Response Marker for Interferon-beta Treatment in Multiple Sclerosis

Hintergrund: Interferon-β (IFNβ) war die erste zugelassene Substanz für die Behandlung der schubförmig-remittierenden Multiplen Sklerose (RR-MS). Die therapeutisch relevanten Wirkmechanismen dieses hochgradig pleiotropen Zytokins sind trotz intensiver Forschung noch nicht genau definiert. Ziel der vorliegenden Arbeit war es, die Genexpression bestimmter Kandidatengene mit dem klinischen Therapieerfolg zu korrelieren. Methoden: Aufbauend auf Literatur-Recherchen wurde eine Auswahl mehrerer Gene (TRAIL, CD95, CD95L, Bcl-2, Bag-1, Bcl-XL, FLIP, Caspase-3) getroffen. Deren Genexpression wurde dann mittels Real-time PCR in einer longitudinalen Untersuchung in PBMC von RR-MS Patienten, die an einer therapeutischen Studie mit IFNβ 1a teilnahmen, bestimmt. Aufgrund klinischer Parameter wurden die Patienten in sog. Responder und Nonresponder eingeteilt, um den klinischen Therapieerfolg mit der Genexpression der ausgewählten Kandidatengene zu korrelieren. Relevante Ergebnisse wurden an einer zweiten unabhängigen Patientenkohorte überprüft. Ergebnisse: Therapieresponder unterschieden sich von Nonrespondern durch eine frühe und anhaltende Hochregulation von TRAIL (MANOVA p< 0,0001). Auch auf Proteinebene zeichneten sich die Therapieresponder durch signifikant höhere Werte für sTRAIL gegenüber den Nonrespondern aus (MANOVA p<0,001). Bei einem Cut-off von 584,1 pg/ml konnte der Therapieerfolg anhand der sTRAIL Werte vor Therapie mit einer Spezifität von 90,5% und einer Sensitivität von 71,4% vorhergesagt werden. Eine Korrelation des therapeutischen Ansprechens mit der Transkriptionsrate der weiteren untersuchten apoptoserelevanten Gene konnte nicht nachgewiesen werden. Interpretation: Mit TRAIL konnte ein Kandidatengen gefunden werden, dessen Expressionsniveau mit dem klinischen Behandlungserfolg korreliert. Mit TRAIL gelang außerdem die Identifizierung des ersten prognostischen Markers einer IFN-β Therapie bei MS.Background: A substantial number of multiple sclerosis (MS) patients fail to respond to interferon- (IFN-), widely used as immunomodulatory therapy in this disease. Here, the functional relevance of TNF-related apoptosis inducing ligand (TRAIL), recently shown to be upregulated upon incubation with IFN-, for clinical treatment response, was examined. Methods: Gene expression was quantified longitudinally by realtime-PCR in peripheral immune cells of 82 MS patients. In a first cohort of 62 patients, 20 were classified as ´first year responders´ due to the lack of relapses during IFN-a therapy and 19 as ´first year non-responders´. A second cohort, also characterized by MRI, consisted of 11 patients on IFN- 1a and 9 non-treated patients. Soluble TRAIL protein levels were determined by ELISA in serum samples of 49 patients prior to therapy (29 responders, 20 non-responders), as well as longitudinally during therapy. Findings: In both patient cohorts, drug-responders could be discriminated from non-responders by early and sustained TRAIL gene induction (MANOVA, p<0.0001, each). Elevated levels of soluble TRAIL protein in patients´ sera prior to the start of therapy allowed prediction of the treatment response in the first year (ROC analysis with area under the curve 0.879 [0.785-0.974])

Proresolution lipid mediators in multiple sclerosis - differential, disease severity-dependent synthesis - a clinical pilot trial.

The severity and longevity of inflammation is controlled by endogenous counter-regulatory signals. Among them are long-chain polyunsaturated fatty acid (PUFA)-derived lipid mediators, which promote the resolution of inflammation, an active process for returning to tissue homeostasis.To determine whether endogenous production of lipid-derived resolution agonists is regulated differentially in patients with highly active and less active multiple sclerosis (MS).Matched-pairs study in University hospital Neurology department.Based on clinical (relapse frequency) and paraclinical (MRI lesions, contrast enhancement) criteria, 10 pairs of age- and sex-matched patients with relapsing-remitting MS were assigned either to a group with highly active or less active MS. Lipid mediators were quantified in serum and cerebrospinal fluid using LC-MS/MS-based lipidomics.Levels of the key arachidonic (ω-6) and docosahexaenoic acid (ω-6)-derived mediators prostaglandins (PG), leukotrienes, hydroxyeicosatetraenoic acids (HETE) and resolution agonists lipoxin A(4) (LXA(4)), resolvin D1 (RvD1) and neuroprotectin D1 (NPD1) were quantified. In the patient group with highly active MS, 15-HETE and PGE(2) were increased, which are products of the 15-lipoxygenase and cyclooxygenase pathways. The proresolution mediator RvD1 was significantly upregulated and NPD1 was detected in the highly active group only. LXA(4) levels were not increased in patients with highly active MS.Lipid mediator pathways are regulated differentially in the cerebrospinal fluid of MS patients, depending on disease severity. Non-exhaustive or possibly 'delayed' resolution pathways may suggest a defective resolution program in patients with highly active MS. Longitudinal analyses are required to hetero-typify this differential resolution capacity, which may be associated with disease progression, longevity and eventual termination

LC/MS/MS Lipid Mediator Profiling.

<p>A) MRM profile of 12 eicosanoid and docosanoid synthetic standards (NPD1, 4-HDHA, 17-HDHA, RVD1, PGE₂, PGD₂, LTB₄, 6-trans LTB₄ (C1), 6-trans-12-epi-LTB₄ (C2), 12-HETE, 15-HETE, 5-HETE). B) Representative MRM chromatogram of 15-HETE, PGE₂ and RvD1 from patients with less active MS (black line) and with highly active MS (red line). MRM signals (CPS) were corrected for recovery and cerebrospinal fluid sample size. Calibration curves (1–1000 pg) and specific LC retention times for each compound were established with synthetic standards (Cayman Chemical, Ann Arbor, MI). Structures were confirmed for selected samples by MS/MS analyses using enhanced product ion mode with appropriate selection of the parent ion in quadrupole 1.</p

Phylogenetic patterns of trait and trait plasticity evolution: Insights from amphibian embryos

Environmental variation favors the evolution of phenotypic plasticity. For many species, we understand the costs and benefits of different phenotypes, but we lack a broad understanding of how plastic traits evolve across large clades. Using identical experiments conducted across North America, we examined prey responses to predator cues. We quantified five life-history traits and the magnitude of their plasticity for 23 amphibian species/populations (spanning three families and five genera) when exposed to no cues, crushed-egg cues, and predatory crayfish cues. Embryonic responses varied considerably among species and phylogenetic signal was common among the traits, whereas phylogenetic signal was rare for trait plasticities. Among trait-evolution models, the Ornstein-Uhlenbeck (OU) model provided the best fit or was essentially tied with Brownian motion. Using the best fitting model, evolutionary rates for plasticities were higher than traits for three life-history traits and lower for two. These data suggest that the evolution of life-history traits in amphibian embryos is more constrained by a species' position in the phylogeny than is the evolution of life history plasticities. The fact that an OU model of trait evolution was often a good fit to patterns of trait variation may indicate adaptive optima for traits and their plasticities