US Stem Cell Clinic Review

Regenerative Wellness Clinic Weston FL

One of the most interesting sagas in regenerative medicine has been US Stem Cell. The clinic recently came on my radar again when I was asked to give a second opinion to a US Stem Cell patient. Hence, I got a chance to dig deep into what US Stem Cell Clinic is doing with bone marrow and as an expert in that space, I thought I would review the clinic. However, a bigger reason for this blog is also to review how not to perform a bone marrow concentrate procedure. Finally, what I unearthed at US Stem Cell Clinic (aka Regenerative Wellness Clinic) is pretty shocking.

US Stem Cell Clinic

us stem cell clinic

US Stem Cell Clinic is primarily located in Weston, Florida and also has clinics in The Villages and in West Palm Beach. In looking at the website, the clinic still lists “Kristin Comella, Ph.D.” as the Chief Scientific Officer of US Stem Cell. This was a surprise, as Kristin Comella was accused of having a fake Ph.D. Basically, she had completed coursework at FIU toward a real Ph.D. and then decided to complete her dissertation at a “university” in Panama which has no campus that was started by a gentleman who granted himself a Ph.D. In the end, she was let go by US Stem Cell as this statement in a recent SEC filing shows: “Effective September 1, 2019, Kristin Comella resigned as a member of the Board of Directors of the Company and has left her position as Chief Scientific Officer. There were no disagreements by Ms. Comella as to the Company’s operations, policies or practices.” All of this appears to have happened due to the fact that Comella was the lead clinical force behind the blinding of several South Florida patients when a fat stem cell mix was injected into their eyes.

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One Patient’s Experience

Over the holidays, a physician colleague reached out to me about a patient who was an ex-power lifter who had gone to US Stem Cell Clinic in Weston, Fl. The patient had severe arthritis in both knees as well as “Adhesive Capsititis” in his shoulders as well as instability and arthritis. Basically, he has four messed up joints. His US Stem Cell treatment failed, hence the reason I was being asked to provide a second opinion. From reviewing his notes, are there are obvious reasons his treatment didn’t work? By teaching you why you can hopefully begin to filter out low quality orthopedic regenerative medicine care from high-quality care.

A Serious Lack of Standards

Most patients believe that if they get a named medical procedure, like a knee replacement, that the quality of that procedure varies only minimally between physicians. While that’s mostly true in situations where the procedure being performed is part of rigorous US Residency or Fellowship training requirements, this is specifically not true in looking at stem cell treatments. In fact, in this wild west environment, since there are few standardized educational systems and many doctors learn what they know at a weekend course, you can expect troubling differences in quality from clinic to clinic.

The First Quality Metric for a Bone Marrow Stem Cell Procedure-The Aspiration

Bone marrow concentrate is a procedure that has many names, one of which is a bone marrow stem cell procedure. This is because the bone marrow is rich in mesenchymal and other stem cells. This is what this patient had at US Stem Cell Clinic.

The procedure begins with the doctor taking the marrow aspirate, which is basically using a specialized needle to remove what looks like thick blood from the back of the hip area. This is called a BMA which is short for “Bone Marrow Aspiration”. This procedure, if numbed correctly is comfortable for the patient, but the problem is that the quality of the BMA is tied directly to stem cell yield (1-3). Meaning a BMA performed correctly will maximize the number of stem cells in the aspirate and one performed poorly will minimize the number of stem cells. The BMA at US Stem Cell, based on the patient’s description and the medical records I reviewed, was done very poorly. Let me explain.

The way to maximize the number of stem cells in a BMA is counter-intuitive. You would normally think that you should just take out the highest volume possible which would maximize stem cell number. However, this actually reduces stem cell numbers because the marrow space communicates with the peripheral blood circulation, which is stem cell poor. Hence, anything you draw over 5-10 ml (1-2 teaspoons) at a given site is just collecting mostly stem cell poor blood and not stem cell rich bone marrow aspirate (the cells that normally live in the bone marrow). Hence, you need to take smaller volumes from many sites to maximize stem cell yield. What was done at US Stem Cell?

From reviewing the notes as well as speaking with the referring physician who understands proper BMA technique, it looks like they took a huge amount (150 ml) of bone marrow aspirate which was obtained from one site on one side of the pelvis. Basically ensuring that the patient would have few stem cells. Why do this? I’ve seen this happening at many clinics and the only thing that seems to make sense is that it’s easier and faster for the doctor, as a single site 150 ml draw can take 5-10 minutes from start to finish versus a proper multi-site draw with many 5-10 ml pulls of bone marrow can take 40 minutes.

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The Second Quality Metric-Who Does the Procedure

You would think that if you pay big bucks for a bone marrow concentrate procedure, that you would get an expert super-specialist physician performing the BMA. However, this didn’t happen for this patient, who instead had his BMA performed by a PA. What’s that? A physician’s assistant who generally has about 1/3 of the training of a physician super-specialist. Why? In my opinion, when clinics use PAs there’s only one reason, to reduce the cost of providing care to maximize profit.

In addition, US Stem Cell has a long history of using providers with inadequate training. For example, the blinding of three patients by injecting fat stem cells into their eyes happened when a nurse practitioner performed these procedures. Would this have happened if an experienced ophthalmologist had performed the procedure? From speaking with my ophthalmology colleagues, they tell me that the eye injection performed is an advanced procedure that should only be performed by a fellowship-trained ophthalmologist.

The Third Quality Metric-Dosing

Dose is a critical concept in medicine. Give the patient too low a dose and nothing happens. However, if the dose is right, the patient responds. Is there a right dose of bone marrow concentrate? Yes, several studies have shown a relationship between orthopedic outcomes and the number of stem or total cells in the sample (4-6). However, here, we already know that the bone marrow taken likely had fewer stem cells than it could have had if the BMA was performed correctly. In addition, the patient discussed that he had all four joints treated at once. Based on our knee arthritis dosing paper and using the data from our lab, the chances of a 59-year-old man having enough cells to treat 4 joints at once is almost nil. Meaning, the clinic likely dramatically under-dosed all treated joints.

A Name Change and Breaking the Law?

First, the patient provided his physician a copy of this email:

regenerative wellness center 2

First, who is Regenerative Wellness Clinic? The three clinics listed on that website all share the exact same addresses as the former US Stem Cell Clinics and the Weston number has yet to change it’s message that still says “US Stem Cell Clinic”, so this is a clear rebranding of US Stem Cell. More interesting is the fact that, in my opinion, the clinic is describing an illegal treatment. Let’s dig in.

US Stem Cell Clinic and it’s parent company recently got in hot water for using an illegal drug product known as adipose Stromal Vascular Fraction (SVF). This fat stem cell procedure was against the law and when the company lost the case the FDA had filed, I was told that they promptly changed to bone marrow treatments. Given the clinic’s track record of treating everything from urologic to neurologic disorders, this was really concerning for providers who were trying to legitimize orthobiologhics and publishing the research to try to make this therapy go mainstream.

The email above is describing that US Stem Cell Clinic is going to send this patient’s fat or bone marrow to a lab where the cells will be banked and culture expanded. What does that mean? That the cells will be grown to larger numbers in a lab. These cells will then be sent back to US Stem Cell Clinic (aka Regenerative Wellness Centers) for reinjection. The problem? This is clearly illegal. In fact, a federal judge ordered US Stem Cell to destroy their banked stem cells.

I have blogged on the continued use by US Stem Cell of stem cell banking and culture expansion. However, I was certain that given the federal injunction against them that they would have stopped offering this treatment. Why? This is just as illegal as the fat stem cell treatment the clinic was already busted for by the FDA. So is US Stem Cell Clinic still offering these services after an FDA injunction? Yes, I can confirm that I spoke to the Weston clinic at approximately 12:40 pm MST on 1/6/19 and was clearly told that they would send a patient’s bone marrow out to an FDA registered lab that would culture the cells and send them back.

The upshot? The bottom line is that, based on everything I reviewed, this patient received a low-quality bone marrow stem cell procedure at US Stem Cell Clinic. While I don’t know if I can help him using a high-quality bone marrow concentrate or other procedures, I can say that this procedure could have been performed at a much higher level by physician super-specialists with expertise in this area. I can also say that given my understanding of the law, US Stem Cell Clinic (aka Regenerative Wellness Center) is continuing to violate FDA regulations.



  1. Muschler GF1, Boehm C, Easley K. Aspiration to obtain osteoblast progenitor cells from human bone marrow: the influence of aspiration volume. J Bone Joint Surg Am. 1997 Nov;79(11):1699-709.
  2. Fennema EM1, Renard AJ, Leusink A, van Blitterswijk CA, de Boer J. The effect of bone marrow aspiration strategy on the yield and quality of human mesenchymal stem cells. Acta Orthop. 2009 Oct;80(5):618-21. doi: 10.3109/17453670903278241.
  3. Batinić D1, Marusić M, Pavletić Z, Bogdanić V, Uzarević B, Nemet D, Labar B. Relationship between differing volumes of bone marrow aspirates and their cellular composition. Bone Marrow Transplant. 1990 Aug;6(2):103-7.
  4. Centeno CJ, Al-Sayegh H, Bashir J, Goodyear S, Freeman MD. A dose response analysis of a specific bone marrow concentrate treatment protocol for knee osteoarthritis. BMC Musculoskelet Disord. 2015;16:258. Published 2015 Sep 18. doi: 10.1186/s12891-015-0714-z
  5. Pettine KA1, Murphy MB, Suzuki RK, Sand TT. Percutaneous injection of autologous bone marrow concentrate cells significantly reduces lumbar discogenic pain through 12 months. Stem Cells. 2015 Jan;33(1):146-56. doi: 10.1002/stem.1845.
  6. Hernigou P1, Poignard A, Beaujean F, Rouard H. Percutaneous autologous bone-marrow grafting for nonunions. Influence of the number and concentration of progenitor cells. J Bone Joint Surg Am. 2005 Jul;87(7):1430-7.
Chris Centeno, MD is a specialist in regenerative medicine and the new field of Interventional Orthopedics. Centeno pioneered orthopedic stem cell procedures in 2005 and is responsible for a large amount of the published research on stem cell use for orthopedic applications. View Profile

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NOTE: This blog post provides general information to help the reader better understand regenerative medicine, musculoskeletal health, and related subjects. All content provided in this blog, website, or any linked materials, including text, graphics, images, patient profiles, outcomes, and information, are not intended and should not be considered or used as a substitute for medical advice, diagnosis, or treatment. Please always consult with a professional and certified healthcare provider to discuss if a treatment is right for you.