The MSC System
The Mesenchymal Stem Cell (MSC) System
Mesenchymal Stem Cells or Mesenchymal Progenitor Cells (MPC) have the potential for producing multiple types of tissue including:
- Hematopoietic stroma or supporting cells
- Osteocytes
- Chrondrocytes
- Adipocytes
- Skeletal, smooth and cardiac muscle
- Astrocytes
- Oligodendrocytes
- Neurons
Hematopoietic supporting cells or stromal cells were recognized as a distinct heterogenous population during long-term culture of hematopoietic cells. However, the “hematopoietic inductive microenvironment”, postulated by Trentin (1971), is considered to consist of the hematopoietic stroma. In addition, the “stem cell niche”, first suggested by Schofield (1978) contains non-hematopoietic derived fibroblasts, endothelial cells, reticulum cells and fat cells, as well as macrophages. In accordance with the nomenclature used for hematopoietic stem, progenitor and precursor cells, a clonal population of fibroblastoid-like MSC or their immediate progeny was designated the colony-forming unit or cell - fibroblast (CFU-F or CFC-F) by Friedenstein and coworkers (1971). There are few, if any distinctive characteristics of MSC. Rather, several markers have been used that together, exclude other cell types and, in turn, define the MSC population.
