The stem cell niche is the dynamic microenvironment where stem cells reside. Inside these niches, the cells may remain undifferentiated, undergo high self-renewal, or become lineage-specific progenitors. Stem cells coexist with other niche cells, such as stromal cells. They also interact closely with the ECM. Cell-cell and cell-matrix communication occur via adhesion molecules or soluble factors that signal the stem cells and determine their fate. Stromal cells also provide survival signals to...

Stem cell therapy is a method used in regenerative medicine to repair and restore function to damaged tissues and organs. Stem cells have the potential to proliferate and differentiate into various tissue types, making them ideal candidates for tissue regeneration. For example, hematopoietic stem cell transplants are commonly used in blood cancer treatment to replenish damaged bone marrow and restore healthy blood cells.
Types of Stem Cells used in Stem Cell Therapy
The two main cell...

A hair follicle or HF is a small part of the skin that produces the hair shaft. Paul Gerson Unna was the first to observe a bulge in the human hair follicle's outer root sheath (ORS). The bulge is present between the sebaceous gland and the arrector pili muscle and is the niche for hair follicle stem cells (HFSCs). The bulge is also a niche for melanocyte stem cells, and their loss results in graying of hair. The HFSCs express Sox9 and Lhx2, which help them maintain stemness and prevent...

Stem cells are undifferentiated cells with extensive self-renewal properties that help them maintain their population during the fetal and adult stages of life. They can specialize in all cell types of the human body. However, their differential potential may vary and can be classified into five types. Stem cells can be (1) Totipotent, (2) Pluripotent, (3) Multipotent, (4) Oligopotent, and (5) Unipotent. Each stem cell has a specific origin; the fertilized egg or zygote is a totipotent cell and...

Embryonic stem (ES) cells are undifferentiated pluripotent cells, meaning they can produce any cell type in the body. This gives them tremendous potential in science and medicine since they can generate specific cell types for use in research or to replace body cells lost due to damage or disease.

The hematopoietic stem cells or HSCs are multipotent, meaning they can differentiate and give rise to all blood and immune cells. HSCs are maintained in the quiescent stage until an external stimulus initiates their differentiation. The multipotent HSCs exist as two heterogeneous populations, long-term repopulating cells (LTRC) and short-term repopulating cells (STRC). The two HSC populations have different surface markers or receptors and are classified based on quiescence and long-term...