Whether your adult mesenchymal stem cells come from bone marrow or from fat probably does not make a difference in terms of clinical results. Although some centers claim that bone marrow derived cells are superior to fat derived cells, there is no evidence to substantiate that. The fact that there are many more studies on bone marrow cells does not prove clinical superiority but merely supports the obvious fact that fat derived cells are based on more recent discoveries and although evidence is accumulating, there are far fewer studies using these cells. It is important that one is not mislead by the word “bone” in bone marrow, possible implying that since this is an “orthopedic source” it must be better for treating orthopedic conditions such as cartilage regeneration. In fact, the bone marrow is part of the reticulo-endothelial system and just happens to be found in the center of bone. As described in a pending publication by Michalek showing excellent safety and efficacy in 1128 patients who had large joint injections of SVF; “At this point, we should also clarify the terminology regarding the source of SVF cells. In the vast majority of scientific publications only the term adipose tissue is used, but the true source of SVF cells is not the adipose part but only the stromal (ie. loose connective tissue) part of the fat obtained typically by liposuction. Histologically, the fat lobules are surrounded by a loose connective tissue and the SVF cells reside in the loose connective tissue that also home capillaries and small vessels. Stroma is a broadly used term for the loose connective tissue that contains mesenchymal stem cells and other cells like fibroblasts, macrophages, adipocytes, mast cells and leukocytes. Synovia of articulated joints is also intimately associated with the loose connective tissue which is homologous to the loose connective tissue of the adipose tissue. Thus, in our clinical study we were aiming to enrich the population of stem and other regenerative cells in a close proximity to damaged cartilage.”

Clearly, both marrow and stromal derived stem cells are effective and have the potential to differentiate into mature functional cartilage. For many disease types, adipose derived cells are actually showing superiority to bone marrow derived cells due to the profound anti-inflammatory effects of SVF. This may be related to the well documented qualitative and quantitative attrition in bone marrow stem cell counts related to age and chronic illness. Another important advantage of using fat derived cells is their abundance and therefore there is no need for laboratory expansion by culturing. Also, the ease of removing fat from under the skin using a mini-liposuction under local anesthetic is much less invasive and painful than undergoing bone marrow aspiration.