Falk Steffen

Dr. Falk Steffen

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Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2019 in Stroke
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Journal Article
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TUTimo Uphaus
Timo Uphaus
SBStefan Bittner
Stefan Bittner
SGSonja Gröschel
Sonja Gröschel
FSFalk Steffen
Falk Steffen
MMMuthuraman Muthuraman
Muthuraman Muthuraman
KGKlaus Gröschel
Klaus Gröschel
Background and Purpose—: Ischemic stroke causes major disability as a consequence of neuronal loss and recurrent ischemic events. Biomarkers predicting tissue damage or stroke recurrence might be useful to guide an individualized stroke therapy. NfL (neurofilament light chain) is a promising biomarker that might be used for this purpose. Methods—: We used individual data of patients with an acute ischemic stroke and clinical long term follow-up. Serum NfL (sNfL) was quantified within 24 hours after admission and after 1 year and compared with other biomarkers (GDF15 [growth differentiation factor 15], S100, NT-proBNP [N-terminal pro-B-type natriuretic peptide], ANP [atrial natriuretic peptide], and FABP [fatty acid–binding protein]). The primary end point was functional outcome after 90 days and cerebrovascular events and death (combined cardiovascular end point) within 36 months of follow-up. Results—: Two hundred eleven patients (mean age, 68.7 years; SD, ±12.6; 41.2% women) with median clinical severity on the National Institutes of Health Stroke Scale (NIHSS) score of 3 (interquartile range, 1–5) and long-term follow-up with a median of 41.8 months (interquartile range, 40.0–44.5) were prospectively included. We observed a significant correlation between sNfL and NIHSS at hospital admission (r=0.234; P <0.001). sNfL levels increased with the grade of age-related white matter changes ( P <0.001) and were able to predict unfavorable clinical outcome (modified Rankin Scale score, ≥2) 90 days after stroke (odds ratio [OR], 1.562; 95% CI, 1.003–2.433; P =0.048) together with NIHSS (OR, 1.303; 95% CI, 1.164–1.458; P <0.001) and age-related white matter change rating (severe; OR, 3.326; 95% CI, 1.186–9.326; P =0.022). Similarly, sNfL was valuable for the prediction of the combined cardiovascular end point (OR, 2.002; 95% CI, 1.213–3.302; P =0.007), besides NIHSS (OR, 1.110; 95% CI, 1.000–1.232; P =0.049), diabetes mellitus (OR, 2.942; 95% CI, 1.306–6.630; P =0.005), and age-related white matter change rating (severe; OR, 4.816; 95% CI, 1.206–19.229; P =0.026) after multivariate regression analysis. Kaplan-Meier analysis revealed significantly more combined cardiovascular end points (18 [14.1%] versus 38 [45.8%], log-rank test P <0.001) during long-term follow-up in patients with elevated sNfL levels. Conclusions—: sNFL is a valuable biomarker for functional independence 90 days after ischemic stroke and predicts cardiovascular long-term outcome. Clinical Trial Registration—: URL: http://www.isrctn.com . Unique identifier: ISRCTN 46104198.

16 December 2019 in Nature Communications
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CLChristina Lückel
Christina Lückel
FPFelix Picard
Felix Picard
HRHartmann Raifer
Hartmann Raifer
LCLucia Campos Carrascosa
Lucia Campos Carrascosa
AGAnna Guralnik
Anna Guralnik
MHMagdalena Huber
Magdalena Huber
IL-17-producing CD8+ (Tc17) cells are enriched in active lesions of patients with multiple sclerosis (MS), suggesting a role in the pathogenesis of autoimmunity. Here we show that amelioration of MS by dimethyl fumarate (DMF), a mechanistically elusive drug, associates with suppression of Tc17 cells. DMF treatment results in reduced frequency of Tc17, contrary to Th17 cells, and in a decreased ratio of the regulators RORC-to-TBX21, along with a shift towards cytotoxic T lymphocyte gene expression signature in CD8+ T cells from MS patients. Mechanistically, DMF potentiates the PI3K-AKT-FOXO1-T-BET pathway, thereby limiting IL-17 and RORγt expression as well as STAT5-signaling in a glutathione-dependent manner. This results in chromatin remodeling at the Il17 locus. Consequently, T-BET-deficiency in mice or inhibition of PI3K-AKT, STAT5 or reactive oxygen species prevents DMF-mediated Tc17 suppression. Overall, our data disclose a DMF-AKT-T-BET driven immune modulation and suggest putative therapy targets in MS and beyond.

2 November 2020 in Epilepsia
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OOOumarou Ouédraogo
Oumarou Ouédraogo
RRRose‐Marie Rébillard
Rose‐Marie Rébillard
HJHélène Jamann
Hélène Jamann
VMVictoria Hannah Mamane
Victoria Hannah Mamane
MCMarie‐Laure Clénet
Marie‐Laure Clénet
CLCatherine Larochelle
Catherine Larochelle

27 March 2024 in Science Translational Medicine
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Journal Article
Closed access
CGCatharina C. Gross
Catharina C. Gross
ASAndreas Schulte-Mecklenbeck
Andreas Schulte-Mecklenbeck
OSOlga V. Steinberg
Olga V. Steinberg
TWTimo Wirth
Timo Wirth
SLSarah Lauks
Sarah Lauks
MWMartin S. Weber
Martin S. Weber
One of the biggest challenges in managing multiple sclerosis is the heterogeneity of clinical manifestations and progression trajectories. It still remains to be elucidated whether this heterogeneity is reflected by discrete immune signatures in the blood as a surrogate of disease pathophysiology. Accordingly, individualized treatment selection based on immunobiological principles is still not feasible. Using two independent multicentric longitudinal cohorts of patients with early multiple sclerosis ( n = 309 discovery and n = 232 validation), we were able to identify three distinct peripheral blood immunological endophenotypes by a combination of high-dimensional flow cytometry and serum proteomics, followed by unsupervised clustering. Longitudinal clinical and paraclinical follow-up data collected for the cohorts revealed that these endophenotypes were associated with disease trajectories of inflammation versus early structural damage. Investigating the capacity of immunotherapies to normalize endophenotype-specific immune signatures revealed discrete effect sizes as illustrated by the limited effect of interferon-β on endophenotype 3–related immune signatures. Accordingly, patients who fell into endophenotype 3 subsequently treated with interferon-β exhibited higher disease progression and MRI activity over a 4-year follow-up compared with treatment with other therapies. We therefore propose that ascertaining a patient’s blood immune signature before immunomodulatory treatment initiation may facilitate prediction of clinical disease trajectories and enable personalized treatment decisions based on pathobiological principles.

11 November 2021 in Neurology Neuroimmunology & Neuroinflammation
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MBMarkus Bock
Markus Bock
FSFalk Steffen
Falk Steffen
FZFrauke Zipp
Frauke Zipp
SBStefan Bittner
Stefan Bittner
Background and Objectives Adapted ketogenic diet (AKD) and caloric restriction (CR) have been suggested as alternative therapeutic strategies for multiple sclerosis (MS), but information on their impact on neuroaxonal damage is lacking. Thus, we explored the impact of diets on serum neurofilament light chain (sNfL) levels in patients with relapsing-remitting MS. Methods We retrospectively evaluated a prospective randomized controlled trial of 60 patients with MS who were on a common diet or ketogenic diet or fasting. We examined sNfL levels of 40 participants at baseline and at the end of the study after 6 months using single molecule array assay. Results sNfL levels were investigated in 9 controls, 14 participants on CR, and 17 participants on AKD. Correlation analysis showed an association of sNfL with age and disease duration; an association was also found between sNfL and the Multiple Sclerosis Functional Composite. AKD significantly reduced sNfL levels at 6 months compared with the common diet group (p = 0.001). Discussion For clinical or study use, consider that AKD may incline sNfL levels independent of relapse activity up to 3 months after initiation. At 6 months, AKD, which complements current therapies, reduced sNfL levels, therefore suggesting potential neuroprotective effects in MS. A single cycle of seven-day fasting did not affect sNfL. AKD may be an addition to the armamentarium to help clinicians support patients with MS in a personalized manner with tailored diet strategies. Trial Registration Information Clinical trial registration number NCT01538355.

8 July 2022 in Brain Communications
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TBTobias Brummer
Tobias Brummer
Muthuraman MuthuramanMuthuraman Muthuraman
Muthuraman Muthuraman
FSFalk Steffen
Falk Steffen
TUTimo Uphaus
Timo Uphaus
LMLena Minch
Lena Minch
VFVinzenz Fleischer
Vinzenz Fleischer
Disability in multiple sclerosis is generally classified by sensory and motor symptoms, yet cognitive impairment has been identified as a frequent manifestation already in the early disease stages. Imaging- and more recently blood-based biomarkers have become increasingly important for understanding cognitive decline associated with multiple sclerosis. Thus, we sought to determine the prognostic utility of serum neurofilament light chain levels alone and in combination with MRI markers by examining their ability to predict cognitive impairment in early multiple sclerosis. A comprehensive and detailed assessment of 152 early multiple sclerosis patients (Expanded Disability Status Scale: 1.3 ± 1.2, mean age: 33.0 ± 10.0 years) was performed, which included serum neurofilament light chain measurement, MRI markers (i.e. T2-hyperintense lesion volume and grey matter volume) acquisition and completion of a set of cognitive tests (Symbol Digits Modalities Test, Paced Auditory Serial Addition Test, Verbal Learning and Memory Test) and mood questionnaires (Hospital Anxiety and Depression scale, Fatigue Scale for Motor and Cognitive Functions). Support vector regression, a branch of unsupervised machine learning, was applied to test serum neurofilament light chain and combination models of biomarkers for the prediction of neuropsychological test performance. The support vector regression results were validated in a replication cohort of 101 early multiple sclerosis patients (Expanded Disability Status Scale: 1.1 ± 1.2, mean age: 34.4 ± 10.6 years). Higher serum neurofilament light chain levels were associated with worse Symbol Digits Modalities Test scores after adjusting for age, sex Expanded Disability Status Scale, disease duration and disease-modifying therapy (B = −0.561; SE = 0.192; P = 0.004; 95% CI = −0.940 to −0.182). Besides this association, serum neurofilament light chain levels were not linked to any other cognitive or mood measures (all P-values > 0.05). The tripartite combination of serum neurofilament light chain levels, lesion volume and grey matter volume showed a cross-validated accuracy of 88.7% (90.8% in the replication cohort) in predicting Symbol Digits Modalities Test performance in the support vector regression approach, and outperformed each single biomarker (accuracy range: 68.6–75.6% and 68.9–77.8% in the replication cohort), as well as the dual biomarker combinations (accuracy range: 71.8–82.3% and 72.6–85.6% in the replication cohort). Taken together, early neuro-axonal loss reflects worse information processing speed, the key deficit underlying cognitive dysfunction in multiple sclerosis. Our findings demonstrate that combining blood and imaging measures improves the accuracy of predicting cognitive impairment, highlighting the clinical utility of cross-modal biomarkers in multiple sclerosis.