INTRODUCTION: Multiple Sclerosis (MS), a debilitating central nervous system (CNS) disorder, is characterized by inflammation, demyelination, and neuronal degeneration. Despite advancements in immunomodulatory treatments, neuroprotective or restorative strategies remain inadequate. Our research is focusing on the potential of the positive allosteric modulator of AMPA receptors (AMPA-PAM), PF4778574, in addressing MS symptoms. METHODS: We utilized the MOG35-55 induced experimental autoimmune encephalomyelitis (EAE) model in C57BL6J mice to examine PF4778574's therapeutic and prophylactic efficacy. Our comprehensive approach included clinical scoring, optical coherence tomography (OCT), optomotor response (OMR) and histological assessments. Additionally, we explored the effects of PF4778574 in comparison and in combination with the immunomodulatory agent fingolimod, and investigated the impact on Cuprizone induced toxic demyelination. RESULTS: Prophylactic administration of PF4778574 showed notable improvement in clinical EAE indices and reduction in neuronal loss. While it did not diminish microglial activity, it reduced demyelinated areas in optic nerves and in the corpus callosum. Both PF4778574 and fingolimod significantly enhanced clinical EAE scores and decreased demyelination. However, their combination did not yield additional benefits. In the cuprizone model, PF4778574 increased oligodendrocyte precursor and mature myelin-forming cells, suggesting a pro-remyelinating effect. DISCUSSION: PF4778574 demonstrates promise in mitigating EAE effects, especially in terms of clinical disability and demyelination. These results suggest AMPA-PAMs as potential targets of interest for MS treatment beyond immunomodulatory approaches.

• Keywords
• AMPA, AMPA-PAM, EAE, excitotoxicity, multiple sclerosis, neuroprotection, optical coherence tomography,
• MeSH
• Allosteric Regulation drug effects   MeSH
• Receptors, AMPA * metabolism   MeSH
• Encephalomyelitis, Autoimmune, Experimental * drug therapy   metabolism   pathology   immunology   MeSH
• Fingolimod Hydrochloride pharmacology   MeSH
• Cuprizone MeSH
• Disease Models, Animal MeSH
• Mice, Inbred C57BL MeSH
• Mice MeSH
• Multiple Sclerosis * drug therapy   metabolism   pathology   MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Aminopyridines MeSH
• Receptors, AMPA * MeSH
• Fingolimod Hydrochloride MeSH
• Cuprizone MeSH
• pexidartinib MeSH Browser
• Pyrroles MeSH

BACKGROUND AND OBJECTIVES: Retinal optical coherence tomography (OCT) provides promising prognostic imaging biomarkers for future disease activity in multiple sclerosis (MS). However, raw OCT-derived measures have multiple dependencies, supporting the need for establishing reference values adjusted for possible confounders. The purpose of this study was to investigate the capacity for age-adjusted z scores of OCT-derived measures to prognosticate future disease activity and disability worsening in people with MS (PwMS). METHODS: We established age-adjusted OCT reference data using generalized additive models for location, scale, and shape for peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform layer (GCIP) thicknesses, involving 910 and 423 healthy eyes, respectively. Next, we transformed the retinal layer thickness of PwMS from 3 published studies into age-adjusted z scores (pRNFL-z and GCIP-z) based on the reference data. Finally, we investigated the association of pRNFL-z or GCIP-z as predictors with future confirmed disability worsening (Expanded Disability Status Scale score increase) or disease activity (failing of the no evidence of disease activity [NEDA-3] criteria) as outcomes. Cox proportional hazards models or logistic regression analyses were applied according to the original studies. Optimal cutoffs were identified using the Akaike information criterion as well as location with the log-rank and likelihood-ratio tests. RESULTS: In the first cohort (n = 863), 172 PwMS (24%) had disability worsening over a median observational period of 2.0 (interquartile range [IQR]:1.0-3.0) years. Low pRNFL-z (≤-2.04) were associated with an increased risk of disability worsening (adjusted hazard ratio (aHR) [95% CI] = 2.08 [1.47-2.95], p = 3.82e-5). In the second cohort (n = 170), logistic regression analyses revealed that lower pRNFL-z showed a higher likelihood for disability accumulation at the two-year follow-up (reciprocal odds ratio [95% CI] = 1.51[1.06-2.15], p = 0.03). In the third cohort (n = 78), 46 PwMS (59%) did not maintain the NEDA-3 status over a median follow-up of 2.0 (IQR: 1.9-2.1) years. PwMS with low GCIP-z (≤-1.03) had a higher risk of showing disease activity (aHR [95% CI] = 2.14 [1.03-4.43], p = 0.04). Compared with raw values with arbitrary cutoffs, applying the z score approach with optimal cutoffs showed better performance in discrimination and calibration (higher Harrell's concordance index and lower integrated Brier score). DISCUSSION: In conclusion, our work demonstrated reference cohort-based z scores that account for age, a major driver for disease progression in MS, to be a promising approach for creating OCT-derived measures useable across devices and toward individualized prognostication.

• MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Tomography, Optical Coherence * MeSH
• Prognosis MeSH
• Disease Progression * MeSH
• Retina diagnostic imaging   pathology   physiopathology   MeSH
• Multiple Sclerosis * physiopathology   diagnostic imaging   MeSH
• Severity of Illness Index MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Retinal optical coherence tomography has been identified as biomarker for disease progression in relapsing-remitting multiple sclerosis (RRMS), while the dynamics of retinal atrophy in progressive MS are less clear. We investigated retinal layer thickness changes in RRMS, primary and secondary progressive MS (PPMS, SPMS), and their prognostic value for disease activity. Here, we analyzed 2651 OCT measurements of 195 RRMS, 87 SPMS, 125 PPMS patients, and 98 controls from five German MS centers after quality control. Peripapillary and macular retinal nerve fiber layer (pRNFL, mRNFL) thickness predicted future relapses in all MS and RRMS patients while mRNFL and ganglion cell-inner plexiform layer (GCIPL) thickness predicted future MRI activity in RRMS (mRNFL, GCIPL) and PPMS (GCIPL). mRNFL thickness predicted future disability progression in PPMS. However, thickness change rates were subject to considerable amounts of measurement variability. In conclusion, retinal degeneration, most pronounced of pRNFL and GCIPL, occurs in all subtypes. Using the current state of technology, longitudinal assessments of retinal thickness may not be suitable on a single patient level.

• MeSH
• Multiple Sclerosis, Chronic Progressive * diagnostic imaging   pathology   physiopathology   MeSH
• Retinal Degeneration * diagnostic imaging   pathology   MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Magnetic Resonance Imaging methods   MeSH
• Nerve Fibers pathology   MeSH
• Tomography, Optical Coherence * methods   MeSH
• Prognosis MeSH
• Disease Progression * MeSH
• Multiple Sclerosis, Relapsing-Remitting * diagnostic imaging   pathology   physiopathology   MeSH
• Retina * diagnostic imaging   pathology   MeSH
• Retinal Ganglion Cells pathology   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

BACKGROUND AND OBJECTIVES: Optical coherence tomography angiography (OCTA) is a noninvasive high-resolution imaging technique for assessing the retinal vasculature and is increasingly used in various ophthalmologic, neuro-ophthalmologic, and neurologic diseases. To date, there are no validated consensus criteria for quality control (QC) of OCTA. Our study aimed to develop criteria for OCTA quality assessment. METHODS: To establish criteria through (1) extensive literature review on OCTA artifacts and image quality to generate standardized and easy-to-apply OCTA QC criteria, (2) application of OCTA QC criteria to evaluate interrater agreement, (3) identification of reasons for interrater disagreement, revision of OCTA QC criteria, development of OCTA QC scoring guide and training set, and (4) validation of QC criteria in an international, interdisciplinary multicenter study. RESULTS: We identified 7 major aspects that affect OCTA quality: (O) obvious problems, (S) signal strength, (C) centration, (A) algorithm failure, (R) retinal pathology, (M) motion artifacts, and (P) projection artifacts. Seven independent raters applied the OSCAR-MP criteria to a set of 40 OCTA scans from people with MS, Sjogren syndrome, and uveitis and healthy individuals. The interrater kappa was substantial (κ 0.67). Projection artifacts were the main reason for interrater disagreement. Because artifacts can affect only parts of OCTA images, we agreed that prior definition of a specific region of interest (ROI) is crucial for subsequent OCTA quality assessment. To enhance artifact recognition and interrater agreement on reduced image quality, we designed a scoring guide and OCTA training set. Using these educational tools, 23 raters from 14 different centers reached an almost perfect agreement (κ 0.92) for the rejection of poor-quality OCTA images using the OSCAR-MP criteria. DISCUSSION: We propose a 3-step approach for standardized quality control: (1) To define a specific ROI, (2) to assess the occurrence of OCTA artifacts according to the OSCAR-MP criteria, and (3) to evaluate OCTA quality based on the occurrence of different artifacts within the ROI. OSCAR-MP OCTA QC criteria achieved high interrater agreement in an international multicenter study and is a promising QC protocol for application in the context of future clinical trials and studies.

• MeSH
• Fluorescein Angiography methods   MeSH
• Consensus MeSH
• Humans MeSH
• Tomography, Optical Coherence * MeSH
• Retina diagnostic imaging   MeSH
• Retinal Vessels * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH