Immune suppression of Galleria mellonella (Insecta, Lepidoptera) humoral defenses induced by Steinernema feltiae (Nematoda, Rhabditida): involvement of the parasite cuticle.
Immune depression of Galleria mellonella larvae was evaluated a short time after infection with the entomopathogenic nematode Steinernema feltiae. In the host the activity of the enzymatic cascade known as the proPO system was significantly reduced by the presence of either live or dead parasites. The presence of parasites decreased the LPS-elicited proPO system activity. In addition, this process seems to be related to a decrease in the activity of hemolymph proteases, more than to phenoloxidase damage. proPO inhibition was also achieved by injected isolated cuticle fragments, suggesting that the parasite body surface plays an important role in the early parasitation phase.
Brivio
Maurizio F
MF
Department of Structural and Functional Biology, University of Insubria, via J.H. Dunant 3, Varese, Italy. maurizio.brivio@uninsubria.it
Pagani
Manuela
M
Restelli
Stefano
S
D000818:Animals; D010450:Endopeptidases / Q000378:metabolism; D006458:Hemolymph / Q000201:enzymology / Q000469:parasitology; D006790:Host-Parasite Interactions; D007814:Larva / Q000276:immunology; D009036:Moths / Q000276:immunology*; D010572:Pest Control, Biological; D017168:Rhabditida / Q000502:physiology* / Q000648:ultrastructure
D010450:Endopeptidases