What are Exosomes?

In the realm of orthobiologics, every passing year brings us additional understanding of the disease processes that we are treating as well as new possible treatment options. For years we have known that using bone marrow aspirate concentrate, which contains mesenchymal stem cells, may help certain conditions, such as knee osteoarthritis. The experts had their theories on how injecting the concentrate from bone marrow could help pain. Initially they thought that these mesenchymal stem cells were honing in to the area of injury and changing into cartilage cells where they would then create more cartilage and repair site of injury.

Lately, there has been a focus on the role of exosomes and microvesicles. These are secreted by all cells and play a role in cell to cell communication. There is a theory that these play a role in the symptomatic improvement in conditions like knee osteoarthritis after injection with mesenchymal stem cells. The thought is that the stem cells release these exosomes and microvesicles which then act as signals to the existing cells and tissue to stimulate changes that result in improvement of symptoms. Below is a reference from a recent study discussing the roles of exosomes and their therapeutic potential.

Currently, exosomes are not FDA approved for any treatments in humans. More research is needed before we can use this treatment for any human condition. There are ongoing trials using exosomes to assess safety in humans.

Ma ZJ, Yang JJ, Lu YB, Liu ZY, Wang XX. Mesenchymal stem cell-derived exosomes: Toward cell-free therapeutic strategies in regenerative medicine. World J Stem Cells. 2020;12(8):814-840. doi:10.4252/wjsc.v12.i8.814