Characterization of hepatitis B virus in Turkish blood donors, and the prevalence of the SP1 splice variant.

Hepatitis B is a disease of the liver that can manifest acutely, or persist chronically as a result of infection with the hepatitis B virus (HBV). Turkey has a moderate endemicity level of HBV infection, and all data published to date has shown this to be of genotype D, predominantly of subgenotype D1. However the sequences of very few full genomes have been published. The aim of this study was to characterize the molecular profile of hepatitis B virus in asymptomatic, first-time Turkish blood donors. The results confirm that genotype D, subgenotype D1 is the most prevalent HBV strain in Turkey, accounting for 94% of cases. Subgenotypes D2 and D3 were present as minority strains (4% and 2%, respectively). A singly spliced HBV variant that is capable of forming defective HBV particles and has been associated with apoptosis and activation of T-cell responses was also detected in 52.5% of samples screened, co-circulating with wild type genomes.

Contrasting effects of cerebrospinal fluid from motor neuron disease patients on the survival of primary motor neurons cultured with or without glia.

Motor neuronal (MN) degeneration in motor neuron disease (MND) often starts focally before spreading to neighbouring MN populations, suggesting soluble factors may contribute to disease propagation. Whether cerebrospinal fluid (CSF) from MND patients contains such factors has been difficult to prove. We aimed to determine the effect of glia on the response of MNs to CSF from MND patients. Primary rat spinal MNs grown in mono-culture or cocultured with glia were exposed to CSF from patients (MND-CSF) or controls (Con-CSF) and survival measured by cell counting. In mono-culture both MND-CSF and Con-CSF reduced MN survival with MND-CSF reducing MN survival by less than Con-CSF. In coculture MN survival was unchanged by exposure to MND-CSF while exposure to Con-CSF improved MN survival. In separate experiments, murine MNs grown in mono-culture and stressed by growth factor withdrawal were partially rescued by the application of monocyte chemoattractant protein-1 (MCP-1), a trophic factor previously found to be elevated in MND-CSF. Our results suggest that MND-CSF may contain factors harmful to MNs as well as factors protective of MNs, the interplay of which is altered by the presence of glial cells. These preliminary results further emphasize the importance of MN environment to MN health.

Mutations in CHMP2B in lower motor neuron predominant amyotrophic lateral sclerosis (ALS).

BACKGROUND: Amyotrophic lateral sclerosis (ALS), a common late-onset neurodegenerative disease, is associated with fronto-temporal dementia (FTD) in 3-10% of patients. A mutation in CHMP2B was recently identified in a Danish pedigree with autosomal dominant FTD. Subsequently, two unrelated patients with familial ALS, one of whom also showed features of FTD, were shown to carry missense mutations in CHMP2B. The initial aim of this study was to determine whether mutations in CHMP2B contribute more broadly to ALS pathogenesis. METHODOLOGY/PRINCIPAL FINDINGS: Sequencing of CHMP2B in 433 ALS cases from the North of England identified 4 cases carrying 3 missense mutations, including one novel mutation, p.Thr104Asn, none of which were present in 500 neurologically normal controls. Analysis of clinical and neuropathological data of these 4 cases showed a phenotype consistent with the lower motor neuron predominant (progressive muscular atrophy (PMA)) variant of ALS. Only one had a recognised family history of ALS and none had clinically apparent dementia. Microarray analysis of motor neurons from CHMP2B cases, compared to controls, showed a distinct gene expression signature with significant differential expression predicting disassembly of cell structure; increased calcium concentration in the ER lumen; decrease in the availability of ATP; down-regulation of the classical and p38 MAPK signalling pathways, reduction in autophagy initiation and a global repression of translation. Transfection of mutant CHMP2B into HEK-293 and COS-7 cells resulted in the formation of large cytoplasmic vacuoles, aberrant lysosomal localisation demonstrated by CD63 staining and impairment of autophagy indicated by increased levels of LC3-II protein. These changes were absent in control cells transfected with wild-type CHMP2B. CONCLUSIONS/SIGNIFICANCE: We conclude that in a population drawn from North of England pathogenic CHMP2B mutations are found in approximately 1% of cases of ALS and 10% of those with lower motor neuron predominant ALS. We provide a body of evidence indicating the likely pathogenicity of the reported gene alterations. However, absolute confirmation of pathogenicity requires further evidence, including documentation of familial transmission in ALS pedigrees which might be most fruitfully explored in cases with a LMN predominant phenotype.