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International audience; A new bone tissue process using supercritical carbon dioxide extraction has been checked for viral inactivation and allografts, thus processed, for bone integration. Four viruses, human immunodeficiency virus type I (HIV-I), Sindbis virus, Polio Sabin type-I virus, and Pseudorabies virus (PRV) and four processing stages, supercritical CO2, hydrogen peroxide, sodium hydroxide and ethanol treatments were tested. The cumulated reduction factors (log10) were the following: >18.2 for Sindbis virus, >24.4 for polio virus, >17.6 for PRV and >14.2 for HIV-I. Such processed allografts were implanted into sheep leading to a much faster osseointegration in comparison with non-treated allografts. Better graft incorporation in addition to viral safety suggest that this process could become a new way for processing bank bones, alternatively or additionally, to the procedures presently used.

International audience; A new bone tissue process using supercritical fluid (SCF) technology has recently been described (Fages et al. 1994). Due to their unique properties of diffusivity, density and viscosity, supercritical fluids are used as selective extraction solvents. They are particularly adapted for extraction of components entrapped in a solid microporous matrix, which is the case of bone tissue. Supercritical CO 2 extraction leads to a total range in-depth delipidation of the bone porosity. Three additional steps complete the bone processing: Hydrogen peroxide is used for protein and cellular debris elimination. Sodium hydroxide for the inactivation of potentially present prions, and ethanol for final cleansing and for its well-known virucidal properties.

Summary Background Mucopolysaccharidosis type IIIB syndrome (also known as Sanfilippo type B syndrome) is a lysosomal storage disease resulting in progressive deterioration of cognitive acquisition after age 2–4 years. No treatment is available for the neurological manifestations of the disease. We sought to assess the safety and efficacy of a novel intracerebral gene therapy. Methods Local regulatory authorities in France allowed inclusion of up to four children in this phase 1/2 study. Treatment was 16 intraparenchymal deposits (four in the cerebellum) of a recombinant adenoassociated viral vector serotype 2/5 (rAAV2/5) encoding human α-N-acetylglucosaminidase (NAGLU) plus immunosuppressive therapy. We assessed tolerance, neurocognitive progression, brain growth, NAGLU enzymatic activity in CSF, and specific anti-NAGLU immune response for 30 months after surgery. This trial is registered with EudraCT, number 2012-000856-33, and the International Standard Clinical Trial Registry, number ISRCTN19853672. Findings Of seven eligible children, the four youngest, from France (n=2), Italy (n=1), and Greece (n=1), aged 20, 26, 30, and 53 months, were included between February, 2012, and February, 2014. 125 adverse events were recorded, of which 117 were treatment emergent and included six classified as severe, but no suspected unexpected serious adverse drug reactions were seen. Vector genomes were detected in blood for 2 days after surgery. Compared with the natural history of mucopolysaccharidosis type III syndromes, neurocognitive progression was improved in all patients, with the youngest patient having function close to that in healthy children. Decrease in developmental quotient was −11·0 points in patient one, −23·0 in patient two, −29·0 in patient three, and −17·0 in patient four, compared with −37·7 in the natural history of the disease. NAGLU activity was detected in lumbar CSF and was 15–20% of that in unaffected children. Circulating T lymphocytes that proliferated and produced tumour necrosis factor α upon ex-vivo exposure to NAGLU antigens were detectable at 1–12 months and 3–12 months, respectively, but not at 30 months in three of four patients. Interpretation Intracerebral rAVV2/5 was well tolerated and induced sustained enzyme production in the brain. The initial specific anti-NAGLU immune response that later subsided suggested acquired immunological tolerance. The best results being obtained in the youngest patient implies a potential window of opportunity. Longer follow-up is needed to further assess safety outcomes and persistence of improved cognitive development. Funding Association Francaise Contre les Myopathies, Vaincre les Maladies Lysosomales, Institut Pasteur, and UniQure.