Rats, research and the road to new therapies

Don Reed

Don Reed has been a champion of CIRM even before there was a CIRM. He’s a pioneer in pushing for funding for stem cell research and now he’s working hard to raise awareness about the difference that funding is making.

In a recent article on Daily Kos, Don highlighted one of the less celebrated partners in this research, the humble rat.

A BETTER RAT? Benefit #62 of the California Stem Cell Agency

By Don C. Reed

When I told my wife Gloria I was writing an article about rats, she had several comments, including: “Oo, ugh!” and also “That’s disgusting!”

Obviously, there are problems with rats, such as when they chew through electrical wires, which may cause a short circuit and burn down the house. Also, they are blamed for carrying diseased fleas in their ears and spreading the Black Plague, which in 1340 killed half of China and one-third of Europe—but this is not certain. The plague may in fact have been transmitted by human-carried parasites.

But there are positive aspects to rats as well. For instance: “…a rat paired with  another that has a disability…will be very kind to the other rat. Usually, help is offered with food, cleaning, and general care.”—GUIDE TO THE RAT, by Ginger Cardinal.

Above all, anyone who has ever been sick owes a debt to rats, specifically the Norway rat with that spectacular name, rattus norvegicus domesticus, found in labs around the world.

I first realized its importance on March 1, 2002, when I held in my hand a rat which had been paralyzed, but then recovered the use of its limbs.

The rat’s name was Fighter, and she had been given a derivative of embryonic stem cells, which restored function to her limbs. (This was the famous stem cell therapy begun by Hans Keirstead with a Roman Reed grant, developed by Geron, and later by CIRM and Asterias, which later benefited humans.)

As I felt the tiny muscles struggling to be free, it was like touching tomorrow— while my paralyzed son, Roman Reed, sat in his wheelchair just a few feet away.

Was it different working with rats instead of mice? I had heard that the far smaller lab mice were more “bitey” than rats.  

Wanting to know more about the possibilities of a “better rat”, I went to the CIRM website, (www.cirm.ca.gov) hunted up the “Tools and Technology III” section, and the following complicated sentence::

“Embryonic stem cell- based generation of rat models for assessing human cellular therapies.”

Hmm. With science writing, it always takes me a couple of readings to know what they were talking about. But I recognized some of the words, so that was a start.

“Stemcells… rat models… human therapies….”  

I called up Dr. Qilong Ying, Principle Investigator (PI) of the study.

As he began to talk, I felt a “click” of recognition, as if, like pieces of a puzzle, facts were fitting together.

It reminded me of Jacques Cousteau, the great underwater explorer, when he tried to invent a way to breathe underwater. He had the compressed air tank, and a mouthpiece that would release air—but it came in a rush, not normal breathing.

So he visited his friend, race car mechanic Emil Gagnan, and told him, “I need something that will give me air, but only when I inhale,”– and Gagnan said: “Like that?” and pointed to a metal contraption on a nearby table.

It was something invented for cars. But by adding it to what Cousteau already had, the Cousteau-Gagnan SCUBA (Self Contained Underwater Breathing Apparatus) gear was born—and the ocean could now be explored.

Qi-Long Ying’s contribution to science may also be a piece of the puzzle of cure…

A long-term collaboration with Dr. Austin Smith centered on an attempt to do with rats what had done with mice.

In 2007, the  Nobel Prize in Medicine had been won by Dr. Martin Evans, Mario Capecchi, and Oliver Smithies. Working independently, they developed “knock-out” and “knock-in” mice, meaning to take out a gene, or put one in.  

But could they do the same with rats?

 “We and others worked very, very hard, and got nowhere,” said Dr. Evans.

Why was this important?

Many human diseases cannot be mimicked in the mouse—but might be in the rat. This is for several reasons: the rat is about ten times larger; its internal workings are closer to those of a human; and the rat is considered several million years closer (in evolutionary terms) to humans than the mouse.

In 2008 (“in China, that is the year of the rat,” noted Dr. Ying in our conversation) he received the first of three grants from CIRM.

“We proposed to use the classical embryonic stem cell-based gene-targeting technology to generate rat models mimicking human heart failure, diabetes and neurodegenerative diseases…”

How did he do?

In 2010, Science Magazine honored him with inclusion in their “Top 10 Breakthroughs for using embryonic stem cell-based gene targeting to produce the world’s first knockout rats, modified to lack one or more genes…”

And in 2016, he and Dr. Smith received the McEwen Award for Innovation,  the highest honor bestowed by the International Society for Stem Cell Research (ISSCR).

Using knowledge learned from the new (and more relevant to humans) lab rat, it may be possible to develop methods for the expansion of stem cells directly inside the patient’s own bone marrow. Stem cells derived in this fashion would be far less likely to be rejected by the patient.  To paraphrase Abraham Lincoln, they would be “of the patient, by the patient and for the patient—and shall not perish from the patient”—sorry!

Several of the rats generated in Ying’s lab (to mimic human diseases) were so successful that they have been donated to the Rat Research Resource center so that other scientists can use them for their study.

“Maybe in the future we will develop a cure for some diseases because of knowledge from using rat models,” said Ying. “I think it’s very possible. So we want more researchers from USC and beyond to come and use this technology.”

And it all began with the humble rat…

Asterias’ stem cell clinical trial shows encouraging results for spinal cord injury patients

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Jake Javier; Asterias spinal cord injury clinical trial participant

When researchers are carrying out a clinical trial they have two goals: first, show that it is safe (the old “do no harm” maxim) and second, show it works. One without the other doesn’t do anyone any good in the long run.

A few weeks ago Asterias Biotherapeutics showed that their CIRM-funded stem cell therapy for spinal cord injuries appeared to be safe. Now their data suggests it’s working. And that is a pretty exciting combination.

Asterias announced the news at the annual scientific meeting of the International Spinal Cord Society in Vienna, Austria. These results cover five people who got a transplant of 10 million cells. While the language is muted, the implications are very encouraging:

“While early in the study, with only 4 of the 5 patients in the cohort having reached 90 days after dosing, all patients have shown at least one motor level of improvement so far and the efficacy target of 2 of 5 patients in the cohort achieving two motor levels of improvement on at least one side of their body has already been achieved.”

What does that mean for the people treated? A lot. Remember these are people who qualified for this clinical trial because of an injury that left them pretty much paralyzed from the chest down. Seeing an improvement of two motor levels means they are regaining some use of their arms, hands and fingers, and that means they are regaining the ability to do things like feeding, dressing and bathing themselves. In effect, it is not only improving their quality of life but it is also giving them a chance to lead an independent life.

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Kris Boesen, Asterias clinical trial participant

One of those patients is Kris Boesen who regained the use of his arms and hands after becoming the first patient in this trial to get a transplant of 10 million cells. We blogged about Kris here

Asterias says of the 5 patients who got 10 million cells, 4 are now 90 days out from their transplant. Of those:

  • All four have improved one motor level on at least one side
  • 2 patients have improved two motor levels on one side
  • One has improved two motor levels on both sides

What’s also encouraging is that none of the people treated experienced any serious side effects or adverse events from the transplant or the temporary use of immunosuppressive drugs.

Steve Cartt, CEO of Asterias, was understandably happy with the news and that it allows them to move to the next phase:

“We are quite encouraged by this first look at efficacy results and look forward to reporting six-month efficacy data as planned in January 2017.  We have also just recently been cleared to begin enrolling a new cohort and administering to these new patients a much higher dose of 20 million cells.  We look forward to begin evaluating efficacy results in this higher-dose cohort in the coming months as well.”

People with spinal cord injuries can regain some function spontaneously so no one is yet leaping to the conclusion that all the progress in this trial is due to the stem cells. But to see all of the patients in the 10 million stem cell group do well is at the very least a positive sign. Now the hope is that these folks will continue to do well, and that the next group of people who get a 20 million cell transplant will also see improvements.

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Roman Reed, spinal cord injury patient advocate

While the team at Asterias were being cautiously optimistic, Roman Reed, whose foundation helped fund the early research that led to this clinical trial, was much less subdued in his response. He was positively giddy:

“If one patient only improves out of the five, it can be an outlier, but with everyone improving out of the five this is legit, this is real. Cures are happening!”

 

Young man with spinal cord injury regains use of hands and arms after stem cell therapy

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Kris Boesen – Photo courtesy USC

Hope is such a fragile thing. We cling to it in bad times. It offers us a sense that we can bear whatever hardships we are facing today, and that tomorrow will be better.

Kris Boesen knows all about holding on to hope during bad times. On March 6th of this year he was left paralyzed from the neck down after a car accident. Kris and his parents were warned the damage might be permanent.

Kris says at that point, life was pretty bleak:

“I couldn’t drink, couldn’t feed myself, couldn’t text or pretty much do anything, I was basically just existing. I wasn’t living my life, I was existing.”

For Kris and his family hope came in the form of a stem cell clinical trial, run by Asterias Biotherapeutics and funded by CIRM. The Asterias team had already enrolled three patients in the trial, each of whom had 2 million cells transplanted into their necks, primarily to test for safety. In early April Kris became the first patient in the trial to get a transplant of 10 million stem cells.

Within two weeks he began to show signs of improvement, regaining movement and strength in his arms and hands:

“Now I have grip strength and do things like open a bottle of soda and feed myself. Whereas before I was relying on my parents, now after the stem cell therapy I am able to live my life.”

The therapy involves human embryonic stem cells that have been differentiated, or converted, into cells called oligodendrocyte progenitors. These are capable of becoming the kind of cells which help protect nerve cells in the central nervous system, the area damaged in spinal cord injury.

The surgery was performed by Keck Medicine of USC’s Dr. Charles Liu. In a news release about the procedure, he says improvements of the kind Kris has experienced can make a huge difference in someone’s life:

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Dr. Charles Liu, Keck School of Medicine: Photo courtesy USC

“As of 90 days post-treatment, Kris has gained significant improvement in his motor function, up to two spinal cord levels. In Kris’ case, two spinal cord levels means the difference between using your hands to brush your teeth, operate a computer or do other things you wouldn’t otherwise be able to do, so having this level of functional independence cannot be overstated.”

We blogged about this work as recently as last week, when Asterias announced that the trial had passed two important safety hurdles.  But Kris’ story is the first to suggest this treatment might actually be working.

Randy Mills, CIRM’s President & CEO, says:

 “With each patient treated in this clinical trial we learn.  We gain more experience, all of which helps us put into better context the significance of this type of event for all people afflicted with debilitating spinal cord injuries. But let us not lose sight of the individual here.  While each participant in a clinical trial is part of the group, for them success is binary.  They either improve or they do not.  Kris bravely and selflessly volunteered for this clinical trial so that others may benefit from what we learn.  So it is fitting that today we celebrate Kris’ improvements and stop to thank all those participating in clinical trials for their selfless efforts.”

For patient advocates like Roman Reed, this was a moment to celebrate. Roman has been championing stem cell research for years and through his Roman Reed Foundation helped lay the groundwork for the research that led to this clinical trial:

This is clear affirmative affirmation that we are making Medical History!  We were able to give a paralyzed quadriplegic patient back the use of his hands! With only half a clinical dosage. Now this person may hold and grasp his loved ones hands in his own hands because of the actions of our last two decades for medical research for paralysis CURE! CARPE DIEM!”

It’s not unheard of for people with the kind of injury Kris had to make a partial recovery, to regain some use of their arms and hands, so it’s impossible to know right now if the stem cell transplant was the deciding factor.

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Kris at home: photo courtesy USC

Kris’ dad, Rodney, says he doesn’t care how it happened, he’s just delighted it did:

“He’s going to have a life, even if (the progress) stops just this second, and this is what he has, he’s going to have a better life than he would have definitely had before, because there are so many things that this opens up the world for him, he’s going to be able to use his hands.”


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