Transcript Transplantation

Transplantation
and its use in gene technology
by Christopher Schlemm and Ilja Klebanov
Structure
1. Introduction
2. General information
3. Methods of
transplantation:
3.1 Autografting
3.2 Allografting
3.3 Xenografting
4. Problems of
transplantation
5. Gene technology as a
solution
5.1 Organ breeding
5.2 Suppression of
rejection
5.3 Ideas for the future
6. Conclusion
General information
Definition: to transfer a graft (an organ or tissue) from
one part or individual to another
May take place between:

different parts of the same
organism (autografting)
 different organisms of the
same species (allografting)
 different species
(xenografting)
General information:
Immune system rejection
Often a transplanted organ is not identified
by the immune system as the tissue of the
organism
 It can be attacked and destroyed.
Against this effect the patient has to swallow
Immunesuppressiva which cause symptoms
like suffering from AIDS.
In 15-20 minutes the organ dies, unable to
withstand the immune system attack.
Rejection
of a heart
Methods of Transplantation:
Autografting
•
•
•
The transfer of self tissue from
one body site to another in the
same individual
Due to the genetic homology of
the tissue, the immune system
does not respond to it
Use: synthetic implantation
skin grafts
 bone marrow transplantation
 hair

Methods of Transplantation:
Allografting
Definition: The transfer of organs or
tissue from human to human
or from cadaver to human
•
•
As there are more and more people
every year waiting for donor organs and
tissues, allografting transplantation has
become quite common.
Allografting transplantation has many
applications.
Allografting:
Applications of allografting transplantation
Allografting:
The importance of transplantation:
Methods of Transplantation:
Xenografting
Definition: Xenotransplantation – the
transfer of tissue from one
species to another
Usually refers to the implantation of
animal tissue in humans
provides a new source of organs for
humans
 many different types of tissue can be
transplanted:
e.g. heart, kidney, liver or lung

Xenotransplantation:
From which animals are we able to
transplant organs
1. The Chimpanzee:
Its DNA sequence
differs from ours by
only 2%
2. The Baboon:
Its organs are too
small for a large
adult human
3. The Pig:
Surprisingly similar too
our anatomy and
physiology
Problems of Transplantation
• There are not enough organs
At least 150,000 patients in industrially developed
countries badly need donor organs and tissues
Every 14 minutes another name is added to the
national transplant waiting list.
About 16 people die because of the lack of
available organs for transplant each day.
• Rejection:
When the immune system of the host detects
foreign graft tissue, it launches an attack, resulting
in tissue rejection
Gene technology as a solution
What is possible using gene technology refering to
the problems?
Gene technology offers the possibility to breed the
desired organs in animals.
Lack of organs is no longer a problem
Gene technology makes it possible to humanize
the bred organs - the immune system identifies the
organ as its own tissue.
Immune system rejection is prevented
Gene technology as a solution:
Gene technology - transgenic animals
Organ breeding:
•A transgenic animal carries a foreign gene that
has been inserted into its genome.
•The transgenic animal shows the specific
characteristics which are coded on the inserted
gene
 A gene which is responsible for the
construction of a human organ makes the
organism produce the organ additionally.
Gene technology as a solution:
The insert of a foreign gene into an animal
I. DNA microinjection
The DNA is inserted into the cell
with a small syringe
II. Retrovirus gene transfer
The DNA is carried into a cell by a virus.
The virus carries the desired DNA and
infects the cell, which has the effect that
the DNA is built into the cell‘s DNA.
Gene technology as a solution:
Suppression of immune system rejection
The immune system has the task to protect
the organism against every foreign cell.
The immune system distinguishes between
cells of the body and foreign cells.
The genes which are responsible for the own
tissue not being rejected can be injected into Not rejected
an animal embryo the organs of which are
pancreas
then similar to the ones of the human.
It is possible to humanize the bred organs by making
certain genetic modifications.
Then the organs are accepted by the immune system.
Gene technology as a solution:
Ideas for the future
Organ breeding by using stem cells:
•Stem cells are able to become any cell which is found in the
human. Under specific conditions stem cells could become cells of
a kidney, a brain and so on.
•Thus by using one stem cell from an embryo a whole new organ
could be created.
Embryo
Stem cell
Cell differentiation
Conclusion
• During the era of gene technology transplantation
has improved very much
• In future donors won‘t be needed any longer
• Scientists will be able to breed organs and to adapt
them to the organism of the patient
• Most of the ethnical problems will be eliminated