Circulating immune complexome analysis identified anti-tubulin-α-1c as an inflammation associated autoantibody with promising diagnostic value for Behcet's Disease

Behçet's syndrome: recent advances to aid diagnosis

Behçet's syndrome is a recurring inflammatory multiorgan disorder affecting the skin, mucosa, eyes, joints, stomach, and central nervous system. Behçet's syndrome epidemiology varies greatly among populations (0.64-420/100,000), and Behçet's syndrome has gained increasing international acclaim in the recent 50 years due to raising awareness of the syndrome, although it is rare in most population. In addition to the unclear etiology of the syndrome, the diagnosis of Behçet's syndrome is complicated by a vague clinical presentation, phenotypic heterogeneity and/or incomplete representation, and the lack of any specific laboratory, radiographic, or histological findings. There exists a dire need to elucidate factors that contribute to disease pathogenesis and/or are associated with clinical features of Behçet's syndrome and the classification of different forms of the syndrome. The identification of such molecular, cellular, and/or clinical factors are crucial for timely diagnosis and efficacious management of Behçet's syndrome. We discuss recent advances in the clinical diagnosis of Behçet's syndrome and related contributions of genetics, epigenetics, microbiome, inflammasomes, and autoantibodies to the improved diagnosis, management, and understanding of Behçet's syndrome.

Anti-tubulin-alpha-1c antibody as a marker of value in Behçet syndrome

Background

Behçet’s syndrome (BS) is a multi-systemic vasculitis characterized by recurrent oral ulcers, genital ulcers, ocular lesions, and other systemic manifestations. As there is no laboratory diagnostics of BS, the diagnosis is mainly clinical.

Objective

To investigate the utility of the autoantibody against tubulin-α-1c in diagnosis of BS and its clinical significance.

Methods

Sixty BS patients and sixty healthy controls were enrolled in this study. We assessed all patients by Behçet disease current activity form (BDCAF), routine laboratory investigations, and immunological markers (ANA, anti-DNA, ANCA). Anti-endothelial cell antibodies (AECA) and anti-tubulin-alpha-1c antibodies were performed for all participants.

Results

Regarding duration of illness, Birmingham Vasculitis Activity Score (BVAS), and BDCAF, the mean value was 4.77 ± 4.239, 19.80 ± 10.020, and 9.52 ± 5.476, respectively. On comparing laboratory investigations, there was only significant increase in anti-tubulin-alpha-1c antibody in BS patients compared to healthy controls. Regarding AECA, there was no any significant correlation except with CRP. Anti-tubulin-alpha-1c detected significant direct correlation with the presence of posterior uveitis, panuveitis, and venous thrombosis as well as BVAS, C4, and protein/creatinine ratio. Regarding diagnostic performance of both AECA and anti-tubulin-alpha-1c, the cutoff value of AECA for diagnosis was 27.250, with sensitivity and specificity of 93.3% and 96.7%, respectively. The cutoff value of the anti-tubulin-alpha-1c for diagnosis was 22.300, with sensitivity and specificity of 100% and 96.7% respectively.

Conclusion

Anti-tubulin-α-1c antibodies are of diagnostic value in BS and are indicative of activity with 100% sensitivity and 96.7% specificity.

Key Points • There is lack of specific laboratory, radiological, or histological diagnostics for Behcet syndrome. • We aimed to evaluate the significance of tubulin-α-1c autoantibody in diagnosis of Behcet syndrome. • There is elevation of tubulin-α-1c autoantibody with sensitivity and specificity of 100% and 96.7%, respectively.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10067-021-06025-7.

Detection of Novel Urine Markers Using Immune Complexome Analysis in Bladder Cancer Patients: A Preliminary Study

BACKGROUND/AIM

Little is known on urine biomarkers that are associated with malignant behavior in patients with bladder cancer (BC). Our aim was to identify BC-related factors in urine samples using our original method "immune complexome analysis", based on detecting the immune complex (IC).

PATIENTS AND METHODS

Immune complexome analysis was performed using urine samples from 97 BC patients, including 67 with non-muscle invasive BC (NMIBC).

RESULTS

Eight IC-antigens were recognized as candidates for BC-related factors from 20,165 proteins. IC-serum albumin, -fibrinogen γ chain, -hemoglobin subunit α, -hemoglobin subunit β, -ceruloplasmin, and fibrinogen β chain were significantly associated with either pathological features and/or outcome. IC-ceruloplasmin was most widely associated with pathological features in all BC patients and lamina propria invasion and urinary tract recurrence in NMIBC.

CONCLUSION

Based on detection of IC-antigens it was demonstrated that six IC-antigens, especially IC-ceruloplasmin, are potential urine biomarkers in BC.

[Significance of anti-tubulin-α-1C autoantibody in systemic sclerosis]

OBJECTIVE

To detect the serum level of a novel autoantibody, anti-tubulin-α-1C, in patients with systemic sclerosis (SSc) and to investigate its clinical significance.

METHODS

Anti-tubulin-α-1C antibody levels were determined by enzyme-linked immunosorbent assay (ELISA) in 62 patients with SSc, 38 systemic lupus erythematosus (SLE), 24 primary Sjögren's syndrome (pSS) patients, and 30 healthy controls (HCs). Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), immunoglobulin A(IgA), immunoglobulin M (IgM), immunoglobulin G (IgG), C3, C4, rheumatoid factor (RF), antinuclear antibody(ANA), anti-centromere antibodies(ACA), anticardiolipin (aCL), anti-dsDNA antibody, anti-Sm antibody, anti-RNP antibody, anti-Scl-70 antibody, anti-Ro52 antibody, anti-SSA antibody, anti-SSB antibody, centromere protein A(CENP-A), centromere protein B (CENP-B) were measured by standard laboratory techniques. Raynaud's phenomenon and modified Rodnan skin score(MRSS) were recorded to evaluate the disease status of SSc. Independent sample t test, Chi square test, Mann-Whitney U test, Spearman rank correlation were used for statistical analyses.

RESULTS

The serum anti-tubulin-α-1C antibody concentration in SSc group was 81.24±34.38, the serum anti-tubulin-α-1C antibody concentration in SLE group was 87.84±38.52, the serum anti-tubulin-α-1C antibody concentration in pSS group was 59.79±25.24, and the serum anti-tubulin-α-1C antibody concentration in healthy group was 39.37±18.7. Multivariate analysis revealed that anti-tubulin-α-1C antibody levels were significantly increased in the SSc and SLE patients. The expression level of anti-tubulin-α-1C antibody in SSc was higher compared with the pSS group and the health control group (P < 0.01). Further analysis demonstrated that the elevated anti-tubulin-α-1C antibody were correlated with the SSc inflammation and disease activity markers ESR(r=0.313, P=0.019), The levels of anti-tubulin-α-1C antibody were also significantly correlated with MRSS(r=0.636, P < 0.01). The best cut-off value for the diagnose of SSc was 76.77 as mean+2SD value. The proportion of Raynaud's phenomenon was higher in the group of anti-tubulin-α-1C autoantibody-postive SSc patients than that in anti-tubulin-α-1C autoantibody negative group(71.4% vs. 37.5%, P=0.039). The proportions of anti-Scl-70 antibody, anti-CENP antibody and anti-cardiolipin antibody were higher in the group of anti-tubulin-α-1C autoantibody-postive SSc patients than in the anti-tubulin-α-1C autoantibody negative group (37.9% vs. 15.2%, 34.5% vs. 12.1%, 13.8 vs. 0, respectively, all P < 0.05).

CONCLUSION

Based on this explorative stu-dy, the level of anti-tubulin-α-1C antibody increased in the serum of the patients with SSc. There were correlations between anti-tubulin-α-1C autoantibody and clinical and laboratory indicators of the SSc patients. It may become a novel biomarker indicative of active SSc and could be applied in future clinical practice.

Prevalence of antiphospholipid antibodies in Behçet's disease: A systematic review and meta-analysis

Behçet's disease (BD) is a multifactorial systemic inflammatory disease of unknown aetiology characterised by several clinical manifestations including vascular involvements (i.e., both arterial and venous thrombosis). Antiphospholipid antibodies (aPLs)-including anticardiolipin (aCL), anti-β2-glycoprotein I (β2-GPI) antibodies and lupus anticoagulant (LA) are detected in systemic autoimmune diseases which contribute to thrombosis. The aim of this systematic review and meta-analysis was to evaluate the prevalence of aPLs in patients with BD as compared to controls. A protocol was registered in PROSPERO (Registration No. CRD42018088125) and a systematic literature search was conducted through PubMed, Web of Science, Embase, Scopus and ScienceDirect databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using random-effects model. Quality assessment was carried out by using the modified 9-star Newcastle-Ottawa Scale (NOS). Publication bias was evaluated via visualisation of contour- enhanced and trim and fill funnel plots along with Begg's and Egger's tests. We included ten case-control studies (a total of 999 participants from 380 BD patients and 619 controls) based on the inclusion criteria. The prevalence of aCL (OR: 12.10, 95% CI: 5.15-28.41, p<0.00001) and anti-β2-GPI antibodies (OR: 23.57, 95% CI: 1.31-423.63, p = 0.03) were statistically significant, however, the prevalence of LA was not significant (OR: 13.77, 95% CI: 0.65-293.59, p = 0.09). The results remained statistically significant from different sensitivity analyses which represented the robustness of this meta-analysis. According to the NOS, 50.0% of the studies were considered as of high methodological quality (low risk of bias). No significant publication bias was detected from contour-enhanced and trim and fill funnel plots or Begg's and Egger's tests. This meta-analysis established that there is a significantly high prevalence of aPLs (i.e., aCL and anti-β2-GPI antibodies) in patients with BD when compared to controls.

Autoimmune diseases in China

Autoimmune diseases, such as rheumatoid arthritis, systematic lupus erythematosus and Sjögren's syndrome, are a group of diseases characterized by the activation of immune cells and excessive production of autoantibodies. Although the pathogenesis of these diseases is still not completely understood, studies have shown that multiple factors including genetics, environment and immune responses play important roles in the development and progression of the diseases. In China, there are great achievements in the mechanisms of autoimmune diseases during the last decades. These studies provide new insight to understand the diseases and also shed light on the development of novel therapy.

Biomarkers in Vasculitides of the Nervous System

Besides being affected by the rare and severe primary angiitis of the central nervous system (PACNS) the nervous system is also affected by primary systemic vasculitides (PSV). In contrast to PACNS, PSV affect not only the central but also the peripheral nervous system, resulting in a large array of potential symptoms. Given the high burden of disease, difficulties in distinguishing between differential diagnoses, and incomplete pathophysiological insights, there is an urgent need for additional precise diagnostic tools to enable an earlier diagnosis and initiation of effective treatments. Methods available to date, such as inflammatory markers, antibodies, cerebrospinal fluid (CSF) analysis, imaging, and biopsy, turn out to be insufficient to meet all current challenges. We highlight the use of biomarkers as an approach to extend current knowledge and, ultimately, improve patient management. Biomarkers are considered to be useful for disease diagnosis and monitoring, for predicting response to treatment, and for prognosis in clinical practice, as well as for establishing outcome parameters in clinical trials. In this article, we review the recent literature on biomarkers which have been applied in the context of different types of nervous system vasculitides including PACNS, giant-cell arteritis, Takayasu's arteritis, polyarteritis nodosa, ANCA (anti-neutrophil cytoplasm antibody)-associated vasculitides, cryoglobulinemic vasculitis, IgA vasculitis, and Behçet's disease. Overall, the majority of biomarkers is not specific for vasculitides of the nervous system.

[Clinical Pharmaceutical Research Based on New Proteome Analysis Based on Chromatographic Separation]

Comprehensive identification of antigens in immune complexes (IC-antigens) is beneficial to provide insights into pathophysiology and could form the basis for novel diagnostic and treatment strategies for many immune-related diseases. Immune complexome analysis is a method for comprehensively identifying and profiling IC-antigens in biological fluids (such as serum and cerebrospinal fluid). We applied this strategy to the analysis of circulating ICs in autoimmune diseases (rheumatoid arthritis, Sjögren's syndrome, systemic scleroderma, and systemic lupus erythematosus), infectious diseases, and cancers. Fluorogenic derivatization-liquid chromatography-tandem mass spectrometry (FD-LC-MS/MS) consists of fluorogenic derivatization of proteins, followed by HPLC of the derivatized proteins, isolation of the proteins differentially expressed in a certain group, enzymatic digestion of the isolated proteins followed by LC-tandem MS using a database-searching algorithm for protein identification. We have applied this method to understand the cardioprotective effect of pre-administration of docetaxel in adriamycin/docetaxel combination anti-cancer therapy, and the cellular processes that are affected by non-steroidal anti-inflammatory drugs (NSAIDs) in mouse stomach tissue during ulcer formation.