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Abstract Representatives of the genusAnncaliiaare known as natural parasites of dipteran and coleopteran insects, amphipod crustaceans, but also humans, primarily with immunodeficiency.Anncaliia algerae‐caused fatal myositis is considered as an emergent infectious disease in humans.A. (=Nosema, Brachiola) algerae, the best studied species of the genus, demonstrates the broadest among microsporidia range of natural and experimental hosts, but it has never been propagated inDrosophila. We present ultrastructural analysis of development ofA. algeraein visceral muscles and adipocytes ofDrosophila melanogaster2 wk after per oral experimental infection. We observed typical toAnncaliiaspp. features of ultrastructure and cell pathology including spore morphology, characteristic extensions of the plasma membrane, and presence of “ridges” and appendages of tubular material at proliferative stages.Anncaliia algeraedevelopment inD. melanogasterwas particularly similar to one ofA. algeraeandA.(Brachiola) vesicularumin humans with acute myositis. GivenD. melanogasteris currently the most established genetic model, with a fully sequenced genome and easily available transgenic forms and genomic markers, a novel host–parasite system might provide new genetic tools to investigate host–pathogen interactions ofA. algerae, as well to test antimicrosporidia drugs.
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Pathogen‐ and host‐directed pharmacologic strategies for control of Vairimorpha (Nosema) spp. infection in honey bees
Abstract Microsporidia are obligate intracellular parasites of the Fungal Kingdom that cause widespread infections in nature, with important effects on invertebrates involved in food production systems. The two microsporidian speciesVairimorpha (Nosema) ceranae(and the less commonVairimorpha (Nosema) apis) can cause individual disease in honey bees and contribute to colony collapse. The efficacy, safety, and availability of fumagillin, the only drug currently approved to treat microsporidia infection in bees, is uncertain. In this review, we will discuss some of the most promising alternative strategies for the mitigation ofVairimorphaspp. with an emphasis on infection byV. ceranae, now the dominant species infecting bees. We will focus on pharmacologic interventions where the mechanism of action is known and examine both pathogen‐directed and host‐directed approaches. As limiting toxicity to host cells has been especially emphasized in treating bees that are already facing numerous stressors, strategies that disrupt pathogen‐specific targets may be especially advantageous. Therefore, efforts to increase the knowledge and tools for facilitating the discovery of such targets and pharmacologic agents directed against them should be prioritized.
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- Award ID(s):
- 2243451
- PAR ID:
- 10498996
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Eukaryotic Microbiology
- Volume:
- 71
- Issue:
- 5
- ISSN:
- 1066-5234
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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