Multipotent adult stem cells

Toma, J. G., Akhavan, M., Fernandes, K. J. et al. Isolation of multipotent adult stem cells from the dermis of mammalian skin. Nat. Cell Biol. 3 778-784,2001. 

Nakayama and Inoue 2006), and cardiomyocytes (Wobus et al. 1991, Maltsev et al. 1994, Boheler et al. 2002, Fijnvandraat et al. 2003). Although more dilFerentiated cells, such as multipotent adult stem cells, are already partially committed to a certain lineage and therefore may be easier to coax toward a desired phenotype, the proliferative capacity also generally decreases rather dramatically as cells differentiate. In addition, more differentiated cells ohen do not survive when transplanted in vivo, and necessitate tissue-specific stromal cells. Although current methods for ESC differentiation often result in heterogeneous populations, there is promise for the creation of complex tissues comprising multiple cell types. 

The ability of adult stem cells to become something other than what they were destined to be is controversial. One team of scientists has reported that a particularly promising adult stem cell, isolated from bone marrow and called a multipotent adult progenitor cell (MAPC), appears able to develop into many different kinds of specialized cells in the laboratory. Other scientists have not been able to reproduce these results. Additionally, scientists have reported that stem cells found in fat can become muscle cells, nerve cells, or even pancreas cells able to make insulin, under the right laboratory conditions. 

Laywell, E.D., Rakic, P., Kukekov, V.G., Holland, E.C., Steindler, D.A. (2000). Identification of a multipotent astrocytic stem cell in the immature and adult mouse brain. Proc Natl AcadSci, USA 97, 13883-8. 

Adult Stem Cell Specific niches in adult tissue (Location varies for each tissue/organ) Infinite Multipotent (Can differentiate into most cells of the tissue in which they reside. Also, they may have plastisity, which allows them to differentiated into cells of other tissues)... 

There are two general avenues for stem cell research pluripotent and multipotent stem cells. Pluripotent stem cells are obtained by two methods. One method is to harvest the clusters of cells from the blastocysts of human embryos. Another method is the isolation of pluripotent cells from fetuses in terminated pregnancies. Multipotent stem cells are derived from umbilical cords or adult stem cells. However, because of the specialization of these cells, their potential to develop into a myriad of different cells is limited. 

Mesenchymal stem cells are another group of adult stem cells that have been suggested as potential donor cells (see Part I, Chapter 13). These cells are accessible from the bone marrow and peripheral blood, allow autologous transplantation, may be multipotent, and can also differentiate into specialized tissues, including possibly cardiomyocytes, endothelial cells. 

Plasticity of HSCs. The hematopoietic tissues such as the bone marrow and peripheral blood have heterogeneous stem cell populations, including hematopoietic stem cells, mesenchymal stem cells, multipotent adult progenitor cells, and endothelial precursor cells. HSCs have been widely used to study the plasticity of adult stem cells [23]. Stem cell plasticity can be defined as a unique property of tissue-specific adult stem cells. Approximately more than 80% of studies reporting... 

Multipotent Adult Progenitor Cells (MAPCs) MAPCs are bone marrow-derived stem cells with an extensive in vitro expansion ability, more than 80 population doublings, as well as a capacity to differentiate in vivo and in vitro into tissue cells of all three germinal layers ectoderm, mesoderm, and endoderm. These cells have been isolated from three different species, including mouse, rat, and human [27]. 

Reyes M, Verfaillie C M (2001). Characterization of multipotent adult progenitor cells, a subpopulation of mesenchymal stem cells. Ann. NY Acad. Sci. 938 231-233, discussion 233-235. 

Weiss S, Dunne C, Hewson J, et al. (1996). Multipotent CNS stem cells are present in the adult mammalian spinal cord and ventricular neuroaxis. J. Neurosci. 16 7599-... 

Stem cells, whether derived from embryos, fetuses, or adults, can be simply defined as progeny of cells that are capable of differentiating into different lineages [152], Embryonic stem cells (ESCs) are isolated from the inner cell mass of blastocysts and have the ability to be cultured and maintained in an undifferentiated and pluripotent state, and directed to differentiate into all specific cell types [153,154], A variety of adult stem cells (often referred as progenitor or multipotent cells), including bone marrow-derived mesenchymal stem cells (MSCs), hematopoietic stem cells (HSCs), adipose-derived stem cells (ADSCs), and neutral stem cells (NSCs), have been found more committed but less pluripotent than ESCs. 

One of the early sources of adult stem cells to be investigated was bone marrow. A subset of multipotent progenitor cells was found to reside in the bone marrow niche and could be induced to differentiate down specific mesenchymal lineages [94], The bone marrow aspirate is collected from the iliac crest, followed by selection for plastic-adherent cells. 

Induced pluripotent stem cells are the adult cells that have been transformed into pluripotent stem cells through programming. Among adult stem cells, Mesenchymal stem cell is widely used as a multipotent source. Mesenchymal stem cell is derived from bone marrow stroma and can differentiate into a variety of cell types in vitro. Other sources of adult stem cells include the amniotic fluid and placental derived stem cells [29, 30]. 

De Bari, C., Dell accio, F., Tylzanowski, R, and Luyten, F. P. 2001. Multipotent mesenchymal stem cells from adult human synovial membrane. Arthritis Rheum, 44,1928-42. 

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