Hello, blog readers. If you are reading this blog, then you should know that we are cycling through different posters each week. And if you are reading this blog, you should also know that you have excellent judgement in selecting online sources of information regarding cell therapies.

My name is Richard Suzuki, and I’m one of the Ph.D.s here at Celling. I’ve done guest blogs, and this time I would like to address a recurring question that is brought up in the autologous cell therapy field. 

This blog has already discussed at length the fact that mesenchymal stem cells (MSCs) can be concentrated from a patient’s iliac crest bone marrow to provide treatment. In spite of that, surgeons often ask if they can use autologous cell therapy to treat older patients. There is a concern because it has been documented that the number stem cells in our bone marrow decreases with age (1, 2).

This does make sense. Everything about our bodies save wisdom seems to decrease with age, but this observation has been unreasonably extrapolated into a belief that older patients do not have enough stem cells to warrant any attempt of aspiration and concentration of their bone marrow. My colleagues have even heard claims that older patients do not have any stem cells in their bone marrow at all. Apart from the fact that a person would die if there were no stem cells in their marrow, the complete disappearance of stem cells in the marrow is not backed by data in the literature.

The simple truth is that the natural decrease of MSC population in the marrow of older patients does not preclude autologous cell treatment as an option. Dr. Phillipe Hernigou has been mentioned frequently enough in this blog that he should need no introduction, and he will soon be publishing data comparing traditional, bilateral total knee arthroplasty (TKA) with subchondral injection of concentrated, autologous bone marrow. The study is particularly interesting because it examined a patient population in which all patients were older than 85 years. Patients were also matched in their demographic and radiographic scores.

Dr. Hernigou extracted a relatively large volume (200mL) of bone marrow from each patient’s iliac crest, and he that showed that through concentration one can achieve significant numbers of MSCs. He observed over an average of 3500 MSCs /mL in the concentrate from these older patients. Clearly, there are indeed stem cells in the marrow of older patients and through concentration, the cells can be used for treatments.

The average follow-up for the study patients was 4-14 years with an average of 6 years.  Patients treated with the concentrated marrow injections showed similar improvement to those treated with total knee arthroplasty. Treatment with bone marrow concentrate injections also showed advantages to TKA in categories such as length of hospital stay, length of anticoagulation therapy and other outcome measures. Dr. Hernigou was kind enough to allow us to mention his results here, but to see more details you’ll have to wait until the study is published. We’ll be certain to announce it here, so you’ll be the first to know.

Dr. Hernigou has also presented the way in which he adapts to the decrease of MSCs in older patients by aspirating larger amounts of marrow while using his small-volume syringe technique, which optimizes MSC collection. Collecting a larger volume of bone marrow allows more total MSCs to be present when the marrow is concentrated. We’ll discuss this in a later blog.