0:00
Hello
My name is Dominique Ferrandon.
I've been working on
Drosophila innate immunity
in Strasbourg for
more than 15 years.
Today, I'm going to present how Drosophila are used
to model intestinal infections
and shows that, thanks
to its advanced genetics, it
provides a powerful paradigm
to understand the different
facets of mucous host defenses.
0:24
The first question
to address is- why
one should use Drosophila
to study innate immunity?
Many fly stocks can be raised
at relatively low cost.
Also Drosophila has a short life cycle
and produces an abundant offspring.
As will be illustrated in
this talk, its main strength,
however, lies in its genetics,
especially the ability
to perform genome-wide
screens in a living animal.
As regards immunity, flies like
a conventional adaptive immunity.
And first, it is easier to
correlate the effect of mutations
in immunity genes to a phenotype of
susceptibility to a given pathogen.
1:01
This slide shows that we share with
Drosophila a common ancestor that
lived more than three-quarters
of a billion years ago.
One should note the
acquisition of the machinery
to generate somatic recombinant immunoreceptors in gnathosomes.
And first, you must
extend vertebrates
some 450 million years ago.
Thus, given this long
period of evolution,
is it meaningful to study
the anatomy of insects
to understand our own immune system?
1:28
The answer to this question
is illustrated in this slide.
This common Metazoan
ancestor evolved
in a world that was already
dominated by microbes.
Thus, evolution had already selected
a primeval immune system from which
both the protostomian and the
deuterostomian immune systems
are derived.
Even though they may not
share the same molecules,
many of the primordial
principles have been conserved
throughout evolution, and therefore
results obtained in the Drosophila
model system may guide
investigations in mammalian models.
This concept is especially
well-illustrated by the study
of the Drosophila
systemic immune response
presented in the next slide.