Stem Cell Therapy

What are stem cells?

Stem cells are the body’s master cells, the origin of most all cell types in the body. Stem cells have the potential to multiply and develop into a variety of cell types from skin and bone to neurons in the brain. There are three main types of stem cells, adult stem cells (ASCs), also known as somatic stem cells, which are derived from adult human tissue such as bone, fat also known as adipose, etc., embryonic stem cells (ESCs) derived from embryos, and induced pluripotent stem cells (iPSCs), modified cells derived from adult stem cells. Stem cells are often categorized by their cell type potential. Pluripotent stem cells, typically derived from embryonic or umbilical cord tissue, can develop into virtually any cell type in the body. Multipotent stem cells, typically derived from bone, adipose and other tissue, can develop into a smaller number of cell types. Unlike other cells in the body, stem cells are able to transform into a variety of cell types because they are “unspecialized” – they have not yet been instructed as to what type of cell they should become. Once these stem cells become specialized, they begin to function as that specialized cell type.

What do stem cells do? How do they work?

Stem cells are unspecialized cells found in the human body that have the potential to develop into a variety of different cell types. Stem cells also act as an internal repair system, replacing damaged and dysfunctional cells and restoring function. In addition to the repair and replace mechanism of action, stem cells also have anti-inflammatory, immune modulating and anti-microbial properties and contain numerous growth factors. These properties often result in regeneration of healthy tissue, reduced pain and inflammation, and improvement of cellular function. Considering these properties, stem cell therapy is being actively researched for treating numerous chronic and degenerative diseases. For more detailed information regarding the mechanisms of action of stem cells please see “Stem Cell Mechanisms of Action.”

How are stem cells administered?

Stem cells can be administered in a variety of different ways depending on the condition being treated. Common routes of administration include intravenous (into veins), intra-articular (into joints) and intrathecal (into spinal cord). For example, stem cells are injected locally into affected joints and soft tissue for most orthopedic conditions such as osteoarthritis or ligament/tendon injuries. A local anesthetic is used prior the procedure to reduce injection related pain. Other methods of stem cell administration including local injections into the eye, heart, brain and other organs are typically reserved for hospital or surgical suite settings as they are more invasive and have higher risk for complications.

Where do stem cells come from?

Stem cells were first discovered in mouse embryo and bone marrow. As research progressed researchers found stem cells in human embryos. However, due to the controversy of sourcing the human embryos, researchers had to look elsewhere. Over the course of many years researchers found stem cells in a variety of human tissues including bone marrow, fat tissue also known as adipose tissue, umbilical cord tissue, placental tissue, dental tissue and even urine. Patients receiving stem cell therapy either have their own cells collected and administered, which is called autologous stem cell therapy or have manufactured or donated stem cells administered, which is called allogenic stem cell therapy. Both autologous and allogenic stem cells have been shown to be safe.

How are stem cells harvested?

Patients may receive autologous stem cell therapy where stem cells are harvested from their own tissue or receive allogenic stem cell therapy where stem cells are used from manufactured or donor tissue. Autologous stem cell therapy requires an invasive surgical procedure that is typically expensive and can be very painful. Bone marrow stem cells are collected by drilling into the posterior iliac crest, a region of pelvic bone near the low back, and removing a sample of bone marrow. This procedure can be very painful with pain lasting days or weeks, and often leaves a sizable scar. Adipose stem cells are collected by making one or two small incisions in the abdominal flanks then a liposuction device is used to remove samples of fat tissue. Due to the invasiveness and cost, autologous stem cell therapy is gradually being replaced by allogenic stem cell therapy in the clinical setting. Allogenic stem cell therapy does not require the patient to undergo invasive harvesting procedures prior to treatment. Many companies in the US offer allogenic stem cells which are typically derived from umbilical or placental tissue. These products are required by US law to follow strict safety regulations and manufacturing processes. The stem cells are typically verified and characterized in the laboratory, screened for containments, bacteria, viruses, etc., and sterilized to stringent standards to ensure safety without diminishing their effectiveness.

Aren’t stem cells controversial?

Stem cell therapy became controversial when researchers were harvesting stem cells from human embryos. This type of stem cell, referred to as embryonic stem cell, is rarely used in treatment due to both controversial and ethical dilemmas surrounding the source of these cells. The less controversial and safer type of stem cell is called somatic stem cell or adult stem cell. These cells can be collected from a variety of adult human tissues including bone marrow, fat tissue also known as adipose tissue, umbilical cord tissue, placental tissue and others.

Is there research on stem cell therapy?

Yes. There is a significant amount of published research demonstrating the safety and efficacy of stem cell therapy in a number of conditions. Please see our Research Archive for more detailed information regarding published research.

Is stem cell therapy safe?

The safety and tolerability of stem cell therapy has been clearly demonstrated in numerous published studies large numbers of patients treated for various different conditions. Commonly reported adverse events include headache, local injection site irritation and pain, fever, and others which are usually short lived and do not require additional treatment. Infection is a serious complication and is always a risk with any type of injection therapy. However, using universal administration safety protocols this risk is significantly minimized, if not eliminated. Serious short or long term adverse reactions to stem cell therapy such as blindness, cancer, blot clots, stroke, death, etc., have been reported, but are exceedingly rare. Factors that affect safety and tolerability include individual patient’s health, source of allogenic stem cell products, stem cell dose, frequency of treatment and method of administration (IE. Injections into the eye, brain and spinal cord are higher risk for adverse effects compared to intravenous or local joint injections). For more information on the safety of stem cell therapy, please see our Safety Research Archive.

Will the joint and soft tissue injections hurt?

For orthopedic conditions, stem cells can be injected into various joints and soft tissues such as tendons and ligaments for healing and repair of dysfunctional and or injured tissue. Such injections do not require local anesthesia, take only a matter of seconds and are relatively pain free. Many patients have compared the injection to that of a cortisone injection. The safety and efficacy of stem cell injections for orthopedic conditions has been reported in numerous studies. For more detailed information please see our Safety Research Archive and Orthopedic Research Archive.

Serious and severe adverse reactions to orthopedic stem cell injections are exceedingly rare. Common, self-limiting side effects are pain and swelling at injection site for 12-72 hours post treatment. These are alleviated by short term use of ice, pain relievers and other recommendations by your doctor. Infection is always a risk with any type of injection therapy, however using universal safety protocols this risk is significantly minimized if not eliminated.

How many stem cell treatments will I need?

Each patient is unique with their own factors affecting their response to therapy and the need for additional treatment. For many a single treatment can provide significant, long lasting results, however others may need to repeat treatment over time usually every 3 to 12 months or as needed for optimal effects. Your doctor will assess your response to treatment in a follow up consultation and discuss additional treatment as needed.

How long will it take to see results?

Each patient is unique with their own factors affecting their response to therapy. There is no guarantee of what the results will be or the time it will take to see results. Some patients have reported immediate results while others have reported results within 3-6 months after treatment. Some patients who have received treatment only minimally improved or did not improve at all.

Will my health insurance cover this?

Like many treatments in regenerative medicine, stem cell therapy is considered elective or experimental is not covered by insurance companies.

Brought to you by:

Ahvie Herskowitz, MD, President of ACAM
Director of Anatara Medicine
Clinical Professor of Medicine at UC San Francisco (2014)
(Read Dr. Herskowitz’s Bio Here)

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