Little is known about the effects of deep space radiation on hematopoietic stem cells. Hematopoietic stem cells give rise to both the blood and immune systems, and damage to these cells from space’s environment could have grave immediate and long-term consequences. The goal of Dr. Alan M. Gewirtz’s research is to identify and quantify the risks of deep space radiation to the hematopoietic stem cells and explore potential countermeasures to negate the cellular and molecular damage.
Overview
Effect of Deep-Space Radiation on Human Hematopoietic Stem Cells
Principal Investigator:
Alan M. Gewirtz, M.D.
Organization:
University of Pennsylvania School of Medicine
Technical Summary
Astronauts on long-term missions in deep space will be placed at risk from a variety of hazards. Some of these are known while others may be anticipated. Damage to hematopoietic stem cells as a result of radiation exposure is as an example of the latter. Our long-term goal is to identify and quantitate the risks of deep-space radiation to the human hematopoietic system, with particular emphasis on the hematopoietic stem cell.
Stem cells are the ultimate source of both the blood and immune systems, and damage to these cells could have grave immediate and long-term consequences. At the same time, because these cells can be readily removed from the body, manipulated and stored, they are also unique candidates for countermeasures that might obviate, or totally negate, damage incurred to them. Accordingly, this project will have three specific aims which support our long-term goal and these are to:
- Investigate the cellular consequences of exposing human hematopoietic stem (HSC)and progenitor (HPC)cells to an environment which simulates the radiation environment of deep space;
- Examine the molecular consequences of exposing human hematopoietic stem cells to an environment which simulates the radiation environment of deep space. This aim has two purposes. If radiation leads to degradation of hematopoietic cell function it will clearly be of interest to look for the molecular lesions potentially responsible for such damage. Alternatively, more long term, but initially occult damage may also be induced. The consequences of such damage could lead either to a complete failure of hematopoiesis (aplastic anemia) or the development of hematologic malignancies. Identification of such damage is therefore important, and;
- Design potential countermeasures to obviate or negate cellular and molecular damage discerned during the course of carrying out Aims 1 and 2.
We expect both simple and more complex solutions to problems that might be identified during the course of this study. We suggest that prophylactic (pre-flight) harvest and storage of astronaut stem cells might be a safe, effective and relatively inexpensive mechanism for countering long-term damage to cells of the hematopoietic systems. Countermeasures, which might prove effective in combating damage encountered during flight, will also be developed and explored for their utility.
Earth Applications
The development of effective radiation countermeasures could have significant impact on Earth for civilians and military personnel alike. With regard to the civilian population, it is quite conceivable that results we obtain will be relevant to patients undergoing cancer chemotherapy and radiation therapy. In this regard, it is possible that our studies will provide reagents and strategies for helping to protect normal tissues from the collateral damage of anticancer treatments. It is also possible that results we generate will be relevant to radiation workers and members of the armed forces who may be exposed to radiation during the course of carrying-out their respective duties.
This project's funding ended in 2004