Special Issue “Evolution and Diversity of Insect Viruses”

Insects are crucial for ecosystem functions and services and directly influence human well-being and health [...]

Horizontally transmitted parasitoid killing factor shapes insect defense to parasitoids

Interkingdom competition occurs between hymenopteran parasitoids and insect viruses sharing the same insect hosts. It has been assumed that parasitoid larvae die with the death of the infected host or as result of competition for host resources. Here we describe a gene family, parasitoid killing factor (pkf), that encodes proteins toxic to parasitoids of the Microgastrinae group and determines parasitism success. Pkfs are found in several entomopathogenic DNA virus families and in some lepidopteran genomes. We provide evidence of equivalent and specific toxicity against endoparasites for PKFs found in entomopoxvirus, ascovirus, baculovirus, and Lepidoptera through a mechanism that elicits apoptosis in the cells of susceptible parasitoids. This highlights the evolutionary arms race between parasitoids, viruses, and their insect hosts.

Special Issue “Transmission Dynamics of Insect Viruses”

At the close of this Special Issue of Viruses on the Transmission Dynamics of Insect Viruses, we would like to thank all of the authors for their submissions and the great work expanding our knowledge of insect virus biology and transmission [...]

Special Issue “Insect Viruses and Pest Management”

Most revues consider the work on Lymantria monarcha in central Europe [...]

Metagenomic Analysis of the Virome in Lung Tissues and Guts of Wild Mice

Background Mice, as host animals of a variety of pathogens, can spread 60 kinds of human diseases including more than ten families of viruses including Poxviridae, Herpesviridae, and so on. Methods In this study, lung tissues and gut samples of 7-week-old mice from outdoor environments were sequenced using metagenomics, and an abundance of virome information was acquired. Results A total of 82 families of mammalian viruses, plant viruses, insect viruses, and phages were detected. Among the top 10 most abundant families were the RNA viruses Orthomyxoviridae, Picornaviridae, Bunyaviridae, and Arenaviridae, the DNA virus Herpesviridae, the insect viruses Nodaviridae and Baculoviridae, the plant virus Tombusviridae, and the phage Myoviridae. Except for Myoviridae, whose abundance in guts was higher than in lung tissues, the abundance of viruses in the lung tissues and guts showed no significant difference. Conclusions The data obtained in this study provided an overview of the viral community present in these mice samples, revealing some mouse-associated viruses closely related to known human or animal pathogens. Strengthening our understanding of unclassified viruses in mice in the natural environment could provide scientific guidance for the prevention and control of new viral outbreaks that can spread via rodents.

Photochemical Treatment of Drosophila APCs Can Eliminate Associated Viruses and Maintain the APC Function for Generating Antigen-Specific CTLs Ex Vivo

Drosophila cells transfected with MHC class I and a number of costimulation molecules including B7.1, ICAM, LFA-3, and CD70 are potent antigen-presenting cells (APCs) for the generation of antigen-specific cytotoxic T cells (CTLs) in vitro. Using Drosophila APCs, CTLs specific for melanoma antigens have been generated in vitro and adoptively transferred to melanoma patients. However, the recent discovery that Drosophila cells can carry insect viruses raises the potential risk of Drosophila APCs transmitting xenogenic viruses to patient CTLs. In this study, we have investigated photoreactive methods to inactivate insect viruses in APC. A clinical grade psoralen compound, 8-MOP (UVADEX) in combination with UVA treatment (5 joules/cm2) can be used to inactivate Drosophila cell viruses. UVADEX treatment is sufficient to inactivate insect viruses but does not affect the expression of MHC class I molecules and costimulation molecules on Drosophila APCs. In fact, UVADEX treatment prevents Drosophila APC growth while maintaining APC function. Furthermore, UVADEX-treated Drosophila APCs maintain or have enhanced APC function as determined by enhanced T cell activation, proliferation, and CTL generation. Thus, the use of UVADEX-treated Drosophila APCs may provide a valuable tool for immunotherapy to generate tumor antigen-specific CTLs.