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Background: Limited licensed medications are available for multiple sclerosis (MS) in pediatric patients., Objective: To evaluate the efficacy, safety, and tolerability of alemtuzumab in pediatric patients with relapsing-remitting multiple sclerosis (RRMS) and disease activity on prior disease-modifying therapies (DMTs)., Methods: LemKids was a multicenter, multinational, single-arm, open-label, switch (from ongoing DMT to alemtuzumab treatment) study in pediatric RRMS patients (aged 10-<18 years), with disease activity on DMT. The primary endpoint was a comparison of the number of new/enlarging T2 lesions on the magnetic resonance imaging of the brain between the prior-DMT period and alemtuzumab treatment., Results: This study was prematurely terminated due to low enrollment and an European Medicines Agency Article-20 pharmacovigilance review of alemtuzumab in adult RRMS. Of 46 screened patients, 16 were enrolled; 12 completed prior-DMT treatment period; 11 received alemtuzumab of whom 7 completed treatment. Patients on alemtuzumab developed fewer new/enlarging T2 lesions compared with prior-DMT (7 vs 178, relative risk (95% confidence interval): 0.04 (0.01-0.14)). No significant pharmacodynamic changes or safety concerns were noted in this limited dataset., Conclusion: Alemtuzumab treatment was associated with a low number of new/enlarging T2 lesions in pediatric patients with RRMS and was safe and well tolerated in seven patients during infusion and the initial 4 months., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: T.C. received consulting fees from Genentech-Roche and Novartis; is member of advisory boards of Novartis, Roche-Genentech, and Sanofi; received research support from Novartis, Sanofi, Serono, and Verily; and received speaking fees from Medscape. D.L.A. received personal compensation for serving as a consultant for Alexion, Biogen, Celgene, Eli Lilly, EMD Serono, Frequency Therapeutics, Genentech, Merck, Novartis, Roche, Sanofi, and Shionogi; and holds an equity interest in NeuroRx. P.Q. received consultancy or speaking fees from AbbVie, Amgen, Bristol-Myers Squibb, Chugai-Roche, Eli Lilly, Novartis, Novimmune, Pfizer, and Swedish Orphan Biovitrum; and participated in two data safety monitoring boards for Sanofi. M.C., W.H., and S.J. are employees of Sanofi; may hold shares and/or stock options in the company. E.K.H. received honoraria and grant support from Actelion, Biogen, Merck Serono, Janssen, Novartis, Receptos, Roche, Sanofi, and Teva; and support from the Ministry of Education of Czech Republic project (Cooperation LF1, research area Neuroscience) and the National Institute for Neurological Research (Programme EXCELES, ID Project No. LX22NPO5107—funded by the European Union-Next Generation EU).

Background: Teriflunomide is contraindicated in pregnancy. Some pregnancies have occurred despite guidance to use effective contraception., Objectives: To report outcomes of pregnancies occurring in teriflunomide clinical trials and the post-marketing setting., Methods: Outcomes are summarized for pregnancies in teriflunomide monotherapy clinical trials and the post-marketing setting (data cutoff: December 2017)., Results: Of 437 confirmed teriflunomide-exposed pregnancies, 222 had known outcomes (70 from clinical trials; 152 from the post-marketing setting); 161 were reported prospectively and 61 retrospectively. There were 107 (48.2%) live births, 63 (28.4%) elective abortions, 47 (21.2%) spontaneous abortions, 3 (1.4%) ectopic pregnancies, 1 (0.5%) stillbirth, and 1 (0.5%) maternal death leading to fetal death. Four birth defects were reported among cases with known pregnancy outcome: ureteropyeloectasia (only defect considered major); congenital hydrocephalus; ventricular septal defect; and malformation of right foot valgus. A case of cystic hygroma was identified on antenatal ultrasound (pregnancy outcome unknown). One elective abortion followed prenatal diagnosis of fetal anomaly (blighted ovum). The risk of major birth defects in prospectively reported live birth/stillbirth outcomes was 3.6% (1/28) in clinical trials and 0.0% (0/51) in post-marketing reports., Conclusions: Outcomes were consistent with the general population. Current human data do not indicate a teratogenic signal in teriflunomide-exposed pregnancies.

Mutations in the human gene encoding contactin-associated protein-like 2 (CNTNAP2) have been strongly associated with autism spectrum disorders (ASDs). Cntnap2(-/-) mice recapitulate major features of ASD, including social impairment, reduced vocalizations, and repetitive behavior. In addition, Cntnap2(-/-) mice show reduced cortical neuronal synchrony and develop spontaneous seizures throughout adulthood. As suggested for other forms of ASDs, this phenotype could reflect some form of synaptic dysregulation. However, the impact of lifelong deletion of CNTNAP2 on synaptic function in the brain remains unknown. To address this issue, we have assessed excitatory and inhibitory synaptic transmission in acute hippocampal slices of Cntnap2(-/-) mice. We found that although excitatory transmission was mostly normal, inhibition onto CA1 pyramidal cells was altered in Cntnap2(-/-) mice. Specifically, putative perisomatic, but not dendritic, evoked IPSCs were significantly reduced in these mice. Whereas both inhibitory short-term plasticity and miniature IPSC frequency and amplitude were normal in Cntnap2(-/-) mice, we found an unexpected increase in the frequency of spontaneous, action potential-driven IPSCs. Altered hippocampal inhibition could account for the behavioral phenotype Cntnap2(-/-) mice present later in life. Overall, our findings that Cntnap2 deletion selectively impairs perisomatic hippocampal inhibition while sparing excitation provide additional support for synaptic dysfunction as a common mechanism underlying ASDs., (Copyright © 2015 the authors 0270-6474/15/3514681-07$15.00/0.)

Wallerian degeneration (WD) comprises a series of events that includes activation of non-neuronal cells and recruitment of immune cells, creating an inflammatory milieu that leads to extensive nerve fragmentation and subsequent clearance of the myelin debris, both of which are necessary prerequisites for effective nerve regeneration. Previously, we documented accelerated axon regeneration in animals lacking galectin-3 (Gal-3), a molecule associated with myelin clearance. To clarify the mechanisms underlying this enhanced regeneration, we focus here on the early steps of WD following sciatic nerve crush in Gal-3(-/-) mice. Using an in vivo model of nerve degeneration, we observed that removal of myelin debris is more efficient in Gal-3(-/-) than in wild-type (WT) mice; we next used an in vitro phagocytosis assay to document that the phagocytic potential of macrophages and Schwann cells was enhanced in the Gal-3(-/-) mice. Moreover, both RNA and protein levels for the pro-inflammatory cytokines IL-1β and TNF-α, as well as for Toll-like receptor (TLR)-2 and -4, show robust increases in injured nerves from Gal-3(-/-) mice compared to those from WT mice. Collectively, these data indicate that the lack of Gal-3 results in an augmented inflammatory profile that involves the TLR-cytokine pathway, and increases the phagocytic capacity of Schwann cells and macrophages, which ultimately contributes to speeding the course of WD., (© 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Background: There is an unmet need for disease-modifying therapies to improve ambulatory function in disabled subjects with multiple sclerosis., Objectives: Assess the effects of natalizumab on ambulatory function in disabled subjects with relapsing-remitting multiple sclerosis (RRMS) or secondary progressive multiple sclerosis (SPMS)., Methods: We retrospectively reviewed ambulatory function as measured by timed 25-foot walk (T25FW) in clinical trial subjects with an Expanded Disability Status Scale score ≥3.5, including RRMS subjects from the phase 3 AFFIRM and SENTINEL trials, relapsing SPMS subjects from the phase 2 MS231 study, and nonrelapsing SPMS subjects from the phase 1b DELIVER study. For comparison, SPMS subjects from the intramuscular interferon beta-1a (IM IFNβ-1a) IMPACT study were also analyzed. Improvement in ambulation was measured using T25FW responder status; response was defined as faster walking times over shorter (6-9-month) or longer (24-30-month) treatment periods relative to subjects' best predose walking times., Results: There were two to four times more T25FW responders among disabled MS subjects in the natalizumab arms than in the placebo or IM IFNβ-1a arms. Responders walked 25 feet an average of 24%-45% faster than nonresponders., Conclusion: Natalizumab improves ambulatory function in disabled RRMS subjects and may have efficacy in disabled SPMS subjects. Confirmation of the latter finding in a prospective SPMS study is warranted.

Little is known about neuropsychological status changes in multiple sclerosis (MS) patients experiencing a relapse. The Symbol Digit Modalities Test (SDMT) and MS Neuropsychological Screening Questionnaire (MSNQ) are brief measures of cognitive performance and self-reported status, respectively. We retrospectively identified relapses in subjects participating in the 48-week open-label, safety-extension study of natalizumab (STRATA) to determine if changes in cognitive ability occurred during acute relapses. SDMT and MSNQ were administered prior to infusions. We analyzed SDMT and MSNQ scores pre- and post-relapse in 53 MS patients with relapses (cases) and 115 MS patients without relapses (controls) matched on age, gender, baseline SDMT and time from study initiation. ANOVA and GLM were used to compare cases versus controls overall, and stratified by EDSS cerebral functional status (cFS) scores. SDMT change pre- to post-relapse in cases was significantly lower than difference between similar time points in controls (p = 0.003). When comparing visit 2 (two visits pre-relapse) to visit 1 (first visit post-relapse), MSNQ change was significantly different between cases and controls (p = 0.012). For cFS ≤ 1, the change in SDMT was significantly different between cases and controls but not for cFS ≥ 2. These results confirm the involvement of cognitive function during some MS relapses suggesting the SDMT or MSNQ can be used to identify transitory neuropsychological status changes and cognitive relapses.

Background and Objectives: Brief cognitive tests to monitor cognitive impairment in patients with multiple sclerosis (MS) are needed., Methods: Performance on monthly administrations of the Symbol Digit Modalities Test (SDMT) and the MS Neuropsychological Questionnaire (MSNQ) was assessed in 660 patients with MS in 21 countries (109 sites) for 48 weeks in an open-label, safety-extension study of natalizumab., Results: At baseline, the cohort's mean age was 40.1 years, 67.6% were female and the median Expanded Disability Status Scale score was 2.5. Test-retest correlations were high for both SDMT (range 0.89 for weeks 0-4 to 0.96 for weeks 44-48) and MSNQ (0.82 for weeks 0-4 to 0.93 for weeks 44-48). There were no statistically significant effects of geographic region. While SDMT scores improved by 15 points over 48 weeks (p < 0.0001), incremental monthly changes were small (effect size d < 0.3). Similar results were obtained on the MSNQ except that scores moved downward, suggesting fewer cognitive complaints over 48 weeks (p < 0.0001), but again the incremental monthly changes were small (d <-0.2)., Conclusions: These results replicate earlier work in a smaller cohort treated with conventional disease-modifying therapy, and support the reliability of the SDMT and MSNQ as potential screening for monitoring tools for cognition over time.

Background: Accelerating the clearance of therapeutic monoclonal antibodies (mAbs) from the body may be useful to address uncommon but serious complications from treatment, such as progressive multifocal leukoencephalopathy (PML). Treatment of PML requires immune reconstitution. Plasma exchange (PLEX) may accelerate mAb clearance, restoring the function of inhibited proteins and increasing the number or function of leukocytes entering the CNS. We evaluated the efficacy of PLEX in accelerating natalizumab (a therapy for multiple sclerosis [MS] and Crohn disease) clearance and alpha4-integrin desaturation. Restoration of leukocyte transmigratory capacity was evaluated using an in vitro blood-brain barrier (ivBBB)., Methods: Twelve patients with MS receiving natalizumab underwent three 1.5-volume PLEX sessions over 5 or 8 days. Natalizumab concentrations and alpha4-integrin saturation were assessed daily throughout PLEX and three times over the subsequent 2 weeks, comparing results with the same patients the previous month. Peripheral blood mononuclear cell (PBMC) migration (induced by the chemokine CCL2) across an ivBBB was assessed in a subset of six patients with and without PLEX., Results: Serum natalizumab concentrations were reduced by a mean of 92% from baseline to 1 week after three PLEX sessions (p < 0.001). Although average alpha4-integrin saturation was not reduced after PLEX, it was reduced to less than 50% when natalizumab concentrations were below 1 mug/mL. PBMC transmigratory capacity increased 2.2-fold after PLEX (p < 0.006)., Conclusions: Plasma exchange (PLEX) accelerated clearance of natalizumab, and at natalizumab concentrations below 1 mug/mL, desaturation of alpha4-integrin was observed. Also, CCL2-induced leukocyte transmigration across an in vitro blood-brain barrier was increased after PLEX. Therefore, PLEX may be effective in restoring immune effector function in natalizumab-treated patients.

We silenced p53 gene expression in ARPE-19, a human retinal pigmented epithelial cell line using RNA interference. The effect of silencing the p53 gene in proliferating ARPE-19 cells was studied. Four short hairpin RNAs (shRNAs) targeting different regions of human p53 mRNA were delivered individually into ARPE-19 cells using lentiviral vector to produce stable cell lines. p53 mRNA and protein levels were reduced to varying extents in the four shRNA-transduced ARPE-19 cell lines. The cell line that showed greatest reduction (85-90%) of p53 expression showed decreased p21 promoter activation after DNA damage with camptothecin, etoposide and MMS. Whereas treatment of wild type ARPE-19 cells with camptothecin resulted in apoptosis, silencing p53 expression increased their survival. Cell cycle analyses indicated that irradiation resulted in a G(1) arrest in ARPE-19 cells, and that the arrest was significantly reduced in p53-silenced cells. Thus, p53 plays a central role in the response of ARPE-19 cells to DNA damaging agents that act via different mechanisms. Additionally, ARPE-19 cells with reduced p53 expression behave similar to tumor cell lines with mutated or non-functional p53. The present data demonstrate the utility of lentiviral vectors to create stable isogenic cell lines with reduced expression of a specific gene, thereby permitting the study of the function of a gene, the pathways controlled by it, and the effect of therapeutics on a cell with altered genetic makeup in a pair-wise fashion.

Background: Accurate quantification of mRNA in whole blood is made difficult by the simultaneous degradation of gene transcripts and unintended gene induction caused by sample handling or uncontrolled activation of coagulation. This study was designed to compare a new blood collection tube (PAXgene Blood RNA System) and a companion sample preparation reagent set with a traditional sample collection and preparation method for the purpose of gene expression analysis., Methods: We collected parallel blood samples from healthy donors into the new sample collection tubes and control EDTA tubes and performed serial RNA extractions on samples stored for 5 days at room temperature and for up to 90 days at 4 and 20 degrees C. Samples were analyzed by Northern blot analysis or reverse transcription-PCR (RT-PCR)., Results: Specific mRNA concentrations in blood stored in EDTA tubes at any temperature changed substantially, as determined by high-precision RT-PCR. These changes were eliminated or markedly reduced when whole blood was stored in PAXgene tubes. Loss of specific mRNAs, as measured by RT-PCR, reflected total RNA depletion as well as specific mRNA destruction demonstrated by Northern blot analysis. The salutary effects of PAXgene on mRNA stabilization extended to blood samples from eight unrelated donors., Conclusions: Compared with whole blood collected in EDTA tubes and extracted by an organic method, the PAXgene Blood RNA System reduced RNA degradation and inhibited or eliminated gene induction in phlebotomy whole blood samples. Storage of whole blood samples in PAXgene tubes can be recommended for clinically related blood samples that will be analyzed for total or specific RNA content.

Diseases caused by Mycobacterium tuberculosis, M. leprae and M. avium, cause significant morbidity and mortality worldwide. Effective treatments require that the organisms be speciated and that drug susceptibilities for the causative organisms be characterized. Reporter phage technology has been developed as a rapid and convenient method for identifying mycobacterial species and evaluating drug resistance. In this report we describe the construction of luciferase reporter phages from mycobacteriophage D29 DNA. Shuttle phasmids were first constructed with D29 in order to identify non-essential regions of the D29 genomes and to introduce unique cloning sites within that region. Using this approach, we observed that all of the D29 shuttle phasmids had the cosmid vector localized to one area of the phage genome near one cohesive end. These shuttle phasmids had been constructed with a cosmid that could be readily excised from the D29 genome with different sets of restriction enzymes. Luciferase reporter phages were made by substituting the luciferase cassette for the cosmid vector. Recombinant phages with the luciferase cassette fall into two groups. One group produced light and had the expression cassette oriented with the promoter directing transcription away from the cohesive end. In contrast, the other group had the expression cassette in the opposite orientation and failed to produce light during lytic infection, but did produce light in L5 lysogens which are known to repress D29 promoters. These results suggest that a phage promoter of the D29 phage can occlude the expression of a promoter introduced into this region. D29 luciferase reporter phages are capable of detecting low numbers of L5 lysogens like L5 luciferase phages. However, unlike L5 luciferase phages, D29 luciferase phages can readily infect M. tuberculosis and M. bovis BCG, demonstrating that these phages can be used to evaluate drug susceptibilities of many types of mycobacteria.

A mechanism of activation of the ATP.Mg-dependent protein phosphatase (FC.M) has been proposed (Jurgensen, S., Shacter, E., Huang, C. Y., Chock, P. B., Yang, S.-D., Vandenheede, J. R., and Merlevede, W. (1984) J. Biol. Chem. 259, 5864-5870) in which a transient phosphorylation by the kinase FA of the modulator subunit (M) is the driving force for the transition of the inactive catalytic subunit (FC) into its active conformation. Incubation of FC.M with kinase FA and Mg2+ and adenosine 5'-(gamma-thio)triphosphate results in thiophosphorylation of M and also a conformational change in the phosphatase catalytic subunit; however, the enzyme remains inactive. Proteolysis of this inactive, thiophosphorylated complex causes proteolytic destruction of the modulator subunit and yields an active phosphorylase phosphatase species. Similar treatment of the native inactive enzyme does not yield active phosphatase. Evidence is presented, suggesting that a molecule of modulator is bound at an "inhibitory site" on the native enzyme. This modulator does not prevent the conformational change in the phosphatase catalytic subunit upon incubation with kinase FA and ATP.Mg but does partially inhibit the expression of the phosphorylase phosphatase activity.

The mechanism of activation of the Mg(II) X ATP-dependent phosphatase by the kinase FA has been investigated. The inactive protein phosphatase can be represented as FC X M where FC is the inactive catalytic component and M is the heat-stable modulator protein (also known as inhibitor-2). Phosphorylation of the modulator protein is demonstrated during activation of FC X M. In addition, continuous ATP hydrolysis during the activation is observed. This suggests that a cyclic phosphorylation-dephosphorylation reaction is continuously occurring during the activation. It is proposed that phosphorylation of the modulator protein causes an isomerization in FC to generate an active phosphatase. The activated phosphatase is capable of dephosphorylating the phosphorylated modulator. Upon dephosphorylation of modulator, the active phosphatase returns to its inactive form via a slow isomerization.