Long-term phenotypic correction in factor IX knockout mice by using ΦC31 integrase-mediated gene therapy.

Hemophilia B, a hereditary bleeding disorder caused by a deficiency of coagulation factor IX (FIX), is an excellent candidate for gene therapy. However, to date, success in hemophilia gene therapy clinical trials has been limited due to failure to achieve or sustain therapeutic levels of factor expression. The ΦC31 integrase system efficiently integrates plasmid DNA carrying a transgene and an attB site into a limited number of endogenous pseudo attP sites in mammalian genomes, leading to robust, sustained transgene expression. A strategy utilizing plasmid DNA integrated with ΦC31 integrase may offer a facile and safe alternative for sustained human FIX (hFIX) expression. Hydrodynamic tail vein injection was used for delivery of plasmids encoding ΦC31 integrase and hFIX to the liver of FIX knockout mice. We demonstrated prolonged therapeutic levels of hFIX in this knockout mouse model of hemophilia B over a 6-month time course when ΦC31 integrase was used. Additionally, we observed sustained FIX activity in plasma and phenotypic correction of bleeding after tail clip in ΦC31-treated mice. In the livers that received integrase, we also demonstrated prolonged hFIX expression in hepatocytes by immunohistochemistry and documented sequence-specific genomic integration of the hFIX plasmid. These studies suggest the possibility that a similar approach in large animals and humans could lead to a simple and successful gene therapy for hemophilia.

Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt object.

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.

Genetic and antigenic diversity among eastern equine encephalitis viruses from North, Central, and South America.

Eastern equine encephalitis virus (EEEV), the sole species in the EEE antigenic complex, is divided into North and South American antigenic varieties based on hemagglutination inhibition tests. Here we describe serologic and phylogenetic analyses of representatives of these varieties, spanning the entire temporal and geographic range available. Nucleotide sequencing and phylogenetic analyses revealed additional genetic diversity within the South American variety; 3 major South/Central American lineages were identified including one represented by a single isolate from eastern Brazil, and 2 lineages with more widespread distributions in Central and South America. All North American isolates comprised a single, highly conserved lineage with strains grouped by the time of isolation and to some extent by location. An EEEV strain isolated during a 1996 equine outbreak in Tamaulipas State, Mexico was closely related to recent Texas isolates, suggesting southward EEEV transportation beyond the presumed enzootic range. Plaque reduction neutralization tests with representatives from the 4 major lineages indicated that each represents a distinct antigenic subtype. A taxonomic revision of the EEE complex is proposed.

Highly pathogenic avian influenza A/H7N3 in great-tailed grackles (Quiscalus mexicanus) in the Altos de Jalisco region of Mexico.

INTRODUCTION: In June 2012, the presence of a severe highly pathogenic avian influenza (HPAI) outbreak produced by an influenza type A, subtype H7N3 (A/H7N3) virus was reported in Mexico, which significantly affected the region of Los Altos de Jalisco, the most important table-egg production zone in Mexico. CASE PRESENTATION: To the best of our knowledge, this is the first report describing the occurrence of infection in wild endemic birds, and particularly in the great-tailed grackle (Quiscalus mexicanus), by an HPAI A/H7N3 orthomyxovirus, during the avian influenza epizootic, which occurred in June-October 2012, in the Los Altos region of Jalisco, Mexico, a highly significant poultry area. The great-tailed grackle population has increased significantly due to intense agricultural and livestock farming expansion throughout North and Central America and northern South America, in diverse ecological systems. The great-tailed grackle's infectious/epidemiological role is unknown, as is its role as the avian influenza virus reservoir and as disseminator of other infectious diseases. CONCLUSION: Because of the huge impact that avian influenza virus has on food production, on the economic activity of the affected areas and on the public health of animal and human populations, it is necessary to further investigate the significance of a wild population existing in the vicinity of industrial poultry farms and backyard poultry operations.