The greater wax mothGalleria mellonella: biology and use in immune studies

Abstract

The greater wax moth Galleria mellonella is an invertebrate, which is increasingly being used in scientific research. Its ease of reproduction, numerous offspring, short development cycle, and, finally, its known genome and immune-related transcriptome provide a convenient research model for investigation of insect immunity at the biochemical and molecular levels. Galleria immunity, consisting of only innate mechanisms, shows adaptive plasticity, which has recently become the subject of intensive scientific research. This insect serves as a mini host in studies of the pathogenicity of microorganisms and in vivo tests of the effectiveness of single virulence factors as well as new antimicrobial compounds. Certainly, the Galleria mellonella species deserves our attention and appreciation for its contribution to the development of research on innate immune mechanisms. In this review article, we describe the biology of the greater wax moth, summarize the main advantages of using it as a model organism, and present some main techniques facilitating work with this animal.

RNase R, a new virulence determinant ofStreptococcus pneumoniae

“…To test this, larvae were infected with this bacterium and the gene expression of four selected antimicrobial peptides was monitored at 1, 6, 12 and 18 h postinfection. The selected genes coded for the cysteine-rich antifungal peptide gallerimycin [26], a defensin called galliomycin [13], lysozyme [26], and an inducible metalloproteinase inhibitor (IMPI) [26]. Gene expression was determined by quantitative RT-PCR analysis of the total RNA extracted for each postinfection time point.…”

“…The Toll pathway, a crucial signalling cascade of the insect innate immune system, is activated by fungi and Gram positive bacteria leading to the synthesis of antimicrobial peptides [13, 32]. G. mellonella contains a notable antimicrobial peptide arsenal that is released into the hemolymph, where it attacks elements of the bacterial or fungal cell wall [21].…”

“…To overcome these limitations, alternative infection model organisms have been investigated, such as the larvae of the wax moth Galleria mellonella . G. mellonella larvae have been proven to be an effective model host for infection studies in several microorganisms ([9-12] reviewed by [13]) including S. pneumoniae [14]. Additionally, larvae can be reared at temperatures ranging from 20°C to 30°C and the infection studies can be conducted between 15°C to above 37°C, which enables experiments that attempt to mimic a human environment [15, 16].…”

“…The humoral response is composed by soluble effector molecules which immobilize and/or kill the pathogen when released into the hemolymph. This response include the induced expression of antimicrobial peptides, as well as several plasma proteins that serve as opsonins, complement-like proteins, and release of the phenol oxidase system that culminates in the synthesis of the dark pigment melanin [21–23] reviewed by [13]).…”

Transcriptomic Insights into the Insect Immune Response to Nematode Infection

“…Insect host defenses include hemocyte-related functions and the production of antimicrobial peptides and other effector molecules, which are secreted into the hemolymph [ 4 , 5 , 6 ]. Understanding immune reactions in insects has been facilitated by the use of insect models that permit elegant genetic manipulations in the laboratory, but significant discoveries have also been made in insects of agricultural or medical importance [ 7 , 8 , 9 , 10 ].…”