![]() | This article may be too technical for most readers to understand.(October 2021) |
KSL cells in cell biology are an early form of mouse/murine hematopoietic stem cells. Characteristics are Kit (+), Sca-1 (+) and Lin (-). HSCs [Hematopoietic stem cells] in murine cultures show phenotypic markers as being CD34-, CD150+, and Flt3- for LTR [long-term reconstitution]. These phenotypic markers are used when purifying hematopoietic stem cells from the many other differentiated cells in the bone marrow.
Kit (CD117) is the receptor of Stem Cell Factor. Sca-1 is a murine hematopoietic stem cell antigen. Lin is a series of lineage marker antigens that identify mature murine blood cells.
Hematopoietic stem cells are of interest because of their ability to self-renew and differentiate into every types of blood cell. Transplantation of these cells in the bone marrow can be used to treat leukemia and other diseases of the blood and immune system. Murine/mouse cells lines are used as a model to research treatments before they are tested on humans.
Hematopoietic stem cell (HSC) heterogeneity and hierarchy are a current topic of interest, having major implications for clinical HSC transplantation and basic research on human HSCs. It was long believed that the most primitive HSCs in mammals, including mice and humans, were CD34 antigen positive (CD34+). However, 2 decades ago, it was reported that murine long-term multilineage reconstituting HSCs were lineage marker negative (Lin-, i.e., c-kit+Sca-1+CD34low/-), known as CD34low/- KSL cells. In contrast, human CD34- HSCs, a counterpart of murine CD34low/- KSL cells, were hard to identify for a long time mainly because of their rarity.