AAV vector distribution in the mouse respiratory tract following four different methods of administration.

Background: Targeted delivery of gene therapy vectors to the mouse respiratory tract is often performed via intranasal or intratracheal administration; however, there can be a great deal of variability between these methods, which could potentially influence experimental results. Improving the accuracy and precision of lung delivery will not only reduce the number of animals required to detect statistically significant differences, but may reduce the variability of studies from different laboratories.

Results: Here we evaluated three different methods of adeno-associated virus (AAV) vector administration to the respiratory tract in mice (intranasal, intubation, and intratracheal injection) and discuss the advantages, challenges, and shortcomings of each.

Truncation of the enzootic nasal tumor virus envelope protein cytoplasmic tail increases Env-mediated fusion and infectivity.

Enzootic nasal tumor virus (ENTV) and Jaagsiekte sheep retrovirus (JSRV) are highly related ovine betaretroviruses that induce nasal and lung tumours in small ruminants, respectively. While the ENTV and JSRV envelope (Env) glycoproteins mediate virus entry using the same cellular receptor, the glycosylphosphatidylinositol-linked protein hyaluronoglucosaminidase, ENTV Env pseudovirions mediate entry into cells from a much more restricted range of species than do JSRV Env pseudovirions. Unlike JSRV Env, ENTV Env does not induce cell fusion at pH 5.

Analysis of the Choristoneura fumiferana nucleopolyhedrovirus genome.

The double-stranded DNA genome of Choristoneura fumiferana nucleopolyhedrovirus (CfMNPV) was sequenced and analysed in the context of other group I nucleopolyhedroviruses (NPVs). The genome consists of 129,593 bp with a G + C content of 50.1 mol%.

Choristoneura fumiferana nucleopolyhedrovirus encodes a functional 3'-5' exonuclease.

The Choristoneura fumiferana nucleopolyhedrovirus (CfMNPV) encodes an ORF homologous to type III 3'-5' exonucleases. The CfMNPV v-trex ORF was cloned into the Bac-to-Bac baculovirus expression-vector system, expressed in insect Sf21 cells with an N-terminal His tag and purified to homogeneity by using Ni-NTA affinity chromatography. Biochemical characterization of the purified V-TREX confirmed that this viral protein is a functional 3'-5' exonuclease that cleaves oligonucleotides from the 3' end in a stepwise, distributive manner, suggesting a role in proofreading during viral DNA replication and DNA repair.