I participated in a study at the large medical center associated with our university system. They collected and compared stem cells from two places (bone marrow from my breast bone and pelvic bone). But I never heard the results of the study. What kind of research is being done with bone marrow stem cells?

A great deal of research is focused now on tissue regeneration for soft tissue and bone repair in humans. Stem cells from the person’s own bone marrow have two major advantages: the patient does not experience cell rejection and this source of stem cells avoids the controversy over the use of embryonic stem cells. Stem cells are useful because they can divide and develop into any type of cell in the body (including bone or cartilage).

Surgeons can remove or aspirate stem cells from the sternum (breast bone), vertebrae (spinal bones), and iliac crest (top of the pelvic bones). Studies are ongoing to investigate the effect(s) of removing stem cells from these areas and comparing results among the various harvest sites.

In a recent study from Italy, use of stem cells were compared between the anterior iliac crest and posterior iliac crest. Twenty-two adult donors (ages 18 to 72) participated in that particular study. A total of 20 mL of bone marrow was withdrawn using a collecting needle (skin puncture) in three places along the iliac crest.

The cells were taken to a lab and processed. The different types of cells were separated and counted in the first step of the process. Then the cells were prepared in such a way to allow them to replicate (grow and multiply) over a period of 14 days. The total number of cells was recounted with a particular focus on one type called connective-tissue progenitor cells. These cells are especially useful for repair of connective tissue.

The results of this study showed that bone marrow harvest of cells that become connective-tissue progenitor cells was better from the posterior iliac crest. In fact, there were 1.6 times more of these cells in the posterior compared with the anterior iliac crest. The recommendation made as a result of this study was for harvest of stem cells from the posterior iliac crest for bone repair.

There are many, many factors that can affect the total yield of the different cells produced from stem cells. Site of harvest in only one. The age and sex of the patient may make a difference. And although 14 days was the time period used in this study, it’s possible that other time periods would yield different results. The study you participated in could have been exploring any one of these factors. You can probably contact the study coordinator and find out more about the goal and results.