Histone deacetylase inhibitors for purging HIV-1 from the latent reservoir.

Contains fulltext : 96985.pdf (publisher's version ) (Open Access)A reservoir of latently infected memory CD4(+) T cells is believed to be the source of HIV-1 reemergence after discontinuation of antiretroviral therapy. HIV-1 eradication may depend on depletion of this reservoir. Integrated HIV-1 is inaccessible for expression, in part because of histone deacetylases (HDACs). One approach is to exploit the ability of HDAC inhibitors to induce HIV-1 expression from an integrated virus. With effective antiretroviral therapy, newly expressed HIV-1 is incapable of reinfecting naive cells. With HIV-1 expression, one assumes the infected cell dies and there is a progressive reduction in the size of the reservoir. The concept was tested using the HDAC inhibitor valproic acid. However, valproic acid is weak in inducing HIV-1 from latency in vitro. As such, clinical trials revealed a small or no effect on reducing the number of latently infected T cells in the peripheral blood. However, the new HDAC inhibitors vorinostat, belinostat and givinostat are more effective at targeting specific HDACs for HIV-1 expression than valproic acid. Here, we review studies on HDAC inhibitor-induced expression of latent HIV-1, with an emphasis on new and specific HDAC inhibitors. With increased potency for HIV-1 expression as well as safety and ease of oral administration, new HDAC inhibitors offer a unique opportunity to deplete the latent reservoir. An additional benefit is the antiinflammatory properties of HDAC inhibitors, including downregulation of HIV-1 coreceptor expression

Cloning of the sulphamidase gene and identification of mutations in Sanfilippo A syndrome

Sanfilippo A syndrome is one of four recognised Sanfilippo sub-types (A, B, C and D) that result from deficiencies of different enzymes involved in the lysosomal degradation of heparan sulphate; patients suffer from severe neurological disorders. The Sanfilippo syndrome sub-types are also known as mucopolysaccharidosis (MPS) type III (MPS-IIIA, B, C and D), and are part of the large group of lysosomal storage disorders. Each of the MPS-III types is inherited as an autosomal recessive disorder with considerable variation in severity of clinical phenotype. The incidence of Sanfilippo syndrome has been estimated at 1:24,000 in The Netherlands with MPS IIIA (MIM #252900) the most common. MPS-IIIA is the predominant MPS-III in the United Kingdom, and has a similar high incidence to that found in The Netherlands (E. Wraith, personal communication). There is a particularly high incidence of a clinically severe form of MPS-IIIA in the Cayman Islands with a carrier frequency of 0.1 (ref. 4). Due to the mild somatic disease compared to other MPS disorders there is difficulty in diagnosing mild cases of MPS-III, hence Sanfilippo syndrome may be underdiagnosed, especially in patients with mild mental retardation. Here, we report the isolation, sequence and expression of cDNA clones encoding the enzyme sulphamidase (EC 3.10.1.1). In addition, we report the chromosomal localisation of the sulphamidase gene as being 17q25.3. An 11-bp deletion, present in sulphamidase cDNA from two unrelated Sanfilippo A patients, is described.Hamish S. Scott ; Lianne Blanch ; Xiao-hui Guo ; Craig Freeman ; Annette Orsborn ; Elizabeth Baker ; Grant R. Sutherland ; C. Phillip Morris ; John J. Hopwoo