0:00
Hello and welcome to
this presentation.
My name is George Holländer.
I am a professor at the University
of Oxford in the United Kingdom,
with affiliations to the ETH Zürich and the
University of Basel, both in Switzerland.
We are talking today about
the thymus and T
cell development,
and the presentation is a
primer into this topic.
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The thymus is the
primary T lymphoid organ
and sits in the chest cavity
in front of the heart.
It's anatomical location is
between the two pulmonary lobes.
If analysed by histology,
it will reveal a
lobulated structure
where each of the lobules has
a cell dense outer cortex and
a central medulla
that appears to
be less packed with
lymphoid cells.
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What is the overall
function of the thymus?
The thymus is similar to an
Institute of Higher Education.
Where precursor cells -
shown as the students -
enter the institute
or the university.
After a while, they will successfully
exit as fully trained individuals.
During their time
at the university,
they are being taught to achieve
certain functional capacities.
The teachers - shown as the
individuals with the yellow coats -
have a particular task for
the students to achieve.
Namely the creation of a
graduation cap that fulfils
certain criteria.
In biological terms,
the students are the
developing T cells,
and the graduation cap is
a T-cell antigen receptor
that conforms to certain
qualitative criteria.
Now, as you can see some of the
students are well on their way
and have chosen mortars that don't conform
to the overall expectation of the square.
Now, in particular,
there is a student
in the middle that is being told
off by the teacher and
sent away in shame.
What happens to this example,
but obviously not in real life,
is this student will await
a very drastic outcome
and will eventually be
deleted from the classroom.
This is really the fate of most of the T
cells that are being educated in the thymus.
The overall goal of
the immune system is
