Cell Biology - Reading Task (Low Demand age 12)
Astronauts growing new organs on International Space
Station - Process that leads three-dimensional cultures to form in lowgravity is still not understood.
March 2020
Astronauts are growing the beginnings of new organs on board the International Space
Station. The experiment is an attempt to grow human tissue by sending adult human
stem cells into space, and allowing them to grow there.
The idea is that the stem cells will develop into bone, cartilage and other organs. If that
is successful, the discoveries could be used to try and grow organs for transplant.
The experiment uses “weightlessness as a tool”, according to one of the two researchers
who are conducting the research. The lack of gravity on board the International Space
Station will be used to encourage the stem cells to grow into tissue in three dimensions.
This is different to the single-layer structures that they usual grow into on Earth.
It is being conducted by the astronauts on board the International Space Station. They
are using a “mobile mini-laboratory”. The experiment will last for a month. During this
time scientists will watch to see how the stem cells grow.
If it is successful, they hope to switch from a small laboratory to bigger production.
From there, they could use the process to generate tissue for transplants. They will do
this by taking cells from patients or generating organ-like material that could be used to
test drugs. This is to make sure that it works for specific patients. Also, it will reduce the
number of animals used in experiments.
On Earth, tissue grows in “monolayer” cultures. This means that they grow in flat, 2D
tissue. But investigations both in space and Earth suggest that in microgravity, “cells
exhibit spatially unrestricted growth”. This means that they grow into complex 3D
shapes,” said Oliver Ullrich, who is also leading the research.
Previous research has involved simulated and real experiments. Scientists have used
tumour cells and placed real human stem cells into microgravity simulators. The next
stage of the research “there is no alternative to the ISS” because 3D tissue formation of
this kind requires several days or even weeks in microgravity.
After the month-long experiment, the scientists will get the samples back and expect to
see successful formation of “organoids”. These are smaller, more simple versions of
organs grown inside the test tubes. “The test tubes were launched with stem cells and
are expected to return to Earth with organ-like tissue structures inside,” said Professor
Ullrich.
Scientists are still not sure why the conditions of the International Space Station lead to
the assembly of complex 3D tissue structures. Scientists are continuing to research how
the gravitational force and the “molecular machinery in the cell” interact to create new
and different kinds of tissue on Earth and in space.
Figure 1. Number of ongoing, new and completed stem cell clinical trials in the UK from
2013-2019.
Use the information in the news article and the graph above to answer the following
questions in as much detail as possible.
1. What is the specific idea behind conducting the stem cell research and experiments on
the International Space Station (ISS)? (1)
2. What specifically is being used as a tool in this research being undertaken on the ISS?
(1).
3. What is the proposed purpose of the detailed research, if it is successful, in the small
laboratory on the space station? (1)
4. Explain the use of the term ‘organoids’ in the news extract and detail where these are
grown. (2)
5. Describe a trend in the graph above in relation to ongoing stem cell clinical trials. (1)
6. Explain any trend or pattern which can be seen in relation to new trials being
conducted into stem cell research. (2)
7. Describe the suspended or withdrawn trial data on the graph and offer an explanation
as to why they may have been withdrawn. (3)
8. Using your knowledge of stem cells explain their importance. Highlight any ethical
considerations raised in relation to the use of stem cells. Use data from the graph to
support your answer where relevant. (4)