Multipotents

Witte, O. N. (1990). Steel locus defines new multipotent growth factor. Cell 63 5-6. 

Based on those results, we concluded that, when cultured on the EGF-His-immobilized surface prepared from a mixed SAM of 10% COOH-thiol, highly enriched NSC populations could be produced in large quantities. Over a 5-day culture on the substrate, cells were expanded 32 times. These expanded cells consisted of 98% nestin+ cells that retained multipotency for differentiation into neuronal and glial lineages. This suggested that selective expansion could be repeated for large-scale production of highly enriched NSC cells. 

Reynolds BA, Tetzlaff W, Weiss SA (1992) A multipotent EGF-responsive striatal embryonic progenitor cell produces neurons and astrocytes. J Neurosci 12 4565 1574... 

Hsieh, J., Aimone, J. B., Kaspar, B. K., Kuwabara, T., Nakashima, K. and Gage, F. H. IGF-I instructs multipotent adult progenitor cells to become oligodendrocytes. J. Cell Biol. 164 111-122, 2004. 

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. 

Figure 2.1. Development of blood cells. The development of blood cells occurs in the bone marrow. All cells arise from the differentiation of pluripotent or multipotent stem cells, which have the capacity for self-renewal, or else can divide into more mature cells types. The morphological features of the mature blood cell types is shown.

It is believed that all blood cells arise from the division and differentiation of multipotent stem cells. These stem cells have considerable capacity for self-renewal by cell division but may also differentiate into progenitor cells of lymphocytic or myeloid lineages (see Fig. 2.1). Experiments with colony-... 

This compound requires metabolic activation by liver microsomes to yield highly mutagenic derivatives in the Ames test204. In addition, IQ is a multipotent animal carcinogen that is metabolized by prostaglandin-H synthase205 and the hepatic cytochrome P-450 system204. 

Stem cells are divided into three different categories totipotent, pluripotent, and multipotent. A description of the genesis of stem cells is shown in Fig. 4.11. 

Pluripotent cells continue to develop, differentiate, and specialize into different cells. They become the specialized stem cells, such as blood, skin, and nerve stem cells. These differentiated stem cells are multipotent that is, they have the potential to produce specialized cells. For example, blood stem cells in bone marrow produce red blood cells, white blood cells, and platelets, but not other types of cells. 

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 umbihcal cords or adult... 

Stem cells and cell therapy is the use of pluripotent and multipotent cells to generate healthy cells and tissues to replace the faulty ones in disease conditions. The main ethical questions are the source of the cells and the possibility of cloning humans. 

The murine hematopoietic stem cell line Myl-D7 spontaneously differentiate along the lymphoid, myeloid and erythroid lineages. Myl-7 cells shows a strict stromal dependence for growth of self-renewing stem cells and express high levels of CSF-1 receptor (Itoh et al., 1996). We used this cell line to analyze the function of CSF-1 in maintaining multipotent cells. In an other attempt to characterize unknown factors that could sustain stem cells we... 

The conditioning of the CD34+ cells as analyzed by colony assays in methylcellulose revealed that membrane-bound SCF mainly supports the maintenance of multipotent and bipotent progenitors. The number of CFU-GM and CFU-GEMM constituted 32% of total colony-forming cells after one week and 52% after two weeks in coculture. In contrast, the proportion of multipotent progenitors in cocultures induced by SI SCF are 4-fold lower after three weeks in culture (Table 2), but the contents of erythroid colonies (BFU-e s) increased 1.5-fold at the same time point. The results indicate that soluble SI SCF promotes more committed cells than membrane-bound SCF. Mature myeloid colonies increased about 1.5-fold in contrast to CFU-C derived from membrane-bound SCF expressing cultures (Friel et al, 2002). 

The cocultivation experiments using CB CD34+ cells thus confirmed our results obtained with the cell line TFl ectopic expression of membrane-bound SCF can substitute for stroma functions like long term maintenance and expansion of multipotent progenitors. 

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