MURAL - Maynooth University Research Archive Library



    Susceptibility of Larvae of Galleria mellonella to Infection by Asperillus fumigatus is Dependent upon Stage of Conidial Germination


    Renwick, Julie and Daly, Paul and Reeves, Emer and Kavanagh, Kevin (2006) Susceptibility of Larvae of Galleria mellonella to Infection by Asperillus fumigatus is Dependent upon Stage of Conidial Germination. Mycopathologia, 161. pp. 377-384.

    [img] Download (326kB)


    Share your research

    Twitter Facebook LinkedIn GooglePlus Email more...



    Add this article to your Mendeley library


    Abstract

    The ability of conidia of the human pathogenic fungus Aspergillus fumigatus to kill larvae of the insect Galleria mellonella was investigated. Conidia at different stages of the germination process displayed variations in their virulence as measured using the Galleria infection model. Non-germinating (‘resting’) conidia were avirulent except when an inoculation density of 1 × 107 conidia per insect was used. Conidia that had been induced to commence the germination process by pre-culturing in growth medium for 3 h were capable of killing larvae at densities of 1 × 106 and 1 × 107 per insect. An inoculation density of 1 × 105 conidia per insect remained avirulent. Conidia in the outgrowth phase of germination (characterised as the formation of a germ tube) were the most virulent and were capable of killing 100% of larvae after 5 or 24 h when 1 × 107 or 1 × 106 conidia, that had been allowed to germinate for 24 h, were used. Examination of the response of insect haemocytes to conidia at different stages of the germination process established that haemocytes could engulf non-germinating conidia and those in the early stages of the germination process but that conidia, which had reached the outgrowth stages of germination were not phagocytosed. The results presented here indicate that haemocytes of G. mellonella are capable of phagocytosing A. fumigatus conidia less than 3.0 μm in diameter but that conidia greater than this are too large to be engulfed. The virulence of A. fumigatus in G. mellonella larvae can be ascertained within 60–90 h if infection densities of 1 × 106 or 1 × 107 activated conidia (pre-incubated for 2–3 h) per insect are employed.

    Item Type: Article
    Keywords: Aspergillus fumigatus - Galleria mellonella - insect haemocytes - pathogenicity - virulence
    Academic Unit: Faculty of Science and Engineering > Biology
    Item ID: 906
    Depositing User: Dr. Kevin Kavanagh
    Date Deposited: 21 Feb 2008
    Journal or Publication Title: Mycopathologia
    Publisher: Springer
    Refereed: Yes
    URI:
    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

    Repository Staff Only(login required)

    View Item Item control page

    Downloads

    Downloads per month over past year

    Origin of downloads