Isolation of a natural DNA virus of <i>Drosophila melanogaster</i>, and characterisation of host resistance and immune responses

<div><p><i>Drosophila melanogaster</i> has played a key role in our understanding of invertebrate immunity. However, both functional and evolutionary studies of host-virus interaction in <i>Drosophila</i> have been limited by a dearth of native virus isolates. In particular, despite a long history of virus research, DNA viruses of <i>D</i>. <i>melanogaster</i> have only recently been described, and none have been available for experimental study. Here we report the isolation and comprehensive characterisation of Kallithea virus, a large double-stranded DNA virus, and the first DNA virus to have been reported from wild populations of <i>D</i>. <i>melanogaster</i>. We find that Kallithea virus infection is costly for adult flies, reaching high titres in both sexes and disproportionately reducing survival in males, and movement and late fecundity in females. Using the <i>Drosophila</i> Genetic Reference Panel, we quantify host genetic variance for virus-induced mortality and viral titre and identify candidate host genes that may underlie this variation, including <i>Cdc42-interacting protein 4</i>. Using full transcriptome sequencing of infected males and females, we examine the transcriptional response of flies to Kallithea virus infection and describe differential regulation of virus-responsive genes. This work establishes Kallithea virus as a new tractable model to study the natural interaction between <i>D</i>. <i>melanogaster</i> and DNA viruses, and we hope it will serve as a basis for future studies of immune responses to DNA viruses in insects.</p></div

Nucleases as a barrier to gene silencing in the cotton boll weevil, Anthonomus grandis.

Made available in DSpace on 2018-01-04T23:23:41Z (GMT). No. of bitstreams: 1 journal.pone.0189600.pdf: 7131320 bytes, checksum: ece3da5d8a008843e58701868100618d (MD5) Previous issue date: 2018-01-04bitstream/item/170309/1/journal.pone.0189600.pd

Impact of 3D cell culture on bone regeneration potential of mesenchymal stromal cells

As populations age across the world, osteoporosis and osteoporosis-related fractures are becoming the most prevalent degenerative bone diseases. More than 75 million patients suffer from osteoporosis in the US, the EU and Japan. Furthermore, it is anticipated that the number of patients affected by osteoporosis will increase by a third by 2050. Although conventional therapies including bisphosphonates, calcitonin and oestrogen-like drugs can be used to treat degenerative diseases, they are often associated with serious side effects including the development of oesophageal cancer, ocular inflammation, severe musculoskeletal pain, and osteonecrosis of the jaw. The use of autologous mesenchymal stromal cells/mesenchymal stem cells (MSCs) is a possible alternative therapeutic approach to tackle osteoporosis while overcoming the limitations of traditional treatment options. However, osteoporosis can cause a decrease in the numbers of MSCs, induce their senescence, and lower their osteogenic differentiation potential. Three-dimensional (3D) cell culture is an emerging technology that allows a more physiological expansion and differentiation of stem cells compared to cultivation on conventional flat systems. This review will discuss current understanding of the effects of different 3D cell culture systems on proliferation, viability, osteogenic differentiation, as well as on the immunomodulatory and anti-inflammatory potential of MSCs