CORRECTION article Front. Lupus, 04 June 2024Sec. Clinical Research and Treatment in Lupus Volume 2 - 2024 | https://doi.org/10.3389/flupu.2024.1432884
Despite rigorous confirmation with reliable assays, some individuals showing the neuromyelitis optica spectrum disorder (NMOSD) phenotype remain negative for both aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibodies.We aimed to investigate whether double seronegative NMOSD (DN-NMOSD) and NMOSD with AQP4 antibody (AQP4-NMOSD) share the same pathophysiological basis, astrocytopathy, by measurement of cerebrospinal fluid (CSF) glial fibrillary acidic protein (GFAP) levels as a marker of astrocyte damage.Seventeen participants who (1) satisfied the 2015 diagnostic criteria for NMOSD, and (2) tested negative for AQP4 and MOG antibodies confirmed with repeated cell-based assays, and (3) had available CSF samples obtained at the point of clinical attacks, were enrolled from 4 medical centers (South Korea, Germany, Thailand, and Denmark). Thirty age-matched participants with AQP4-NMOSD, 17 participants with MOG antibody associated disease (MOGAD), and 15 participants with other neurological disorders (OND) were included as controls. The concentration of CSF GFAP was measured using enzyme-linked immunosorbent assay.CSF GFAP levels in the DN-NMOSD group were significantly lower than those in the AQP4-NMOSD group (median: 0.49 versus 102.9 ng/mL; p < 0.001), but similar to those in the OND (0.25 ng/mL) and MOGAD (0.39 ng/mL) control groups. The majority (90% (27/30)) of participants in the AQP4-NMOSD group showed significantly higher CSF GFAP levels than the highest level measured in the OND group, while no participant in the DN-NMOSD and MOGAD groups did.These results suggest that DN-NMOSD has a different underlying pathogenesis other than astrocytopathy, distinct from AQP4-NMOSD.
Passive and active immunization with α-synuclein has been shown to be neuroprotective in animal models of Parkinson's disease. We have previously shown that vaccination with α-synuclein, long before α-synuclein-induced brain pathology, prevents striatal degeneration by inducing regulatory T cell infiltration in parenchyma and antibody deposition on α-synuclein overexpressing neurons. However, the effect of peripheral α-synuclein on the immune system is unknown, as are the mechanistic changes induced in the CD4 T cell population during successful neuroprotective animal studies. We have studied the changes induced by vaccination with α-synuclein in the CD4 T cell pool and its impact on brain microglia to understand the immune mechanisms behind successful vaccination strategies in Parkinson's disease animal models. Mice were immunized with WT or nitrated α-synuclein at a dose equivalent to the one used in our previous successful vaccination strategy and at a higher dose to determine potential dose-dependent effects. Animals were re-vaccinated 4 weeks after and sacrificed 5 days later. These studies were conducted in naive animals in the absence of human α-synuclein expression. The CD4 T cell response was modulated by α-synuclein in a dose-dependent manner, in particular the regulatory T cell population. Low-dose α-synuclein induced expansion of naive (Foxp3 + CCR6-CD127lo/neg) and dopamine receptor type D3+ regulatory T cells, as well as an increase in Stat5 protein levels. On the other hand, high dose promoted activation of regulatory T cells (Foxp3CCR6 + CD127lo/neg), which were dopamine receptor D2+D3-, and induced up-regulation of Stat5 and production of anti-α-synuclein antibodies. These effects were specific to the variant of α-synuclein used as the pathology-associated nitrated form induced distinct effects at both doses. The changes observed in the periphery after vaccination with low-dose α-synuclein correlated with an increase in CD154+, CD103+, and CD54+ microglia and the reduction of CD200R+ microglia. This resulted in the induction of a polarized tolerogenic microglia population that was CD200R-CD54CD103CD172a+ (82 % of total microglia). We have shown for the first time the mechanisms behind α-synuclein vaccination and, importantly, how we can modulate microglia's phenotype by regulating the CD4 T cell pool, thus shedding invaluable light on the design of neuroimmunoregulatory therapies for Parkinson's disease.
Long-term outcome in multiple sclerosis (MS) depends on early treatment. In patients with acute optic neuritis (ON), an early inflammatory event, we investigated markers in cerebrospinal fluid (CSF), which may predict a diagnosis of MS. Forty patients with acute ON were recruited in a prospective population-based cohort with median 29 months (range 19–41) of follow-up. Paired CSF and serum samples were taken within 14 days (range 2–38), prior to treatment. Prospectively, 16/40 patients were by a uniform algorithm diagnosed with MS (MS-ON) and 24 patients continued to manifest isolated ON (ION) during follow-up. Levels of cytokines and neurofilament light chain (NF-L) were measured at the onset of acute ON and compared to healthy controls (HC). Significance levels were corrected for multiple comparisons ("q"). The predictive value of biomarkers was determined with multivariable prediction models using nomograms. CSF TNF-α, IL-10, and CXCL13 levels were increased in MS-ON compared to those in ION patients (q = 0.021, 0.004, and 0.0006, respectively). MS-ON patients had increased CSF pleocytosis, IgG indices, and oligoclonal bands (OCBs) compared to ION (q = 0.0007, q = 0.0058, and q = 0.0021, respectively). CSF levels of IL-10, TNF-a, IL-17A, and CXCL13 in MS-ON patients correlated with leukocyte counts (r > 0.69 and p < 0.002) and IgG index (r > 0.55, p < 0.037). CSF NF-L levels were increased in ON patients compared to those in HC (q = 0.0077). In MS-ON, a progressive increase in NF-L levels was observed at 7 to 14 days after disease onset (r = 0.73, p < 0.0065). Receiver-operating characteristic (ROC) curves for two multivariable prediction models were generated, with IL-10, CXCL13, and NF-L in one ("candidate") and IgG index, OCB, and leukocytes in another ("routine"). Area under the curve was 0.89 [95% CI 0.77–1] and 0.86 [0.74–0.98], respectively. Predictions of the risk of MS diagnosis were illustrated by two nomograms. CSF TNF-α, IL-10, CXCL13, and NF-L levels were associated with the development of MS, suggesting that the inflammatory and neurodegenerative processes occurred early. Based on subsequent diagnosis, we observed a high predictive value of routine and candidate biomarkers in CSF for the development of MS in acute ON. The nomogram predictions may be useful in the diagnostic work-up of MS.
Background: Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein not previously described in the human central nervous system (CNS). Objectives: We determined MFAP4 CNS expression and measured cerebrospinal fluid (CSF) and serum levels. Methods: Tissue was sampled at autopsy from patients with acute multiple sclerosis (MS) ( n = 3), progressive MS ( n = 3), neuromyelitis optica spectrum disorder (NMOSD) ( n = 2), and controls ( n = 9), including 6 healthy controls (HC). MFAP4 levels were measured in 152 patients: 49 MS, 62 NMOSD, 22 myelin oligodendrocyte glycoprotein-associated disease (MOGAD), and 19 isolated optic neuritis (ION). Results: MFAP4 localized to meninges and vascular/perivascular spaces, intense in the optic nerve. At sites of active inflammation, MFAP4 reactivity was reduced in NMOSD and acute MS and less in progressive MS. CSF MFAP4 levels were reduced during relapse and at the onset of diseases (mean U/mL: MS 14.3, MOGAD 9.7, and ION 14.6 relative to HC 17.9. ( p = 0.013, p = 0.000, and p = 0.019, respectively). Patients with acute ON ( n = 68) had reduced CSF MFAP4 (mean U/mL: 14.5, p = 0.006). CSF MFAP4 levels correlated negatively with relapse severity (rho = −0.41, p = 0.017). Conclusion: MFAP4 immunoreactivity was reduced at sites of active inflammation. CSF levels of MFAP4 were reduced following relapse and may reflect disease activity.
Abstract Background and Objectives: Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein not previously described in the central nervous system (CNS). We aimed to determine MFAP4 CNS expression and measure cerebrospinal fluid (CSF) and serum levels. Methods : Tissue was sampled at autopsy from patients with acute multiple sclerosis (MS) (n=3), progressive MS (n=3), neuromyelitis optica spectrum disorder (NMOSD) (n=2), controls (n=9), including 6 healthy controls (HC). MFAP4 levels were measured in 152 patients (49 MS, 62 NMOSD, 22 myelin oligodendrocyte glycoprotein associated disease (MOGAD), and 19 isolated optic neuritis (ION). Results : MFAP4 localized to the meninges and the vascular/perivascular spaces, particularly intense in the optic nerve. At sites of active inflammation, MFAP4 reactivity was reduced in NMOSD and acute MS and to a lesser degree in progressive MS. CSF MFAP4 levels were reduced in patients during acute attacks compared to HC. There was a positive correlation between number of relapses and CSF MFAP4 levels (rho=0.33, p =0.004). CSF MFAP4 levels were lower in 53 samples obtained at presenting attack (mean U/mL: 14.3, MOGAD 9.7 and ION 14.6 relative to HC 17.9. ( p =0.013, p =0.000 and p =0.019 respectively). All patients with acute ON relapse (n=68) had reduced CSF MFAP4 relative to HC (mean U/mL: 14.5 vs. 17.9, p =0.006). CSF MFAP4 levels correlated negatively with relapse severity (rho=-0.41, p =0.017). Discussion.: MFAP4 immunoreactivity was observed in CNS and reduced at sites of active inflammation. CSF levels of MFAP4 were reduced following acute relaps e and may serve as a marker of disease activity and attack severity.
