Lucchinetti, Claudia F.

AbstractObjectiveTo describe demographic, clinical, and radiographic features of tumefactive demyelination (TD) and identify factors associated with severe attacks and poor outcomes.MethodsRetrospective review of TD cases seen at Mayo Clinic, 1990–2021.ResultsOf 257 patients with TD, 183/257 (71%) fulfilled the 2017 multiple sclerosis (MS) McDonald criteria at the last follow‐up, 12/257 (5%) had myelin oligodendrocyte glycoprotein antibody‐associated disease (MOGAD), 0 had aquaporin‐4‐IgG seropositive neuromyelitis optic spectrum disorders (AQP4+ NMOSD), and 62/257 (24%) were cryptogenic. Onset before age 18 was present in 18/257 (7%). Female to male ratio was 1.3:1. Cerebrospinal fluid oligoclonal (CSF) bands were present in 95/153 (62%). TD was the first demyelinating attack in 176/257 (69%). At presentation, 59/126 (47%) fulfilled Barkhof criteria for dissemination in space, 59/100 (59%) had apparent diffusion coefficient (ADC) restriction, and 57/126 (45%) had mass effect. Despite aggressive clinical presentation at onset, 181/257 (70%) of patients remained fully ambulatory (Expanded Disability Status Scale [EDSS] ≤4) after a 3.0‐year median follow‐up duration. Severe initial attack‐related disability (EDSS ≥4) was more common in patients with motor symptoms (81/143 vs. 35/106, p < 0.0001), encephalopathy (20/143 vs. 2/106, p < 0.0001) and ADC restriction on initial MRI (42/63 vs. 15/33, p = 0.04). Poor long‐term outcome (EDSS ≥4) was more common in patients with older onset age (41.9 ± 15 vs. 36.8 ± 15.6, p = 0.02) and motor symptoms at onset (49/76 vs. 66/171, p < 0.0001).InterpretationMost TD patients should be considered part of the MS spectrum after excluding MOGAD and NMOSD. Motor symptoms and older age at presentation portend a poor outcome.

Autoimmune movement disorders are increasingly recognized, but isolated tremor is extremely rare. We describe a 70‐year‐old male with rapidly progressive, severe postural and intention tremor and weight loss. His cerebrospinal fluid was inflammatory and harbored a neural tissue‐restricted antibody. The autoantigen was identified by immunoprecipitation and mass spectrometry and confirmed by antigen‐specific assays to be specific for tenascin‐R. He was investigated for cancer and diagnosed with follicular lymphoma that expressed tenascin‐R suggesting a paraneoplastic origin; cancer treatment and immunotherapy led to complete recovery. With this individualized patient approach and antibody discovery, we expand the spectrum of antibodies accompanying autoimmune hyperkinetic movement disorders. ANN NEUROL 2023;94:502–507

Myelin oligodendrocyte glycoprotein (MOG) antibody–associated disease (MOGAD) is an inflammatory demyelinating CNS condition characterized by the presence of MOG autoantibodies. We sought to investigate whether human MOG autoantibodies are capable of mediating damage to MOG-expressing cells through multiple mechanisms. We developed high-throughput assays to measure complement activity (CA), complement-dependent cytotoxicity (CDC), antibody-dependent cellular phagocytosis (ADCP), and antibody-dependent cellular cytotoxicity (ADCC) of live MOG-expressing cells. MOGAD patient sera effectively mediate all of these effector functions. Our collective analyses reveal that (a) cytotoxicity is not incumbent on MOG autoantibody quantity alone; (b) engagement of effector functions by MOGAD patient serum is bimodal, with some sera exhibiting cytotoxic capacity while others did not; (c) the magnitude of CDC and ADCP is elevated closer to relapse, while MOG-IgG binding is not; and (d) all IgG subclasses can damage MOG-expressing cells. Histopathology from a representative MOGAD case revealed congruence between lesion histology and serum CDC and ADCP, and we identified NK cells, mediators of ADCC, in the cerebrospinal fluid of relapsing patients with MOGAD. Thus, MOGAD-derived autoantibodies are cytotoxic to MOG-expressing cells through multiple mechanisms, and assays quantifying CDC and ADCP may prove to be effective tools for predicting risk of future relapses.

AbstractObjectiveIn this observational study on a cohort of biopsy‐proven central nervous system demyelinating disease consistent with MS, we examined the relationship between early‐active demyelinating lesion immunopattern (IP) with subsequent clinical course, radiographic progression, and cognitive function.MethodsSeventy‐five patients had at least one early‐active lesion on biopsy and were pathologically classified into three immunopatterns based on published criteria. The median time from biopsy at follow‐up was 11 years, median age at biopsy ‐ 41, EDSS ‐ 4.0. At last follow‐up, the median age was 50, EDSS ‐ 3.0. Clinical examination, cognitive assessment (CogState battery), and 3‐Tesla‐MRI (MPRAGE/FLAIR/T2/DIR/PSIR/DTI) were obtained.ResultsIP‐I was identified in 14/75 (19%), IP‐II was identified in 41/75 (56%), and IP‐III was identified in 18/75 (25%) patients. Patients did not differ significantly by immunopattern in clinical measures at onset or last follow‐up. The proportions of disease courses after a median of 11 years were similar across immunopatterns, relapsing–remitting being most common (63%), followed by monophasic (32%). No differences in volumetric or DTI measures were found. CogState performance was similar for most tasks. A slight yet statistically significant difference was identified for episodic memory scores, with IP‐III patients recalling one word less on average.InterpretationIn this study, immunopathological heterogeneity of early‐active MS lesions identified at biopsy does not correlate with different long‐term clinical, neuroimaging or cognitive outcomes. This could be explained by the fact that while active white matter lesions are pathological substrates for relapses, MS progression is driven by mechanisms converging across immunopatterns, regardless of pathogenic mechanisms driving the acute demyelinated plaque.