Leukin-2 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(s)
Swiss Federal Institute of Technology, Space Biology, Zurich, , Switzerland
European Space Agency (ESA)Sponsoring Organization
Information PendingResearch Benefits
Information PendingISS Expedition Duration
September 2006 - April 2007Expeditions Assigned
14Previous ISS Missions
A previous Leukin investigation was flown on STS-107 (Columbia) in 2003. This investigation will fly again for ESA on Expedition 14.
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-2 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).
Leukin-2 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.
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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