Faculty Bibliography

Paired vagus nerve stimulation (VNS) has emerged as a promising strategy to potentiate recovery after neurological injury. This approach, which combines short bursts of electrical stimulation of the vagus nerve with rehabilitation exercises, received approval from the US Food and Drug Aministration in 2021 as the first neuromodulation-based therapy for chronic stroke. Because this treatment is increasingly implemented in clinical practice, there is a need to take stock of what we know about this approach and what we have yet to learn. Here, we provide a survey on the foundational basis of VNS therapy for stroke and offer insight into the mechanisms that underlie potentiated recovery, focusing on the principles of neuromodulatory reinforcement. We discuss the current state of observations regarding synaptic reorganization in motor networks that are enhanced by VNS, and we propose other prospective loci of neuromodulation that should be evaluated in the future. Finally, we highlight the future opportunities and challenges to be faced as this approach is increasingly translated to clinical use. Collectively, a clearer understanding of the mechanistic basis of VNS therapy may reveal ways to maximize its benefits.

BACKGROUND/UNASSIGNED:In the DISCOMS (DISCOntinuation of disease-modifying therapies (DMTs) in multiple sclerosis (MS)) randomized clinical trial, we could not demonstrate that discontinuing MS DMTs in older, stable adults was not inferior to continuing DMTs. Relapses were rare in both groups, and most new disease activity was one to two new brain magnetic resonance imaging (MRI) lesions unassociated with clinical changes. OBJECTIVE/AIMS/UNASSIGNED:Describe results of the DISCOMS extension study. METHODS/UNASSIGNED:Among 10/19 of the original sites, we enrolled patients who completed DISCOMS; did not reach the primary endpoint during the original trial; and retained original randomized assignment. Participants completed one study visit and brain MRI at least 30 months after original enrollment in DISCOMS. Primary endpoint was time from entry into the primary study to relapse or new brain MRI activity. RESULTS/UNASSIGNED:= 0.043 from log-rank test). CONCLUSIONS/UNASSIGNED:From entry into DISCOMS extension study, time to new MS activity remained shorter in discontinuers, but relapses were absent and new brain MRI lesions were rare.

OBJECTIVE:To examine the efficacy and safety of sodium oxybate versus placebo in a phase IIb randomized double-blind placebo-controlled 2-period cross-over clinical trial in patients with isolated laryngeal dystonia (LD). METHODS:The study was conducted from January 2018 to December 2021, pausing during the COVID-19 pandemic, at Massachusetts Eye and Ear in 106 patients with alcohol-responsive (EtOH+) and alcohol-non-responsive (EtOH-) LD (53 to receive 1.5g of sodium oxybate first, 53 to receive matching placebo first). The primary outcome was a change from baseline in LD symptom severity 40 minutes after drug intake. Safety was based on vital signs, cognitive function, suicidality, daytime sleepiness, and adverse events. Patients, investigators, and outcome assessors were masked to study procedures. RESULTS:Compared to baseline, EtOH+ but not EtOH- patients had a statistically significant improvement in LD symptoms following sodium oxybate versus placebo (EtOH+: 98.75% confidence interval [CI] = 0.6-26.9; p = 0.008; EtOH-: 98.75% CI = -6.2 to 18.7; p = 0.42). Statistically significant minimum drug efficacy in EtOH+ patients was found at ≥16% symptom improvement (OR = 2.09; 98.75% CI = 0.75-5.80; p = 0.036), with an average of 40.81% benefits (98.75% CI = 34.7-48.6). Drug efficacy waned by 300 minutes after intake without a rebound. No changes were found in cognitive function, suicidality, or vital signs. Common adverse events included mild dizziness, nausea, and daytime sleepiness. INTERPRETATION/CONCLUSIONS:Sodium oxybate showed clinically meaningful improvement of symptoms in EtOH+ LD patients, with acceptable tolerability. Sodium oxybate offers the first pathophysiologically relevant oral treatment for laryngeal dystonia. ANN NEUROL 2024.

BACKGROUND:Spetzler-Martin (SM) Grade III brain arteriovenous malformations (BAVMs) represent a transitional risk zone between low- and high-grade BAVMs, characterized by diverse angioarchitecture. The primary treatment options are endovascular embolization, microsurgical resection (MS), and stereotactic radiosurgery (SRS). This study compares the efficacy and outcomes of MS and SRS. METHODS:We conducted a multicenter, retrospective study involving patients from the MISTA database with SM Grade III BAVMs treated with MS or SRS between 2010 and 2023. Propensity matching was based on age, favorable modified Rankin Score (mRS) at presentation, nidus size, rupture status, location depth, and eloquence. RESULTS:, p = 0.6) were similar. MS showed higher obliteration rates (93.3 %) compared to SRS (46.7 %) at the last follow-up (p < 0.001). The median time to obliteration post-SRS was 31.5 months (IQR: 15.3-60.0). SRS obliteration rates were 19 %, 29 %, and 59 % at 24, 36, and 60 months, respectively. Overall complication rates (MS: 30 % vs. SRS: 20 %, p = 0.4) and permanent complications (MS: 10 % vs. SRS: 13.3 %, p > 0.9) were similar. Hemorrhage occurred once in the MS group and none in the SRS (p > 0.9). Favorable outcomes (mRS 0-2) were higher with SRS than MS (93.3 % vs 80.0 %, p = 0.3), with one AVM-related mortality in the MS group. CONCLUSION/CONCLUSIONS:MS and SRS are viable treatments for SM Grade III BAVMs. Treatment choice should be individualized by a multidisciplinary team, considering patient goals.

The α-synuclein seed amplification assay (αSyn-SAA) sensitively detects Lewy pathology, the amyloid state of α-synuclein, in the cerebrospinal fluid (CSF) of patients with Parkinson's disease (PD). The αSyn-SAA harnesses the physics of seeding, whereby a superconcentrated solution of recombinant α-synuclein lowers the thermodynamic threshold (nucleation barrier) for aggregated α-synuclein to act as a nucleation catalyst ("seed") to trigger the precipitation (nucleation) of monomeric α-synuclein into pathology. This laboratory setup increases the signal for identifying a catalyst if one is present in the tissue examined. The result is binary: positive, meaning precipitation occurred, and a catalyst is present, or negative, meaning no precipitation, therefore no catalyst. Since protein precipitation via seeding can only occur at a concentration many-fold higher than the human brain, laboratory-elicited seeding does not mean human brain seeding. We suggest that a positive αSyn-SAA reveals the presence of pathological α-synuclein but not the underlying etiology for the precipitation of monomeric α-synuclein into its pathological form. Thus, a positive αSyn-SAA supports a clinical diagnosis of PD but cannot inform disease pathogenesis, ascertain severity, predict the rate of progression, define biology or biological subtypes, or monitor treatment response.

Cerebral accumulation of alpha-synuclein (αSyn) aggregates is the hallmark event in a group of neurodegenerative diseases-collectively called synucleinopathies-which include Parkinson's disease, dementia with Lewy bodies and multiple system atrophy. Currently, these are diagnosed by their clinical symptoms and definitively confirmed postmortem by the presence of αSyn deposits in the brain. Here, we summarize the drawbacks of the current clinical definition of synucleinopathies and outline the rationale for moving toward an earlier, biology-anchored definition of these disorders, with or without the presence of clinical symptoms. We underscore the utility of the αSyn seed amplification assay to detect aggregated αSyn in living patients and to differentiate between neuronal or glial αSyn pathology. We anticipate that a biological definition of synucleinopathies, if well-integrated with the current clinical classifications, will enable further understanding of the disease pathogenesis and contribute to the development of effective, disease-modifying therapies.

T cell receptor (TCR) gene therapy is a potent form of cellular immunotherapy in which patient T cells are genetically engineered to express TCRs with defined tumor reactivity. However, the isolation of therapeutic TCRs is complicated by both the general scarcity of tumor-specific T cells among patient T cell repertoires and the patient-specific nature of T cell epitopes expressed on tumors. Here we describe a high-throughput, personalized TCR discovery pipeline that enables the assembly of complex synthetic TCR libraries in a one-pot reaction, followed by pooled expression in reporter T cells and functional genetic screening against patient-derived tumor or antigen-presenting cells. We applied the method to screen thousands of tumor-infiltrating lymphocyte (TIL)-derived TCRs from multiple patients and identified dozens of CD4⁺ and CD8⁺ T-cell-derived TCRs with potent tumor reactivity, including TCRs that recognized patient-specific neoantigens.

BACKGROUND:The goal of precision oncology is to find effective therapeutics for every patient. Through the inclusion of emerging therapeutics in a high-throughput drug screening platform, our functional genomics pipeline inverts the common paradigm to identify patient populations that are likely to benefit from novel therapeutic strategies. APPROACH/METHODS:Utilizing drug screening data across a panel of 46 cancer cell lines from 11 tumor lineages, we identified an ovarian cancer-specific sensitivity to the first-in-class CRL4 inhibitors KH-4-43 and 33-11. CRL4 (i.e., Cullin-4 RING E3 ubiquitin ligase) is known to be dysregulated in a variety of cancer contexts, making it an attractive therapeutic target. Unlike proteasome inhibitors that are associated with broad toxicity, CRL4 inhibition offers the potential for tumor-specific effects. RESULTS:We observed that CRL4 inhibition negatively regulates core gene signatures that are upregulated in ovarian tumors and significantly slowed tumor growth as compared to the standard of care, cisplatin, in OVCAR8 xenografts. Building on this, we performed combination drug screening in conjunction with proteomic and transcriptomic profiling to identify ways to improve the antitumor effects of CRL4 inhibition in ovarian cancer models. CRL4 inhibition consistently resulted in activation of the mitogen-activated protein kinase (MAPK) signaling cascade at both the transcriptomic and protein levels, suggesting that survival signaling is induced in response to CRL4 inhibition. These observations were concordant with the results of the combination drug screens in seven ovarian cancer cell lines that showed CRL4 inhibition cooperates with MEK inhibition. Preclinical studies in OVCAR8 and A2780 xenografts confirmed the therapeutic potential of the combination of KH-4-43 and trametinib, which extended overall survival and slowed tumor progression relative to either single agent or the standard of care. CONCLUSIONS:Together, these data demonstrate the prospective utility of functional modeling pipelines for therapeutic development and underscore the clinical potential of CRL4 inhibition in the ovarian cancer context. HIGHLIGHTS/CONCLUSIONS:A precision medicine pipeline identifies ovarian cancer sensitivity to CRL4 inhibitors. CRL4 inhibition induces activation of MAPK signalling as identified by RNA sequencing, proteomics, and phosphoproteomics. Inhibitor combinations that target both CRL4 and this CRL4 inhibitor-induced survival signalling enhance ovarian cancer sensitivity to treatment.