Umbilical cord blood, Wharton's jelly within the umbilical cord, bone marrow, adipose tissue, dental pulp, skin, connective tissue are very rich in mesenchymal stem cells.
Today, adipose tissue is the most commonly preferred source of mesenchymal stem cells because of its ease of derivation. The studies have shown that mesenchymal stem cells can differentiate into osteoblast, myoblast, adipocyte, chondrocyte cells. Moreover, the density of mesenchymal stem cell has been shown to be much higher in adipose tissue than in bone marrow. Nowadays, mesenchymal stem cells originating from adipose tissue or bone marrow are widely used especially in orthopedics and plastic surgery branches. Stem cells can be proliferated in culture medium using some chemical stimulants and factors. However, it is not yet clear what genotypic and biological effects this proliferation procedure has on those stem cells. The main concern here is whether it results in malignant transformations.
As surface markers, CD105, CD73, CD90 are positive.
Even if embryogenic stem cells are today theoretically considered in regenerative medicine practices, they are not used in human treatments due to ethical reasons. Adult stem cells of the individual started to be used in the treatment of some diseases (such as the elimination of scars and burn marks) in the clinic because of the absence of ethical barriers and not causing immunological problems. Adult stem cells are present in almost all tissues with a certain density. These are mostly silent (dormant) cells in sleep and proliferate or differentiate according to the need. In brief, adult stem cells are undifferentiated cells within differentiated tissues. And they serve only as backup cells, showing differentiation if needed. It is possible to come across stem cells at almost every point in the human body. Adult stem cells residing in the tissue are multipotent mesenchymal stem cells. In the bone marrow, both hemopoietic and mesenchymal stem cells coexist
Mesenchymal Stem Cells from Bone Marrow
Deriving mesenchymal stem cells from bone marrow is generally an invasive, time-consuming, and more expensive method. However, the number of stem cells to be derived from bone marrow is more limited compared to tissues. In this case, there was a need for a stem cell source that could differentiate into the desired cell that does not much impair patient comfort, and the most ideal source has been suggested adipose tissue. It has been shown that adipose derived mesenchymal stem cells (ADSCs) have the potential to differentiate as much as bone marrow derived cells. Moreover, it is of great advantage that a greater number of stem cells can be derived.