Fallon, John P. and Reeves, Emer P. and Kavanagh, Kevin (2011) The Aspergillus fumigatus toxin fumagillin suppresses the immune response of Galleria mellonella larvae by inhibiting the action of haemocytes. Microbiology, 157 (5). pp. 1481-1488. ISSN 1465-2080

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Abstract

Larvae of Galleria mellonella are widely used to evaluate microbial virulence and to assess the in vivo efficacy of antimicrobial agents. The aim of this work was to examine the ability of an Aspergillus fumigatus toxin, fumagillin, to suppress the immune response of larvae. Administration of fumagillin to larvae increased their susceptibility to subsequent infection with A. fumigatus conidia (P50.0052). It was demonstrated that a dose of 2 mg fumagillin ml”1 reduced the ability of insect immune cells (haemocytes) to kill opsonized cells of Candida albicans (P50.039) and to phagocytose A. fumigatus conidia (P50.016). Fumagillin reduced the oxygen uptake of haemocytes and decreased the translocation of a p47 protein which is homologous to p47phox, a protein essential for the formation of a functional NADPH oxidase complex required for superoxide production. In addition, toxin-treated haemocytes showed reduced levels of degranulation as measured by the release of a protein showing reactivity to an anti-myeloperoxidase antibody (P,0.049) that was subsequently identified by liquid chromatography-MS analysis as prophenoloxidase. This work demonstrates that fumagillin suppresses the immune response of G. mellonella larvae by inhibiting the action of haemocytes and thus renders the larvae susceptible to infection. During growth of the fungus in the larvae, this toxin, along with others, may facilitate growth by suppressing the cellular immune response.

Item Type:	Article
Additional Information:	© 2011 SGM. The definitive version of this article is available at DOI 10.1099/mic.0.043786-0
Keywords:	Aspergillus fumigatus; toxins; fumagillin; immune response; Galleria mellonella larvae; haemocytes; antimicrobial agents;
Academic Unit:	Faculty of Science and Engineering > Biology
Item ID:	4093
Depositing User:	Dr. Kevin Kavanagh
Date Deposited:	23 Jan 2013 16:10
Journal or Publication Title:	Microbiology
Publisher:	Society for General Microbiology
Refereed:	Yes
URI:	http://mic.sgmjournals.org/
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

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