In the Stem Cellar: restoring vision, a visionary on mini-organs and restoring circulation to limbs

Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Eyes owned the web this week. When your work includes any form of electronic communication, you worry about how many eyes see a page of content. Well this week you could not be anywhere near the internet and not see lots of pages about the eye. Two studies published in Nature offered such great hope for restoring vision robbed by cataracts that no media outlet could resist covering these fairly complex and scientifically elegant papers.

In one paper, researchers announced they had corrected the vision of a dozen young children born with cataracts by enabling their own native stem cells in the eye. The team from the University of California, San Diego, the University of Texas Southwest Medical Center in Dallas, and Sun Yat-Sen University in Guangdong, China, said their procedure resulted in better vision than traditional transplantation of a donor lens for the clouded eye.

 “An ultimate goal of stem cell research is to turn on the regenerative potential of one’s own stem cells for tissue and organ repair and disease therapy,” said Kang Zhang of the UCSD team in a story in Times of San Diego.

 In the other research report a team from Osaka University in Japan and Cardiff University in the UK used iPS type stem cells to create complex tissues that mimicked several parts of the eye. One was the cornea, which they implanted into rabbits and restored their vision. Genetic Engineering News wrote the piece with the most detail on this study and in that article the team notes the procedure is not yet ready for humans but they are working on it.

The web site for CTV in Canada did one of the better pieces trying to talk about both studies. It included quotes from a commentary piece in the same issue of the journal by Julie Daniels of the University College London:

 “These two studies illustrate the remarkable regenerative and therapeutic potential of stem cells.”

 

organs-on-chips

Organs on chips at the Wyss Institute

The art of designing organs.  Last spring the Museum of Modern Art in New York added some “organs-on-chips” to its collection. That exhibit became the jumping off point for a commentary in a special issue of the journal Cell on the biology of communication. One of the leaders in applying systems approaches to bioengineering, Donald Ingber of the Wyss Institute at Harvard wrote the commentary, and a university press release got picked up by a few outlets including Medical News Today.

Ingber describes the organs on chips as a great way to analyze how organs function and how they fit in with the overall function of the body.  And he hopes they will eventually lead to replacement parts.

 “We’re not trying to rebuild a human organ,” said Ingber. “We’re trying to develop culture environments for living human cells with the minimal design features that will induce them to reconstitute organ level structures and functions to mimic the physiology that we see in the human body.”

He sees particular power in such mini organs when paired with stem cell technology.  In particular, he noted the potential to test drugs on a patient’s own mini-organ grown from their own genetically identical cells using iPS type stem cells.

 

Help for poor circulation in limbs.  Just by its name, critical limb ischemia sounds like something nasty that you do not want to have. Its root cause, blood vessel narrowing, usually in the legs, causes severe pain and often leads to amputation. Up to now efforts to use growth factors to create new blood vessels or to use donor stem cells to induce new vessels or replace muscle damaged by poor circulation have not worked.

Karen Christman

UCSD’s Karen Christman

Now, a team at the University of California, San Diego, is getting a “patient’s” own stem cells to do the job by giving them the right environment. The patients in this case are rats. They injected the damaged area with a gel made from the scaffold left behind when you wash the cells from muscle tissue. Many studies have shown that this extracellular matrix holds signals that can instruct stem cells and other cells to create appropriate tissues. It worked in the four-legged patients.

 “This is a unique approach that not only helps repair the damaged vascular system, but also helps restore muscle tissue,” said Karen Christman in a story posted by Scicasts adopted from a university press release.

To verify the improvement they analyzed which genes were activated in the area of the injections and showed that the inflammatory response was damped while blood vessel and muscle growth genes were activated.

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