Dr. Doris Taylor

Stem Cell Mediated Organ Regeneration

Taylor. 2009. From stem cells and cadaveric matrix to engineered organs. Current Opinion in Biotechnology. 20:598-605.

Main Research Article: Ott et al., and Taylor. 2008. Perfusion-deceullularized matrix: using nature’s platform to engineer a bioartificial heart. Nature Medicine. 14:2. 213-221.

Rooke. 2010 A closer look at Stem cell treatments: an ISSCR initiative.

Question 1

Dr. Taylor can you please tell us a bit about yourself, your career path over the years and how it has led to your work on stem cell based organ regeneration?  And to set the stage for today’s discussion, can you describe concisely the process your lab developed to make a bioartificial heart?

Michael Barresi

Question 2

In order to create the bioartificial rat heart, you used cadaveric rat hearts. What types of scaffolds have been used before to provide the framework for regeneration, and does the decellularized cadaveric scaffold provide something unique that cannot be engineered?  Consequently, does that mean a bioartificial heart suitable for humans would require a cadaveric human heart for decellularization? Is this a practical requirement?

Kim Chi Ngo

Question 3

a. Why do de-cellularized samples have a significantly higher modulus than cadaveric rat ventricles or the fibrin gel?
b. In your re-cellularized rat hearts, you stimulated them electrically to observe their response. As your research progresses, how do you propose to maintain this electrical stimulation in a transplanted heart? Would you need to implant an artificial pacemaker or would you somehow be able to create a SA node?

Rachael Stein

Question 4

As a scientist using embryonic stem cells, can you provide us your opinions on how the political climate has impacted the field of embryonic stem cell research and regenerative medicine.  In particular how did President George W. Bush Administration’s action to restrict federal funding for embryonic stem cell research to only the 21 existing lines impact things? How did this change with President Obama’s Executive Order to lift up those barriers, however now with the pending Diesher and Sherley court case against federal funding for ESC research is this type of work effected?

Hyunwon (Sylvie) Bae

Question 5

I have type one diabetes and am aware that in some of the uncontrolled cases, pancreatic transplants are required because the pancreas plays so many roles that it is essential for survival even with insulin injections.  Can the procedures your lab has developed be used with an organ like the pancreas that has so many functions and synthesizes so many molecules?  Are there certain organs that would be more difficult using this system?

Carla M. Vélez

Question 6

With the current research into creating bioartificial organs, what types of stem cells appear to be showing the most promise: adult, iPS, or embryonic? In terms of cardiac tissue, what are major the advantages and disadvantages of each stem cell type?

Sofia Annis

Follow-up: In your 2009 article, you state that you seeded the decellularized freshly isolated neonatal cardiac cells. Could these cells be replaced with IPS cells? Do you see yourself working with ips cells in the future and do you foresee any advantages or disadvantages to working with them?

Rachael Stein

Question 7

By day 8, the bioartificial heart started to generate pump function. However, the heart’s pump function was only equivalent to about 2% of adult heart function and 25% of 16-week-old human fetal heart function. Why is this, and have you hypothesized and/or tested ways to strengthen the contractions of the bioartificial heart?

Jiyun Seo and Saira Huq

Question 8

Another ethical issue that comes to mind with this discovery is that if these bioartifical organs are effective and become an alternative to acquiring organs from donors, who decides who will be given first priority to receive these organs? Who do you see profiting, and depending on the cost do you see a scenario where only the wealthy will be able to afford such a life saving option? Can and should the distribution of these organs be regulated and by whom?

Nadine Mckenzie

Question 9

Within the newly-generated bioartificial heart, is there a niche for cardiovascular stem cells, so that if the heart comes across an injury in the future, can it repair itself?

Nguyen Huynh

Question 10

Currently in your opinion what are the most difficult obstacles to the progress of stem cell research and what will you and the Gentics Policy Institute do to overcome these obstacles?

Michael Barresi