0:00
Hi. My name is Thomas Areschoug.
I'm working at the Division
of Medical Microbiology
at Lund University in Sweden.
I will give you a lecture on how
bacterial pathogens
avoid phagocyte killing.
0:15
Bacterial evasion of
phagocyte killing
is an important step in
the pathogenesis of
bacterial disease.
Today, numerous
bacterial mechanisms to
avoid phagocyte killing
have been described
in the literature.
These studies are not
only important for
our understanding of
the molecular pathogenesis
of bacterial disease,
but they may also
reveal which parts of
the host's immune system
are of importance
for host protection
against bacteria.
0:43
The aim of my presentation
is to, first,
give you a brief background
on phagocytic cells.
We'll focus on the macrophages
and the neutrophils.
We will then go through
the different types of
phagocytosis and phagocytic
killing mechanisms.
Finally, I will give
you a few examples of
bacterial mechanisms to evade
phagocytosis and
phagocytic killing,
including both
classical examples
and a few novel mechanisms
described more recently.
1:14
All macrophages
stem from a common
myeloid progenitor cell
in the bone marrow,
which migrates into the blood
and develops into monocytes.
The monocytes then migrate into
various types of
tissues in the body
and differentiate into
resident macrophages
with a distinct phenotype
dependent on the
tissue location.
In the skin, for example,
you find the Langerhans cells,
Kupffer cells in the liver,
osteoclasts in the bone,
and microglia in the
central nervous system.
In the tissues, you can also see
more recently recruited
macrophages that have
been activated by
various stimuli.
