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| Role of Interleukin-2 Receptor in
Signal Transduction and Gravisensing Threshold of T-Lymphocytes (Leukin) |
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Experiment/Payload
Overview |
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Brief Summary
Leukin will study the signal transduction pathway of the activation
of T-lymphocytes. This investigation will also determine if loss of
Interleukin-2 receptor expression is the cause of inhibition. Microgravity
will be used as an inhibitor of activation.
Principal Investigator
• Isabelle Walther, Ph.D., Swiss Federal Institute of Technology,
Space Biology, Zurich Switzerland
Co-Investigator(s)/Collaborator(s)
Augusto Cogoli, Ph.D., Swiss Federal Institute of Technology, Space
Biology, Zurich Switzerland
Millie Hughes-Fulford, Ph.D., University of California - San Francisco,
San Francisco, CA
Proto Pippia, Ph.D., University of Sassari, Sassari, Italy
Payload Developer
Swiss Federal Institute of Technology, Space Biology, Zurich Switzerland
Sponsoring Agency
European Space Agency (ESA)
Expeditions Assigned
14
Previous ISS Missions
A previous Leukin investigation was flown on STS-107 (Columbia)
in 2003. This investigation will fly again for ESA on Expedition
14.
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Experiment/Payload Description |
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Research Summary
• Leukin will help investigators understand why single cells
are sensitive to microgravity and to study the microgravity effect
on the immune system cells.
• The results of Leukin will enable understanding of
the cause of reduced immune function associated with spaceflight
so crew members stationed on the Moon or on a Mars mission will
remain healthy.
Description
The International Space Station provides a modern platform to study
physiology and molecular changes in space. In addition, understanding
these physiological changes provides knowledge that we can apply
to common diseases found in the general population. The results
also help us to understand microgravity-induced immunosuppression.
Early NASA studies demonstrated that the lymphocytes (white blood
cells) had a decreased response to mitogen stimulation of growth.
In the late 60?s returning Apollo astronauts were found to have
reduced immune function after spaceflight, taking approximately
7 days to recover normal function. Astronauts exposed to microgravity
did not respond to mitogen, a protein that encourages cell division,
while cells belonging to non-flown astronaut backups had normal
response.
The aim of Leukin is to study the signals which cause the activation
of T-lymphocytes, white blood cells that play a central role in
cell-mediated immunity. The focus is on the role of Interleukin-2
(IL-2), a hormone that stimulates the growth of T-lymphocytes and
plays an instrumental role in the body?s response to pathogens (bacteria,
viruses, fungi, etc.) and in the determination of its genetic expression
(process by which a gene's DNA sequence is converted into the structures
and functions of a cell).
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Applications |
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Space Applications
Leukin may help scientists to better understand the depression
of the immune system which occurs during spaceflight and, therefore,
to devise more adequate preventive or corrective measures for crew
members during long duration missions.
Earth Applications
Determining the factors which cause IL-2 suppression can help scientists
on Earth better treat immunosuppressed patients.
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Operations |
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Operational Requirements
Cells will be prepared at the launch site just prior to launch
from fresh human blood. The purified T-lymphocytes will be loaded
into experiment containers just prior to launch. Following arrival
on ISS, fixative will be added to a specified group of the cells.
Fixative will be added to another group of cells 30 minutes following
arrival on ISS and to a third group 4 hours after arrival on ISS.
Operational Protocols
The T-lymphocytes will be purified and sealed in experiment containers
shortly before launch. Once on orbit an astronaut will inject an
activator. After intervals of 0 minutes, 30 minutes and 4 hours
the cultures will be fixed, by injection of a preservation solution,
frozen and returned to the investigators for analysis.
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Related Web Sites |
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• The information provided is courtesy of the ESA Astrolab Mission
web page.
• Space Biology Group
• The Lab of Cell Growth - University of California Medical School,
San Fancisco, CA
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Images |
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Cell culture cassette system showing
multi-injector unit used for spaceflight experiment. Image courtesy
of NASA.
+ View Larger Image |
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