Neil Riordan PhD on Peri-lymphatic Stem Cell Treatment for Multiple Sclerosis

Stem Cell Pioneers featured Dr. Riordan in its February installment of “Ask the Doctor”, a monthly segment that features stem cell scientists and doctors answering questions from readers about stem cell therapy.

Over the next several days, we will share these questions and Dr. Riordan’s answers with our readers.

Question: I have heard from patients that you are doing intralymphatic stem cell injections. I think there are a lot of IntraLymph studies on other things like allergies, but none on stem cells that I can find. What is the reasoning behind this new route of administration? If stem cells get stuck in the lungs and we worry about that, why inject them directly into the lymph system where they would go to the spleen?

Dr. Riordan’s Answer: The goal of our treatments umbilical cord mesenchymal stem cells for patients with multiple sclerosis really has nothing to do with repairing the damaged or destroyed myelin in the lesions found in the brain and spinal cord. Because multiple sclerosis is first and foremost an autoimmune disease our goal is to address the immune dysfunction. At the root of the disease is a pool of immune cells called T-cells, which actively proliferate, cross the blood brain barrier, and attack myelin. Our primary goal then is to interfere with myelin-specific T-cell reproduction (something called “clonal expansion’). Mesenchymal stem cells (MSCs) have been shown in multiple studies to have the capacity to block this so-called clonal expansion of activated T cells. In a way MSCs immunosuppress, but unlike some drugs that suppress the immune system this specific blocking of activated T cells does not quash the entire immune system—the cells and their secretions only block the clonal expansion. Other drugs that suppress the immune system—for example hydrocortisone—have an effect on the entire immune system, which can increase the risk of the recipient to infectious diseases and even some cancers.

If it were the goal of the treatment to induce remyelination then certainly the route of delivery would be of greatest importance. You would want for the cells (or whatever proposed remyelination agent) to be as close to the lesions requiring the repair as possible. So I understand the rationale for the question.

In my opinion it will be difficult to successfully treat multiple sclerosis by remyelination alone because if you do not address the immune problem you will continue to lose myelin. Therefore, getting the cells to the lesions for myelin repair is not particularly important. Further support for this opinion is that there is very good evidence that the body has the innate ability to regenerate myelin without intervention. There are two good examples of this. The first example comes from a condition called Guillain–Barré syndrome. The syndrome is an autoimmune disease that results from an immune attack on the myelin of peripheral nerves. There is an ascending paralysis and the condition can be life threatening if the paralysis gets high enough to affect breathing. It is treatable and generally temporary. In 80% of the patients the underlying nerves are not irreparably damaged and there will be no long-term neurologic symptoms. 20% experience permanent nerve damage because the axons of the nerves are damaged. The good news is that the disease is temporary. The better news is that in the mild cases in which the axons were not destroyed, complete remyelination occurs—the body has the capacity to restore myelin.

The second example comes from a phenomenon seen with serial MRI images of the brains in people with MS. Fifty percent of these low intensity lesions known as “black holes” revert within one month of appearance, indicating that remyelination has occurred spontaneously.

Further support for the “treat the immune system and not the Central Nervous System” in MS comes from the work of several groups, including Northwestern University who are using chemotherapeutic “conditioning”, ie. wiping out the immune system (and the by-standing hematopoietic stem cells) followed by bone marrow reconstitution using previously harvested bone marrow stem cells. There are published results of many cases improving without anything having been done to address the myelin loss.
To the question of intra-lymphatic injections: There has been no work on “intra-lymphatic” injections. We are looking into peri-lymphatic (near the lymph nodes) injections of huMSCs for patients who are refractory to intravenous treatment.
Here is a little background on this subject: Dr. Arnold Caplan of Case Western Reserve, the scientist to first describe mesenchymal stem cells, was in Panama last year consulting with us. He also presented at a conference that we cosponsored. In one of my discussions with Dr. Caplan he casually mentioned that whenever they injected mesenchymal stem cells into the abdominal cavity of animals that did not have an active inflammatory process in there in the cavity the MSC’s would automatically go to the abdominal lymph chains. They were able to determine this because they use cells that were labeled with the florescent probe. I found this very interesting given that the 70-80% of the immune cells of your body reside in the abdominal cavity in and around the intestines.

The rationale for peri-lymphatic treatment is relatively simple. Firstly, the goal of therapy in autoimmune disease is to induce immune tolerance in the face of immune intolerance. The majority of the immune cells are found in the lymphatic (which includes the lamina propria) system of the gut. MCSs will, when lacking a more compelling inflammatory signal, migrate to the lymph nodes. Once in the lymph nodes they will migrate and interact with the immune cells (T-cells and T-cell priming dendritic cells). We know for a fact that MSCs interfere with dendritic cell priming of T-cells.

My book will be coming out in April. It will go into greater detail on this subject and many more. There are case histories as well as treatment protocols and rationale for each condition. Information about how to get the book “Mesenchymal Stem Cells: Nature’s Pharmacy” will be on www.Riordanbooks.com, as well as on www.amazon.com.

Panama’s First Umbilical Cord Stem Cell Clinical Trial for Rheumatoid Arthritis Approved by Comité Nacional de Bioética de la Investigación Institutional Review Board

Translational Biosciences Site Header
Panama City, Panama (PRWEB) January 14, 2014

Translational Biosciences, a subsidiary of Medistem Panama has received the county’s first clinical trial approval for the treatment of rheumatoid arthritis with human umbilical cord-derived mesenchymal stem cells (MSC) from the Comité Nacional de Bioética de la Investigación Institutional Review Board (IRB).

Rheumatoid Arthritis (RA) is an autoimmune disease in which the patient’s immune system generates cellular and antibody responses to various components of the joint such as type I collagen. As a result of this immune response, not only does joint destruction occur, but also other secondary complications such as pulmonary fibrosis, renal damage, and even heart damage. RA affects approximately 0.5-1% of the population in the United States.

Mesenchymal stem cells harvested from donated human umbilical cords after normal, healthy births possess anti-inflammatory and immune modulatory properties that may relieve RA symptoms. Because they are immune privileged, the recipient’s immune system does not reject them. These properties make MSC interesting candidates for the treatment of rheumatoid arthritis and other autoimmune disorders.

Each patient will receive five intravenous injections of umbilical cord stem cells over the course of 5 days. They will be assessed at 3 months and 12 month primarily for safety and secondarily for indications of efficacy.

The stem cell technology being utilized in this trial was developed by Neil Riordan, PhD, founder of Medistem Panama. The stem cells will be harvested and processed at Medistem Panama’s 8000 sq. ft. laboratory in the prestigious City of Knowledge. They will be administered at the Stem Cell Institute in Panama City, Panama.

The Principle Investigator is Jorge Paz-Rodriguez, MD. Dr. Paz-Rodriguez also serves as the Medical Director at the Stem Cell Institute.

“While this is just the first step, it is our hope that Panama’s rapid emergence as a leader in applied stem cell research will lead to safe, effective treatments for debilitating diseases such as rheumatoid arthritis and serve to benefit all Panamanians who suffer from it in the not-too-distant future,” said Ruben Berocal, M.D., National Secretary of Science, Technology and Innovation (SENACYT). “Oversight by the National Committee for Investigational Bioethics ensures patient safety by demanding ethical transparency and compliance with the highest levels of international standards,” he added.

For detailed information about this clinical trial visit http://www.clinicaltrials.gov. If you are a rheumatoid arthritis patient who has not responded to disease modifying anti-rheumatic drugs (DMARD) for at least 6 months you may qualify for this trial. Please email trials(at)translationalbiosciences(dot)com for more information about how to apply.

About Translational Biosciences

A subsidiary of Medistem Panama Inc., Translational Biosciences was founded solely to conduct clinical trials using adult stem cells and adult stem cell-derived products.

Translational Biosciences Web Site: http://www.translationalbiosciences.com

Email: trials(at)translationalbiosciences(dot)com

About Medistem Panama Inc.

Since opening its doors in 2007, Medistem Panama Inc. has developed adult stem cell-based products from human umbilical cord tissue and blood, adipose (fat) tissue and bone marrow. Medistem operates an 8000 sq. ft. ISO 9001-certified laboratory in the prestigious City of Knowledge. The laboratory is fully licensed by the Panamanian Ministry of Health and features 3 class 10000 clean rooms, class 100 laminar flow hoods, and class 100 incubators.

Medistem Panama Inc.
Ciudad del Saber, Edif. 221 / Clayton
Panama, Rep. of Panama

Phone: +507 306-2601
Fax: +507 306-2601

About Stem Cell Institute Panama

Founded in 2007 on the principles of providing unbiased, scientifically-sound treatment options, the Stem Cell Institute has matured into the world’s leading adult stem cell therapy and research center. In close collaboration with universities and physicians world-wide, our comprehensive stem cell treatment protocols employ well-targeted combinations of autologous bone marrow stem cells, autologous adipose stem cells, and donor human umbilical cord stem cells to treat: multiple sclerosis, spinal cord injury, osteoarthritis, rheumatoid arthritis, heart disease, and autoimmune diseases. To-date, the Institute has treated over 2000 patients.

For more information on stem cell therapy:

Stem Cell Institute Website: https://www.celllmedicine.com

Stem Cell Institute
Via Israel & Calle 66
Plaza Pacific Office #2A
Panama City, Panama

Phone: +1 800 980-STEM (7836) (USA Toll-free) +1 954 636-3390 (from outside USA)
Fax: +1 866 775-3951 (USA Toll-free) +1 775 887-1194 (from outside USA)

Autologous Cell Therapies Do Not Represent a Public Health Risk and Should Not Be Regulated Like Drugs

SevOne Founder and Stem Cell Institute patient, Michael Phelan discusses what’s financially at stake for scientists, universities, drug companies, and the FDA who oppose autologous stem cell therapy and lobby for patients’ own stem cells to be regulated as drugs.

VIEW FULL ARTICLE

Forbes interview with Michael Phelan from Feb 2013: One Man’s Reluctant Tour for Adult Stem Cells by John Farrell

Excerpt:

“I chose the Stem Cell Institute because they published their research in Translational Medicine. In addition, I corresponded with physicians and researchers experienced in Autologous Stem Cell treatments, including Roger Nocera, author of Healing Cells – Cells that heal us from cradle to grave, and I also listened to Arnold Caplan of Case Western.

So, at a Johns Hopkins managed hospital in Panama I had a mini-liposuction procedure. From my adipose-fat tissue they separated and expanded my cells, which took about a week then they gave to me in an IV.

I had visual problems for over a year before treatment, including double vision. After my first treatment in May of 2012, my vision problems resolved and I was able to continue driving. My mental and physical energy improved dramatically. A number of other problems improved. So, I was pleased with the outcome.”

Professor Arnold Caplan discusses mesenchymal stem cell therapy for multiple sclerosis

Professor Caplan is “The father of the mesenchymal stem cell (MSC)”. In this clip, he describes a mouse experiment using human MSCs in a mouse model of MS. The experiment shows that it’s possible to place human cells in mice that have normal immune systems. He continues to discuss the astounding results.

Volume two of stem cell research benefit album features Thee Oh Sees, Cave Singers, Dr. Dog members and more

Stem cell therapy recipient Ryan Benton's follow-up album, Coming Together for a Cure

Stem cell therapy recipient Ryan Benton’s follow-up album, Coming Together for a Cure

Now, a second volume is being released with a whole new line up, which includes Thee Oh Sees, Cave Singers, and members of Dr. Dog (via bands Golden Boots and Springs). Coming Together For A Cure, Vol. 2, which will be released 29 October, will also feature Benton’s band Sunshine Dreamers.

See the full track listing below, as well as a documentary about Benton’s triumphant recovery, against all odds, and how he has to travel outside of the U.S., where stem cell treatment is banned, to acquire his treatment.

Coming Together For A Cure, Vol. 2 Tracklist
01. Miracle Days – “Miracle Days”
02. Springs – “Waste My Time”
03. Thee Oh Sees – “The Factory Reacts”
04. The Wonder Revolution – “Cloud Wonder Sky”
05. Music Wrong – “Clyde”
06. Student Film – “Facts and Values”
07. Shine Brothers – “So Many People”
08. Elf Power – “1494″
09. Cave Singers – “Ohio Nights”
10. Golden Boots – “Be My Champ”
11. Gentle Ghost – “Oblivion Tide”
12. Sleeping in the Aviary – “Long Gone”
13. Sunshine Dreamers – “Empty Nest”
14. Bellafonte – “Sea of Trees”
15. Beau Jennings & the Tigers – “Sweet Action”

Cutting edge: Surgeon uses stem cell surgery on stem cell researcher Neil Riordan PhD

Wise County Messenger
By Bob Buckel | Published Wednesday, July 31, 2013

A middle-aged man named Neil got his knee “scoped” in a Decatur operating room recently.

That’s not unusual. Wise Regional Health System’s OR is a busy place, and arthroscopic knee surgery is a common procedure.

But this particular knee had an interesting twist.

Wade McKenna MD and Neil Riordan PhD in OR

IN THE OR – Dr. Wade McKenna performs stem cell surgery on stem cell researcher Neil Riordan PhD.

The physician doing the surgery, Dr. Wade McKenna, met his patient when they shared a podium at a medical conference in February. The patient, Neil Riordan, has a Ph.D. in molecular biology and is one of the leading stem cell researchers in the world.

Riordan’s surgery, a fairly routine cleanout, ended with the insertion of a concentrate of his own stem cells back into the knee, to promote healing, foster cartilage regeneration, and reduce inflammation and the possibility of infection.

It’s a procedure Dr. McKenna has done more than 1,500 times, right here in Decatur, for a variety of fractures, cartilage and tendon injuries. Last year he operated on patients from four countries.

“It’s been mostly in the last three years, and really, the bulk of those in the last year,” he said. “It’s not like I have a newspaper ad that says ‘Stem Cell Surgeon.’ It’s just, you do a patient whose doctor calls you, and that doctor has a family member that he calls you about. Almost all these patients know someone I’ve already taken care of.”

He cited a doctor in Oklahoma who flew his wife down for knee surgery, and a radiologist who reviewed before and after MRIs of one of his procedures and saw actual cartilage growth.

“He calls me on the phone and says, “How did you do that? I’ve never seen condromilatia going the other direction. I’ve only seen it get worse.’” McKenna said. “He ends up sending his father-in-law, who’s from Canada, down to have the surgery. And that guy from Canada goes back and tells… so that’s how it’s happened.”

The surgeries are mostly routine – but the addition of bone marrow-derived stem cells afterward is a game-changer.

“Stem cells change the environment for healing in the joint,” Dr. McKenna said. “It’s like finding the light switch in a dark room. It looks like stem cells are the sentinel cells, the messenger cell – the light switch.

“It makes a substantial difference,” he added.

The journey that brought Neil Riordan to an operating table in Decatur started in Florida.

In February, at the International Stem Cell Society Conference in Fort Lauderdale, he spoke about research he’s doing in Panama that involves taking stem cells from a patient’s own fat, drying them, multiplying them and re-injecting them into the patient to promote healing.

McKenna spoke later about the technique he’s using. His method caught the researcher’s interest in part because it’s one of the few stem cell applications that’s legal in the U.S.

After he presented his results – broken clavicles to ankles to shoulders to arthritic knees – Riordan was interested enough to invite McKenna to dinner.

“He said he wanted to talk to me about some of the clinical experience I’ve had,” McKenna said. “He had not, to that point, been exposed to anyone who had that much experience with bone marrow-derived stem cells.”

Since then, they’ve gotten together several times – Riordan lives in Dallas and has a lab in Farmer’s Branch – and have “gone through a lot of research together,” McKenna said.

And somewhere in there, Riordan decided he might be a candidate for McKenna’s procedure.

CLEANING IT UP

“Neil saw all these films I’d taken and thought, ‘I’m ignoring a bunch of loose stuff floating around in my knee.’” McKenna said.

“It was only a couple of weeks ago – we’d been looking at a lot of cell cultures, and spending a lot of time in the lab in Dallas, and he finally just said, ‘Examine me. Put your hand here.’”

It was quickly obvious to the experienced surgeon that his research partner needed some work.

“I thought, ‘What are you doing?’” McKenna said. “He’s got locking, catching, giving way. I tell people all the time, you can ignore pain and swelling, but you can’t ignore mechanical symptoms. If something’s getting caught in your knee, it makes pretty intuitive sense to take that out, and your knee will feel better.”

To that point, Riordan’s focus had been simply on the application of stem cells – not combining it with surgery to clean out the joint and improve its mechanical function. Visiting with the surgeon, it made sense to combine the procedures.

Riordan himself explained it in an interview prior to his surgery.

“I still have stem cells in my bone marrow,” he said. “He’s going to pull some of those out and put them in the knee, the place where they’re needed.”

Riordan said the idea is to help the knee heal like it would have when he was much younger.

“When you’re young, you have a whole bunch of stem cells,” he said. “All we’re doing is just putting more of them in the right place at the right time to help people get over stuff. That’s what it boils down to.”

Riordan’s torn ACL, meniscus damage, adhesions and other knee problems were the result of an injury in 2002 where his knee swelled up, then “kind of” got better, McKenna said.

In surgery, to the constant beeping of the heart monitor and the ree-ree-ree of the pedal-operated instrument shaving off debris and vacuuming it out, the surgeon narrated while he operated.

“Just getting all the junk out of your knee, while it doesn’t give you a new knee, it certainly turns back the hands of time a little bit,” McKenna said. “He was just walking around, doing everything on this without seeking treatment.”

Fluid circulated through the knee and everyone watched the instruments on multiple big-screen television monitors in the OR.

“It didn’t make a lot of sense to start squirting stem cells into his knee until you clean it out a little bit,” McKenna said. “Even with the greatest stem cells in the world, if you just squirt it into that crummy knee with all that loose junk – none of that was going away.

“At least now, you see the difference in the joint. This has a chance of healing.”

After trimming for over an hour, removing frayed cartilage, bone spurs and adhesions, McKenna was ready to inject the bone-marrow aspirate that had been spinning just a few feet away.

THE KEY INGREDIENT

Prior to going into the knee, McKenna harvested bone marrow from Riordan’s left hip-bone and delivered it to a technician who put it into a specially-designed centrifuge.

Using the patient’s own stem cells makes the surgery legal in the U.S. Concentrating the bone marrow with a centrifuge makes it much more effective, based on the results McKenna has observed.

“A lot of doctors, when I say we’re doing bone marrow draws, they say there’s no stem cells in an adult,” he said. “That’s just not true. We’ve done the cell counts. I get over a million cells out of this harvest.”

He said the injection of stem cells accomplishes the same thing as microfracture – cracking the joint surface to bring bone marrow to the surface. It just does it better.

“In my mind, it’s not a big leap of faith to think that if a couple of drops of bone marrow from a worn-out knee help it heal, what would the equivalent of 110 ccs of spun-down, concentrated bone marrow with only the best parts do?

“That’s how we invented this surgery. No one had ever done microfracture surgery with bone marrow spread, and we did that in Decatur about five years ago.”

McKenna said the bone marrow from the ileac crest – the hip-bone – has more stem cells and growth factors than what’s in the knee – or on the market.

“There’s a patch that has about 60,000 donor stem cells and you can use that to help tendons heal,” he said. “But would you rather have 60,000 donor stem cells from someone else, that only have a viability of about 75 to 80 percent, or would you rather have 1 to 2 or 3 million of your own stem cells, with a viability of over 90 percent, that were taken at the time?

“They haven’t been freeze-dried, they haven’t been processed, they’re not from someone else – they’re yours. It’s a no brainer.”

“And the stem cells are delivered in a ‘slurry’ of concentrated growth factor,” he said.

“Now we’re on the right track, because the trophic factors are how you heal anyway. It’s how tendon heals, muscle heals, it’s how the body grows cartilage, grows tissue. It’s what stimulates growth and healing.

“We’re not doing anything abnormal,” he added. “This is the body’s normal physiology and reaction to disease. All we’re doing is adding a little gas to the engine.”

STEM CELL PIONEERS

Riordan, who has written more than 60 articles and chapters in two textbooks, speaks all over the world about stem cell therapy.

His research in Panama focuses on amniotic stem cells, taken from the “afterbirth” – the umbilical cord and amniotic sac – which would normally be disposed of after a baby is born.

“The amniotic membrane is actually what covers the baby in the womb, and that is what we use,” Riordan said. “There are 120-200 million stem cells inside of an amniotic membrane. They help in healing, decrease inflammation, decreasing adhesion formations, which is a real problem in surgery, particularly spine surgery. They promote and stimulate regeneration.”

Riordan’s clinic, Medistem Panama, is in an area just outside of Panama City called the City of Knowledge. Several major universities and research labs have located facilities there because of tax incentives and relaxed regulation.

Both stressed that the research in Panama uses amniotic tissue – not fetal tissue. Most stem-cell researchers reject the use of fetal tissue both for ethical reasons and because they’re simply not needed.

“The big political uproar about stem cell research is misguided,” he said. “Nobody is using fetal tissue. The only tissue that’s used is either the patient’s own tissue, or, better, amniotic tissue. That amniotic membrane is a very rich source of mesenchymal stem cells. That’s where a lot of Neil’s research is now.”

Riordan believes the FDA’s regulation of stem cells is misguided.

Speaking at a conference last July in Arizona, he said the FDA needs to view stem cells as what they are – human tissue – not a drug. He pointed out that hearts, lungs, kidneys, corneas, skin and other organs are transplanted in the U.S. every day, all without FDA approval.

“The drugs that suppress your immune system so you can receive that heart and survive – those are FDA approved, but the transplant isn’t,” he said. “It’s a procedure. It’s exempt.”

“I think ultimately these (stem cells) should be exempt as well, and should fall under the practice of medicine. That’s my opinion.”

For now, McKenna’s groundbreaking use of stem cells continues to pile up impressive results, providing clinical backup for the research done by people like Riordan.

And every day, it becomes more obvious that the use of stem cells holds the potential for healing across the entire spectrum of human suffering.

“Now, it’s not only about keeping your cartilage from wearing out, it’s about, ‘Can we grow cartilage and help you heal the joint?’” McKenna said. “The answer to that right now is yes-ish. In the not-too-distant future, the answer is yes.”

“It’s an exciting field,” Riordan said.

Umbilical Cord Stem Cells: Regeneration, Repair, Inflammation and Autoimmunity – Neil Riordan PhD (Part 2 of 2)

In part 2, Dr. Riordan discusses how mesenchymal stem cells can affect tissue repair in spinal cord injury and in heart failure; benefit to heart is not the actual MSCs modeling new tissue. It is due to the trophic effects of MSC secretions; In rats, severed spinal cords re-grew after MSCs were implanted but the human MSCs did not form new cord tissue. The trophic factors secreted by the MSCs enable the spinal cord to repair itself.; Trophic factors from MSCs modulate the immune system by blocking clonal expansion of cytotoxic T-cells; There are 35 ongoing clinical trials using mesenchymal stem cells for autoimmune diseases; Safety of donor MSCs; Every mother has MSCs from each baby she has carried; Mothers have a lower incidence of autoimmune disease; Lifespan of mothers increased linearly with each child up to 14; There are 85 ongoing clinical trials using donor MSCs. Allogeneic MSCs from bone marrow have been approved in Canada and New Zealand to treat graft vs. host disease; limbal cells used in corneal transplants are MSCs; MSCs are useful in preventing donated organ rejection; glioma growth was found to be inhibited by MSCs; MSCs eliminated breast cancer in rats.

VIDEO – The Science of Mesenchymal Stem Cells and Regenerative Medicine – Arnold Caplan PhD (Part 6)

In part 6, Prof. Caplan discusses Trophic properties of mesenchymal stem cells; MSCs for heart disease; MSCs homing to heart injury site and also to skin incision site; MSCs limit left ventricular thinning following infarction; Trophic properties of MSCs: anti-apoptotic, anti-fibrotic, anti-scarring, angiogenic, mitotic; phase 1 data for allogeneic MSCs show fewer arrhythmias, prompt heart rate recovery, and improved lung function; autologous adipose tissue-derived stromal vascular fraction for treatment of chronic heart disease; Active mesenchymal stem cell clinical trials around the world; Induction therapy with autologous MSCs in kidney transplants; MSCs can coax neural stem cells to become oligodendrocytes, curing mice with MS using allogeneic human MSCs.

VIDEO – The Science of Mesenchymal Stem Cells and Regenerative Medicine – Arnold Caplan PhD (Part 4)

In part 4, Prof. Caplan talks about isolating mesenchymal stem cells from bone marrow using specialized; calf serum choosing different assays to prove multipotency – osteogenesis, chondrogenesis, adipogenesis; point of care with autologous bone marrow in orthopedic surgery; tissue engineering bone with lineage restricted MSCs; banking bone discarded bone marrow from orthopedic surgeries for future use;

The Science of Mesenchymal Stem Cells and Regenerative Medicine – Arnold Caplan PhD (VIDEO Part 3)

In part 3, Professor Caplan discusses the science behind mesenchymal stem cells: sources of mesenchymal stem cells (MSCs), because all MSCs are pericytes one can find them in any tissue that has blood vessels, pericytes express markers of MSCs, frequency of pericytes in human tissue, most abundant source of pericytes is adipose (fat) tissue, adipose-derived stem cells, how MSCs are separated from fat, chemistries MSCs from different tissues are not the same, MSCs function at sites of injury, mesenchymal stem cell homing in mice, MSCs don’t make fat, they don’t make muscle. They come back as pericytes, and not all pericytes are MSCs.