Levels of soluble TNF-RII are increased in serum of patients with primary progressive multiple sclerosis

Quantile-Specific Heritability of Inflammatory and Oxidative Stress Biomarkers Linked to Cardiovascular Disease

PURPOSE

Heritability (h2 , the proportion of the phenotypic variance attributable to additive genetic effects) is traditionally assumed to be constant throughout the distribution of the phenotype. However, the heritabilities of circulating C-reactive protein, interleukin-6, plasminogen activator inhibitor type-1 (PAI-1), and monocyte chemoattractant protein-1 (MCP-1) concentrations depend upon whether the phenotype is high or low relative to their distributions (quantile-dependent expressivity), which may account for apparent gene-environment interactions. Whether the heritabilities of other inflammatory biomarkers linked to cardiovascular disease are quantile-dependent remain to be determined.

PATIENTS AND METHODS

Quantile-specific offspring-parent (βOP) and full-sib regression slopes (βFS) were estimated by applying quantile regression to the age- and sex-adjusted phenotypes of families surveyed as part of the Framingham Heart Study. Quantile-specific heritabilities were calculated as: h2 =2βOP/(1+rspouse) and h2 ={(1+8rspouseβFS)0.5-1}/(2rspouse).

RESULTS

Heritability (h2 ± SE) of lipoprotein-associated phospholipase A2 (Lp-PLA2) mass concentrations increased from 0.11 ± 0.03 at the 10th percentile, 0.08 ± 0.03 at the 25th, 0.12 ± 0.03 at the 50th, 0.20 ± 0.04 at the 75th, and 0.26 ± 0.06 at the 90th percentile, or 0.0023 ± 0.0006 per each one-percent increase in the phenotype distribution (Plinear trend= 0.0004). Similarly, h2 increased 0.0029 ± 0.0011 (Plinear trend= 0.01) for sP-selectin, 0.0032 ± 0.0009 (Plinear trend= 0.0001) for soluble intercellular adhesion molecule 1 (sICAM-1), and 0.0026 ± 0.0006 for tumor necrosis factor receptor 2 (TNFR2) (Plinear trend= 5.0 × 10-6) per each one-percent increase in their distributions when estimated from βOP. Osteoprotegerin and soluble ST2 heritability also increased significantly with increasing percentiles of their distributions when estimated from βFS. Lp-PLA2 activity, CD40 ligand, TNFα, interleukin-18, and myeloperoxidase heritability showed no significant quantile-dependence.

CONCLUSION

The heritabilities of circulating Lp-PLA2-mass, sP-selectin, sICAM-1, TNFR2, osteoprotegerin and soluble ST2 concentrations are quantile-dependent, which may contribute to purported genetic modulations of: 1) sP-selectin's relationships to venous thrombosis, pulmonary hypertension, type 2 diabetes and atorvastatin treatment; 2) sICAM-I's relationships to brain abscess and atorvastatin treatment; and 3) Lp-PLA2's relationships to myocardial infarction and preeclampsia.

Antioxidant and Anti-inflammatory Diagnostic Biomarkers in Multiple Sclerosis: A Machine Learning Study

An imbalance of inflammatory/anti-inflammatory and oxidant/antioxidant molecules has been implicated in the demyelination and axonal damage in multiple sclerosis (MS). The current study aimed to evaluate the plasma levels of tumor necrosis factor (TNF)-α, soluble TNF receptor (sTNFR)1, sTNFR2, adiponectin, hydroperoxides, advanced oxidation protein products (AOPP), nitric oxide metabolites, total plasma antioxidant capacity using the total radical-trapping antioxidant parameter (TRAP), sulfhydryl (SH) groups, as well as serum levels of zinc in 174 MS patients and 182 controls. The results show that MS is characterized by lowered levels of zinc, adiponectin, TRAP, and SH groups and increased levels of AOPP. MS was best predicted by a combination of lowered levels of zinc, adiponectin, TRAP, and SH groups yielding an area under the receiver operating characteristic (AUC/ROC) curve of 0.986 (±0.005). The combination of these four antioxidants with sTNFR2 showed an AUC/ROC of 0.997 and TRAP, adiponectin, and zinc are the most important biomarkers for MS diagnosis followed at a distance by sTNFR2. Support vector machine with tenfold validation performed on the four antioxidants showed a training accuracy of 92.9% and a validation accuracy of 90.6%. The results indicate that lowered levels of those four antioxidants are associated with MS and that these antioxidants are more important biomarkers of MS than TNF-α signaling and nitro-oxidative biomarkers. Adiponectin, TRAP, SH groups, zinc, and sTNFR2 play a role in the pathophysiology of MS, and a combination of these biomarkers is useful for predicting MS with high sensitivity, specificity, and accuracy. Drugs that increase the antioxidant capacity may offer novel therapeutic opportunities for MS.

Tumor necrosis factor alpha (TNF-α) and its soluble receptors are associated with disability, disability progression and clinical forms of multiple sclerosis

BACKGROUND

The association between tumor necrosis factor (TNF)-α, soluble TNF receptor (sTNFR)1 and sTNFR2 with clinical characteristics of multiple sclerosis (MS) remains unclear.

OBJECTIVE

To examine whether TNF-α, sTNFR1 and sTNFR2 are associated with MS diagnosis, disability, disability progression and clinical forms of MS.

MATERIALS AND SUBJECTS

The study included 147 patients with relapsing-remitting MS (RRMS), 21 with progressive clinical forms (ProgMS) and 70 controls. Expanded Disability Status Scale (EDSS) evaluated disability as mild (EDSS < 3.0) or moderate/high (EDSS ≥ 3.0). Multiple Sclerosis Severity Score (MSSS) evaluated disability progression as no progression (MSSS < 5) and progression (MSSS ≥ 5). Baseline data of subjects and plasma levels of TNF-α, sTNFR1, sTNFR2 were obtained.

RESULTS

The MS diagnosis explained 44.6% and 12.3% of TNF-α and sTNFR2 levels, respectively. Moderate/high disability and disability progression were best predicted by sTNFR1 and age (positively) and ProgMS were best predicted by sTNFR1 (positively) and sTNFR2 (negatively), coupled with age and sex. A composite score reflecting the sTNFR1/sTNFR2 ratio showed a positive association with ProgMS after adjusting for age and sex.

CONCLUSION

Increased sTNFR1 and age were positively associated with disability and disability progression, whereas increased sTNFR1 (positively) and sTNFR2 (negatively) were associated with ProgMS, suggesting a distinct role of them in the immunopathological mechanisms of MS.

Potential role of soluble TNF-α receptors in diagnosis of idiopathic membranous nephropathy

Soluble tumor necrosis factor alpha (TNF-α) receptors contain two receptors: soluble tumor necrosis factor receptor (sTNFR) 1 and 2, and the aim of our study was to discover their concentration and diagnostic value for idiopathic membranous nephropathy (IMN). In total, 58 patients with IMN, 51 patients with chronic kidney disease (CKD), and 30 healthy volunteers were enrolled in this study. Levels of serum sTNFR1 and sTNFR2 were determined by enzyme-linked immunosorbent assay (ELISA). Serum cystatin C (CysC), urea, creatinine (CREA), uric acid (UA), total protein (TP), albumin (ALB), and 24-h urinary protein (proteinuria, PRO) were examined by automatic biochemical analyzer. Levels of sTNFR1 and sTNFR2 were significantly higher in IMN group than CKD and control group ( P < 0.05). In IMN group, there were significant correlation between sTNFR1 and sTNFR2 ( P < 0.01). Both sTNFR1 and sTNFR2 were positively related to serum urea, CREA, CysC, UA, 24-h PRO ( P < 0.05) and negatively related to ALB ( P < 0.01). Receiver operating characteristic (ROC) analysis showed that the area under the curve (AUC) of sTNFR1 and sTNFR2 were 0.997 and 0.993, respectively, when control was healthy volunteers. When sTNFR1 cut-off was 959.15 pg/mL, the sensitivity and specificity were 96.6% and 100%, respectively. When sTNFR2 cut-off was 2449.43 pg/mL, the sensitivity and specificity were 93.1% and 100%, respectively. While the control was CKD group, AUC of sTNFR1 and sTNFR2 were 0.647 and 0.626, respectively. When sTNFR1 cut-off was 3356.57 pg/mL, the sensitivity and specificity were 72.4% and 60.8%, respectively. When sTNFR2 cut-off was 6497.34 pg/mL, the sensitivity and specificity were 72.4% and 58.8%, respectively. This is the first study to show that both levels of sTNFR1 and sTNFR2 increased and correlated with serum urea, CREA, CysC, UA, ALB, 24-h PRO and could be usable for IMN diagnosis and differential diagnosis between IMN and CKD.

Antibody-Array-Based Proteomic Screening of Serum Markers in Systemic Lupus Erythematosus: A Discovery Study

A discovery study was carried out where serum samples from 22 systemic lupus erythematosus (SLE) patients and matched healthy controls were hybridized to antibody-coated glass slide arrays that interrogated the level of 274 human proteins. On the basis of these screens, 48 proteins were selected for ELISA-based validation in an independent cohort of 28 SLE patients. Whereas AXL, ferritin, and sTNFRII were significantly elevated in patients with active lupus nephritis (LN) relative to SLE patients who were quiescent, other molecules such as OPN, sTNFRI, sTNFRII, IGFBP2, SIGLEC5, FAS, and MMP10 exhibited the capacity to distinguish SLE from healthy controls with ROC AUC exceeding 90%, all with p < 0.001 significance. These serum markers were next tested in a cohort of 45 LN patients, where serum was obtained at the time of renal biopsy. In these patients, sTNFRII exhibited the strongest correlation with eGFR (r = -0.50, p = 0.0014) and serum creatinine (r = 0.57, p = 0.0001), although AXL, FAS, and IGFBP2 also correlated with these clinical measures of renal function. When concurrent renal biopsies from these patients were examined, serum FAS, IGFBP2, and TNFRII showed significant positive correlations with renal pathology activity index, while sTNFRII displayed the highest correlation with concurrently scored renal pathology chronicity index (r = 0.57, p = 0.001). Finally, in a longitudinal cohort of seven SLE patients examined at ∼3 month intervals, AXL, ICAM-1, IGFBP2, SIGLEC5, sTNFRII, and VCAM-1 demonstrated the ability to track with concurrent disease flare, with significant subject to subject variation. In summary, serum proteins have the capacity to identify patients with active nephritis, flares, and renal pathology activity or chronicity changes, although larger longitudinal cohort studies are warranted.

Peripheral blood biomarkers in multiple sclerosis

Multiple sclerosis is the most common autoimmune disorder affecting the central nervous system. The heterogeneity of pathophysiological processes in MS contributes to the highly variable course of the disease and unpredictable response to therapies. The major focus of the research on MS is the identification of biomarkers in biological fluids, such as cerebrospinal fluid or blood, to guide patient management reliably. Because of the difficulties in obtaining spinal fluid samples and the necessity for lumbar puncture to make a diagnosis has reduced, the research of blood-based biomarkers may provide increasingly important tools for clinical practice. However, currently there are no clearly established MS blood-based biomarkers. The availability of reliable biomarkers could radically alter the management of MS at critical phases of the disease spectrum, allowing for intervention strategies that may prevent evolution to long-term neurological disability. This article provides an overview of this research field and focuses on recent advances in blood-based biomarker research.