"Studies involving microgravity suggest stem cells will grow faster in space"

Interview mit Abba Zubair, M.D., Ph.D. von der Mayo Clinic Jacksonville, Florida (USA)

The International Space Station ISS is not only the largest artificial object in space. It is also a laboratory for physicists, chemists, biologists and physicians and orbits earth at 28.000 kilometers per hour at an altitude of 400 kilometers. Thanks to this location, the ISS could one day make an important contribution to regenerative medicine.


Photo: Abba Zubair

Abba Zubair, M.D., Ph.D.; © Mayo Clinic

MEDICA.de talked to Abba C. Zubair, M.D., Ph.D., from the Mayo Clinic Jacksonville, Florida (USA). In a current research project he wants to cultivate human stem cells in a bio reactor at the ISS. These cells could grow significantly faster in microgravity than on earth and open new perspectives in the treatment of tissue damage.

MEDICA.de: Dr. Zubair, you recently received a Center for the Advancement of Science in Space (CASIS) grant to research the cultivation of human stem cells in space. Where does the idea for this project originally come from?

Abba Zubair: The alignments of multiple factors led to the idea of growing stem cells in space. First, it was my childhood dream to study astronomy and be in space. However, having grown up in Africa Nigeria, my career advisors steered me away from that idea. So I ended up going to medical school and pursuing a career in transfusion medicine and stem cell therapy. Then I met Larry Harvey, a space enthusiast, who suggested we should study cancer cells in space. I then steered us towards stem cells because that has been my area of clinical practice and research, and above all, there is a clinical need to find methods to efficiently grow stem cells for regenerative medicine applications.

MEDICA.de: What kind of stem cells will be cultivated in the experiment?

Zubair: For the CASIS award, we are primarily studying mesenchymal stem cells (MSC). However, as a backup we will also grow induced pluripotent stem cells (iPSC).

MEDICA.de: What are their potential medical uses?

Zubair: Their potential medical uses are endless. MSC have been shown to secrete factors that stimulate tissue repair and cell regeneration. In addition, they are capable of controlling inflammation. They have been shown to have the capacity to induce heart, kidney, joint, and brain repair and regeneration. For this award, we intend to assess the safety of using space grown MSC to treat patients with stroke. I am very passionate about stroke because it is the condition that killed my mother. Knowing how painful this is, I want to find an effective treatment for this condition so that no son will experience the agony of losing his mother because of stroke. MSC are also capable of preventing organ rejection and treating many inflammatory diseases.

IPSC behave like embryonic stem cells and they can give rise to all tissues in the body. It is only now that we have begun to understand their capabilities.
Graphic: Space station

The ISS is a flying research laboratory in space. The near-zero gravity could speed up the cultivation of stem cells (symbol picture); © panthermedia.net/Norbert Dr. Lange

MEDICA.de: Why is it difficult to cultivate these cells here on earth?

Zubair: Stem cells inherently control their numbers. As the seed responsible for developing and maintaining every organ, their numbers need to be kept in check for proper development. Too many stem cells in the body may result in growth abnormalities and possibly cancer. Typically, when stem cells are stimulated with growth factors they usually differentiate to their progenies while still maintaining their numbers. For example, when a person bleeds the body responds by stimulating blood stem cells to make more blood cells while still maintaining the same number of blood stem cells in the body.

MEDICA.de: How is space going to change this?

Zubair: The near zero gravity in space, we believe, affects the biology of stem cells. We know gravity affects all aspects of life on earth, from cell division to cell-cell interactions to tissue and organ development. Already, studies involving simulated microgravity on earth suggest stem cells will grow faster in space. Our study is designed to prove this observation using a true microgravity environment in space.

MEDICA.de: Regarding the bioreactor to cultivate the cells, is there something special about design and construction – since it will be send to space?

Zubair: Yes, every aspect of the bioreactor has to be designed for space use. Since liquids do not easily pour from one container into another in space, simple tasks for cell culture such as media exchange have to be engineered. Therefore, we will be using BioCell, a semi-automated cell culture system developed by BioServe. The BioCell system has already been tested in space research and will be customized for our research needs.

MEDICA.de: Whom are you working with to design it? What is the expertise of the engineers involved?

Zubair: We are working with BioServe, a subsidiary of University of Colorado, with over 30 years of experience in supporting space research.
Graphic: Flight of a SpaceShuttle

"The technology is available": With sufficient public support and funding patients on Earth could be treated with cells, tissue and even organs from the ISS, says Dr. Zubair; © panthermedia.net/3DSculptor

MEDICA.de: Does the crew of the ISS conduct the experiment, i.e. do they require certain training, or will the process be automated?

Zubair: Our experimental design is mostly automated, but crew training and time will be needed to activate experiments, take cell images as they grow, and collect cell samples for return to earth.

MEDICA.de: How long will the experiment at the ISS take?

Zubair: Our experiments at the ISS will be performed in the period of one month. However, the total study time from pre-flight preparation to cell analysis post flight will take about two years.

MEDICA.de: How would you ideally like to continue this work afterwards?

Zubair: The study is designed to be conducted in three phases. This is the first phase in which we hope to answer the basic question whether MSC and iPSC can grow better in space and whether the cells grown in space are safe to be used in humans.

Once we can positively answer these questions with confidence, the next phase is to go back to space and grow enough stem cells to support a pilot clinical trial in patients with recent hemorrhagic stroke. We have already shown that earth grown MSC can induce neuro-regeneration and control inflammation in a stroke model. We are currently in the process of starting a pilot clinical trial using earth grown MSC for treatment of this condition. We hope this clinical trial will be a template for conducting the same trial using space grown MSC.

In the next phase of the study, we hope to explore the production of large scale stem cells, tissue, and possibly organs at the ISS for human application. We know this is many years in the future, but we believe all this is possible because the technology to do this is available. All we need is public support and funding to achieve our objectives.
Photo: Timo Roth; Copyright: B. Frommann

© B. Frommann

The interview was conducted by Timo Roth.