Mesenchymal stem cells (MSCs) are adult stem cells that help to repair damaged or injured tissue either by differentiating into specialized cells of a tissue system, by helping to recruit progenitor cells or by creating an environment that allows for tissue regeneration.
Throughout the body, billions of specialized cells make up organs like the brain, skin, muscles, tendons, ligaments, joints, and bone. Older cells die off in a degenerative process while new cells are born from stem cells, which have the ability to differentiate into multiple types of other cells, in a regenerative process. However, when tissues are injured, the degenerative process exceeds this regenerative process, resulting in tissue structures becoming weaker, painful and less functional.
In musculoskeletal tissue, pain is often the result of inflammation, which is regulated by pro-inflammatory cytokines. Inflammatory and mitogenic factors try to recruit MSCs and other progenitor cells but non-healing injuries occur when sufficient numbers of progenitor cells or other regenerative building blocks cannot be recruited, leading to injuries not being able to overcome the inflammation stage of healing. Unfortunately, prolonged inflammation in a non-healing injury leads to further cell death and worsening deterioration of the tissue.
Adipose-derived stem cells (ADSCs) are a type of MSC that are obtained from fat cells. The fat cells are taken from the patient in the form of a stromal vascular fraction (SVF), through a minimally invasive procedure where a small volume of fat tissue is obtained in clinic. This fat tissue is then processed mechanically to enrich for MSCs and other beneficial cell types (preadipocytes, endothelial progenitor cells, T cells, B cells, mast cells and adipose tissue macrophages). ADSCs from SVF are combined with PRP to maximize the regenerative potential by harnessing the growth factors present in PRP.
Some of the different cytokines contained in ADSCs with PRP injections are:
- Mitogenic (growth) factors
- Platelet derived growth factor (PDGF), fibroblast growth factor (FGF), hepatocyte growth factor (HGF), insulin-like growth factor 1 & 2 (IGF-1,2), transforming growth factor beta (TGF-?)
- Angiogenic growth factor (which helps promote blood flow and recruitment)
- Vascular endothelial growth factor (VEGF), transforming growth factor beta 1 (TGF-?1)
- Matrix-building proteins
- Fibrinogen, fibronectin, vitronectin
- Anti-inflammatory proteins
- Alpha-2-macroglobulin (A2M), interleukin-1 receptor antagonist protein (IRAP)
These combined ADSCs with PRP injections have anti-inflammatory, anti-microbial, anti-apoptotic and pro-angiogenic properties. This creates a microenvironment conducive to cell recruitment, proliferation and ultimately, tissue regeneration and recovery.