Dr. Joseph Yazdi


Dr. Joseph Yazdi is an engaging, innovating, and experienced neurosurgeon who is committed to providing exceptional outcomes for his patients. He practices a patient centered approach which emphasizes the care of the whole person.

Dr Joseph Yazdi - Stem Cell Therapy

Stem Cells – A Basic Overview

Did you know that stem cells are not new to the field of medicine? For more than 50 years physicians have used them in bone marrow transplants to treat blood cancers¹. They also have therapeutic value for regenerative medicine, but their use is not without significant drawbacks.

Adult stem cells

Doctors harvest these cells from the iliac crest of the hip of adult patients using local or general anesthesia, accessing the bone marrow with a long needle and removing it with a syringe. They then harvest the cells from the bone marrow, purify them and prepare them for donation.

As humans age, the amount of bone marrow – and therefore the number of stem cells it produces – decreases. Since cells from donor bone marrow contain DNA that can cause the patient to reject the donation, doctors prefer to use a patient’s own stem cells. But the patients who need them the most for purposes of anti-inflammation, regeneration and tissue healing tend to be older, and the older the bone marrow, the fewer healthy cells can be harvested from it.

Researchers do not know if there are long-term side effects of stem cell therapy, and the cost of such therapies can be prohibitive. And since insurance companies consider them  experimental in some instances, they aren’t coveredinsurance doesn’t pay for it² ³.

A Nobel Prize-wining discovery in 2006 abated some of these drawbacks.

Embryonic stem cells

Prior to 2006, the best type of stem cell to use in research is the embryonic stem cell, which carries significant ethical issues⁴. Researchers harvest them from embryos created for in vitro fertilization but donated to science for this purpose. Their importance to medical research is that their adult cell counterpart have not been observed changing into as many different types of cells, putting significant limitations on their research and potential uses.

But with the 2006 discovery of lab-created induced pluripotent stem cells, the moral limitations of embryonic stem cell research melted away and scientists are able to explore the full value of stem cell therapy⁵.


IPSCs are created in a laboratory. Researchers believe they are as versatile as their embryonic counterparts but without the ethical concerns. In a short 13 years of research, iPSCs have shown in laboratory and medical study settings to have the potential to help restore vision⁶, increase dopamine receptors in patients with Parkinson’s disease⁷, create new connections and grow nerves in patients with spinal cord injury⁸, produce insulin in diabetes patients⁹, repair muscles damaged by heart attack¹⁰ and even promote hair growth¹¹ ¹².

There is much research to be done before iPSCs make the transition from the laboratory setting to physicians’ offices¹³. In the meantime, regenerative medicine specialists and pain management physicians are looking for similar, albeit safer and more economically reasonable, therapies to combat aging and injury healing. Many of these answers lie in the use of exosomes.

For more information on  stem cell therapy and regenerative medicine contact Dr. Joseph Yazdi at Arch Neurosurgery.

Stem cell – Cells in the body that have the ability to turn into many different types of cells. In certain conditions, researchers can induce them to become tissue- or organ-specific cells. It is their ability to change and regenerate that provides them such potential in the treatment of disease and injury¹⁴.
Adult stem cell– Also known as somatic stem cells (SSC), doctors harvest them from both children and adults. Unlike their embryonic counterparts, there are limits to the types of cells SSCs can differentiate, or change, into. Doctors primarily harvest these cells from the iliac crest of the hip of adult patients. Obtaining the number necessary for therapies can be challenging¹⁵.
Embryonic stem cell – From eggs that have been fertilized for the use of in vitro fertilization but have been donated to science for research. They are pluripotent, which means they can become any type of cell in the human body. Their use has raised significant ethical concerns, leading to the discovery of an alternative – induced pluripotent stem cells.
Induced pluripotent stem cell – Researchers can create them in a laboratory to act like embryonic stem cells with their pluripotent characteristics. Their use is currently limited to the laboratory but they have enormous potential to target cell types that adult stem cells are not able to¹⁶
¹  https://www.cancer.org/treatment/treatments-and-side-effects/treatment-types/stem-cell-transplant/why-stem-cell-transplants-are-used.html
²  https://www.unmc.edu/stemcells/educational-resources/prosandcons.html
³  https://vittana.org/19-advantages-and-disadvantages-of-stem-cell-research
⁴  https://www.worldhealth.net/news/regenerative-potential-induced-pluripotent-stem-cells/⁵  https://www.worldhealth.net/news/regenerative-potential-induced-pluripotent-stem-cells/
⁶  https://www.telegraph.co.uk/news/health/news/12189238/Scientists-use-stem-cells-to-grow-living-lens-in-eye-and-cure-cataracts.html⁷  https://newatlas.com/stem-cells-parkinsons-trials/55690/
⁸  https://newatlas.com/3d-print-neurons-bridge-spinal-cord-injury/55849/⁹  https://newatlas.com/diabetes-stem-cells-insulin-production/58104/
¹⁰ https://newatlas.com/japan-stem-cell-therapy-hearts/54866/¹¹ https://www.cnbc.com/2017/10/13/usc-stem-cell-scientists-developing-a-new-cure-all-for-baldness.html¹² https://newatlas.com/stem-cell-based-treatment-for-baldness-a-step-closer/30720/
¹³ https://www.medicalnewstoday.com/articles/319723.php¹⁴ https://stemcells.nih.gov/info/basics/1.htm
¹⁵ https://www.sciencedaily.com/terms/adult_stem_cell.htm
¹⁶ https://stemcells.nih.gov/info/basics/6.htm

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