Stem Cells

Stem cells are cells that can renew themselves and turn into other cells (differentiate).  They are the “Repairmen of the Body”.  They live inside all of us in various tissues, ready to repair damage to our tissues as it occurs.  As we age or have severe injuries, we may not generate enough of these cells to the site to fully repair the area.  There remains ethical debate about stem cells, but that is based on fetal or embryonic cell lines, not the adult stem cells that are derived from the patient's own body.

For orthopedic applications, two main types of Mesenchymal Stem Cells (MSC’s) have been used, bone marrow derived and adipose (fat) derived.  Bone marrow stem cells are taken via a needle through a bone marrow aspirate from the hip bone.  The second type of MSC is derived from fat tissue (adipose), which can be obtained via liposuction. 

Bone marrow derived MSC’s produce cartilage repair, bone repair, and soft-tissue repair. This makes sense, as they perform this function naturally every day.  For example, if you break a bone, these bone marrow MSC’s help mend that bone.  There are surgical techniques including "micro-fracture" that can repair small amounts of knee cartilage damage; it is bone marrow MSC’s that are released that do the job. 

There are many types of adult stem cells.  The most common is known as a hematopoetic stem cell (HSC-CD 34+).  While these are easy to obtain from IV blood or bone marrow and are very plentiful, outside of a handful of cardiac and vascular applications, they are not well studied as being effective in treating a broad range of disease.  Despite this, the vast majority of what you see being billed as “stem cells” (where the cells are injected the same day as collected from bone marrow or blood) are these less useful cells.  The type of adult stem cell that is most often seen in research as being associated with tissue repair is a mesenchymal stem cell (MSC).  MSC’s can’t generally be harvested from blood, but they can be obtained in moderate numbers at the bedside, processed, and re-injected in the same day. 

The future of stem cell regenerative techniques will likely require that MSC’s be reproduced by culture expansion.  This means that the cells are grown in culture to higher numbers before being used for treatment.  This usually takes 10-18 days.  There are regulatory (governmental) hurdles to using your own stem cells for healing your own body that are being addressed by the American Stem Cell Therapy Association. Please read more at www.stemcelldocs.org.