A single administration of morpholino antisense oligomer rescues spinal muscular atrophy in mouse

Spinal Muscular Atrophy (SMA) is an autosomal recessive disorder characterized by α-motor neuron loss in the spinal cord anterior horn. SMA results from deletion or mutation of the Survival Motor Neuron 1 gene (SMN1) and retention of SMN2. A single nucleotide difference between SMN1 and SMN2 results in exclusion of exon 7 from the majority of SMN2 transcripts, leading to decreased SMN protein levels and development of SMA. A series of splice enhancers and silencers regulate incorporation of SMN2 exon 7; these splice motifs can be blocked with antisense oligomers (ASOs) to alter SMN2 transcript splicing. We have evaluated a morpholino oligomer against ISS-N1 (HSMN2Ex7D(-10,-29)), and delivered this morpholino (MO) to postnatal day 0 (P0) SMA pups (Smn -/-, SMN2+/+, SMN∆7 +/+) by intracerebroventricular (ICV) injection. Survival was increased markedly from 15 days to over 100 days. Delayed CNS MO injection has moderate efficacy, and delayed peripheral injection has mild survival advantage, suggesting that early CNS ASO administration is essential for SMA therapy consideration. ICV treatment increased full-length SMN2 transcript as well as SMN protein in neural tissue, but only minimally in peripheral tissue. Interval analysis shows a decrease in alternative splice modification over time. We suggest that CNS increases of SMN will have a major impact on SMA, and an early increase of SMN level results in correction of motor phenotypes. Last, the early introduction by intrathecal delivery of morpholino oligomers is a potential treatment for SMA patients

CONVERSION OF INDUCTION HEATING DEPOSITED MONETITE COATING TO HYDROXYAPATITE COATING ON HT–C/C COMPOSITES BY HYDROTHERMAL TREATMENT IN KOH AQUEOUS/AMMONIA SOLUTION

Carbon/carbon composites with hydroxyapatite coatings are one of the attractive materials in the dental and orthopedic fields. In this study, hydrothermal treatment, in KOH aqueous and ammonia solutions, was used to convert an induction-heating-deposited monetite coating to an adherent HA coating on H2O2 treated C/C composites. The structure, morphology and chemical composition of the as-received HA coatings were characterized by XRD, FTIR, SEM and EDS. A scratch test was conducted to measure the adhesion of HA coatings to HT–C/C substrate. The results show that well-crystallized carbonate hydroxyapatite coatings could be achieved under the two reaction mediums. However, the as-obtained HA coatings after KOH hydrothermal treatment have higher crystallinity and Ca/P ratio than those after ammonia hydrothermal treatment, and reveal an average critical load of 29 N which is more than two times as high as that for HA coatings after ammonia hydrothermal treatment.Carbon/carbon composites, hydroxyapatite, coating, hydrothermal treatment, scratch test

Improving single injection CSF delivery of AAV9-mediated gene therapy for SMA: A dose-response study in mice and nonhuman primates

Spinal muscular atrophy (SMA) is the most frequent lethal genetic neurodegenerative disorder in infants. The disease is caused by low abundance of the survival of motor neuron (SMN) protein leading to motor neuron degeneration and progressive paralysis. We previously demonstrated that a single intravenous injection (IV) of self-complementary adeno-associated virus-9 carrying the human SMN cDNA (scAAV9-SMN) resulted in widespread transgene expression in spinal cord motor neurons in SMA mice as well as nonhuman primates and complete rescue of the disease phenotype in mice. Here, we evaluated the dosing and efficacy of scAAV9-SMN delivered directly to the cerebral spinal fluid (CSF) via single injection. We found widespread transgene expression throughout the spinal cord in mice and nonhuman primates when using a 10 times lower dose compared to the IV application. Interestingly, in nonhuman primates, lower doses than in mice can be used for similar motor neuron targeting efficiency. Moreover, the transduction efficacy is further improved when subjects are kept in the Trendelenburg position to facilitate spreading of the vector. We present a detailed analysis of transduction levels throughout the brain, brainstem, and spinal cord of nonhuman primates, providing new guidance for translation toward therapy for a wide range of neurodegenerative disorders

Correlation of clinical and deletion data in Duchenne and Becker muscular dystrophy.

Cloned cDNA sequences representing exons from the Duchenne/Becker muscular dystrophy (DMD/BMD) gene were used for deletion screening in a population of 287 males males affected with DMD or BMD. The clinical phenotypes of affected boys were classified into three clinical severity groups based on the age at which ambulation was lost. Boys in group 1 had DMD, losing ambulation before their 13th birthday; those in group 2 had disease of intermediate severity, losing ambulation between the ages of 13 and 16 years; and boys in group 3 had BMD, being ambulant beyond 16 years. A fourth group consisted of patients too young to be classified. Clinical group allocation was made without previous knowledge of the DNA results. A gene deletion was found in 124 cases where the clinical severity group of the affected boy was known. The extent of the deletions was delineated using cDNA probes. There were 74 different deletions. Fifty-five of these were unique to individual patients, but the other 19 were found in at least two unrelated patients. The different clinical groups showed generally similar distributions of deletions, and the number of exon bands deleted (that is, deletion size) was independent of phenotype. Some specific deletion types, however, correlated with the clinical severity of the disease. Deletion of exons containing HindIII fragments 33 and 34 and 33 to 35 were associated with BMD and were not found in patients with DMD. Deletions 3 to 7 occurred in four patients with the intermediate phenotype and one patient with BMD. Other shared deletions were associated with DMD, although in four cases patients with disease of intermediate severity apparently shared the same deletion with boys with DMD. The range of phenotypes observed, and the overlap at the genetic level between severe and intermediate and mild and intermediate forms of dystrophy, emphasizes the essential continuity of the clinical spectrum of DMD/BMD. There were no characteristic deletions found in boys with mental retardation or short stature which differed from deletions in affected boys without these features