0:00
Hi.
I'm Katja Hanack,
Professor of Immunotechnology at the
University of Potsdam in Germany.
Today, I'm going to talk about
In Vivo Antibody Discovery,
especially about
Hybridoma technology
to generate monoclonal
antibodies in vitro.
0:17
To give a short summary
about the content.
First of all, I will talk
about the in vivo process,
how antibodies are induced
in a mammalian system
and in the main
part of the talk,
I will focus on the
technology aspects to induce
specific immune
responses and how to
select feasible binders
for several applications.
0:41
On this slide, you can
see an overview of
how antibody generation
is induced in mammalians.
In vivo, antibody generation
process starts with
the entry of a pathogen
or a foreign substance,
and this entry is recognised
by specialised immune cells,
such as macrophages
or dendritic cells.
You see an
antigen-presenting cell.
These cells are the sentinels
of the immune system.
They are also called
dendritic cells
because of their morphology.
They have long
dendrite by which they
can screen their
environment for antigens.
The cell surface is covered
by specialised receptors,
so-called pattern
recognition receptors,
and a famous subgroup is
the Toll-like receptors.
With those receptors,
they are recognising
pathogenic structures,
such as lipopolysaccharides
on bacterial surfaces.
Once they have recognised
such a structure,
they start to internalise
the whole pathogen and
and degrade it intracellularly
in a so-called phagolysosome.
In this compartment, we have
two different situations.
The first one is a
very low pH of two,
which is degrading
pathogenic proteins
The second is the appearance of
specific enzymes like cathepsin,
which help to cleave the
protein fragments into
smaller peptides (8
to 12 amino acids).
These small fragments are loaded
on MHC class II complexes
and transported to
the cell surface.
With this process,
the dendritic cell is able to
present antigens to T cells,
and this greenish
cell is a T cell,
and this T cell has a
counterpart receptor,
the T cell receptor, by
which they can recognise
the presented peptide
fragment on the MHC complex.
This is a speciality of
the T cell receptor.
The receptor has a
dual recognition,
it recognises the
body's own MHC complex,
together with the
foreign peptide fragment
which is presented by
the dendritic cell.
This recognition is necessary
to activate the T cell
and together with other
co-stimulatory signals from
a co-receptor and
different cytokines,
the T cell differentiates
into an active state.
When we have a look at the
induction of antibody responses,
we need a T helper cell type.
This T helper cell type
helps the B cell in terms of
activation and induction of
specific antibody responses.
