The contribution of tumor necrosis factor to multiple sclerosis: a possible role in progression independent of relapse?

Tumor necrosis factor (TNF) is a pleiotropic cytokine regulating many physiological and pathological immune-mediated processes. Specifically, it has been recognized as an essential pro-inflammatory cytokine implicated in multiple sclerosis (MS) pathogenesis and progression. MS is a chronic immune-mediated disease of the central nervous system, characterized by multifocal acute and chronic inflammatory demyelination in white and grey matter, along with neuroaxonal loss. A recent concept in the field of MS research is disability resulting from Progression Independent of Relapse Activity (PIRA). PIRA recognizes that disability accumulation since the early phase of the disease can occur independently of relapse activity overcoming the traditional dualistic view of MS as either a relapsing-inflammatory or a progressive-neurodegenerative disease. Several studies have demonstrated an upregulation in TNF expression in both acute and chronic active MS brain lesions. Additionally, elevated TNF levels have been observed in the serum and cerebrospinal fluid of MS patients. TNF appears to play a significant role in maintaining chronic intrathecal inflammation, promoting axonal damage neurodegeneration, and consequently contributing to disease progression and disability accumulation. In summary, this review highlights the current understanding of TNF and its receptors in MS progression, specifically focusing on the relatively unexplored PIRA condition. Further research in this area holds promise for potential therapeutic interventions targeting TNF to mitigate disability in MS patients.

Acute Inflammatory Diseases of the Central Nervous System After SARS-CoV-2 Vaccination.

BACKGROUND AND OBJECTIVES: Acute inflammatory CNS diseases include neuromyelitis optica spectrum disorders (NMOSDs) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Both MOGAD and acute disseminated encephalomyelitis (ADEM) have been reported after vaccination. Consequently, the mass SARS-CoV-2 vaccination program could result in increased rates of these conditions. We described the features of patients presenting with new acute CNS demyelination resembling NMOSDs or MOGAD within 8 weeks of SARS-CoV-2 vaccination. METHODS: The study included a prospective case series of patients referred to highly specialized NMOSD services in the UK from the introduction of SARS-CoV-2 vaccination program up to May 2022. Twenty-five patients presented with new optic neuritis (ON) and/or transverse myelitis (TM) ± other CNS inflammation within 8 weeks of vaccination with either AstraZeneca (ChAdOx1S) or Pfizer (BNT162b2) vaccines. Their clinical records and paraclinical investigations including MRI scans were reviewed. Serologic testing for antibodies to myelin oligodendrocyte glycoprotein (MOG) and aquaporin 4 (AQP4) was performed using live cell-based assays. Patients' outcomes were graded good, moderate, or poor based on the last clinical assessment. RESULTS: Of 25 patients identified (median age 38 years, 14 female), 12 (48%) had MOG antibodies (MOGIgG+), 2 (8%) had aquaporin 4 antibodies (AQP4IgG+), and 11 (44%) had neither. Twelve of 14 (86%) antibody-positive patients received the ChAdOx1S vaccine. MOGIgG+ patients presented most commonly with TM (10/12, 83%), frequently in combination with ADEM-like brain/brainstem lesions (6/12, 50%). Transverse myelitis was longitudinally extensive in 7 of the 10 patients. A peak in new MOGAD cases in Spring 2021 was attributable to postvaccine cases. Both AQP4IgG+ patients presented with brain lesions and TM. Four of 6 (67%) seronegative ChAdOx1S recipients experienced longitudinally extensive TM (LETM) compared with 1 of 5 (20%) of the BNT162b2 group, and facial nerve inflammation was reported only in ChAdOx1S recipients (2/5, 40%). Guillain-Barre syndrome was confirmed in 1 seronegative ChAdOx1S recipient and suspected in another. DISCUSSION: ChAdOx1S was associated with 12/14 antibody-positive cases, the majority MOGAD. MOGAD patients presented atypically, only 2 with isolated ON (1 after BNT162b2 vaccine) but with frequent ADEM-like brain lesions and LETM. Within the seronegative group, phenotypic differences were observed between ChAdOx1S and BNT162b2 recipients. These observations might support a causative role of the ChAdOx1S vaccine in inflammatory CNS disease and particularly MOGAD. Further study of this cohort could provide insights into vaccine-associated immunopathology.

Characteristics and treatment of Multiple Sclerosis-related trigeminal neuralgia: An Italian multi-centre study.

BACKGROUND: The prevalence of trigeminal neuralgia (TN) in Multiple Sclerosis (MS) patients is higher than in the general population and its management can be particularly challenging. Our aim is to describe the characteristics, treatment and prognostic factors of MS-related TN in a retrospective multicentre study. METHODS: Neurologists members of the RIREMS group (Rising Researchers in MS) enrolled MS patients with a TN diagnosis and filled out a spreadsheet comprising their clinical data. RESULTS: Population consisted of 298 patients. First-choice preventive treatments were carbamazepine and oxcarbazepine. A surgical procedure was performed in 81 (30%) patients, most commonly gamma knife stereotactic radiosurgery (37%), followed by microvascular decompression (22%) and radiofrequency thermocoagulation (21%); one third of patients underwent at least two procedures. Surgery was associated with higher disability, male sex and longer interval between MS and TN onset. Patients (77%) who stayed on at least one preventive medication at most recent follow-up, after a mean period of 8 years, had a higher disability compared to the untreated group. Furthermore, patients with higher disability at TN onset were less likely to discontinue their first preventive medication due to pain remission, had bilateral TN more frequently and underwent surgical interventions earlier. CONCLUSION: MS patients with a higher disability at TN onset and with a longer interval between MS and TN onset had differing clinical features and outcomes: pain was more frequently bilateral, surgery was more frequent and anticipated, and preventive medication discontinuation due to pain remission was less common.