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Objectives: In this study, we measured serum interferon (IFN) levels and activity in patients with sarcoidosis and tuberculosis (TB) with and without uveitis. We aimed to understand the role of IFN in the pathophysiology of both conditions and explore its potential as a discriminating marker for these clinically similar diseases. Methods: Sera from an Indonesian TB and a Dutch sarcoidosis cohort were used in the analysis. IFNα2 and IFNγ concentrations were measured using Simoa® and Luminex assays, respectively. Serum IFN activity was assessed by incubating THP-1 cells with patient serum and measuring IFN-stimulated gene transcription using qPCR. Anti-IFNα2 and IFNγ autoantibodies were detected via Luminex assay and tested for neutralizing capacity using a flow cytometry-based signal transducer and activator of transcription (STAT) 1 phosphorylation inhibition assay. Results: IFNα2 was detected in 74 % and 64 % of patients with sarcoidosis and pulmonary TB, respectively, while IFNγ was found in 78 % and 23 % of patients with sarcoidosis and TB, respectively. For uveitis cases specifically, IFNα2 was detected in 85 % of sarcoid uveitis (SU) and 33 % of tubercular uveitis (TBU) cases. Similarly, IFNγ was detected in 69 % of SU and 17 % of TBU cases. IFNγ serum concentrations were higher in sarcoidosis than that in TB patients (p

Summary: Background: X-linked adrenoleukodystrophy (X-ALD) is highly variable, ranging from slowly progressive adrenomyeloneuropathy to severe brain demyelination and inflammation (cerebral ALD, CALD) affecting males with childhood peak onset. Risk models integrating blood-based biomarkers to indicate CALD onset, enabling timely interventions, are lacking. Therefore, we evaluated the prognostic value of blood biomarkers in addition to current neuroimaging predictors for early detection of CALD. Methods: We measured blood biomarkers in a retrospective, male CALD risk-assessment cohort consisting of 134 X-ALD patients and 66 controls and in a phenotype-blinded validation set (25 X-ALD boys, 4–13 years) using Simoa®and Luminex® technologies. Findings: Among 25 biomarkers indicating axonal damage, astrocye/microglia activation, or immune-cell recruitment, neurofilament light chain (NfL) had the highest prognostic value for early indication of childhood/adolescent CALD. A plasma NfL cut-off level of 8.33 pg/mL, determined in the assessment cohort, correctly discriminated CALD with an accuracy of 96% [95% CI: 80–100] in the validation group. Multivariable logistic regression models revealed that combining NfL with GFAP or cytokines/chemokines (IL-15, IL-12p40, CXCL8, CCL11, CCL22, and IL-4) that were significantly elevated in CALD vs healthy controls had no additional benefit for detecting neuroinflammation. Some cytokines/chemokines were elevated only in childhood/adolescent CALD and already upregulated in asymptomatic X-ALD children (IL-15, IL-12p40, and CCL7). In adults, NfL levels distinguished CALD but were lower than in childhood/adolescent CALD patients with similar (MRI) lesion severity. Blood GFAP did not differentiate CALD from non-inflammatory X-ALD. Interpretation: Biomarker-based risk prediction with a plasma NfL cut-off value of 8.33 pg/mL, determined by ROC analysis, indicates CALD onset with high sensitivity and specificity in childhood X-ALD patients. A specific pro-inflammatory cytokine/chemokine profile in asymptomatic X-ALD boys may indicate a primed, immanent inflammatory state aligning with peak onset of CALD. Age-related differences in biomarker levels in adult vs childhood CALD patients warrants caution in predicting onset and progression of CALD in adults. Further evaluations are needed to assess clinical utility of the NfL cut-off for risk prognosis of CALD onset. Funding: Austrian Science Fund, European Leukodystrophy Association.

BackgroundDiabetic sensorimotor polyneuropathy (DSPN) is one of the most prevalent and poorly understood diabetic microvascular complications. Recent studies have found that fractional anisotropy (FA), a marker for microstructural nerve integrity, is a sensitive parameter for the structural and functional nerve damage in DSPN. The aim of this study was to investigate the significance of proximal sciatic nerve’s FA on different distal nerve fiber deficits of the upper and lower limbs and its correlation with the neuroaxonal biomarker, neurofilament light chain protein (NfL).Materials and methodsSixty-nine patients with type 2 diabetes (T2DM) and 30 healthy controls underwent detailed clinical and electrophysiological assessments, complete quantitative sensory testing (QST), and diffusion-weighted magnetic resonance neurography of the sciatic nerve. NfL was measured in the serum of healthy controls and patients with T2DM. Multivariate models were used to adjust for confounders of microvascular damage.ResultsPatients with DSPN showed a 17% lower sciatic microstructural integrity compared to healthy controls (p

Elevated levels of saturated very long-chain fatty acids (VLCFAs) in cell membranes and secreted lipoparticles have been associated with neurotoxicity and, therefore, require tight regulation. Excessive VLCFAs are imported into peroxisomes for degradation by β-oxidation. Impaired VLCFA catabolism due to primary or secondary peroxisomal alterations is featured in neurodegenerative and neuroinflammatory disorders such as X-linked adrenoleukodystrophy and multiple sclerosis (MS). Here, we identified that healthy human macrophages upregulate the peroxisomal genes involved in β-oxidation during myelin phagocytosis and pro-inflammatory activation, and that this response is impaired in peripheral macrophages and phagocytes in brain white matter lesions in MS patients. The pharmacological targeting of VLCFA metabolism and peroxisomes in innate immune cells could be favorable in the context of neuroinflammation and neurodegeneration. We previously identified the epigenetic histone deacetylase (HDAC) inhibitors entinostat and vorinostat to enhance VLCFA degradation and pro-regenerative macrophage polarization. However, adverse side effects currently limit their use in chronic neuroinflammation. Here, we focused on tefinostat, a monocyte/macrophage-selective HDAC inhibitor that has shown reduced toxicity in clinical trials. By using a gene expression analysis, peroxisomal β-oxidation assay, and live imaging of primary human macrophages, we assessed the efficacy of tefinostat in modulating VLCFA metabolism, phagocytosis, chemotaxis, and immune function. Our results revealed the significant stimulation of VLCFA degradation with the upregulation of genes involved in peroxisomal β-oxidation and interference with immune cell recruitment; however, tefinostat was less potent than the class I HDAC-selective inhibitor entinostat in promoting a regenerative macrophage phenotype. Further research is needed to fully explore the potential of class I HDAC inhibition and downstream targets in the context of neuroinflammation.

This study compared two 96-well multiplex immunoassay platforms for analytical performance in assessing cytokine concentrations in standards, quality controls and human plasma samples (n = 62), and evaluated assay time requirements. Assays included a bead-based fluorescence MILLIPLEX® assay/Luminex fluorescence platform (LMX) and three kits from Meso Scale Discovery (MSD) in planar electrochemiluminescence format. The LMX kit evaluated 21 cytokines and the MSD kits evaluated 10 cytokines each, with 16 overlapping cytokines between platforms. Both assays provided good reproducibility in standard curves for all analytes. Interassay CVs of shared analytes showed average kit quality control CVs ranging 1.9–18.2% for LMX and 2.4–13.9% for MSD. The MSD platform had lower LLoQs than LMX for 14/16 shared cytokines. For IL-17, the LLoQ was lower with LMX than MSD, and the LLoQs for IL-6 were similar. Although MSD calibration curves indicated lower LLoQs for most of those analytes, many more cytokines in human plasma samples were not detected by MSD than by LMX. The ULoQs were higher in LMX versus MSD assays for 13/16 shared analytes, lower than MSD for IL-17, and equivalent between assays for IL-6 and MIP-1α. Bland-Altman plots indicated that MSD classified 13/16 shared analytes as concentrations lower than by LMX. Time and motion analysis indicated that total mean assay times were 20 h 28 m and 21 h 33 m for LMX and MSD, respectively, including an overnight (17 h) incubation. The MSD assays employed a manufacturer-approved overnight incubation instead of the standard 2-h incubation, which kit instructions suggest might increase detection sensitivity. Hands-on labor time averaged 1 h 37 m for LMX and 2 h 33 m for MSD. In summary, assay selection factors should include selection of specific markers of interest, time and cost considerations, and anticipated cytokine concentrations in prospective samples.