F. Bianchi

Combined gene/cell therapies provide long-term and pervasive rescue of multiple pathological symptoms in a murine model of globoid cell leukodystrophy

Globoid cell leukodystrophy (GLD) is a lysosomal storage disease caused by deficient activity of β-galactocerebrosidase (GALC). The infantile forms manifest with rapid and progressive central and peripheral demyelination, which represent a major hurdle for any treatment approach. We demonstrate here that neonatal lentiviral vector-mediated intracerebral gene therapy (IC GT) or transplantation of GALC-overexpressing neural stem cells (NSC) synergize with bone marrow transplant (BMT) providing dramatic extension of lifespan and global clinical–pathological rescue in a relevant GLD murine model. We show that timely and long-lasting delivery of functional GALC in affected tissues ensured by the exclusive complementary mode of action of the treatments underlies the outstanding benefit. In particular, the contribution of neural stem cell transplantation and IC GT during the early asymptomatic stage of the disease is instrumental to enhance long-term advantage upon BMT. We clarify the input of central nervous system, peripheral nervous system and periphery to the disease, and the relative contribution of treatments to the final therapeutic outcome, with important implications for treatment strategies to be tried in human patients. This study gives proof-of-concept of efficacy, tolerability and clinical relevance of the combined gene/cell therapies proposed here, which may constitute a feasible and effective therapeutic opportunity for children affected by GLD.

Loss of Fig4 in both Schwann cells and motor neurons contributes to CMT4J neuropathy

Mutations of FIG4 are responsible for Yunis-Varón syndrome, familial epilepsy with polymicrogyria, and Charcot-Marie-Tooth type 4J neuropathy (CMT4J). Although loss of the FIG4 phospholipid phosphatase consistently causes decreased PtdIns(3,5)P2 levels, cell-specific sensitivity to partial loss of FIG4 function may differentiate FIG4-associated disorders. CMT4J is an autosomal recessive neuropathy characterized by severe demyelination and axonal loss in human, with both motor and sensory involvement. However, it is unclear whether FIG4 has cell autonomous roles in both motor neurons and Schwann cells, and how loss of FIG4/PtdIns(3,5)P2-mediated functions contribute to the pathogenesis of CMT4J. Here, we report that mice with conditional inactivation of Fig4 in motor neurons display neuronal and axonal degeneration. In contrast, conditional inactivation of Fig4 in Schwann cells causes demyelination and defects in autophagy-mediated degradation. Moreover, Fig4-regulated endolysosomal trafficking in Schwann cells is essential for myelin biogenesis during development and for proper regeneration/remyelination after injury. Our data suggest that impaired endolysosomal trafficking in both motor neurons and Schwann cells contributes to CMT4J neuropathy.

Sensory tricks and brain excitability in cervical dystonia: A transcranial magnetic stimulation study

Sensory tricks such as touching the face with fingertips often improve cervical dystonia [CD]. This study is to determine whether sensory tricks modulate motor cortex excitability, assessed by paired‐pulse transcranial magnetic stimulation [p‐pTMS].

Rituximab in refractory chronic inflammatory demyelinating polyradiculoneuropathy: report of four cases

Dear Sirs, Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare disorder causing progressive or relapsing weakness and sensory disturbances [1]. CIDP is sustained by both humoral and cell-mediated immunity directed against myelin sheath antigens [2]. First-line treatments include corticosteroids, intravenous immunoglobulins (IVIg), and plasma exchange that are effective in about 80% of patients [3]. Unresponsive patients are treated with other immunosuppressive and immunomodulatory drugs. Four randomized trials and many observational studies of these drugs have been performed but are inconclusive [4]. We provide additional data supporting the efficacy of rituximab even in severely compromised patients who did not respond to firstor second-line treatments. We treated with rituximab four severe CIDP patients, after proven ineffectiveness of firstor other second-line drugs, or wishing to spare steroid in a young severely affected patient, experiencing significant side effects. Diagnostic category was definite CIDP for all patients, following EFNS/PNS guidelines [5]. The study was approved by the ethics committee of San Raffaele Hospital and all patients gave written informed consent to off-label rituximab treatment. Table 1 summarizes demographic and clinical characteristics of our cohort. A comparison of the standard nerve conduction parameters between the preand post-treatment follow-up examinations was performed. Moreover, a nerve conduction velocity (NCV) index was assessed, to allow an easier longitudinal evaluation. NCV index was calculated as previously reported [6]. Briefly, conduction velocities of four nerves were considered (i.e., motor conduction velocity of deep peroneal and ulnar nerve; sensory conduction velocity of sural nerve and wrist-finger segment of the median nerve) to obtain nerve NCV Z scores [(patient’s NCV value mean NCV value in control healthy subjects)/standard deviation (SD) of the same nerve in control healthy subjects]. The patient’s NCV index was the mean of the NCV Z scores of all nerves considered. Neurological assessment was performed on each treatment cycle. All patients showed marked amelioration in terms of limbs’ strength, measured by MRC sum score, and disability, evaluated through INCAT score (Table 2). The interval between rituximab first cycle and the beginning of clinical recovery was very short for all patients; in the second patient, rituximab mainly acted as a steroid-sparing drug (patient could discontinue oral steroids 6 months after first rituximab infusion, maintaining stable disease). Table 2 also shows a consistent B-cell pool depletion. The second patient was excluded from neurophysiological analysis, given the complete nerve unexcitability in all the assessments made. For the other patients, at least two examinations, one before (1 month) and one after starting therapy (6 months), were available. All patients had a neurophysiological improvement at the post-treatment studies (Table 3). All three patients had an NCV index value\2 at each investigation, consistent with an NCV score exceeding & Daniele Velardo velardo.daniele@gmail.com

Quantitative EMG of external urethral sphincter in neurologically healthy men with prostate pathology.

There are no data on quantitative electromyography (EMG) of the external urethral sphincter (EUS) in men. The aim of this study was to obtain reference data from a group of neurologically healthy continent men with prostate pathology using a standardized technique. Methods: Sixty‐six subjects without neurological disorders were included. Motor unit potential (MUP) and interference pattern (IP) analysis were performed using multi‐MUP and turns/amplitude techniques, respectively. Results: Of 66 patients, 51 (mean age, 65.17; SD, 6.70) had localized prostate cancer (PCa), and 15 (mean age 61.67, SD 6.25) had benign prostate hyperplasia (BPH). Descriptive MUP parameters and IP‐clouds were obtained, respectively in the BPH and PCa groups. No group differences were found. Conclusions: This study provides quantitative EMG measures of EUS functionality in continent men with prostate pathology. The data could be used as reference values for patients undergoing prostate surgery to identify postoperative changes in EUS function possibly influencing continence. Muscle Nerve 50: 571–576, 2014

Enhanced axonal Neuregulin-1 type-III signaling ameliorates disease severity in a CMT1B mouse model

Charcot–Marie–Tooth neuropathies (CMTs) are a group of genetic disorders that affect the peripheral nervous system (PNS) with heterogeneous pathogenesis and no available treatment. Axonal Neuregulin 1 type III (Nrg1TIII) drives peripheral nerve myelination by activating downstream signaling pathways such as PI3K/Akt and MAPK/Erk that converge on master transcriptional regulators of myelin genes, such as Krox20. We reasoned that modulating Nrg1TIII activity may constitute a general therapeutic strategy to treat CMTs that are characterized by reduced levels of myelination. Here, we show that genetic overexpression of Nrg1TIII ameliorates neurophysiological and morphological parameters in a mouse model of demyelinating CMT1B, without exacerbating the toxic gain of function that underlies the neuropathy. Intriguingly, the mechanism appears not to be related to Krox20 or myelin gene upregulation, but rather to a beneficial rebalancing in the stoichiometry of myelin lipids and proteins. Finally, we provide proof of principle that stimulating Nrg1TIII signaling, by pharmacological suppression of the Nrg1TIII inhibitor TACE/ADAM17, also ameliorates the neuropathy. Thus, modulation of Nrg1TIII by TACE/ADAM17 inhibition may represent a general treatment for hypomyelinating neuropathies.

62. Sensory Tricks in cervical dystonia: A neurophysiological study with short latency afferent inhibition

A classic hallmark of cervical dystonia (CD) is the improvement of dystonic symptoms during a specific maneuver, defined ‘sensory trick’ (ST). Even if the mechanism by which ST improves dystonia is not well understood, it is likely that cortical sensorimotor integration processes are involved. In a previous preliminary study, we evaluated the short latency afferent inhibition (SAI) in a group of CD patients and the effects of ST on the SAI profile. To date, we have increased our sample including 28 patients with primary CD (18 with ST, CD+, and 10 without ST, CD-) and 11 controls. The analysis of variance showed no significant differences between CD- patients and controls. On the contrary, a remarkable trend toward a reduced SAI was observed in CD+ patients when they did not perform ST. Interestingly, SAI was further reduced in CD+ patients when they performed ST, reaching a strong statistical relevance. Our results show the presence of an abnormal sensorimotor integration in CD+ patients. Furthermore, they prove that ST acts by modulating the abnormal link between sensory input and motor output.

PD11-03 NEW APPROACH AND SET OF REFERENCE VALUES FOR QUANTITATIVE ELECTROMYOGRAPHIC ANALYSIS OF THE EXTERNAL URETHRAL SPHINCTER IN MEN

incontinence and detrusor overactivity (DO), standardization of terminology and protocol in urodynamics (UDS) is paramount. Variations may in part explain the discrepancies observed in trials involving UDS measurements. Our objective was to perform a meta-analysis on the effects of posture in the detection of DO using UDS in adult patients with lower urinary tract symptoms (LUTS). METHODS: Medline, Scopus, and ISI Web of Science databases were queried using specified search terms for articles written in English between 1963 and June 2013. References from the primary citations were manually checked to identify articles not captured. Studies were included if they investigated patients presenting with LUTS, controlled for any provocation maneuvers (e.g. cough provocation performed in both postures or no provocation performed in either posture), and if the study used the same cystometric technique for assessment in both postures. All data was extracted independently by 2 reviewers. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to assess bias of all included studies. The odds ratios (OR) and 95% confidence intervals (CI) for detecting DO were calculated for cystometry in an erect (sitting or standing) compared to supine posture. Effect size estimates of ORs were calculated using DerSirmonian and Laird random-effects models. RESULTS: An initial 175 articles were identified. A total of 9 articles (n1⁄41186 patients) met the inclusion criteria. In all 9 articles, the supine posture was compared with an erect posture. Cystometry in an erect posture was 3.38 times more likely to detect DO compared to the supine cystometry (OR: 3.38, 95% CI: 2.0-5.7, p<0.001). Standing cystometry was more likely to detect DO compared to sitting (OR: 1.46, 95% CI: 1.13-1.88, p1⁄40.003) and trended towards significance compared to the supine cystometry (OR: 3.58, 95% CI: 0.940-13.618, p1⁄40.062). When using erect cystometry as the reference standard, supine cystometry alone would miss nearly half of the cases of DO (47.4%, p<0.001). CONCLUSIONS: Cystometry in an erect posture significantly increases the odds of detecting DO. Moreover, standing cystometry is significantly more likely to detect DO compared to cystometry in the sitting posture. Given the dramatic substantial effect of patient posture on UDS outcomes, particular emphasis must be placed when interpreting UDS results. Trials involving UDS should adjust or control for posture in analyses and patient posture should be reported in trial results.