| Authors: |
Boran Altincicek
and Monica Linder
and Dietmar Linder
and Klaus T. Preissner
and Andreas Vilcinskas
|
| Tags: |
IFZ
imported
|
| Abstract: |
Thermolysin-like metalloproteinases such as aureolysin, pseudolysin,
and bacillolysin represent virulence factors of diverse bacterial
pathogens. Recently, we discovered that injection of thermolysin into
larvae of the greater wax moth, Galleria mellonella, mediated strong
immune responses. Thermolysin-mediated proteolysis of hemolymph
proteins yielded a variety of small-sized (< 3 kDa) protein fragments
(protfrags) that are potent elicitors of innate immune responses. In
this study, we report the activation of a serine proteinase cascade by
thermolysin, as described for bacterial lipopolysaccharides (LPS), that
results in subsequent prophenoloxidase activation leading to
melanization, an elementary immune defense reaction of insects.
Quantitative real-time reverse transcription-PCR analyses of the
expression of immune-related genes encoding the inducible
metalloproteinase inhibitor, gallerimycin, and lysozyme demonstrated
increased transcriptional rates after challenge with purified protfrags
similar to rates after challenge with LPS. Additionally, we determined
the induction of a similar spectrum of immune-responsive proteins that
were secreted into the hemolymph by using comparative proteomic
analyses of hemolymph proteins from untreated larvae and from larvae
that were challenged with either protfrags or LPS. Since G. mellonella
was recently established as a valuable pathogenicity model for
Cryptococcus neoformans infection, the present results add to our
understanding of the mechanisms of immune responses in G. mellonella.
The obtained results support the proposed danger model, which suggests
that the immune system senses endogenous alarm signals during infection
besides recognition of microbial pattern molecules. |
@article{ISI:000243230500018,
title = {Microbial metalloproteinases mediate sensing of invading pathogens and activate innate immune responses in the lepidopteran model host Galleria mellonella},
author = {Boran Altincicek and Monica Linder and Dietmar Linder and Klaus T. Preissner and Andreas Vilcinskas},
journal = {INFECTION AND IMMUNITY},
number = {1},
pages = {175-183},
volume = {75},
year = {2007},
abstract = {Thermolysin-like metalloproteinases such as aureolysin, pseudolysin,
and bacillolysin represent virulence factors of diverse bacterial
pathogens. Recently, we discovered that injection of thermolysin into
larvae of the greater wax moth, Galleria mellonella, mediated strong
immune responses. Thermolysin-mediated proteolysis of hemolymph
proteins yielded a variety of small-sized (< 3 kDa) protein fragments
(protfrags) that are potent elicitors of innate immune responses. In
this study, we report the activation of a serine proteinase cascade by
thermolysin, as described for bacterial lipopolysaccharides (LPS), that
results in subsequent prophenoloxidase activation leading to
melanization, an elementary immune defense reaction of insects.
Quantitative real-time reverse transcription-PCR analyses of the
expression of immune-related genes encoding the inducible
metalloproteinase inhibitor, gallerimycin, and lysozyme demonstrated
increased transcriptional rates after challenge with purified protfrags
similar to rates after challenge with LPS. Additionally, we determined
the induction of a similar spectrum of immune-responsive proteins that
were secreted into the hemolymph by using comparative proteomic
analyses of hemolymph proteins from untreated larvae and from larvae
that were challenged with either protfrags or LPS. Since G. mellonella
was recently established as a valuable pathogenicity model for
Cryptococcus neoformans infection, the present results add to our
understanding of the mechanisms of immune responses in G. mellonella.
The obtained results support the proposed danger model, which suggests
that the immune system senses endogenous alarm signals during infection
besides recognition of microbial pattern molecules.},
issn = {0019-9567},
keywords = {IFZ imported }
}
::