) pattern and to determine its possible clinical associations with any identifiable pathology.

Methods

We retrieved the results of ANA testing ordered by various departments in 2019 to study the prevalence of DFS pattern. Demographic characteristics and clinical features of these participants were also collected from the electronic medical record system. Correlation analysis was made to study its clinical associations and a p-value < 0.05 was considered statistically significant.

Results

The prevalence of ANA positivity was 37.4% among 72,204 serum samples of which the median age was 44 (interquartile range: 31, 56) years old and 68.0% were women. The prevalence of the DFS staining pattern was 1.1% in the total population and accounted for 3.1% in the ANA-positive population. There were 97.6% of these cases displaying the DFS pattern with a low titer of ANA (≤1:320; starting serum dilution: 1:100). We found that this pattern correlated with several pathological conditions, such as skin disorders (25.1%), alopecia (4.6%), and obstetric complications (6.6%).

Conclusion

The presence of the DFS immunofluorescence staining pattern may accompany several pathological conditions and may be a signal of localized inflammation within certain organs or tissues, especially the skin.

Presence of autoantibodies in serum does not impact the occurrence of immune checkpoint inhibitor-induced hepatitis in a prospective cohort of cancer patients

Purpose

Immune checkpoint inhibitor (ICI)-induced hepatitis belongs to the frequently occurring immune-related adverse events (irAEs), particularly with the combination therapy involving ipilimumab and nivolumab. However, predisposing factors predicting the occurrence of ICI-induced hepatitis are barely known. We investigated the association of preexisting autoantibodies in the development of ICI-induced hepatitis in a prospective cohort of cancer patients.

Methods

Data from a prospective biomarker cohort comprising melanoma and non-small cell lung cancer (NSCLC) patients were used to analyze the incidence of ICI-induced hepatitis, putatively associated factors, and outcome.

Results

40 patients with melanoma and 91 patients with NSCLC received ICI between July 2016 and May 2019. 11 patients developed ICI-induced hepatitis (8.4%). Prior to treatment, 45.5% of patients in the hepatitis cohort and 43.8% of the control cohort showed elevated titers of autoantibodies commonly associated with autoimmune liver diseases (p = 0.82). We found two nominally significant associations between the occurrence of ICI-induced hepatitis and HLA alleles associated with autoimmune liver diseases among NSCLC patients. Of note, significantly more patients with ICI-induced hepatitis developed additional irAEs in other organs (p = 0.0001). Neither overall nor progression-free survival was affected in the hepatitis group.

Conclusion

We found nominally significant associations of ICI-induced hepatitis with two HLA alleles. ICI-induced hepatitis showed no correlation with liver-specific autoantibodies, but frequently co-occurred with irAEs affecting other organs. Unlike other irAEs, ICI-induced hepatitis is not associated with a better prognosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03870-6.

Anti - Dense Fıne Speckled (DFS) Antibody: its staınıng pattern in indirect immunofluorescence and its clinical relevance

BACKGROUND

Dense fine speckled (DFS) pattern defined by very intense, heterogeneous speckled staining of nucleoplasms of interphase HEp-2 cells and chromosomal areas of metaphase cells. The association of Anti-DFS70 and rheumatologic signs, symptoms, and diagnosis were evaluated.

METHODS

One-hundred-eight anti-DFS70 positives who consecutively admitted Rheumatology clinic between January-June 2020 were analyzed. The clinical and laboratory findings of positives for anti-DFS70 antibody were compared with those with DFS pattern ANA IFA staining rates. Also, anti-DFS70 positivity rates and their correlation with the DFS staining pattern were analyzed retrospectively in 1016 CTD patients.

RESULTS

The most common complaint was joint pain seen in 77(71.3%) and the most common laboratory abnormality was RF-positivity observed in 10/108(9.3%) who had anti-DFS70 positivity. The most common ANA staining pattern was DFS (72/108;66,7%); one-third had other than DFS. No statistical significance was found for the association of any of the rheumatological complaints and laboratory findings with the DFS70 staining pattern. ANA analysis was performed in a total of 964/1016(94.88%) CTD patients and 44 (4.56%) of these positive for anti-DFS70. The correlation coefficient showed good correlations between the DFS pattern staining and anti-DFS70 antibody positivity (r=+0.773, p<0.001).

CONCLUSIONS

Anti-DFS70-positives have a low rate of CTD. A low anti-DFS70 positivity rate was observed in patients with CTD. As such, it can be considered that anti-DFS70 does not predict CTD or even excludes it.

The antinuclear antibody dense fine speckled pattern and possible clinical associations: An indication of a proinflammatory microenvironment

BACKGROUND

Indirect immunofluorescence (IIF) is the most prevalent screening antinuclear antibody test for systemic autoimmune rheumatic disease (SARD). Certain IIF patterns have known antibody and disease associations, but the dense fine speckled (ANA-DFS) pattern has no confirmed clinical associations. Our objective was to determine the prevalence of SARD among a group of ANA-DFS positive individuals and to identify final diagnoses among non-SARD individuals in order to determine possible clinical associations with the ANA-DFS pattern.

METHODS

A retrospective study of 425 patients from a university health care system with a positive ANA-DFS pattern consecutively between August 2017 and September 2018. Sera samples underwent ANA testing by IIF on HEp-2 cell substrates (Euroimmun, Germany). Clinical information was retrieved from electronic health records and stored in a de-identified database.

RESULTS

The prevalence of SARD was 24%. Undetermined diagnosis (17%), skin disorders (12.1%), and fibromyalgia/chronic pain syndrome/chronic fatigue syndrome (11.8%) were the most common non-SARD diagnoses. Taking into account past medical history, the most common non-SARD were atopic disorders (21.2%), fibromyalgia/chronic pain syndrome/chronic fatigue syndrome (17.6%), and skin disorders (16.7%).

CONCLUSIONS

The ANA-DFS pattern may be indicative of an underlying antigen-antibody interaction that plays a role in either the initiation or propagation of immunologic reactions. DFS70/LEDGF is a transcription factor involved in cell survival and stress protection, and autoantibodies may inhibit its function. It is likely that there are other antibodies producing the ANA-DFS pattern besides anti-DFS70/LEDGF, and more research is necessary to identify additional antibody specificities. The ANA-DFS pattern may be an indicator of a proinflammatory microenvironment given the high frequency of symptomatic patients and disease processes with an immunologic basis (including SARD).

Cumulative visual impact of two coagulability disorders: A case report

Cumulative visual impact of two coagulability disorders were reviewed by presenting a case of a young female patient with a spontaneous abortion and two thromboembolic events in 8 years, whose visual function was severely affected. The particularities of her genetic constellation regarding the retinal circulation are also discussed. The patient developed a central retinal artery occlusion in the right eye during pregnancy in 2010, which led to an extended hematological workup that revealed presence of MTHFR C677T and MTHFR A1298C heterozygote mutations. The screening for myeloproliferative disorders showed JAK2 V617F gene mutation. Test results confirmed the diagnosis of thrombophilia and essential thrombocythemia and she was recommended permanent treatment with low molecular weight heparin, platelet antiaggregant, peripheral vasodilator and neuroprotectors. Despite the treatment, the patient developed central retinal vein occlusion in the fellow eye 8 years after the first thromboembolic event. The visual acuity for the right eye (0.9 logMAR) remained poor and the visual acuity for the left eye recovered completely (from 0.3 logMAR to 0 logMAR). However, new retinal artery or vein occlusions could occur in the future and there is also a risk of thrombosis in other areas, such as cerebral, pulmonary or renal, due to the general coagulability imbalance.

Targeting Wnt/β-Catenin Pathway for Developing Therapies for Hair Loss

Persistent hair loss is a major cause of psychological distress and compromised quality of life in millions of people worldwide. Remarkable progress has been made in understanding the molecular basis of hair loss and identifying valid intracellular targets for designing effective therapies for hair loss treatment. Whereas a variety of growth factors and signaling pathways have been implicated in hair cycling process, the activation of Wnt/β-catenin signaling plays a central role in hair follicle regeneration. Several plant-derived chemicals have been reported to promote hair growth by activating Wnt/β-catenin signaling in various in vitro and in vivo studies. This mini-review sheds light on the role of Wnt/β-catenin in promoting hair growth and the current progress in designing hair loss therapies by targeting this signaling pathway.

Establishment of an international autoantibody reference standard for human anti-DFS70 antibodies: proof-of-concept study for a novel Megapool strategy by pooling individual specific sera

Background

International autoantibody standards, traditionally based on material obtained from plasmapheresis of single subjects, represent individual immune response and may not comprehend the heterogeneity of the general population. The anti-DFS70 autoantibody yields a characteristic dense fine speckled (DFS) nuclear pattern on indirect immunofluorescence assay on HEp-2 cells (HEp-2 IFA) and speaks against autoimmunity. We propose a novel strategy for developing autoantibody reference standards, based on stepwise pooling of serum samples from hundreds of individuals with anti-DFS70 antibodies.

Methods

Within a 2-year period, serum samples were selected from routine HEp-2 IFA according to the following criteria: DFS HEp-2 IFA pattern at titer ≥1:640; anti-DFS70 reactivity in three analyte-specific tests (Western blot [WB], enzyme-linked immunosorbent assay [ELISA] and chemiluminescent immunoassay [CLIA]). Aliquots of individual samples were combined into progressively larger pools with stepwise validation of intermediary pools as for individual samples. Validated intermediary pools were merged into a final pool for lyophilization.

Results

A total of 741 validated samples yielded a 750 mL final pool that was lyophilized into thousands of 200 μL-aliquots. Reconstituted aliquots yielded the expected anti-DFS70 reactivity in ELISA, CLIA and WB, as well as high-titer DFS HEp-2 IFA pattern. The appropriate anti-DFS70 reactivity of the lyophilized pool was confirmed by seven international expert centers, using HEp-2 IFA, ELISA, WB and immunoprecipitation.

Conclusions

This proof-of-concept study provides an innovative and efficient strategy to build serum reference standards for autoantibody testing. The anti-DFS70 standard will integrate the panel of standards of Autoantibody Standardization Committee (ASC, www.autoab.org), contributing to education for proper assay validation and interpretation of the DFS pattern and other HEp-2 IFA patterns.

Recognition and Relevance of Anti-DFS70 Autoantibodies in Routine Antinuclear Autoantibodies Testing at a Community Hospital

Antinuclear autoantibodies (ANA) displaying a dense fine speckled pattern (DFS, ICAP AC-2) on HEp-2 cells are frequently observed in clinical laboratory referrals, often associated with anti-DFS70 specificity. Anti-DFS70 positive patients rarely develop systemic autoimmune rheumatic disease (SARD), especially in the absence of clinical evidence or additional anti-extractable nuclear antigen (ENA) antibodies, prompting suggestions that an isolated DFS70-specific ENA may be an exclusionary finding for SARD. In this study, the frequency and diagnostic significance of anti-DFS70 autoantibodies was investigated in a community hospital cohort of patients undergoing routine ANA testing. ANA screening was performed by HEp-20-10-based indirect immunofluorescence, followed by ENA profiling using a multiparametric line immunoassay (LIA). Of 6,511 patient samples tested for ANA in 2016, the DFS pattern was identified in 1,758 (27.0%), 720 (41.0%) of which were anti-DFS70 positive by LIA. Of these, 526 (73.1%) revealed isolated anti-DFS70 reactivity, while 194 (26.9%) showed additional ENA specificities. Among 1,038 anti-DFS70 negative or borderline samples, 778 (75.0%) were ENA profile negative, while the remaining 260 (25.0%) showed a varied presence of other ENA specificities. Chart reviews of patients with an isolated anti-DFS70 ANA affirmed that ANA-related SARD is rare in the absence of clinical evidence or other ENA specificities, there being no case thus far identified. Rheumatoid arthritis patients occasionally had an isolated anti-DFS70 ANA and were positive for rheumatoid factor and anti-cyclic citrullinated peptide antibodies. In conclusion, the recognition of a DFS ANA pattern using a mitotic-rich HEp-2 substrate, followed by confirmation of anti-DFS70 specificity should be a routine ANA testing service. Use of an expanded ENA profile and clinical correlation is necessary to affirm the "isolation" of anti-DFS70 as the cause of an ANA. Recognition of isolated anti-DFS70 ANA enables reassurance of patients that SARD is unlikely, thus avoiding referral for more extensive testing. The presence of significant elevations of other ENAs may reflect SARD and warrants close clinical correlation and follow-up.

Simultaneous Distinction of Monospecific and Mixed DFS70 Patterns During ANA Screening with a Novel HEp-2 ELITE/DFS70 Knockout Substrate

Systemic autoimmune connective tissue disorders are characterized by circulating antinuclear antibodies (ANA). Although there are several technologies available for ANA screening, indirect immunofluorescence (IIF) using Human epithelial cells-2 (HEp-2) substrate remains the primary and recommended method because of its superior sensitivity. HEp-2 substrates can detect a multitude of patterns resulting from autoantibody binding to various protein and nucleic acid autoantigens distributed throughout the nucleus and cytoplasm of the cells. The great diversity of monospecific and mixed patterns resulting from positive reactions on HEp-2 substrate also complicate the interpretation and accuracy of reporting. One specific example which received utmost attention recently is the dense fine speckled 70 (DFS70) pattern resulting from autoantibodies that specifically bind to a protein called lens epithelium derived growth factor (LEDGF). Lack of clear association with a specific systemic autoimmune disease and high prevalence in healthy populations have made accurate interpretation of DFS70 pattern important. Accurate distinction of DFS70 pattern from disease-associated patterns using conventional HEp-2 substrate is challenging. Moreover, frequent co-occurrence of DFS70 pattern along with disease-associated patterns such as homogeneous, speckled, and mixed homogeneous-speckled patterns complicate the IIF interpretation. The goal of this paper is to demonstrate the utility of a novel engineered HEp-2 IIF substrate that retains all advantages of conventional HEp-2 substrate while simultaneously providing the ability to distinguish DFS70 pattern with high confidence in both monospecific and mixed ANA positive examples. The new substrate is further able to unmask disease-associated ANA patterns previously concealed by DFS70 pattern.

[Antinuclear antibodies without connective tissue disease : Antibodies against LEDGF/DSF70]

Testing for antinuclear antibodies (ANA) by the indirect immunofluorescence test (IFT) is regarded as a fundamental serological screening method for diagnosing connective tissue diseases (CTD). In the case of a negative result exclusion of certain CTDs is indicated, especially systemic lupus erythematosus, and a positive ANA result is the starting point for further tests aimed at finding disease-specific autoantibodies. The recently discovered antibodies against lens epithelium-derived growth factor (LEDGF/DSF70) deviate from the normal interpretation pattern in ANA diagnostics. These antibodies give rise to a characteristic dense fine speckled (DSF) immunofluorescence pattern in IFT and target the ubiquitously expressed nuclear stress protector protein LEDGFp75. They can be detected, sometimes in high titers, not only in patients with diverse disorders of the skin or eyes and with neoplasms but also in persons with relatively mild or unspecific complaints and even in apparently healthy individuals; however, they are less frequent in CTD. These anti-LEDGF antibodies can be found in all age groups with a tendency to a higher prevalence in younger people and the frequency does not increase in advanced age. The vast majority of anti-LEDGF carriers are female. The CTDs with isolated anti-LEDGF antibodies, i. e. unaccompanied by autoantibodies typical for the respective CTD, are extremely rare. Detection of ANA exclusively with a DSF immunofluorescence pattern and confirmed by a specific anti-LEDGF binding assay, does not therefore indicate the presence of CTD but is indicative of exclusion of systemic lupus erythematosus, systemic sclerosis and an ANA-associated overlap syndrome, similar to a completely negative ANA result.

The Clinical Relevance of Anti-DFS70 Autoantibodies

Despite all the progress in the establishment of specific autoantibody assays, screening for antinuclear antibodies (ANA) by indirect immunofluorescence on HEp-2 cells for quality-oriented laboratory diagnosis of ANA associated rheumatic diseases (AARD) remains indispensable but is not without limitations. Recent data on the relevance of the dense fine speckled (DFS) pattern and anti-DFS70 antibodies disclosed novel possibilities to optimize the serological stepwise diagnostics of AARD. The DFS pattern on HEp-2 cells is well differentiated from the classic "homogeneous" ANA pattern associated with dsDNA antibodies. This is the most frequent pattern in high titer ANA-positive healthy persons. The most characteristic ANA specificity associated with DFS pattern is the anti-DFS70 antibody (synonym LEDGF antibody). The prevalence of anti-DFS70 antibodies in AARD patients is significantly lower compared with the prevalence in ANA-positive healthy persons. There is a negative association between anti-DFS70 antibodies and AARD, especially if no concomitant AARD-specific autoantibodies are found. Isolated anti-DFS70 antibodies are detectable in less than 1 % of AARD but are detectable in 2-22 % of healthy persons. In the presence of an isolated anti-DFS70 antibody, the posttest probability for AARD is reduced significantly. The significance of anti-DFS70 antibodies as a criterion that helps to exclude AARD is also confirmed by follow-up studies on anti-DFS70 antibodies of positive, healthy individuals, who did not develop any AARD during a 4 year observation period. Consequently, anti-DFS70 antibodies are valuable novel biomarkers for better interpretation of positive ANA in cases of negative AARD-associated autoantibodies and should be integrated in modified test algorithms to avoid unnecessary referrals and examinations of ANA-positive persons.

Analysis of DFS70 pattern and impact on ANA screening using a novel HEp-2 ELITE/DFS70 knockout substrate

Indirect immunofluorescence (IIF) using human epithelial cell (HEp-2) substrate is a widely used and the recommended method for screening of antinuclear antibodies (ANA). Dense fine speckled (DFS70) pattern on HEp-2 has been widely reported in various healthy and disease groups. Interpretation of DFS70 pattern can be challenging on a conventional HEp-2 substrate due to its similarity to some of the disease associated patterns. The high prevalence of DFS70 autoantibodies in normal population, lack of association with a particular disease group and a general negative association with systemic and ANA associated autoimmune rheumatic diseases (SARD/AARD) necessitates the confirmation of DFS70 pattern. Results using available commercial assays for confirmation of DFS70 autoantibodies do not always agree with IIF screening results further complicating the lab work flow and ANA algorithms. In this review, we discuss the prevalence of DFS70 antibodies and factors affecting the performance of IIF and DFS70 specific confirmatory assays. Factors that contribute to disagreement between DFS70 suspicion by IIF and confirmatory assays will also be discussed. In addition, we also describe a novel IIF HEp-2 substrate, and its positive impact on DFS70 reporting and ANA screening-confirmation algorithm.

Humoral and Cellular Autoreactivity to Epidermal Proteins in Atopic Dermatitis

Atopic dermatitis (AD), a chronic relapsing inflammatory disease of the skin, is an important public health concern affecting 10-20 % of children worldwide. The etiology and pathogenesis of AD involve the interplay of genetic and environmental factors, including abnormalities in skin integrity and a skewed immune system usually driven by a Th2 phenotype in childhood with a switch to Th1 in the chronic phase of disease. Children and adults with AD commonly have elevated IgE levels directed to multiple different antigens, including aeroallergens, food allergens, and microbial proteins. IgE targeting self-antigens from epidermal proteins have been detected in up to 91 % of patients, particularly in severe persistent AD. It has been suggested that the occurrence of autoreactivity develops in early childhood. However, it is not clear yet if autoreactive IgEs in patients with AD are pathogenic or just an epiphenomenon. The fact that these autoantibodies are associated with severity and are not present in other allergic or skin diseases favors the pathogenicity of IgE-mediated autoreactivity in AD. In this review, we evaluate the pathogenesis of AD and the emerging role of autoreactivity to various keratinocyte antigens involving both the humoral and cellular components of the immune system.

Confirmation of anti-DFS70 antibodies is needed in routine clinical samples with DFS staining pattern

Background

Recognition of nuclear dense fine speckled (DFS) pattern by indirect immunofluorescence (IIF) is not easy. Thus, confirming the presence of these antibodies might be needed. In this study, we aimed to determine the frequency of DFS pattern in our diagnostic laboratory and to investigate the presence of anti-DFS70 antibodies in samples showing DFS pattern by two commercially available research kits retrospectively.

Material and methods

Seventy-four sequential serum samples with DFS pattern on HEp2010 cell substrates by IIF were included in this study. The semiquantitative DFS70 ELISA Kit (MBL International Corporation, Woburn, UK) was used for detection of anti-DFS70 antibodies in these samples. Twenty selected samples were tested for the presence of anti-DFS70 antibodies using ANA Line Immunoassay (LIA) (Immco Diagnostics, New York, USA).

Results

Sixty-two (83.8%) of 74 serum samples were found positive with ELISA, when 15 U/ml was taken as a reference value. Among 18 samples that were found positive by ELISA, five were negative for anti-DFS70 antibodies by LIA, while 13 were found positive. The lowest ELISA result of the sample that was positive by LIA was found to be 45.3 U/ml. When 45.3 U/ml was considered as a reference value, 45 (60.8%) of 74 serum samples were positive by ELISA. Nineteen of 20 patients had no SARD, while one had systemic lupus erythematosus (SLE).

Conclusions

DFS pattern should be confirmed with an objective method such as ELISA, LIA, or IB. We think that confirmation tests for detection of anti-DFS70 antibodies should be included in diagnostic algorithms.

Specific chemoluminescence and immunoasdorption tests for anti-DFS70 antibodies avoid false positive results by indirect immunofluorescence

OBJECTIVE

To evaluate two new diagnostic methods for the identification of anti-DFS70 antibodies in samples showing a DFS70-staining pattern by indirect immunofluorescence (IIF).

METHODS

We studied 731 patients: 576 were collected consecutively among those that in the ANA test on HEp-2 cells had produced a DFS70 fluorescence pattern and 155 were a consecutive series of patients sent by referring physicians for routine ANA testing. As controls we studied 50 patients with autoimmune diseases and 120 patients with active infectious disease. All 731 sera were assayed for anti-DFS70 antibodies by a specific chemoluminescence assay (CLIA); 70 randomly selected IIF-positive sera and 35 samples from patients with autoimmune diseases were studied by inhibition tests using the HEp-2 Select method.

RESULTS

Assays performed with the CLIA-DFS70 method were positive in 30.4% of the samples presenting a DFS70 pattern by IIF, in 1.3% of the routine ANA sera, in 1.6% of the infectious sera and in none of the 50 autoimmune controls. However, as the IIF-DFS70 positive group included 106 patients with systemic autoimmune rheumatic diseases (SARD), 11 of which were DFS70 positive by CLIA, the prevalence of DFS70 antibodies in SARD was 7.5%. The ANA test performed after the use of HEp-2 Select showed an inhibition in 95.7% of the sera. No change in fluorescence intensity and pattern morphology between the native sera and the same sera tested with the solution containing the DFS70 antigen was observed in the 35 samples from patients with autoimmune diseases.

CONCLUSIONS

To avoid misinterpretation of ANA pattern and consequent diagnostic errors, confirmation of the DFS70-IIF pattern by CLIA or other specific methods is mandatory before reporting the presence of anti-DFS70 antibodies. The HEp-2 Select test in most cases eliminates the interference by anti-DFS70 antibodies and avoids the possible reporting of false positive results.

Thrombophilia Associated with Anti-DFS70 Autoantibodies

CONTEXT

Anti-DFS70 antibodies are the most frequent antinuclear antibodies (ANA) found in healthy individuals. We assessed the clinical significance of the presence of anti-DFS70 antibodies.

METHODS

We defined a group of patients (n = 421) with anti-DFS70 antibodies and a group of patients (n = 63) with a history of idiopathic arterial and/or venous thrombotic disease and/or obstetric complication (i.e. ≥ 3 miscarriages, fetal death or premature birth with eclampsia). Anti-DFS70 antibodies prevalence was also assessed in a cohort of 300 healthy blood donors.

RESULTS

The prevalence of thrombotic disease and/or obstetric complication in the 421 patients with anti-DFS70 antibodies was 13.1% (n = 55) and the prevalence of connective tissue disease was 19% (n = 80). Among the 63 patients with a history of thrombosis and/or obstetric complications, 7 (11.1%) had anti-DFS70 antibodies and among the latter, 5 had no common thrombophilic factor. In contrast, the prevalence of anti-DFS70 antibodies was of 3.0% (9 out of 300) in healthy donors. Finally, the Activated Partial Thromboplastin Time (aPTT) ratio of patients with a history of thrombosis and anti-DFS70 antibodies was lower than the aPTT ratio of other patients, suggesting that thrombotic patients with anti-DFS70 antibodies may have a hypercoagulable state.

CONCLUSION

We described here for the first time an immune procoagulant state involving anti-DFS70 antibodies.

The significance of autoantibodies to DFS70/LEDGFp75 in health and disease: integrating basic science with clinical understanding

Antinuclear autoantibodies (ANAs) displaying the nuclear dense fine speckled immunofluorescence (DFS-IIF) pattern in HEp-2 substrates are commonly observed in clinical laboratory referrals. They target the dense fine speckled autoantigen of 70 kD (DFS70), most commonly known as lens epithelium-derived growth factor p75 (LEDGFp75). Interesting features of these ANAs include their low frequency in patients with systemic autoimmune rheumatic diseases (SARD), elevated prevalence in apparently healthy individuals, IgG isotype, strong trend to occur as the only ANA specificity in serum, and occurrence in moderate to high titers. These autoantibodies have also been detected at varied frequencies in patients with diverse non-SARD inflammatory and malignant conditions such as atopic diseases, asthma, eye diseases, and prostate cancer. These observations have recently stimulated vigorous research on their clinical and biological significance. Some studies have suggested that they are natural, protective antibodies that could serve as biomarkers to exclude a SARD diagnosis. Other studies suggest that they might be pathogenic in certain contexts. The emerging role of DFS70/LEDGFp75 as a stress protein relevant to human acquired immunodeficiency syndrome, cancer, and inflammation also points to the possibility that these autoantibodies could be sensors of cellular stress and inflammation associated with environmental factors. In this comprehensive review, we integrate our current knowledge of the biology of DFS70/LEDGFp75 with the clinical understanding of its autoantibodies in the contexts of health and disease.

DFS70 antibodies – biomarkers for the exclusion of ANA-associated autoimmune rheumatic diseases

Despite the progress in the establishment of specific autoantibody assays, screening for antinuclear antibodies (ANA) by indirect immunofluorescence on HEp-2 cells for quality-oriented laboratory diagnosis of ANA associated rheumatic diseases (AARD) remains indispensable. Research results on the relevance of the dense fine speckled (DFS) pattern and DFS70 antibodies disclosed novel possibilities to optimize the serological stepwise diagnostics of AARD. The DFS pattern on HEp-2 cells is well differentiated from the classic “homogeneous” ANA pattern associated with dsDNA antibodies. In DFS pattern positive sera the most important detectable ANA specificity is the DFS70 antibody (synonym LEDGF antibody). This antibody is also the most frequent ANA specificity in ANA positive healthy persons. The prevalence of DFS70 antibodies in AARD patients is significantly lower compared with the prevalence in ANA-positive healthy individuals. There is a negative association between DFS70 antibodies and AARD, especially if no concomitant AARD-specific autoantibodies are found. Isolated DFS70 antibodies are detectable in <1% of AARD, but are detectable in 5%–11% of healthy individuals. In the presence of an isolated DFS70 antibody, the posttest probability for AARD is reduced significantly. DFS70 antibodies are valuable novel biomarkers for the improved interpretation of positive ANA but without detectable AARD associated autoantibodies and should be integrated in modified test algorithms to avoid unnecessary referrals and examinations of ANA-positive subjects.

Current concepts and future directions for the assessment of autoantibodies to cellular antigens referred to as anti-nuclear antibodies

The detection of autoantibodies that target intracellular antigens, commonly termed anti-nuclear antibodies (ANA), is a serological hallmark in the diagnosis of systemic autoimmune rheumatic diseases (SARD). Different methods are available for detection of ANA and all bearing their own advantages and limitations. Most laboratories use the indirect immunofluorescence (IIF) assay based on HEp-2 cell substrates. Due to the subjectivity of this diagnostic platform, automated digital reading systems have been developed during the last decade. In addition, solid phase immunoassays using well characterized antigens have gained widespread adoption in high throughput laboratories due to their ease of use and open automation. Despite all the advances in the field of ANA detection and its contribution to the diagnosis of SARD, significant challenges persist. This review provides a comprehensive overview of the current status on ANA testing including automated IIF reading systems and solid phase assays and suggests an approach to interpretation of results and discusses meeting the problems of assay standardization and other persistent challenges.

Serum level of macrophage migration inhibitory factor (MIF) in Egyptians with alopecia areata and its relation to the clinical severity of the disease

BACKGROUND

Alopecia areata (AA) is a common dermatological problem that manifests as sudden loss of hair without any inflammation or scarring. Various cytokines are implicated in the pathogenesis of this disease. Macrophage migration inhibitory factor (MIF) is located at an upstream position in the events leading to the possible dysregulated immuno-inflammatory responses, and the high level of this cytokine in AA may suggest a role of MIF in the pathogenesis of AA.

METHODS

This case-control study was carried out on 31 AA patients with different grades of severity and 15 apparently healthy subjects. Serum MIF level was measured by ELISA, and was correlated with the clinical severity of the disease using SALT (severity of alopecia tool) scoring system.

RESULTS

In this study, there was a significant elevation in serum MIF levels in AA patients in comparison with controls. There was also a positive correlation between MIF levels and clinical severity and disease duration.

CONCLUSION

MIF seems to have an essential role in the etiopathogenesis of AA. So, it is considered to be a promising target in the therapy of autoimmune diseases and as a future predictor of alopecia activity. Anti-MIF therapy might be added as one of the new biological treatments for AA.

Unfolded protein response in keratinocytes: impact on normal and abnormal keratinization

The unfolded protein response (UPR) is a signaling pathway from the endoplasmic reticulum (ER) to the nucleus that protects cells from stress caused by misfolded or unfolded proteins. As such, ER stress is an ongoing challenge for all cells, given the central biologic importance of secretion as part of normal physiologic functions. Mild UPR is activated by mild ER stress, which occurs under normal conditions. Abnormal UPR is activated by severe ER stress, which occurs under pathological conditions. Abnormal UPR activation is associated with a number of diseases, including diabetes mellitus and Alzheimer's disease. Within skin tissues, keratinocytes in the epidermis are especially dependent upon a mild UPR for normal differentiation in the course of their differentiation into secretory cells in the uppermost granular layers. Association between abnormal UPR activation and hereditary keratoses, including Darier's disease, keratosis linearis with ichthyosis congenita and keratoderma syndrome, erythrokeratoderma variabilis, and ichthyosis follicularis with atrichia and photophobia syndrome, have been elucidated recently. This review describes the UPR in normal and abnormal keratinization and discusses the regulation of abnormal UPR activation by chemical chaperones as a potential treatment for one of the hereditary keratoses.

Lens epithelium-derived growth factor deSumoylation by Sumo-specific protease-1 regulates its transcriptional activation of small heat shock protein and the cellular response

Lens epithelium-derived growth factor (LEDGF), a ubiquitously expressed nuclear protein, acts by interacting with DNA and protein and is involved in widely varying cellular functions. Despite its importance, the mechanism(s) that regulate naturally occurring LEDGF activity are unidentified. In the present study, we report that LEDGF is constitutively Sumoylated, and that the dynamical regulatory mechanism(s) (i.e. Sumoylation and deSumoylation) act as a molecular switch in modulating the DNA-binding and transcriptional activity of LEDGF with the functional consequences. Using bioinformatics analysis coupled with in vitro and in vivo Sumoylation assays, we found that lysine (K) 364 of LEDGF was Sumoylated, repressing its transcriptional activity. Conversely, mutation of K364 to arginine (R) or deSumoylation by small ubiquitin-like modifier (Sumo)-specific protease-1, a nuclear deSumoylase, enhanced the transactivation capacity of LEDGF and its cellular abundance. The enhancements were directly correlated with an increase in the DNA-binding activity and small heat shock protein transcription of LEDGF, whereas the process was reversed in cells overexpressing Sumo1. Interestingly, cells expressing Sumoylation-deficient pEGFP-K364R protein showed increased cellular survival compared to wild-type LEDGF protein. The findings provide insights into the regulation and regulatory functions of LEDGF in Sumoylation-dependent transcriptional control that may be essential for modifying the physiology of cells to maintain cellular homeostasis. These studies also provide new evidence of the important role of post-translational modification in controlling LEDGF function.

Development of an ELISA for detection of autoantibodies to nuclear matrix protein 2

OBJECTIVES

Autoantibodies characterizing certain forms of inflammatory myopathy, which are myositis-specific autoantibodies, are useful in the diagnosis and prediction of prognosis in DM/PM. This study aimed to identify a subset of DM patients who have anti-nuclear matrix protein 2 (anti-NXP-2) antibodies by using biotinylated recombinant proteins, and to clarify the clinical features of DM patients with these antibodies.

METHODS

Sera from 170 Japanese patients with CTDs including 106 with DM, 8 with PM, 21 with SLE, 20 with SSc, 15 with myositis overlap syndrome and 20 healthy controls were screened for anti-NXP-2 antibodies by our novel ELISAs. Positive sera were further examined by immunoprecipitation.

RESULTS

Sera from 6 of the 170 patients with CTDs were confirmed to be positive for anti-NXP-2 antibodies. These six positives were from female patients, with five of the six sera being from adult DM patients and only one of the six being from 1 of the 12 JDM patients. All these patients had myositis. None of the anti-NXP-2-positive patients had interstitial lung disease, but one patient was complicated with ovarian cancer.

CONCLUSION

Our newly developed ELISA is applicable for the measurement of anti-NXP-2 antibodies. The results show that anti-NXP-2 antibodies, which have been characterized in JDM, exist in adult DM patients. Further studies using large populations are necessary to elucidate the characteristic clinical features and the prognosis of patients with anti-NXP-2 antibodies, especially for adult patients.

Cyclosporin A induces the unfolded protein response in keratinocytes

Psoriasis vulgaris is a chronic inflammatory disorder of the skin, in which activation of keratinocytes and crosstalk between keratinocytes and T cells or dendritic cells are considered to be involved in the pathogenesis of psoriasis vulgaris. Cyclosporin (Cy) A, an immunomodulator, has been used for the treatment of psoriasis vulgaris, but the mechanism of its action on keratinocytes has not been well elucidated as its function on T cells is well known. Previous study indicated that the expression of the unfolded protein response (UPR) markers, GRP78/Bip and HRD1 were poorly expressed in psoriasis vulgaris. To investigate if the UPR in keratinocytes is involved in the pathogenesis of psoriasis vulgaris we assessed immunocytochemistry of normal human skin and psoriatic lesions, quantitative PCR of keratinocyte cell line (HaCaT) treated with TGFβ. Moreover, to elucidate how CyA effects on the UPR in keratinocytes, we set out quantitative PCR and western blotting, HaCaT and squamous cell carcinoma cell lines (HSC-1) treated with CyA and CyA analog, cyclosporin D. Furthermore, the siRNA-mediated knockdown effect of cyclophilin (Cyp) A, Cyp B and Cyp C on HaCaT cells were also examined. As a result, the UPR was downregulated in keratinocytes from psoriatic lesions, characterized by immunocytochemical staining of GRP78/Bip, CHOP/GADD153, HRD1 and C/EBPβ. TGFβ induced UPR markers in HaCaT cells. CyA treatment and siRNA-mediated knockdown of Cyp B induced the UPR in HaCaT cells or HSC-1 cells. Altogether, we demonstrate that in psoriasis vulgaris CyA or reduction in Cyp B by RNA interference might induce the UPR in keratinocytes.

Epidermal growth factor receptor tyrosine kinase inhibitors induce CCL2 and CCL5 via reduction in IL-1R2 in keratinocytes

Epidermal growth factor receptor tyrosine kinase (EGFR-TK) is a transducer of mitogenic signals, and is involved in the pathogenesis and progression of a number of cancers, including non-small cell lung cancer (NSCLC). Gefitinib is an EGFR-TK inhibitor that is clinically used to treat NSCLC; however, this drug frequently causes adverse effects, including skin eruptions. The mechanism underlying these skin reactions is elusive, although it is assumed that they are caused by the inhibition of EGFR-TK signalling in epidermal and adnexal cells. In this article, we demonstrate by immunocytochemistry that the skin lesions of patients treated with oral gefitinib had higher expression of CCL2 and CCL5 compared to normal human epidermis. Further, PD153035, a gefitinib prototype, induced CCL2 and CCL5 mRNA and protein expression in HaCaT and HSC-1 keratinocyte cell lines with or without interleukin-1 (IL-1) treatment in vitro. PD153035 also reduced the levels of interleukin-1 receptor 2 (IL-1R2), an IL-1 decoy receptor. Moreover, we demonstrate that reduction in IL-1R2 by RNA interference increased IL-1-mediated CCL2 and CCL5 mRNA and protein expression. Taken together, our data strongly suggest that IL-1-mediated signalling is activated to induce the high expression of CCL2 and CCL5 via reduction in IL-1R2 in the skin lesions caused by gefitinib.

Overexpression of LEDGF/DFS70 induces IL-6 via p38 activation in HaCaT cells, similar to that seen in the psoriatic condition

Lens epithelium-derived growth factor (LEDGF)/dense fine speckles 70  kDa protein (DFS70) is a transcription cofactor that enhances growth and is overexpressed in various cancers. In the epidermis, LEDGF/DFS70 localizes to the nucleus of keratinocytes (KCs) in the basal layers and to the cytoplasm of cells in the upper layers. However, the biological and pathological relevance of LEDGF/DFS70 in the epidermis is virtually unknown. Compared with normal epidermis, we detected strong nuclear staining of LEDGF/DFS70 in both the spinous and basal layers of the epidermis of psoriatic skin. To investigate the roles of LEDGF/DFS70 in the epidermis of psoriatic skin, we generated HaCaT cells that constitutively express enhanced green fluorescence protein (EGFP)-LEDGF (EGFP-LEDGF-HaCaT) or EGFP alone (EGFP-HaCaT) as a control. EGFP-LEDGF-HaCaT cells had increased expression of IL-6, which was attenuated by LEDGF-specific RNA interference and the p38-specific inhibitors SB-239063 and SB-203580. Furthermore, EGFP-LEDGF-HaCaT cells had increased expression of S100A7 and S100A9 and decreased expression of filaggrin. These findings are compatible with the expression pattern in psoriatic tissues. Taken together, these results strongly suggest that ectopic expression of LEDGF/DFS70 in KCs could be involved in the pathology of psoriasis vulgaris.

[Clinical significance of dense fine speckled pattern in anti-nuclear antibody test using indirect immunofluorescence method]

BACKGROUND

Dense fine speckled (DFS) pattern in antinuclear antibody (ANA) test using indirect immunofluorescence method became to be known recently and it is detected in patients with various chronic inflammatory diseases as well as in healthy individuals. We investigated the relation between DFS pattern and various diseases.

METHODS

ANA tests by indirect immunofluorescence method using HEp-2 cell line slide (Kallestad; Bio-Rad, USA) were performed in 2,654 patients for screening of systemic autoimmune diseases. The frequencies of ANA and DFS positivity were analyzed according to sex, age, clinical department and disease.

RESULTS

ANA was positive in 13.3% (352/2,654) of the total patients, and the frequency of DFS pattern was observed in 3.8% (101/2,654) of the total patients and in 28.7% (101/352) of the patients with ANA positivity. Higher frequency of DFS positivity was observed in patients referred from Departments of Rheumatology and Nephrology, but there was no difference in the frequencies of DFS positivity among the patients with ANA positivity. The frequency of DFS pattern was higher in seborrheic dermatitis (14.3%), herpes zoster (11.1%), rheumatoid arthritis (16.9%), systemic lupus erythematosus (15.4%) and Sjogren syndrome (14.3%).

CONCLUSIONS

The DFS pattern is a frequent finding (about 28% of ANA positivity) in ANA test using indirect immunofluorescence method. Relatively high frequency of DFS pattern was observed in autoimmune diseases, contrary to the previous observations that DFS pattern is not related with autoimmune diseases. Further studies including the confirmation tests of anti-DFS70 are needed for the identification of relation between DFS pattern and particular diseases.

The unfolded protein response is activated in differentiating epidermal keratinocytes

The unfolded protein response (UPR), which is induced by stress to the endoplasmic reticulum (ER), is involved in the functional alteration of certain cells, such as the differentiation of B cells to plasma cells. The aim of this study is to determine whether the UPR is activated during epidermal keratinocyte (KC) differentiation. Here, we show that the expression of the UPR-induced proteins Bip/GRP78 and HRD1 was increased in cells in the supra-basal layers of normal human epidermis that contain KCs undergoing differentiation as well as in skin-equivalent cultured KCs. However, Bip/GRP78 and HRD1 were poorly expressed in proliferating KCs in squamous cell carcinoma and psoriasis vulgaris tissues. The epidermal growth factor receptor tyrosine kinase inhibitor, PD153035, which induces KC differentiation, upregulated UPR-induced marker mRNAs and proteins. Furthermore, microarray analyses and quantitative PCR revealed that ER stress-inducing reagents, tunicamycin (TU), thapsigargin, and brefeldin A, altered the expression of genes essential for human epidermal KC differentiation, including C/EBPbeta, KLF4, and ABCA12 in vitro. However, ABCA12 and KLF4 mRNA did not increase with TU treatment after siRNA-mediated knockdown of XBP-1. Taken together, our findings strongly suggest that the UPR is activated during normal epidermal KC differentiation and induces C/EBPbeta, KLF4, and ABCA12 mRNAs.

High concomitance of disease marker autoantibodies in anti-DFS70/LEDGF autoantibody-positive patients with autoimmune rheumatic disease

Autoantibodies against dense fine speckles 70 (DFS70) are found in 10% of healthy individuals, but only in a tiny population of patients with autoimmune rheumatic disease. The antibody may thus be a marker of autoimmune rheumatic disease negativity. To investigate this possibility, we examined the presence of various disease-marker autoantibodies in anti-DFS70 antibody-positive patients with autoimmune rheumatic disease. Serum samples from 500 patients with various types of autoimmune rheumatic disease were examined for anti-DFS70 antibodies by indirect immunofluorescence and immunoblotting. Various disease-marker autoantibodies were measured by enzyme-linked immunosorbent assay. Twenty-two patients were positive for anti-DFS70 antibodies. Eighteen patients also had disease-marker autoantibodies including anti-double stranded DNA, anti-cardiolipin, anti-SS-A, or other antibodies. In one patient with Sjögren syndrome and two patients with dermatomyositis, no disease-marker antibodies were found; however, one patient with dermatomyositis had a concomitant anti-cytoplasmic antibody. All seven systemic lupus erythematosus patients fulfilled the classification criteria for this disease even if anti-nuclear antibody-positive findings were excluded. One patient with morphea had high-titer anti-single stranded DNA antibody. According to this and previous studies, patients with only anti-DFS70 antibody are rarely diagnosed as having autoimmune rheumatic disease. Recognizing dense fine speckle patterns in anti-nuclear antibodies tests is, thus, very important for analysis of laboratory results in rheumatology clinics.

Lymphocytes, neuropeptides, and genes involved in alopecia areata

Many lessons in autoimmunity - particularly relating to the role of immune privilege and the interplay between genetics and neuroimmunology - can be learned from the study of alopecia areata, the most common cause of inflammation-induced hair loss. Alopecia areata is now understood to represent an organ-restricted, T cell-mediated autoimmune disease of hair follicles. Disease induction is associated with collapse of hair follicle immune privilege in both humans and in animal models. Here, the role of HLA associations, other immunogenetic factors, and neuroendocrine parameters in alopecia areata pathogenesis are reviewed. This instructive and clinically significant model disease deserves more widespread interest in the immunology community.

LEDGF/DFS70, a major autoantigen of atopic dermatitis, is a component of keratohyalin granules

Lens epithelium-derived growth factor/dense fine speckles 70 kDa protein (LEDGF/DFS70) is a transcriptional cofactor, a transcriptional activator, survival factor, and HIV-1 transporter. It is also a major autoantigen in patients with atopic dermatitis (AD), because autoantibodies to this protein are found in approximately 30% of AD patients. To better understand the role of autoantibodies and autoantigens in the pathogenesis of AD, we examined the distribution of LEDGF/DFS70 in the epidermis of normal human skin by light and electron microscopic immunocytochemistry. Increased amounts of LEDGF/DFS70 were located in the nuclei of cells in the basal layer, whereas the cytoplasm of cells in the granular layer stained for LEDGF/DFS70 by light microscopy. Using immunoelectron microscopy, we observed the accumulation of LEDGF/DFS70 in keratohyalin granules (KGs) in the cytoplasm of cells in the granular layer. In addition, Ig heavy chain-binding protein/glucose-regulated protein, 78-kDa (Bip/GRP78), a stress sensing protein in the endoplasmic reticulum, colocalized with LEDGF/DFS70 in the KGs. These results suggest that LEDGF/DFS70 is predominantly located in the nucleus of the basal epidermal cells and translocates into the cytoplasm during differentiation. Once in the cytoplasm, LEDGF/DFS70 accumulates in the KGs in the granular layer. Finally, LEDGF/DFS70, a "nuclear" autoantigen in AD, may play a functional role in the KGs.

HLA-associated production of anti-DFS70/LEDGF autoantibodies and systemic autoimmune disease

Autoantibodies against DFS70/LEDGF, which is also known as an important partner of HIV-1 integrase, are found in 10% of healthy Japanese people, but in only approximately 2% of patients with systemic autoimmune disease (SAD). We wished to characterize the association of HLA class II alleles with the presence of autoantibodies against this molecule. MHC class II genes (DR, DQ, and DP alleles) were analyzed by the polymerase chain reaction-sequence specific primer method in 24 individuals with anti-DFS70 antibodies. The frequencies of HLA-DRB1*0410, -DQB1*0402, and -DPB1*0301 were increased in anti-DFS70 Ab-positive patients, while HLA-DQB1*0302 was decreased compared to Japanese controls. All anti-DFS70 Ab-positive individuals expressed at least one HLA-DQB1 allele with an aspartic acid at residue 57. The immunogenetic background of Japanese individuals with anti-DFS70 antibodies differs from that of patients with SAD. HLA class II genes influence the production of anti-DFS70 antibodies among individuals with various clinical manifestations.

Transcriptional co-activator p75 binds and tethers the Myc-interacting protein JPO2 to chromatin

Transcriptional co-activator p75 is implicated in human cancer, autoimmunity and replication of human immunodeficiency virus type 1 (HIV-1) as a dominant integrase-interacting protein. Although characterized as chromatin associated, the normal biological role(s) of p75 remains fairly unclear. To gain insight into p75 function, we have characterized its cellular binding partners and report that JPO2, a recently identified Myc-binding protein, associates with p75 in vitro and in vivo. The pseudo HEAT repeat analogous topology (PHAT) domain of p75, which mediates its interaction with integrase, also mediates the interaction with JPO2, and recombinant integrase protein competes with JPO2 protein for binding to p75 in vitro. JPO2 binds p75 through a 61-residue (amino acids 58-119) region that is distinct from its Myc-interacting domain. In cells, JPO2 and p75 co-localize throughout the cell cycle, and both proteins concentrate on condensed chromosomes during mitosis. Strikingly, the association of JPO2 with chromatin strictly depends upon p75, similar to that of ectopically expressed integrase. Also similar to its effect on integrase, p75 stabilizes intracellular steady-state levels of JPO2 protein. Our results suggest a role for p75 in the Myc regulatory network, and indicate that p75 is a general adaptor protein tethering divergent factors to chromatin through its versatile integrase-binding domain.

DNA Binding Domains and Nuclear Localization Signal of LEDGF: Contribution of two Helix-Turn-Helix (HTH)-like Domains and a Stretch of 58 Amino Acids of the N-terminal to the Trans-activation Potential of LEDGF

Lens epithelium derived growth factor (LEDGF), a nuclear protein, plays a role in regulating the transcription of stress-associated genes such as heat shock proteins by binding to consensus core DNA sequences nAGGn or nGAAn or their repeats, and in doing so helps to provide cyto-protection. However, additional information is required to identify the specific structural features of LEDGF involved in gene transcription. Here we have investigated the functional domains activating and repressing DNA-binding modules, by using a DNA binding assay and trans-activation experiments performed by analyzing proteins prepared from deletion constructs. The results disclosed the DNA-binding domain of N-terminal LEDGF mapped between amino acid residues 5 and 62, a 58 amino acid residue stretch PWWP domain which binds to stress response elements (STRE; A/TGGGGA/T). C-terminal LEDGF contains activation domains, an extensive loop-region (aa 418-530) with two helix-turn-helix (HTH)-like domains, and binds to a heat shock element (HSE; nGAAn). A trans-activation assay using Hsp27 promoter revealed that both HTH domains contribute in a cooperative manner to the trans-activation potential of LEDGF. Interestingly, removal of N-terminal LEDGF (aa 1-187) significantly enhances the gene activation potential of C-terminal LEDGF (aa 199-530); thus the N-terminal domain (aa 5-62), exhibits auto-transcriptional repression activity. It appears that this domain is involved in stabilizing the LEDGF-DNA binding complex. Collectively, our results demonstrate that LEDGF contains three DNA-binding domains, which regulate gene expression depending on cellular microenvironment and thus modify the physiology of cells to maintain cellular homeostasis.

Evaluation of the profile of alopecia areata and the prevalence of thyroid function test abnormalities and serum autoantibodies in Iranian patients

BACKGROUND

The study aimed at evaluating the prevalence of thyroid function abnormalities in patients with alopecia areata (AA) and its association with other autoimmune diseases and various autoimmune antibodies.

METHOD

We retrospectively analyzed medical records of 123 patients with AA. The main site of involvement, pattern, and extent of alopecia as well as presence of the similar disease in first-degree family members and serologic status of patients were recorded.

RESULTS

Participating in the study were 57 males and 66 females (6 to 59 years old). In the majority of patients (69.9%) the disease was manifested in the first two decades of life. Patients with family members having alopecia were recorded in 24.4%. Thyroid function abnormalities were found in 8.9% of patients. Positive autoimmune antibodies were associated with AA in 51.4% of patients with no significant association between the severity and duration of disease and presence of these antibodies.

CONCLUSION

The incidence of positive auto-immune antibodies in Iranian patients is higher than previous reports. Concerning the female:male ratio, thyroid function tests and the prevalence of alopecia in first-degree relatives, our results are compatible with previous data obtained from different ethnic populations. Previous reports documented that a greater severity and longer duration of AA were seen in the early onset forms; however our result are relatively different which could be explained by differences in genetic factors.

Anti-p80 coilin autoantibodies react with a conserved epitope and are associated with anti-DFS70/LEDGF autoantibodies

p80 coilin is a nuclear autoantigen that strongly accumulates in Cajal bodies (CB) and is considered a marker for CBs. No clear clinical features have been associated with anti-p80 autoantibodies, and the epitopes recognized by these antibodies are entirely unknown. We determined the epitope specificity for 34 anti-p80 coilin-positive sera from Japanese patients to better understand its clinical significance. Western blotting and immunoprecipitation analysis revealed that the autoepitope of p80 coilin was restricted to a single region encompassing amino acid residues 421-576 from the C-terminus of p80 coilin. Additionally, sera from 30 of 34 (88%) patients with anti-p80 coilin antibody titers were also positive for anti-DFS70/LEDGF antibody. This autoantibody is sometimes found in patients with some allergic diseases but rarely in patients with connective tissue disease (CTD). Other similar characteristics between these two autoantibodies were also noted. In contrast, few anti-p80 coilin positive patients were positive for CTD-marker antibodies, such as anti-Sm, anti-dsDNA, and anti-SS-A. We conclude that the presence of anti-p80 coilin autoantibodies is not associated with any particular clinical syndromes nor is it diagnostic of any conditions.

Autoantigenicity of DFS70 is restricted to the conformational epitope of C-terminal alpha-helical domain

Autoantibodies against DFS70 (Dense Fine Speckles 70) are found in 30% of Japanese atopic dermatitis patients, and less frequently in patients with other diseases. We have recently reported that they are also seen in 11% of hospital workers, but in only approximately 2% of patients with systemic rheumatic disease. In this study, in order to investigate the possible pathological role of anti-DFS70 antibodies, fine epitope mapping was carried out using 93 anti-DFS70 autoantibody-positive sera. Immunoblotting using overlapping peptides failed to reveal major linear epitopes. Western blotting using various truncated proteins showed a strikingly uniform epitope distribution on a suspected tertiary structure expressed by DFS70(349-435). Some sera showed reactivity only in an immunoprecipitation assay using an in vitro translated DFS70. Circular dichroism analysis revealed that DFS(349-435) contains an approximately 40% alpha-helical conformation, while an overlapping, non-antigenic peptide is composed of random coiled structures. The skewed single major epitope enabled us to establish a highly quantitative ELISA for the epitope region. Antibody titers showed no significant differences between the diseased group and healthy individuals. We propose that anti-DFS70 antibody may be a natural autoantibody, which might modify or reflect the inflammatory process of various disorders.