Platelet Rich Plasma, Bone Marrow Concentrate and Adipose Derived Cells: Quantitative Analysis and Quality Control—What Does It All Mean?

Autologous treatments like platelet-rich plasma (PRP), bone marrow concentrate (BMC) and adipose tissue-derived therapies including stromal vascular fraction (SVF) and microfragmented adipose tissue (MFAT) are comprised of a complex set of cell types with cell numbers that vary from patient to patient. Although progenitor cells like mesenchymal stromal cells (MSCs) are found in BMC, SVF and MFAT, establishing a therapeutic dose for these types of autologous preparations remains problematic. However, it is important to attempt to quantify the biological contents of these preparations, and the technical approaches for doing so are reviewed herein. Ideally, a quantitative assessment of PRP, BMC, SVF and MFAT not only would include an assessment of the type and frequency of cells, but also would include quantifying the cytokine content of platelets, exosomes present in the PRP and BMC plasma and the levels of critical proteins like alpha-2-Macroglobulin. However, the technology required for this degree of analysis is well beyond the clinic or office setting. Several examples of clinical studies in which a quantitative assessment of the number of MSCs present in BMC, or the number of platelets present in PRP are reviewed with a focus on how the quantitative analysis points to better therapeutic outcomes.