Cytocentric Visionaries: Roger Rönn

This is a five-part series of blog posts containing excerpts from an interview that Dr. Alicia Henn, Chief Scientific Officer of BioSpherix, conducted with Roger Rönn, who is finishing his PhD at Lund University. Our conversation was edited for brevity and clarity.

In the last post, Roger told us about factors that might make researchers hesitate to control oxygen levels for their cells. Today, we discuss the importance of low oxygen levels for HSC cells.

We’ve been talking with researchers to get a sense of what terminology might be emerging with a new awareness of the importance of physiologic oxygen studies.What kind of words do we need to really describe what’s going on?

RR: Most people culture their cells at 21% O₂, atmospheric oxygen tension, the same concentration that we breathe. This is also referred to as normoxia. This is something that has bugged me for some time; there is nothing normal with what we call normoxia.

We need to take a step back and look around for the simplest questions. What is normal and what is not? What is physiological? Oxygen tension is such a fundamental thing that we easily forget to think about it. I think there are great potential gains if we allow ourselves to reconsider these questions.

Would you call it physioxia? Does that get close enough to what is going on?

RR: The question is, if you really want to go to the level that is truly physiological for a functional HSC? Hematopoietic stem cells are slumbering, they are quiescent, and many of them are only called upon to divide when there is a serious situation. These cells are very sensitive and they need to be protected. That’s why they are hiding out in the bone marrow, in a highly protective niche that’s also low in oxygen.

If you want to work with HSCs for therapeutic purposes you need the cells to expand. But that’s not something they do in their typical adult physiological condition either. So you want them to grow, while protecting them from the damage that comes with it.

Also, proteins and chemicals have a half life. They will degrade not just because they are used up by cells, but also because of the used conditions. So you can potentially have benefits at many different levels if you just take down the background reactivity that comes with a high O₂ level. Your chemicals might have a longer half life, and your cells experience less stressful insult, and possible mutation, that otherwise occurs at atmospheric O₂ levels.

In the next post, Roger tells us about the toughest part of carrying out low-oxygen experiments.

If you would like you and your work to be featured in the Cytocentric Visionary series, please contact us and tell us how your work fits the Cytocentric Principles.

 Roger Rönn interview: Part 1, Part 2, Part 3, Part 4, Part 5