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All About Stem Cells: What Are They And Where Do They Come From?

By Jessica Kelner, D.O. - February 5, 2020


The field is evolving so quickly now that our use of stem cells is evolving. The FDA’s governance on stem cells is also evolving. Even the language used to describe stem cells is evolving.
When we reference stem cells in regards to regenerative medicine, we are really talking about mesenchymal stem cells (MSCs).

A mesenchymal stem cell is an adult cell that performs as a messenger signaling cell that is very potent and signals tissue-specific stem cells and site-specific stem cells to activate. You can think of them as cellular packets of high potential that are directed to where the body has a need to fix something. In medical parlance, mesenchymal stem cells are “multipotent" adult cells, which can produce more than one cell type in the body, but not all types. MSCs are found in bone marrow, umbilical cord tissue, adipose tissue, and amniotic fluid.

MSCs can differentiate into osteoblasts (bone forming cells), adipocytes (fat tissue) and chondrocytes (Cartilage cells) as well as myocytes (muscle cells). MSCs have immunomodulatory effects. They secrete cytokines and immune receptors which regulate the microenvironment of the tissue.

Amniotic stem cells (ASCs) are a type of mesenchymal stem cells (MSCs). ASCs can develop into many different types of tissues such as skin, cartilage, cardiac, nerves, muscle, and bone. Consequently, ASCs have been implicated to provide many potential medical applications, especially in organ and joint regeneration.

Amniotic stem cells work really well for many, many people. Amniotic stem cells are obtained after a live birth C-section from a healthy mother. Amniotic stem cell come from the amniotic fluid, which has cells and growth factors and the micronized tissue from the amniotic sac, that will work as an allograft. An Allograft is tissue that is transplanted from one person to another to facilitate a structural component for regrowth. The FDA classifies the use of amniotic stem cells as a tissue allograft. The body can use it and build new tissue on top of it. It is almost like a mini-surgical procedure. You get growth factors and stem cells in the amniotic fluid, and more stem cells, plus a grafting effect from the micronized tissue.

Not every practitioner uses both the tissue and the fluid; not every company’s amniotic stem cell product has both. My preference is to use both when injecting joint/ligaments/tendons, for example, because it gives the patient the graft and stem cells.

The source of any kind of stem cell product is important. As is the case so often in life, some companies create a much better product than others.

Stem cells from amniotic tissue are a fabulous choice for professional athletes, for example, who want to get right back in the game. Different kinds of stem cells trigger different kinds of healing. The key is that amniotic stem cells do not trigger an inflammatory healing response. If we used stem cells from adipose tissue or bone marrow, athletes would be sidelined for about three weeks because the body would be using inflammation to promote the healing process. When platelets (clotting factors in our blood) and red blood cells are in the mix, you get an inflammatory response; stem cells from amniotic fluid/tissue do not contain these blood components. Amniotic stem cells are great for people who desire the least amount of down time.

Stem cells sourced from your own bone marrow are the most used stem cells in the world. Bone marrow was the original source of MSCs and is still widely used. Using bone marrow won’t necessarily give you the largest number of mesenchymal cells, but it gives you a nice mix of mesenchymal cells, growth factors, red blood cells, platelets, and hematopoietic cells (cells that make your blood regrow).

Blood and bone marrow stem cells were found to rescue patients with bone marrow deficiencies about 40 yrs ago. The result of this work produced the national bone marrow registry, which was established in the United States in 1986. Use of adult bone marrow-derived stem cells brought to the forefront, the limitations that these types of cells are thought to have. Bone marrow-derived stem cells are reported to be more difficult to extract from the marrow cavity, in normal aging, because the red marrow space changes to a yellow marrow (fat-filled) as a consequence of aging. Optimal stem cell aspirates from the marrow are found in young donors (18–19 yr of age).

Next to blood stem cells, the most widely studied stem cells in bone marrow are bone marrow-derived mesenchymal stem cells (BM-MSCs), also known as marrow stromal cells. In the adult, MSCs are found in highest concentration in the marrow cavity. MSCs are found at lower density in blood and in peripheral, adipose, and other tissues.

The procedure to obtain stem cells from bone marrow has gotten much simpler over the years. It is an out-patient procedure that takes about 45 minutes and requires only local anesthesia. The aspiration procedure is minimally invasive. A needle is used to withdraw bone marrow, which is the source of the stem cells. After the bone marrow is removed, it can be injected immediately to capture the platelets and all the other components in the marrow, or we can spin it down to concentrate just the stem cells, which are then injected directly into the site of the injury.

Note: People on blood thinners, people with cancer, and people with certain diseases are not candidates for bone marrow or adipose stem cell procedures.

Like bone marrow, adipose tissue is part of your own body. Adipose tissue is a fancy name for body fat. Adipose tissue stem cells (ASCs) are also considered as a type of mesenchymal stem cell (MSC). To obtain adipose tissue stem cells, a mini-liposuction procedure is performed to extract your own fat cells from just below the skin where stem cells are abundant. The tissue is mechanically micronized with filters to prepare it for immediate injection at the problem site.

There are more mesenchymal cells in fat cells than in bone marrow, and obtaining cells from adipose tissue can be less invasive than bone marrow (5). If a high number of mesenchymal cells is the primary goal, stem cells derived from adipose tissue will deliver.

As the name alludes to, these are sourced from the umbilical cords of healthy, newborn babies whose mothers have undergone a number of screening tests. The FDA classifies umbilical cord stem cells as a human tissue product. Umbilical cord stem cells may contain the highest number of those potent mesenchymal cells that signal healing of damaged body parts. These are adult stem cells meaning they are naturally limited in what other types of cells they can become which makes them very safe to use (3). Umbilical cord stem cells are also considered MSCs and are "multipotent", which means they are capable of forming many different cell types.

Over the last 20 years, umbilical cord blood has been shown to be therapeutically useful for rescuing patients with bone marrow-related deficits and inborn errors of metabolism (5). Umbilical cord blood offers advantages over bone marrow because cord blood does not require human leukocyte antigen (HLA) tissue matching.

MSCs can be isolated from umbilical cord blood, placenta, amniotic fluid, and from the tissue surrounding the umbilical cord vessels. The collection of MSCs from tissues that are discarded at birth is easier and less expensive than collecting MSCs from a bone marrow aspirate. During the collection of these tissues, there is no health impact on either the mother or the newborn. At least in theory, these cells may be stored frozen and then thawed to provide stem cells for therapeutic use decades after cryogenic storage.

There has never been a reported case of amniotic or umbilical stem cells – the two types of stem cells that you would source from someone else’s body – causing a rejection reaction. Stem cell therapy mimics a process that is ongoing in our body every day.

These are the most controversial type of stem cells of all sources. They are not allowed in the United States. They come to life when the egg and sperm first come together, first begin to multiply, and these first few cells are allowed to develop into every other kind of cell for a short period of time. Embryonic stem cells are "pluripotent". This means they can turn into any other type of cell in the body. They are not adult cells and that raises concern as to whether their use would promote cancer or other disorders. Because they are so primitive, it is hard to predict what they will do.

Some practitioners use what are called “culture expanded stem cells.” These cells are grown in a lab with nutrients. There is some evidence that if you grow them in a lab, they are not as effective in the body, so you do not get the same benefits. They are only used in the United States for research at this time.

The number of our mesenchymal cells decreases with age. At age 30, we have a lot more stem cells in our bone marrow and adipose tissue than we do at age 50 or 60. That means our body has decreased tissue repair capacity as we get older. This is why injecting stem cells, potent signaling cells and growth factors, can be very helpful.


Stem cells, as wonderful as they can be, are sometimes sold with a lot of hype that doesn’t stand up to reality. Whether stem cell therapy will work for you requires a thorough evaluation of both the type of your injury and the severity of your injury.

For mild to moderate injuries, there is a high likelihood that stem cells will work to repair the injury.

Technique is a critical part of the equation . Two physicians could treat the same exact injury with the same degree of severity and get different results because their technique is different, For example, if there is a patient with osteoarthritis of the knee joint, you would want to make sure to assess the tendons and ligaments surrounding the joint to look for instability and weakness. There is a good chance if these structures are not assessed for instability and treated, you will not get good long term results.

Stability of the joint or injured area is often overlooked and is critical to the healing process. It is not enough use stem cells to heal injured tissue, that is only half of the treatment course. To achieve long term success, the treatment needs to address both injured tissue and stability. Instability is not easy to see with an MRI or X ray. These images may show joint deterioration, but not the weakness in the supporting ligaments and tendons. Additionally, when we the X-ray or MRI is performed, our bodies are still. In daily life, we are anything but still and the still imaging techniques do not capture what happens when we are in motion. We want to identify the injuries limiting or causing an imbalance to our functional movement.

Our bodies are an intricate and complex balance of muscle, bone, and tissue. Muscles move our bones. Ligaments attach bone to bone and stabilize the joints. When ligaments become weak, this creates instability. This in turn causes the muscle to tighten (it is trying to act as a ligament) and that is why you lose range of motion and have pain or muscle spasms.

You may have heard from some people who received stem cell therapy for back problems such as degenerative disks or pinched nerves (radiculopathy) that they didn’t get the results they were hoping for. This may be an issue of technique. Many practitioners will do just one or two injections. To see results, you have to inject the surrounding ligaments in the back for stability. Stem cells can only fix so much if the instability is not also given the opportunity to be corrected. This can take more time, be more costly, and yield better results. You do get what you pay for.

Let’s go back to the issue of technique and why it's so important for the surrounding ligaments to be addressed. For example, let's look at someone with severe chronic degenerative arthritis in the knees. Over years, cartilage has been wearing down in the joint. It isn't happening in isolation though. The surrounding ligaments that were supporting the knee joint became weak/or chronically injured first. This is what allowed the joint to move in a way that put that unequal stress on the joint. The person may feel pain, which changes the way they walk and then puts even more stress on the ligaments, tendons, and surrounding muscles. The surrounding muscles, over time, change, even if you are working out or going to physical therapy; If your ligaments are weak, the body is going to use the muscle to protect that joint. There is considerable instability, which then creates friction. If only the joint is treated, pain will initially be less, but the cartilage will have a difficult time healing and you won't be pain-free long-term because you still have instability. On the other hand, if you also inject the ligaments surrounding the knee joint with stem cells or PRP (platelet rich plasma), you can stabilize the joint and then the cartilage will be able to heal because you addressed the whole problem, not just part of it.

Let’s take a moment to compare stem cell therapy for your knees versus surgery. Total knee replacement surgery tends to need to be repeated every 10 years. Surgery is invasive. The use of general anesthesia has been linked to dementia and immune system suppression (3).  If you go straight to knee replacement surgery, you can’t go back to stem cells. This is permanent.

Professional sports injuries, degenerative conditions in knees and hips, lower back pain, athletic hernias, abdominal muscle tears, carpal tunnel, golfer’s elbow, tennis elbow, shoulder injuries, rotator cuff tears, osteoarthritis in joints, ankle sprains, TMJ – these are the conditions to which stem cells would benefit. Stem cell injections have a very low risk of any side effects, and often our patients no longer need to be dependent upon pharmaceutical medications.


Stem cells maintain, heal, and regenerate tissues throughout our body. Without them, we would die because there would be nothing to replace exhausted cells or damaged tissue.
When stem cells are injected in the area of an injury, regardless of the source, we are injecting signaling cells that direct the body to produce a healing response in the tissue and organs.

For each patient, it comes down to these questions:
  • Are you candidate based on health issues, imaging, pain level, stability issues?
  • What result do you want?
  • What is likely to promote the best healing for you?
  • What is your budget?

Stem cell therapy can:
  • Repair tissue that is too damaged to heal on its own or just doesn’t heal properly: ankle sprains, knee meniscus tears, plantar fasciitis, ACL tears, rotator cuff tears, labral tears, arthritic joints, and more.
  • Regenerate tissue that is missing: cartilage in arthritic joints, cellular re-growth in trauma sites, reinforce muscle and connective tissue that is lost through the aging process.
  • Provide a source of immunomodulation: it balances out the pro- and anti-inflammatory forces in the body
  • Be used in cosmetic procedures to fight aging, such as microdermabrasion, wrinkles, and sunspots. With direct injections under the skin, we see collagen growth.
Covered by insurance? Most of these procedures are not yet covered by insurance.
Stem cell therapy helps you heal from degeneration and injuries, and many people return to a fully functional lifestyle free of medications and constant follow up visits to the doctor.

If you have more questions and would like to find out if you're a candidate for stem cell therapy, call us at 720-270-9559. You can also check out

1.Ceserani V, Ferri A et al. Angiogenic and anti-inflammatory properties of micro-fragmented fat tissue and its derived mesenchymal stromal cells. Vascular Cell, August 2016. 8(3) 

2.Mark L. Weiss* and Deryl L. Troyer, Stem Cells In The Umbilical Cord.
Stem Cell Rev. 2006 ; 2(2): 155–162. doi:10.1007/s12015-006-0022-y.

3.Lloyd DG, Ma D, Vizcaychipi MP. Cognitive decline after anaesthesia and critical care. Continuing Education in Anaesthesia, Critical Care & Pain. June 2012 

4.Oliver KT, Alexander RW. Combination of Autologous Adipose Derived Tissue Stromal Vascular Fraction Plus High Densiry Platelet Rich Plasma or Bone Marrow Concentrates in Achilles Tendon Tears. J Prolo, 2013; 5: e895-912

5.Omar MMS. Superior Proliferative and Tissue Regeneration Potential of Adipose Tissue-Derived Mesenchymal Stem Cells Compared to Bone Marrow: A Review. Insight In Stem Cells. 2015.

6.Tokiko Nagamura-Inoue, Haiping He. Umbilical cord-derived mesenchymal stem cells: Their advantages and potential clinical utility. World Journal Of Stem Cells. 2014 April 26; 6(2): 195-202