Cells for New life
English

Types of Stem Cells

Adult Mesenchimal Stem Cells

Adult Mesenchymal Cells

Introduction:

Mesenchymal Stem Cells (MSCs) are non-hematopoietic stem cells, found in the bone marrow and most connective tissues of the body.  Initially, about 130 years ago a German pathologist Cohneim proposed that bone marrow can be the source of fibroblasts contributing to wound healing in numerous peripheral tissues.  Later, MSCs were identified as colony-forming unit-fibroblasts (CFU-Fs) by Friedenstein and colleagues in 1970. It was demonstrated that each bone marrow donor displays a specific frequency of CFU-f, which is dependent on the age and health of the donor. MSCs are important part of tissue engineering and have huge therapeutic applications due to their ability to differentiate into mesenchymal tissues like bone, cartilage, adipose tissue and muscle (Figure 1). Additionally, MSCs, themselves, secrete a broad spectrum of bioactive macromolecules that are both immunoregulatory and serve to structure regenerative microenvironments in fields of tissue injury and it is the basis of “Regenerative medicine”. Hence, these are called multipotent. These genetically engineered molecules are immunosuppressive, especially for T-cells and, so the allogeneic MSCs can be considered for therapeutic use. Existence of MSCs is not only restricted to bone marrow, as these can also be traced in tissues like fat, umbilical cord blood, amniotic fluid, placenta, dental pulp, tendons, synovial membrane and skeletal muscles etc. 

Usually, MSCs are isolated from the bone marrow, as well as from other tissues like adipose, muscle, bone, and tendon. However, according to a recent study, MSCs also have been isolated from other non-mesodermal tissues like brain, spleen, liver, kidney, lung, thymus, and pancreas.  However, one of the another study reports that murine MSCs can be isolated from fresh cells of the heart, liver, kidney, thymus, ovary, dermis, and lung based on CD45/Sca-1+/Thy-1 phenotype.