Identification Of Novel Autoantibodies Research Articles

Sleep and neuroimmunology: a narrative review.

Numerous neuroimmunological disorders present with sleep-related symptoms. The identification of novel autoantibodies introduces new clinical categories in autoimmune diseases of the central nervous system and generates interest in the dynamic interaction between sleep and the immune system. In this review, the complex relationship among sleep, immune regulation, and neuroimmunological disorders was examined with emphasis on the vital role of sleep in modulating immune function and its influence on these conditions, This relationship emphasizes the importance of assessments and management of sleep quality in the treatment approaches for neuroimmunological disorders.

A Glimpse into Humoral Response and Related Therapeutic Approaches of Takayasu's Arteritis.

Takayasu's arteritis (TAK) manifests as an insidiously progressive and debilitating form of granulomatous inflammation including the aorta and its major branches. The precise etiology of TAK remains elusive, with current understanding suggesting an autoimmune origin primarily driven by T cells. Notably, a growing body of evidence bears testimony to the widespread effects of B cells on disease pathogenesis and progression. Distinct alterations in peripheral B cell subsets have been described in individuals with TAK. Advancements in technology have facilitated the identification of novel autoantibodies in TAK. Moreover, emerging data suggest that dysregulated signaling cascades downstream of B cell receptor families, including interactions with innate pattern recognition receptors such as toll-like receptors, as well as co-stimulatory molecules like CD40, CD80 and CD86, may result in the selection and proliferation of autoreactive B cell clones in TAK. Additionally, ectopic lymphoid neogenesis within the aortic wall of TAK patients exhibits functional characteristics. In recent decades, therapeutic interventions targeting B cells, notably utilizing the anti-CD20 monoclonal antibody rituximab, have demonstrated efficacy in TAK. Despite the importance of the humoral immune response, a systematic understanding of how autoreactive B cells contribute to the pathogenic process is still lacking. This review provides a comprehensive overview of the biological significance of B cell-mediated autoimmunity in TAK pathogenesis, as well as insights into therapeutic strategies targeting the humoral response. Furthermore, it examines the roles of T-helper and T follicular helper cells in humoral immunity and their potential contributions to disease mechanisms. We believe that further identification of the pathogenic role of autoimmune B cells and the underlying regulation system will lead to deeper personalized management of TAK patients. We believe that further elucidation of the pathogenic role of autoimmune B cells and the underlying regulatory mechanisms holds promise for the development of personalized approaches to managing TAK patients.

An unbiased approach of individual tissue-specific autoantibody identification using Immunoprecipitation coupled to Mass-Spectrometry (IP-MS)

Abstract Background and aim Autoreactive antibodies have gained increasing recognition in autoimmune diseases of the central nervous system (CNS) serving as disease drivers and / or biomarkers. Identification of novel autoantibodies therefore is crucial to optimize diagnostic work and therapy of these diseases as well as understanding their pathogenesis. Hence, we aimed to develop an unbiased strategy to identify patients’ individual main autoantibodies directed against brain epitopes. Methods We used murine tissue-based assays to screen patients’ sera and cerebrospinal fluids (CSFs) for autoreactive IgGs with known and unknown antibody targets. IgGs from autoreactive patients’ samples were coupled to magnetic beads and used as a bait to pull down potential targets from homogenized brain tissue of wildtype mice. After precipitation and several washes to reduce unspecific binding, beads were subjected to on-bead tryptic digestion followed by mass spectrometry based proteomic analyses using liquid chromatography tandem mass-spectrometry (LC-MS/MS). For antibody targets identification the fold change enrichment compared to a negative control or to all other pulldown samples, as well as the protein abundance was used. Antibody target validation was done via recombinant expression of the target protein in HEK-293 cells and neutralization with the respective antigen in tissue-based immunofluorescence assays. Results As proof of principle, we were able to identify Grin1 Caspr2, Trim46 and Nf-h [MOU1] as main targets of patients’ sera or CSF with autoimmune encephalopathy. All four antigens showed highest enrichment and/or highest protein abundance in the respective samples and have been confirmed in cell-based assays. In addition, we identified one novel anti-neuronal antibody target in serum and CSF of a patient showing a speckled staining of the granular cerebellar layer. Preabsorbance of the serum and CSF with the recombinant protein fully neutralized the signal of the tissue-based immunofluorescence. Conclusions Our IP-MS approach is suitable to identify the main autoantibody targets in patients’ serum and CSF within murine CNS tissue thereby providing an unbiased and scalable technique allowing for tissue-specific autoantibody determination.

Myopathy in systemic sclerosis.

Systemic sclerosis associated myopathy (SSc-AM) is a complex, heterogenous disease that is associated with poor outcomes. SSc-AM lacks a clear definition, and continues to be poorly recognized. The purpose of this review is to provide a contemporary overview of the clinical, serological and pathophysiologic findings in SSc-AM to guide optimal recognition and management of this challenging disease manifestation. There have been several advances in diagnostic techniques to facilitate characterization of SSc-AM, including muscle MRI, in which findings were correlated to distinct histopathologic categories of muscle involvement in SSc, histopathologic findings of prominent fibrosis or inflammation on biopsy, and the identification of novel autoantibodies associated with SSc-AM, which may be associated with distinct clinical phenotypes. In one of the largest studies to date, 17% of a well phenotyped SSc cohort were found to have myopathy, which was an independent risk of death, even after adjusting for potential confounders, further highlighting the importance of timely recognistion and management of SSc-AM. There is increasing recognition of the importance of SSc-AM. Novel diagnostic tools provide the opportunity for more detailed insights into pathophysiologic mechanisms, which may facilitate the development of a rigorous consensus definition of SSc-AM.

Determination of autoantibody repertoire in the mouse model of viral myocarditis and in patients with non-ischemic cardiomyopathy by PhIP-Seq

Abstract Various infectious and non-infectious agents can cause myocarditis that may lead to cardiomyopathy with viruses being the most common suspects. Mechanistically, autoantibodies have been demonstrated for various antigens, in animal models and dilated cardiomyopathy patients, but their role continues to be enigmatic. First, by using the Coxsackievirus B3 (CVB3) infection model in A/J mice, we applied PhIP-Seq, a high-throughput platform to evaluate antibodies for various antigens. The data revealed the identification of antibodies to 32 antigens that were not previously reported. By investigating the biological significance of a few select antigens, we noted that cytochrome c oxidase assembly factor 4 homolog (COA4)-reactive antibodies were generated only in mice infected with CVB3 but not in influenza-infected animals proving virus specificity for antibody reactivity to COA4. Further immunogenicity studies revealed that animals immunized with COA4 did not develop myocarditis, nor was the T cell response generated, implying that COA4 is unlikely to act as a bonafide autoantigen. Alternatively, the COA4-reactive antibodies may represent biomarkers of viral myocarditis. Second, using the PhIP-Seq platform, we investigated the antibody profiles of human sera obtained from 25 age-matched non-ischemic cardiomyopathy patients and healthy controls. The analysis revealed significantly elevated levels of antibodies to 33 antigens, and the detection of the major candidates is being analyzed by ELISA as a secondary assay. Overall, our data suggest that the PhIP-Seq allows us to comprehensively analyze antibody repertoires that may lead to the identification of novel autoantibodies or their use as biomarkers. This work was supported in part by the institutional funds from the University of Nebraska-Lincoln (J.R.), the Transformational Grant 18TPA34170206 from the American Heart Association (J.R.), and the National Institutes of Health grants R01 HL114669 (J.R), R01 GM136724 (H.B.L.).

Anti-Carbamylated Protein Antibody Test Accuracy In Some Iraqi Patients With Rheumatoid Arthritis

Background: Rheumatoid arthritis is a persistent, immune-mediated disorder that causes pain, edema, and inflammation in the joints. A genetic history that is high in risk, when paired with genomic markers and environmental exposures, triggers a series of actions that not only results in synovitis and arthritis, but also affects a great number of organs that are not related to the joints. The identification of novel autoantibodies playing key roles in different stages of disease remains an issue of interest for RA. Therefore, autoantibodies are necessary to assist in making a diagnosis and prediction more quickly in RA. Anti-Carbamylated Protein antibodies are a different class of anti- transformed protein antibody that is often found in the blood of RA patients. Objective: Rheumatoid arthritis has a recently discovered biomarker, which is an antibody called anti-carbamylated protein (CarP). Our aim is to evaluate the usefulness of anti-CarP as a diagnostic tool for RA. Participants and methods: The study conducted on 60 people diagnosed with RA as well as 60 people who served as healthy controls. Both the disease activity score (DAS28) and the health assessment questionnaire (HAQ) were evaluated. Estimates were made based on laboratory examinations such as ESR and rheumatoid factor (RF). Anti-CarP and Anti-CCP antibodies were measured by enzyme-linked immune-sorbent assay. Results:Anti-CarP levels were considerably higher in the patients with RA compared to the group that provided as a control (p > 0.000). Therefore, the sensitivity and specificity for anti-CarP antibodies were 39% and 98% respectively, while the sensitivity and specificity for anti-CCP antibodies were 83% and 95% respectively, and for RF were 68% and 83% respectively. The area under the curve (AUC) for anti-CarP antibodies was 0.67. 
 Conclusions:
 Anti-CarP antibodies had comparatively lower sensitivity and slightly higher specificity than Anti-CCP.These findings suggest that anti-CarP antibodies works as an additional role in the diagnosis of RA.

Comprehensive Review on Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory, systemic, progressive, autoimmune disease in which the body’s immune system whose major role is to protect the health by attacking foreign bacteria and viruses are mistakenly, attacking the joints resulting in thickened synovium, pannus formation & destruction of bone, cartilage. Many complications can follow such as permanent joint damage requiring arthroplasty, rheumatoid vasculitis and elty’s syndrome requiring splenectomy if it remains unaddressed. Still now researchers are unable to know the exact cause of this disease. However, it is believed that age, gender, genetics and environmental exposure (cigarette smoking, air pollutants and occupational) play a role in development of RA. As there is no cure for RA, the treatment goals are to reduce the pain and stop/slow the further damage. The identification of novel autoantibodies has improved diagnostic accuracy, and newly developed classification criteria facilitate the recognition and study of the disease early in its course. New clinical assessment tools are able to better characterize disease activity states, which are correlated with progression of damage and disability and permit improved follow up. In addition, better understanding of the pathogenesis of RA through recognition of key cells and cytokines has led to the development of targeted disease-modifying antirheumatic drugs. Altogether, the improved understanding of the pathogenetic processes involved, rational use of established drugs and development of new drugs and reliable assessment tools have drastically altered the lives of individuals with RA over the past 2 decades. In this review, we discuss the epidemiology, pathophysiology, diagnosis and management of RA. Keywords: Rheumatoid arthritis, Pathogenesis, Disease modifying anti-arthritic drugs, Genetics, Environmental, Autoantibodies

Towards the identification of novel autoantibodies in Sjögren's syndrome.

Primary Sjögren's syndrome may be difficult to diagnose when antibodies against Ro/SSA are lacking, and can be grouped in at least four clusters indicating different pathophysiological pathways. Novel biomarkers, in particular autoantibodies, would be helpful in diagnosing Sjögren's syndrome and in further identification and characterisation of the clusters.In this review, we describe new technologies that may be utilised in the rapid identification of novel autoantibodies, and an example of how well characterised patients, here from the HarmonicSS cohort, are a prerequisite in the discovery of clinically meaningful biomarkers. This translational approach hold promise to optimise the diagnosis and treatment of individual pSS patient subsets.

Identification of novel autoantibodies in ascites of relapsed paclitaxel-resistant gastric cancer with peritoneal metastasis using immunome protein microarrays and proteomics.

Gastric cancer (GC) patients with peritoneal metastasis usually have extremely poor prognosis. Intraperitoneal infusion of paclitaxel (PTX) provides an effective treatment, but relapse and PTX-resistance are unavoidable disadvantages, and it is difficult to monitor the occurrence of PTX-resistance. The aim of this study was to explore novel autoantibodies in the ascites of individuals with relapsed PTX-resistant GC with peritoneal metastasis. Ascites samples were collected before PTX infusion and after the relapse in 3 GC patients. To determine the expression of significantly changed proteins, we performed autoantibody profiling with immunome protein microarrays and tandem mass tag (TMT) quantitative proteomics, and then, the overlapping proteins were selected. Thirty-eight autoantibodies that were differentially expressed between the ascites in the untreated group and relapsed PTX-resistant group were identified. For confirmation of the results, TMT quantitative proteomics was performed, and 842 dysregulated proteins were identified. Four proteins, TPM3, EFHD2, KRT19 and vimentin, overlapped between these two assays. Our results first revealed that TPM3, EFHD2, KRT19 and vimentin were novel autoantibodies in the ascites of relapsed PTX-resistant GC patients. These autoantibodies may be used as potential biomarkers to monitor the occurrence of PTX-resistance.

Identification of Novel Autoantibodies Based on the Human Proteomic Chips and Evaluation of Their Performance in the Detection of Gastric Cancer.

Autoantibodies against tumor-associated antigens (TAAbs) can be used as potential biomarkers in the detection of cancer. Our study aims to identify novel TAAbs for gastric cancer (GC) based on human proteomic chips and construct a diagnostic model to distinguish GC from healthy controls (HCs) based on serum TAAbs. The human proteomic chips were used to screen the candidate TAAbs. Enzyme-linked immunosorbent assay (ELISA) was used to verify and validate the titer of the candidate TAAbs in the verification cohort (80 GC cases and 80 HCs) and validation cohort (192 GC cases, 128 benign gastric disease cases, and 192 HCs), respectively. Then, the diagnostic model was established by Logistic regression analysis based on OD values of candidate autoantibodies with diagnostic value. Eleven candidate TAAbs were identified, including autoantibodies against INPP5A, F8, NRAS, MFGE8, PTP4A1, RRAS2, RGS4, RHOG, SRARP, RAC1, and TMEM243 by proteomic chips. The titer of autoantibodies against INPP5A, F8, NRAS, MFGE8, PTP4A1, and RRAS2 were significantly higher in GC cases while the titer of autoantibodies against RGS4, RHOG, SRARP, RAC1, and TMEM243 showed no difference in the verification group. Next, six potential TAAbs were validated in the validation cohort. The titer of autoantibodies against F8, NRAS, MFGE8, RRAS2, and PTP4A1 was significantly higher in GC cases. Finally, an optimal prediction model with four TAAbs (anti-NRAS, anti-MFGE8, anti-PTP4A1, and anti-RRAS2) showed an optimal diagnostic performance of GC with AUC of 0.87 in the training group and 0.83 in the testing group. The proteomic chip approach is a feasible method to identify TAAbs for the detection of cancer. Moreover, the panel consisting of anti-NRAS, anti-MFGE8, anti-PTP4A1, and anti-RRAS2 may be useful to distinguish GC cases from HCs.

Identification of novel autoantibodies based on the protein chip encoded by cancer-driving genes in detection of esophageal squamous cell carcinoma

ABSTRACT The purpose of this study was to identify novel autoantibodies against tumor-associated antigens (TAAbs) and explore the optimal diagnosis model based on the protein chip for detecting esophageal squamous cell carcinoma (ESCC). The human protein chip based on cancer-driving genes was customized to discover candidate TAAbs. Enzyme-linked immunosorbent assay was applied to verify and validate the expression levels of candidate TAAbs in the training cohort (130 ESCC and 130 normal controls) and the validation cohort (125 ESCC and 125 normal controls). Logistic regression analysis was adopted to construct the diagnostic model based on the expression levels of autoantibodies with diagnostic value. Twelve candidate autoantibodies were identified based on the protein chip according to the corresponding statistical methods. In both the training cohort and validation cohort, the expression levels of 10 TAAbs (GNA11, PTEN, P53, SRSF2, GNAS, ACVR1B, CASP8, DAXX, PDGFRA, and MEN1) in ESCC patients were higher than that in normal controls. The panel consisting of GNA11, ACVR1B and P53 demonstrated favorable diagnostic power. The sensitivity, specificity and accuracy of the model in the train cohort and the validation cohort were 71.5%, 93.8%, 79.6% and 77.6%, 81.6%, 70.8%, respectively. In either cohort, there was no correlation between positive rate of the autoantibody panel and clinicopathologic features for ESCC patients. Protein chip technology is an effective method to identify novel TAAbs, and the panel of 3 TAAbs (GNA11, ACVR1B, and P53) is promising for distinguishing ESCC patients from normal individuals.

Identification of Novel Autoantibodies Associated With Psoriatic Arthritis.

The autoimmune etiology in psoriasis remains to be clarified. We therefore undertook this study to identify novel pathogenic autoantigens and autoantibodies in patients with psoriasis, with the aim of shedding light on the molecular and cellular basis of the pathogenesis of psoriasis and psoriatic arthritis (PsA). In this study, we developed an autoantigen array system that harbors a variety of antigens, including typical autoantigens in rheumatic diseases as well as skin antigens, inflammatory mediators, and putative autoantigens in psoriasis. Serum samples from patients with psoriasis (n = 73) were used to interrogate the antigens on the array. In addition, enzyme-linked immunosorbent assays of individual autoantibodies were used in validation studies. Levels of several autoantibodies were found to be elevated in the serum of patients with psoriasis compared to healthy controls; in particular, IgG autoantibodies against 2 novel antigens, LL-37 and ADAMTS-L5, were significantly increased in patients with psoriasis. Importantly, serum levels of IgG autoantibodies against LL-37 and ADAMTS-L5 were correlated with the Psoriasis Area and Severity Index, and reflected disease progression in longitudinally collected serum samples from patients with psoriasis. Importantly, both anti-ADAMTS-L5 and anti-LL-37 autoantibody levels were also significantly elevated in psoriasis patients with PsA compared to those without PsA, suggesting that these molecules may be involved in the pathogenesis of PsA. Our findings indicate that these identified autoantibodies may be useful biomarkers and may serve as therapeutic targets in psoriasis and PsA.

Rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic, inflammatory, autoimmune disease that primarily affects the joints and is associated with autoantibodies that target various molecules including modified self-epitopes. The identification of novel autoantibodies has improved diagnostic accuracy, and newly developed classification criteria facilitate the recognition and study of the disease early in its course. New clinical assessment tools are able to better characterize disease activity states, which are correlated with progression of damage and disability, and permit improved follow-up. In addition, better understanding of the pathogenesis of RA through recognition of key cells and cytokines has led to the development of targeted disease-modifying antirheumatic drugs. Altogether, the improved understanding of the pathogenetic processes involved, rational use of established drugs and development of new drugs and reliable assessment tools have drastically altered the lives of individuals with RA over the past 2 decades. Current strategies strive for early referral, early diagnosis and early start of effective therapy aimed at remission or, at the least, low disease activity, with rapid adaptation of treatment if this target is not reached. This treat-to-target approach prevents progression of joint damage and optimizes physical functioning, work and social participation. In this Primer, we discuss the epidemiology, pathophysiology, diagnosis and management of RA.

Identification of Novel Autoantibodies in Type 1 Diabetic Patients Using a High-Density Protein Microarray

Autoantibodies can facilitate diagnostic and therapeutic means for type 1 diabetes (T1DM). We profiled autoantibodies from serum samples of 16 T1DM patients, 16 type 2 diabetic (T2DM) patients, and 27 healthy control subjects with normal glucose tolerance (NGT) by using protein microarrays containing 9,480 proteins. Two novel autoantibodies, anti-EEF1A1 and anti-UBE2L3, were selected from microarrays followed by immunofluorescence staining of pancreas. We then tested the validity of the candidates by ELISA in two independent test cohorts: 1) 95 adults with T1DM, 49 with T2DM, 11 with latent autoimmune diabetes in adults (LADA), 20 with Graves disease, and 66 with NGT and 2) 33 children with T1DM and 34 healthy children. Concentrations of these autoantibodies were significantly higher in T1DM patients than in NGT and T2DM subjects (P < 0.01), which was also confirmed in the test cohort of children (P < 0.05). Prevalence of anti-EEF1A1 and anti-UBE2L3 antibodies was 29.5% and 35.8% in T1DM, respectively. Of note, 40.9% of T1DM patients who lack anti-GAD antibodies (GADA) had anti-EEF1A1 and/or anti-UBE2L3 antibodies. These were also detected in patients with fulminant T1DM but not LADA. Our approach identified autoantibodies that can provide a new dimension of information indicative of T1DM independent of GADA and new insights into diagnosis and classification of T1DM.

Detection of anti-p155/140, anti-p140, and antiendothelial cells autoantibodies in patients with juvenile dermatomyositis.

The pathogenesis of juvenile dermatomyositis (JDM), the most common idiopathic inflammatory myopathy in children, is unclear. The identification of novel autoantibodies in JDM may have clinical implications. The aim of this study was to assess the presence of anti-p155/140, anti-p140 antibodies, and antiendothelial cells antibodies (AECA) in patients with JDM and to correlate autoantibodies with clinical manifestations. Serum AECA against human umbilical vein endothelial cells were detected by enzyme-linked immunosorbent assay in 25 patients with JDM and 17 normal controls. Immunoblotting was performed to detect serum anti-p155/140 and anti-p140 antibodies. Patients with JDM had significantly higher serum levels of AECA than healthy controls (p = 0.002). Nineteen patients (76%) and five control patients (29.4%) had positive AECAs (p = 0.003). The cutoff point of serum levels of AECA was determined by the receiver operating characteristic (ROC) curve analysis. Anti-p155/140 and anti-p140 antibodies were detected in 9 patients and 7 patients with JDM (36% and 28%, respectively). Anti-p155/140 antibodies were significantly associated with higher proportion of ESR elevation (100% vs. 0%, p = 0.006), higher erythrocyte sedimentation rate levels at diagnosis (40.3 ± 15.5 vs. 13.4 ± 5.3, p = 0.019), and a younger age at diagnosis (5.2 ± 3.2 years vs. 8.0 ± 3.0 years, p = 0.03). anti-p155/140, anti-p140, and AECA antibodies are significantly associated with JDM. The roles of autoantibodies in the pathogenesis await further investigation.

Identification of novel autoantibodies to GABAB receptors in patients with neuropsychiatric systemic lupus erythematosus

The gamma-aminobutyric acid type B receptors (GABAR(B)) are G-protein coupled receptors for GABA, the main inhibitory neurotransmitter in the brain. We identified GABAR(B) subunits as candidate antigens in patients with SLE using a random peptide display library. The aim of this study was to investigate the possible link between anti-GABAR(B) antibodies and disease activity and NPSLE. ELISA was performed with recombinant proteins of GABAR(B1b) and GABAR(B2) on serum samples from patients with SLE (n = 88), scleroderma (n = 20), myositis (n = 20) or vasculitis (n = 20) as well as healthy subjects (n = 20). Cerebrospinal fluid (CSF) from 23 patients with SLE was also examined. Autoantibodies to GABAR(Bs) were exclusive to patients with SLE (P < 0.001) and positively associated with SLEDAI (anti-GABAR(B1b), P = 0.001; anti-GABAR(B2), P < 0.001). Of note, autoantibodies were positively linked with NPSLE (anti-GABAR(B1b), P = 0.02; anti-GABAR(B2), P = 0.03). Moreover, anti-GABAR(Bs) was detected in 61.5% of CSF samples from patients with active NPSLE, a frequency that was significantly higher than that for patients with non-SLE syndromes. Anti-GABAR(B) antibodies could represent novel candidate markers for disease activity and NPSLE.

Identification of Novel Autoantibodies for Detection of Malignant Mesothelioma

BackgroundThe malignant mesothelioma (MM) survival rate has been hampered by the lack of efficient and accurate early detection methods. The immune system may detect the early changes of tumor progression by responding with tumor-associated autoantibody production. Hence, in this study, we translated the humoral immune response to cancer proteins into a potential blood test for MM.Methodology/Principal FindingsA T7 phage MM cDNA library was constructed using MM tumor tissues and biopanned for tumor-associated antigens (TAAs) using pooled MM patient and normal serum samples. About 1008 individual phage TAA clones from the biopanned library were subjected to protein microarray construction and tested with 53 MM and 52 control serum samples as a training group. Nine candidate autoantibody markers were selected from the training group using Tclass system and logistic regression statistical analysis, which achieved 94.3% sensitivity and 90.4% specificity with an AUC value of 0.89 in receiver operating characteristic analysis. The classifier was further evaluated with 50 patient and 50 normal serum samples as an independent blind validation, and the sensitivity of 86.0% and the specificity of 86.0% were obtained with an AUC of 0.82. Sequencing and BLASTN analysis of the classifier revealed that five of these nine candidate markers were found to have strong homology to cancer related proteins (PDIA6, MEG3, SDCCAG3, IGHG3, IGHG1).Conclusions/SignificanceOur results indicated that using a panel of 9 autoantibody markers presented a promising accuracy for MM detection. Although the results need further validation in high-risk groups, they provided the potentials in developing a serum-based assay for MM diagnosis.

Identification of novel autoantibodies in systemic autoimmunity using 10,000-antigen proteome arrays (P4006)

Abstract Systemic erythematosus lupus (SLE) is an autoimmune disease characterized by presence of autoantibodies against a broad spectrum of self-antigens. In order to identify novel serum autoantibodies associated with SLE, we utilized a protoarray bearing 10,000 antigens to screen IgG and IgM autoAbs in sera of SLE patients. 446 IgG and 1218 IgM autoAbs were significantly increased in SLE compared with health controls (p&amp;lt;0.05), in which 367 autAbs overlapped in IgG and IgM. Except the autoAbs previously identified in SLE patients, such as anti-DNA, Ro, La, etc., the protoarray also uncovered a group of novel autoAbs against a broad range of antigens. The increased expression of 16 novel autoantibodies in SLE, including IgG autoantibodies against APEX1, AURKA, BAG3, CSNK1G1, EIF2C1, HMGB1, IFIT5, MAPKAPK3, PADI4, PKRKA, RALGPS1, RGS3, SRP19, STIP1, UBE2S and VRK1 were further confirmed by ELISA. Gene expression analysis revealed that some of the self-antigens also significantly upregulated on transcription level. In addition to uncovering ~500 novel autoantibody specificities, the novel arrays also shed light on some of the pathogenic pathways leading to disease in systemic lupus. In conclusion, protoarray provide a powerful tool for identification of novel autoantibodies in system autoimmune diseases.

Autoantibodies to a 140‐kd protein in juvenile dermatomyositis are associated with calcinosis

ObjectiveThe identification of novel autoantibodies in juvenile dermatomyositis (DM) may have etiologic and clinical implications. The aim of this study was to describe autoantibodies to a 140-kd protein in children recruited to the Juvenile DM National Registry and Repository for UK and Ireland.MethodsClinical data and sera were collected from children with juvenile myositis. Sera that recognized a 140-kd protein by immunoprecipitation were identified. The identity of the p140 autoantigen was investigated by immunoprecipitation/immunodepletion, using commercial monoclonal antibodies to NXP-2, reference anti-p140, and anti-p155/140, the other autoantibody recently described in juvenile DM. DNA samples from 100 Caucasian children with myositis were genotyped for HLA class II haplotype associations and compared with those from 864 randomly selected UK Caucasian control subjects.ResultsSera from 37 (23%) of 162 patients with juvenile myositis were positive for anti-p140 autoantibodies, which were detected exclusively in patients with juvenile DM and not in patients with juvenile DM–overlap syndrome or control subjects. No anti-p140 antibody–positive patients were positive for other recognized autoantibodies. Immunodepletion suggested that the identity of p140 was consistent with NXP-2 (the previously identified MJ autoantigen). In children with anti-p140 antibodies, the association with calcinosis was significant compared with the rest of the cohort (corrected P < 0.005, odds ratio 7.0, 95% confidence interval 3.0–16.1). The clinical features of patients with anti-p140 autoantibodies were different from those of children with anti-p155/140 autoantibodies. The presence of HLA–DRB1*08 was a possible risk factor for anti-p140 autoantibody positivity.ConclusionThis study has established that anti-p140 autoantibodies represent a major autoantibody subset in juvenile DM. This specificity may identify a further immunogenetic and clinical phenotype within the juvenile myositis spectrum that includes an association with calcinosis.