Lineage maintenance

CSF-I is thus one major bioactive factor released by MSS cells which can stimulate Myl-D7. However, it should be noted that stimulation of lineage negative Myl-D7 cells by E.coli-derived recombinant-CSF-1 at equivalent CSF-i concentrations was by far less efficient than CM from MSS cells. Furthermore, the stimulation of lineage negative cells by MSS supernatants was far better than that of L929 supernatants having similar concentrations of CSF-I (data not shown). Thus it is likely that MSS stromal cells produce additional factors that are required for Myl-D7 cell maintenance. 

Basecke, J., Schwieger, M., Griesinger, F., Schiedlmeier, B., Wulf, G., Tmmper, L. and Stocking, C. (2005) AMLl/ETO promotes the maintenance of early hematopoietic progenitors in NOD/SCID mice but does not abrogate their lineage specific differentiation. Leuk Lymphoma 46, 265 272. 

Wolswijk, G. and Noble, M., In vitm studies of the development, maintenance and regeneration of the oligodendrocyte-type-2 astrocyte lineage in the adult central nervous system, in Neumglia, Ketterman, H. and Ransom, B. R., Eds., Oxford University Press, New York, 1995, 149-161. 

The mechanical properties of the capsule must be carefully considered. Not only does the capsule need sufficient strength to resist mechanical failure and rupture but the elasticity of cell substrates have been shown to influence cell behavior. The mechanism by which substrate elasticity influences differentiation of multipotent cells is not clear. A number of recent studies have analyzed this in both two- and three-dimensional (3D) culture systems, - Integrin engagement is thought to be required to transmit the elasticity of the capsule material to the cells inside. Matrix elasticity has been shown to influence the lineage commitment of naive, mesenchymal stem cells. Another important consideration is how the mechanical properties of a capsule impact the transmission of external mechanical forces to the cells. Many cells respond to mechanical loads and this can be necessary for maintenance of phenotype or to guide differentiation. ... 

FAULKS L K, GILLIGAN D M and BEHEREGARAY L B (2010a) Evolution and maintenance of divergent lineages in an endangered freshwater fish, Macquaria australasica. Conservation Genetics, 11,921-934. 

During normal development, the anterior ectoderm is in direct contact with primitive endoderm. It now seems clear that prior to and during gastrulation the anterior visceral endoderm constitutes a signaling center that functions in maintenance of anterior character and head induction (reviewed in ref. 16). Yet, when cultured in isolation with visceral endoderm, anterior ectoderm can be reprogrammed to posterior (hematopoietic and vascular) cell lineages (4). 

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