Novel Biomarker Of Disease Activity Research Articles

Diversity and Epitope Spreading of Anti-RNA Polymerase III Antibodies in Systemic Sclerosis: A Potential Biomarker for Skin and Lung Involvement.

Epitope spreading (ES), involving autoantibodies, plays a crucial role in the development and persistence of autoimmune reactions in various autoimmune diseases. This study aimed to investigate the relationship between ES of anti-RNA polymerase III (RNAP III) antibodies (ARAs) and the clinical manifestations of systemic sclerosis (SSc). We investigated whether intermolecular ES occurs in the subunits of the RNAP III complex and whether intramolecular ES targets the major antigen, RNA polymerase III subunit A(RPC1), in patients with SSc. To achieve this, we synthesized 17 full-length subunit proteins of the RNAP III complex and 5 truncated forms of RPC1 in vitro using a wheat germ cell-free translation system. Subsequently, we prepared antigen-binding plates and measured autoantibodies in the serum of patients with SSc. Autoantibodies against different RNAP III complex subunits were found in patients who were ARA-positive with SSc. The intermolecular ES indicators significantly correlated with the modified Rodnan skin thickness score (mRSS) and surfactant protein-D, a biomarker of interstitial lung disease. However, the extent of disease on high-resolution computed tomography or pulmonary function tests did not show any significant correlation. Intramolecular ES indicator against RPC1 were significantly correlated with mRSS and renal crisis. Furthermore, longitudinal assessment of ES in RNAP III complex subunits correlated with mRSS and exhibited potential as a disease activity biomarker. Our findings indicate a correlation between ES levels and the severity of skin sclerosis or the risk of other complications in SSc. This study suggests that measuring ES in SSc serves as a novel biomarker for disease activity.

Fibroblast activation protein and disease severity, progression, and survival in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive fibrosis in the lungs. Activated fibroblasts play a central role in fibrogenesis and express fibroblast activation protein α. A truncated, soluble form (sFAP) can be measured in blood and is a potential novel biomarker of disease activity. The aim was to study the association between sFAP and clinical, radiological, and histopathological measures of disease severity, progression, and survival in a prospective, multicentre, real-world cohort of patients with IPF. Patients with IPF were recruited from the tertiary interstitial lung disease centres in Denmark and followed for up to 3 years. Baseline serum levels of sFAP were measured by ELISA in patients with IPF and compared to healthy controls. Pulmonary function tests, 6-minute walk test and quality of life measures were performed at baseline and during follow-up. The study included 149 patients with IPF. Median sFAP in IPF was 49.6 ng/mL (IQR: 43.1-61.6 ng/mL) and in healthy controls 73.8 ng/mL (IQR: 62.1-92.0 ng/mL). Continuous sFAP was not associated with disease severity, progression or survival (p > 0.05). After dichotomization of sFAP below or above mean sFAP + 2 SD for healthy controls, higher levels of sFAP were associated with lower FVC % predicted during follow-up (p < 0.01). Higher than normal serum levels of sFAP were associated with longitudinal changes in FVC % predicted, but sFAP did not show clear associations with other baseline or longitudinal parameters. As such, sFAP has limited use as a biomarker of disease progression or survival in patients with IPF.

Review of the Longitudinal Management of Autoimmune Encephalitis, Potential Biomarkers, and Novel Therapeutics.

Increasing awareness and earlier diagnosis of autoimmune encephalitis (AE) have led to a greater number of patients being cared for longitudinally by neurologists. Although many neurologists are now familiar with the general approach to diagnosis and acute immunosuppression, this review aims to provide neurologists with guidance related to management beyond the acute phase of disease, including long-term immunosuppression, monitoring, potential biomarkers of disease activity, outcome measures, and symptom management. Observational studies in AE have demonstrated that early diagnosis and treatment is associated with improved neurologic outcomes, particularly in AE with antibodies targeting neuronal cell surface/synaptic proteins. The literature regarding long-term management is evolving. In addition to traditional immunosuppressive approaches, there is emerging use of novel immunosuppressive therapies (ISTs) in case series, and several randomized controlled trials are planned. Novel biomarkers of disease activity and methods to measure outcomes and response to treatment are being explored. Furthermore, it is increasingly recognized that many individuals have chronic symptoms affecting quality of life including seizures, cognitive impairment, fatigue, sleep disorders, and mood disorders, and there are emerging data supporting the use of patient centered outcome measures and multidisciplinary symptom-based care. This review aims to summarize recent literature and offer a practical approach to long-term management of adult patients with AE through a multidisciplinary approach. We summarize current knowledge on ISTs, potential biomarkers of disease activity, outcome measures, and long-term sequelae. Further research is needed to answer questions regarding optimal IST, biomarker validity, and sequelae of disease.

A novel long noncoding RNA ENST00000597482 serves as a potential biomarker for disease activity and diagnosis of systemic lupus erythematosus.

Emerging evidence indicate that long noncoding RNAs (lncRNAs) may play an important role in the pathogenesis of systemic lupus erythematosus (SLE) however, the contribution of lncRNAs to SLE remains largely unclear. Our study aimed to explore the lncRNA expression profiles in peripheral blood mononuclear cells (PBMCs) from SLE patients. LncRNA sequencing was used to detect differentially expressed genes in PBMCs from 5 SLE-MIX samples and 3 healthy controls (HC)-MIX samples, and the expression of selected lncRNAs was further verified by real-time quantitative polymerase chain reaction (RT‒qPCR). The correlation of lncRNA expression with laboratory indicators as well the SLE disease activity index 2000 (SLEDAI‒2K) score from 72 SLE patients was assessed by Spearman's test. The association between lncRNA ENST00000597482 and organ involvement in SLE patients was determined by the Mann‒Whitney U test. Moreover, lymphocyte subsets in peripheral blood from SLE patients were measured by flow cytometry. In addition, the diagnostic value of lncRNAs in predicting SLE was evaluated by receiver operating characteristic (ROC) curve analysis. The lncRNA expression profiles demonstrated 218 differentially expressed lncRNAs, including 121 upregulated genes and 97 downregulated genes, in PBMCs from SLE patients compared to HCs. Among the 10 candidate genes selected, only lncRNA ENST00000597482, which was lower in SLE PBMCs than in HCs, was consistent with the sequencing results. LncRNA ENST00000597482 expression was negatively correlated with SLEDAI-2K score and the titres of ANA antibodies and anti-double-stranded DNA (anti-dsDNA) antibodies. Of note, SLE patients with lower expression of lncRNA ENST00000597482 were prone to develop organ involvement. Furthermore, lncRNA ENST00000597482 exhibited potential diagnostic value in differentiating SLE patients from HCs. LncRNA ENST00000597482 expression was lower in PBMCs from SLE patients than HCs and was negatively correlated with the SLEDAI-2K score and autoantibody titres. In addition, lncRNA ENST00000597482 could act as a novel biomarker for disease activity and diagnosis of SLE.

The circular RNA hsa_circ_0045800 serves as a favorable biomarker in pathogenesis of sjögren's syndrome

BackgroundCircular RNAs (circRNAs) play various roles in the development of many autoimmune diseases. However, their expression profiles and specific function in Sjögren's Syndrome remains largely unknown.ObjectivesWe aimed to investigate circRNAs potential diagnostic value in primary Sjögren's syndrome (pSS) and contribution to the pathogenesis of pSS.MethodsThis study included 102 subjects, 51 pSS patients and 51 healthy controls. The concentration of hsa_circ_0045800 was analyzed in peripheral blood mononuclear cells obtained from 51 pSS patients and 51 healthy controls by qRT-PCR. We established a receiver operating characteristic curve (ROC) to assess the biological diagnostic value of hsa_circ_0045800 for pSS. In addition, we analyzed the correlation between hsa_circ_0045800 and disease activity in Sjogren's syndrome. A differential analysis was also conducted on the concentration of hsa_circ_0045800 in patients in pSS patients before and after treatment. We studied the downstream mechanism of hsa_circ_0045800 through bioinformatics analysis and confirmed it using luciferase reporter gene assay.ResultsWe confirmed that the concentration of hsa_circ_0045800 was elevated 10.4-fold in peripheral blood mononuclear cells of pSS patients than in healthy controls (p = 0.00). In the pSS active disease group, the concentration of hsa_circ_0045800 is 2.5-fold higher compared to the pSS non-active disease group (p = 0.04). The concentration of hsa_circ_0045800 after treatment was decreased by 80% compared with that before treatment (p = 0.037), suggesting its utility as a potential marker for monitoring treatment efficacy. ROC curve analysis showed that the diagnostic value of hsa_circ_0045800 in pSS patients was significantly higher than that in healthy controls, with an area under the curve of 0.865, a sensitivity of 74%, and a specificity of 92%. The concentration of hsa_circ_0045800 is correlated with various clinical factors: the concentration of hsa_circ_0045800 is positively associated with age (r = 0.328, P = 0.019), oral dryness (r = 0.331, P = 0.017), while it is negatively correlated with HGB (r = -0.435, P = 0.001) and and hypothyroidism (r = -0.318, P = 0.023). Bioinformatics predictions and luciferase assays indicated that hsa_circ_0045800 acts as a molecular sponge for miR-1247-5p, with SMAD2 being a target gene of miR-1247-5p.ConclusionOur study results show that hsa_circ_0045800 potentially contributes to the development and progression of pSS via the miR-1247-5p/SMAD2 pathway. Peripheral blood mononuclear cells are directly involved in the pathogenesis of pSS, and the discovery of hsa_circ_0045800 in peripheral blood mononuclear cells highlights its potential as a novel biomarker for disease activity and diagnosis in patients with pSS.Key Points• The concentration of hsa_circ_0045800 was higher in peripheral blood mononuclear cells of pSS patients.• Hsa_circ_0045800 promoted pSS progression through miR-1247-5p–SMAD2 axis.• Hsa_circ_0045800 is a potential biomarker for pSS.

18F-Sodium fluoride PET-CT visualizes disease activity in chronic nonbacterial osteitis in adults.

Chronic nonbacterial osteitis (CNO) is a rare disease spectrum, which lacks biomarkers for disease activity. Sodium fluoride-18 positron emission tomography/computed tomography ([18F]NaF-PET/CT) is a sensitive imaging tool for bone diseases and yields quantitative data on bone turnover. We evaluated the capacities of [18F]NaF-PET/CT to provide structural and functional assessment in adult CNO. A coss-sectional study was performed including 43 adult patients with CNO and 16 controls (patients referred for suspected, but not diagnosed with CNO) who underwent [18F]NaF-PET/CT at our expert clinic. Structural features were compared between patients and controls, and maximal standardized uptake values (SUVmax [g/mL]) were calculated for bone lesions, soft tissue/joint lesions, and reference bone. SUVmax was correlated with clinical disease activity in patients. Structural assessment revealed manubrial and costal sclerosis/hyperostosis and calcification of the costoclavicular ligament as typical features associated with CNO. SUVmax of CNO lesions was higher compared with in-patient reference bone (mean paired difference: 11.4; 95% CI: 9.4-13.5; p < .001) and controls (mean difference: 12.4; 95%CI: 9.1-15.8; p < .001). The highest SUVmax values were found in soft tissue and joint areas such as the costoclavicular ligament and manubriosternal joint, and these correlated with erythrocyte sedimentation rate in patients (correlation coefficient: 0.546; p < .002). Our data suggest that [18F]NaF-PET/CT is a promising imaging tool for adult CNO, allowing for detailed structural evaluation of its typical bone, soft-tissue, and joint features. At the same time, [18F]NaF-PET/CT yields quantitative bone remodeling data that represent the pathologically increased bone turnover and the process of new bone formation. Further studies should investigate the application of quantified [18F]NaF uptake as a novel biomarker for disease activity in CNO, and its utility to steer clinical decision making.

The emerging role of Growth Differentiation Factor 15 as a potential disease biomarker in juvenile dermatomyositis.

We aimed to investigate the potential of Growth Differentiation Factor 15 (GDF-15) as a novel biomarker for disease activity in Juvenile Dermatomyositis (JDM). We recruited children with juvenile myositis including juvenile dermatomyositis (n = 77), polymyositis (n = 6), and healthy controls (n = 22). GDF-15 levels in plasma were measured using ELISA. Statistical analyses were performed using non-parametric tests. Levels of GDF-15 were significantly elevated in JDM compared with healthy controls (p< 0.001). GDF-15 levels exhibited strong positive correlations with disease activity scores, including the Disease Activity Score (DAS) total score, DAS skin score, DAS muscle score, and Childhood Myositis Assessment Scale (CMAS). Additionally, GDF-15 levels could differentiate between active disease and remission based on the Physician Global Assessment of muscle score. Positive correlations were observed between levels of GDF-15 and creatine kinase, neopterin, and nailfold end row loops, indicating the potential involvement of GDF-15 in muscle damage, immune activation, and vascular pathology. ROC curve analysis showed GDF-15 to be more effective in assessing disease activity in JDM than creatine kinase (AUC 0.77, p= 0.001 and AUC 0.6369, p= 0.0738, respectively). GDF-15 may serve as a valuable biomarker for assessing disease activity in JDM. It exhibits better sensitivity and specificity than creatine kinase, and the levels correlate with various disease activity scores and functional measures. GDF-15 may provide valuable information for treatment decision-making and monitoring disease progression in JDM.

Urine L-selectin reflects clinical and histological renal disease activity and treatment response in lupus nephritis across multi-ethnicity.

There is an urgent need for novel biomarkers in lupus nephritis (LN). We report a non-invasive urinary biomarker, L-selectin, in two independent multi-ethnic cohorts. uL-selectin was tested cross-sectionally in a Chinese cohort (n=255) and a US cohort (n=219) of SLE patients and controls using ELISA. A longitudinal cohort includes 20 active Chinese LN patients. uL-selectin was significantly increased in active LN patients compared to active non-renal SLE, inactive LN, inactive non-renal SLE, chronic kidney disease patients, and healthy controls. uL-selectin positively correlated with global and renal disease activities as well as histological activity index and chronicity index (CI). Low uL-selectin was an independent predictor for high CI. During follow-up, uL-selectin levels decreased significantly in the complete renal remission group. uL-selectin is a novel biomarker of disease activity and renal histopathology in LN across multiple ethnicities. It also reflects treatment response in LN patients during follow up.

Clinical Significance of Immature Neutrophils in Relation to Disease Activity in Psoriatic Arthritis Patients

Abstract Background Psoriatic arthritis (PsA) is a complex type of progressive inflammatory arthritis associated with psoriasis. Prevalence of PsA has been reported 5.8–40.9% among patients suffering from psoriasis. A recent meta-analysis indicated that there is no gender predilection in patients with PsA. It shares genetic and clinical features with other forms of spondyloarthritis and affects different structures of the musculoskeletal system in addition to the skin and the nail. Neutrophils are crucial responders of the innate immune response, but the role played by neutrophils in psoriasis has not been well characterized. This thesis discussed the current understanding of the role and potential mechanisms of immature neutrophils in psoriatic arthritis. Objective To study the relation between immature neutrophils in blood and disease activity in psoriatic arthritis patients. Methods This randomized control trial, done on 50 PsA patients from Physical medicine, Rheumatology and Rehabilitation and Dermatology outpatient clinics of Ain Shams University hospital, included by CASPAR criteria, subjected to full medical history taking and thorough clinical examination with calculation of SPARCC, ASDAS and PASI scores.laboratory evaluation include CBC with differential white blood cell count for Immature Neutrophils percentage, ESR, CRP and Rheumatoid factor.CBC was compared with 20 age and sex matched healthy controls. Results The Immature Neutrophils mean ± SD(%) was found to be 5.99±1.57 in patients and was statistically significantly higher in them than in controls 2.25±1.16(P &amp;lt; 0.037) and it was statistically significantly correlated with disease activity according to ASDAS score, SPARCC, PASI score, ESR, CRP, RBCS, WBCS, Platelets, Enthesitis, Dactylitis, skin and nail affection. Conclusion This study highlighted the role of immature neutrophils as a novel biomarker for disease activity in psoriatic arthritis.

P122 Changes in Serum Levels of Cytokines with Methotrexate Monotherapy in Active Rheumatoid Arthritis: Results from a Multicentre, Randomized Controlled Trial on Methotrexate Escalation In Rheumatoid Arthritis

Abstract Background/Aims Identification of novel biomarkers of disease activity and prediction of treatment response in rheumatoid arthritis (RA) is an area of active research. Reliable biomarkers of methotrexate (MTX) response in RA are yet to be identified. We sought to study the change in serum levels of IL-6, MMP-3, and TNF-α with MTX monotherapy in patients with active RA. Methods Patients with active RA (SJC≥2 and TJC≥4) not on DMARDs (except HCQ and low-dose prednisolone) who had been enrolled in the multicentre, parallel-group RCT comparing two different MTX escalation strategies in RA (MEIRA) were included. All these patients received MTX monotherapy started at 15 mg/week and escalated to 25 mg/week by 4-8 weeks. Serum levels of IL-6, MMP-3, and TNF-α were measured by ELISA before starting MTX and after 16 weeks of MTX therapy. Responders were defined as patients who achieved a EULAR good or moderate response (based on DAS28ESR-3v) at 16 weeks. Analyses were intention-to-treat. Results 16 weeks of MTX therapy led to a decline in serum levels of both MMP-3 (p = 0.03, n = 129) and IL-6 (p = 0.048, n = 151). The decline in IL-6 levels was seen only in MTX responders (p = 0.003), but not in non-responders, while the decline in MMP-3 levels was seen in both MTX non-responders (p = 0.015) and responders (p = 0.44) (Table 1). Baseline (pre-treatment) serum levels of both IL-6 and MMP-3 were similar between MTX responders and non-responders. Correlations of serum levels of IL-6 (but not MMP-3) with measures of disease activity (DAS28, tender joint count) were weak but significant at 16 weeks. Serum TNF-α levels (n = 137) were undetectable in a majority of patients (93%). Serum IL-6 was not detectable in 67 (44%) patients at baseline. Conclusion Although serum levels of both MMP-3 and IL-6 reduced significantly with MTX therapy, the decline of IL-6 was seen only in MTX responders but not in non-responders. Pre-treatment serum levels did not predict future MTX response or non-response. IL-6 levels also correlated weakly but significantly with disease activity. Serial measurement of serum IL-6 merits further exploration in larger studies as a potential biomarker of MTX response in RA. Disclosure S. Jain: None. V. Dhir: None. A. Aggarwal: None. R. Gupta: None. S. Maurya: None. B. Leishangthem: None. A. Khullar: None. S. Naidu: None. S.K. Sharma: None. A. Sharma: None. S. Jain: None.

Hsa_circ_0056856 in the serum serves as a potential novel biomarker for disease activity in psoriasis.

hsa_circ_0056856 in the serum serves as a potential novel biomarker for disease activity in psoriasis.

Serum levels of fetuin-A as a novel biomarker for disease activity in patients with Takayasu arteritis and granulomatous polyangiitis.

The aim of the present study was to investigate serum fetuin-A (Fet-A) levels in patients with Takayasu arteritis (TA) and granulomatous polyangiitis (GPA) and to analyze the relationship between serum Fet-A levels and disease activity scores. Thirty-two TA and 28 GPA patients presented to the rheumatology clinic at Gazi University and met the criteria of American College of Rheumatology 1990 and 2012 International Chapell Hill meeting, respectively, and 20 healthy control subjects were included in the present study. We collected data on serum C-reactive protein (CRP), albumin, calcium, and phosphate levels as well as erythrocyte sedimentation rates. Calcification risk index (CRI) was calculated for each patient. The Birmingham Vasculitis Activity Score (BVAS) and Indian Takayasu Clinical Activity Score (ITAS), were used to assess disease activity in GPA and TA patients respectively. Serum Fet-A levels were significantly lower in the overall vasculitis group compared to control group (p = 0.015). In subgroup analysis, Fet-A levels were significantly lower in those with active disease, compared to control group (p = 0.001, for active TA (n = 18) and GPA (n = 17), respectively). However, there was no significant difference in serum Fet-A levels in inactive cases versus control subjects (p = 0.061, for inactive TA (n = 14) and GPA (n = 11), respectively). Serum Fet-A levels negatively correlated with BVAS (r = - 0.675) and ITAS scores (r = - 0.385), as well as with CRP and CRI. Our results suggest that serum Fet-A level could be a novel biomarker for assessment of activity status in patients with GPA or TA. Key Points • Serum Fetuin-A is negative acute phase protein and systemic calcification inhibitor synthesized in hepatocytes and secreted by various inflammation. • Serum Fetuin-A was negatively correlated with CRP, BVAS, and ITAS scores and significantly decreased in vasculitis patients with high disease activity. • Serum Fetuin-A could be a promising and useful biomarker for the assessment of disease activity for vasculitis, also that it might also be a predictor of long-term cardiovascular progression.

Integrative Analysis of the Inflammatory Bowel Disease Serum Metabolome Improves Our Understanding of Genetic Etiology and Points to Novel Putative Therapeutic Targets

Polygenic and environmental factors are underlying causes of inflammatory bowel disease (IBD). We hypothesized that integration of the genetic loci controlling a metabolite's abundance, with known IBD genetic susceptibility loci, may help resolve metabolic drivers of IBD. We measured the levels of 1300 metabolites in the serum of 484 patients with ulcerative colitis (UC) and 464 patients with Crohn's disease (CD) and 365 controls. Differential metabolite abundance was determined for disease status, subtype, clinical and endoscopic disease activity, as well as IBD phenotype including disease behavior, location, and extent. To inform on the genetic basis underlying metabolic diversity, we integrated metabolite and genomic data. Genetic colocalization and Mendelian randomization analyses were performed using known IBD risk loci to explore whether any metabolite was causally associated with IBD. We found 173 genetically controlled metabolites (metabolite quantitative trait loci, 9 novel) within 63 non-overlapping loci (7 novel). Furthermore, several metabolites significantly associated with IBD disease status and activity as defined using clinical and endoscopic indexes. This constitutes a resource for biomarker discovery and IBD biology insights. Using this resource, we show that a novel metabolite quantitative trait locus for serum butyrate levels containing ACADS was not supported as causal for IBD; replicate the association of serum omega-6 containing lipids with the fatty acid desaturase 1/2 locus and identify these metabolites as causal for CD through Mendelian randomization; and validate a novel association of serum plasmalogen and TMEM229B, which was predicted as causal for CD. An exploratory analysis combining genetics and unbiased serum metabolome surveys can reveal novel biomarkers of disease activity and potential mediators of pathology in IBD.

Calprotectin in Chronic Inflammatory Demyelinating Polyneuropathy and Variants-A Potential Novel Biomarker of Disease Activity.

Background: In chronic inflammatory demyelinating polyneuropathy (CIDP), there is an urgent need for biomarkers to monitor ongoing disease activity. Serum calprotectin (CLP) induces signaling pathways involved in inflammatory processes and has been shown to correlate with markers of disease activity in other autoimmune disorders. Thus, we wanted to study the potential value of CLP in comparison to serum neurofilament light chain (sNfl) to monitor disease activity.Materials and Methods: Sera from 63 typical and atypical CIDP and 6 MMN patients with varying degrees of disease activity were analyzed in comparison with 40 healthy controls (HC) in a cross-sectional design. Association of CLP and sNfl levels with socio-demographics, disease duration, CIDP disease activity scale (CDAS), and impairment status [medical research council-sum score (MRC-SS), the inflammatory neuropathy cause and treatment disability score (INCAT-DS), grip strength, and maximum walking distance], patient-reported outcome (PRO) parameters [SF-36 questionnaire, Beck's depression index (BDI), and fatigue severity scale (FSS)], as well as treatment regime were investigated using uni- and multivariate analysis.Results: CLP and sNfl levels were significantly higher in all CIDP patients compared to HC (p = 0.0009). Multivariate analysis adjusted for age and gender revealed that CLP acts as an independent predictor for CIDP and MMN. CLP was significantly associated with active disease course according to CDAS and correlated with MRC-SS, whereas sNfl correlated with parameters of disease impairment. There was no correlation with PRO, except for sNfl and the mental health composite score. Subgroup analysis revealed no differences between typical CIDP and atypical variants.Conclusions: CLP was elevated in CIDP and variants and was associated with active disease course, whereas sNfl shows further potential as biomarker of axonal degeneration. Thus, CLP might be a suitable additive biomarker for measurement of ongoing inflammation, which is greatly needed to guide better patient care in CIDP.

Fc Glycosylation Characterization of Human Immunoglobulins G Using Immunocapture and LC-MS.

Immunoglobulins G (IgG) are proteins produced by the immune system of higher life forms that play a central role in the defense against microbial pathogens. IgG bind pathogens with the hypervariable Fab component and mediate a diversity of effector functions by binding to immune effector cells via their crystallizable (Fc) component. All IgG Fc carry a polymorphic N-glycan that regulates its binding properties and thereby its effector functions. The glycosylation profile of IgG Fc is modulated by physiological and pathological conditions, including infectious diseases and inflammatory disorders. Characterization of IgG Fc glycosylation profiles is a promising approach to understand the pathogenesis of diseases involving the immune system and to develop novel biomarkers of disease activity. Measuring the proportion of the different IgG Fc glycoforms remains an analytical challenge, that requires a sensitive and reproducible analytical approach.This chapter describes an optimized approach for the preparation and the analysis of Fc N-glycans from total serum or plasma IgG using magnetic beads, RapiFluor MS label©, and LC-MS.

CD14 (C-159T) polymorphism is associated with increased susceptibility to SLE, and plasma levels of soluble CD14 is a novel biomarker of disease activity: A hospital-based case-control study.

Cluster of differentiation 14 (CD14) plays a crucial role in the innate immune response of the host in protection against various pathogens. The importance of soluble CD14 in autoimmune disorders has been described in different populations. However, the role of sCD14 in systemic lupus erythematosus (SLE) is poorly understood. Further, the association of functional variants at the promoter region of the CD14 gene (-159 C > T) with susceptibility to SLE or disease severity needs to be defined. Two hundred female SLE patients diagnosed on systemic lupus international collaborating clinics (SLICC) classification criteria and age, sex, matched healthy controls were enrolled in the present study. Polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method was used to genotype CD14 (C-159 T) polymorphism. Plasma levels of IFN-α, TNF-α, and sCD14 were quantified by enzyme-linked immunosorbent assay (ELISA). Prevalence of mutant genotypes (CT and TT) and minor allele (T) of CD14 (C-159T) polymorphism was significantly higher in SLE cases compared to healthy controls (CT: P < 0.0001; OR = 3.26, TT:P < 0.0001; OR = 3.39; T:P = 0.0009, OR = 1.62). Further, lupus nephritis patients had a higher prevalence of homozygous mutants (TT) and mutant allele (T)(TT: P = 0.0002, OR = 8.07; T: P = 0.001, OR = 1.32). SLE patients displayed significantly increased plasma sCD14, TNF-α, and IFN-α levels in comparison to healthy controls. These cytokines were significantly elevated in patients of lupus nephritis compared to those without kidney involvement. Interestingly, sCD14 levels correlated positively with SLE disease activity index-2K (SLEDAI-2K) scores and 24 hours proteinuria. CD14 (C-159T) polymorphism is associated with an increased predisposition to the development of SLE and lupus nephritis: sCD14 is a promising novel biomarker for assessing disease activity and lupus nephritis.

Milk fat globule epidermal growth factor 8 (MFG-E8) on monocytes is a novel biomarker of disease activity in systemic lupus erythematosus.

Milk fat globule epidermal growth factor (MFG-E8) is related secreted protein which links phosphatidylserine on apoptotic cells and integrin αvβ3/5 on phagocytes. To clarify the clinical significance of MFG-E8 in SLE, we analyzed the correlation between expression level of MFG-E8 in circulating phagocytic leukocytes and clinical parameters of patients. The study was conducted under a multi-center, prospective cohort design. Patients with one or both BILAG A or B, or SLEDAI- 2 K ≥ 4 with clinical symptoms were defined as the active SLE group. Expression of MFG-E8 on monocytes and concentration in serum were measured by FACS and ELISA, respectively. 96 subjects were enrolled. The absolute number and proportion of MFG-E8-positive monocytes to total monocytes were significantly higher in the active SLE group (p < 0.01). Importantly, the proportion was also significantly correlated with SLEDAI-2K, clinical SLEDAI, as well as serum levels of anti-ds-DNA antibody and complement and C1q. In addition, the proportion of MFG-E8-positive monocytes to total monocytes was significantly decreased from baseline in active SLE patients after 6 months' treatment and increased concordantly with disease activity in 6 refractory cases. Further, in receiver operating characteristic curve analysis for discrimination between active and inactive SLE, the AUC of the proportion of MFG-E8 was 0.854, which was equivalent to classical activity markers such as anti-ds DNA antibody (0.776), complement (0.897) and C1q (0.815). The proportion of MFG-E8-positive monocytes to total monocytes in peripheral blood was positively associated with disease activity in SLE and may be a novel biomarker of disease activity.

Comment on: Serum sTREM-1 in adult-onset Still's disease: a novel biomarker of disease activity and a potential predictor of the chronic course: reply.

Comment on: Serum sTREM-1 in adult-onset Still's disease: a novel biomarker of disease activity and a potential predictor of the chronic course: reply.

Comment on: Serum Strem-1 in adult-onset Still's disease: a novel biomarker of disease activity and a potential predictor of the chronic course.

Comment on: Serum Strem-1 in adult-onset Still's disease: a novel biomarker of disease activity and a potential predictor of the chronic course.

Serum level of soluble urokinase plasminogen activator receptor (suPAR) as a disease severity marker of myasthenia gravis: a pilot study.

Myasthenia gravis (MG) is an autoantibody-mediated inflammatory disease of the neuromuscular junction. Biomarkers indicating disease activity in MG are warranted. Recently, the soluble urokinase plasminogen activator receptor (suPAR) has been reported to be associated with inflammation, tissue damage, disease activity and prognosis in various diseases, including autoimmune diseases. In this study, serum suPAR levels were measured in 40patients with anti-acetylcholine receptor antibody-positive MG and 30controls, and their correlations with clinical variables and severity scale scores were investigated. We identified that serum suPAR levels significantly correlated with MG activities of daily living scale (Spearman's ρ=0·45; P=0·004) and MG Foundation of America classification (Spearman's ρ=0·37; P=0·02) at serum sampling, but not with anti-acetylcholine receptor antibody titers. In conclusion, serum suPAR levels can be a candidate for a novel biomarker of disease activity in anti-acetylcholine receptor antibody-positive MG.