Stem cells compartment

AML represents a group of disorders in which both failure to differentiate and overproliferation in the stem cell compartment produce an overabundance of nonfunctional cells termed myeloblasts. While the specific cause for this biologic abnormality is unknown, an understanding of the genetic influence of leukemia is leading to a wide variety of targeted therapies.9... 

Patients who present with symptomatic disease will be started on therapy. Two regimens used are VAD and melphalan and prednisone (MP). VAD like chemotherapy regimens are used most often in transplant candidates because it avoids the alkylating agent melphalan, thus minimizing damage to the stem cell compartment. These two regimens produce equivalent response rates of approximately 50% to 70% in previously untreated patients with myeloma (see Table 93-4).35>36... 

Mazurier F, Gan O, McKenzie J, Doedens M, Dick J. Lentivector-mediated clonal tracking reveals intrinsic heterogeneity in the human hematopoietic stem cell compartment and culture-induced stem cell impairment. Blood. 2004 103 545-552. 

McKenzie JL, Gan 01, Doedens M, Wang JC, Dick JE. Individual stem cells with highly variable proliferation and self renewal properties comprise the human hematopoietic stem cell compartment. Nat Inununol. 2006 7 1225 1233. 

Cord blood has long been used as a source of MSCs for bone marrow transplantation. The stem cell compartment is more abundant and less mature in cord blood than in bone marrow. Moreover, MSCs in cord blood have a higher proliferative potential because of their extended lifespan and longer telomeres [91-94]. Not only can cord-blood MSCs be harvested without morbidity to the donor, but they also display a robust in vitro capacity for directable or spontaneous differentiation into mesodermal, endodermal, and ectodermal cell fates. Cord-blood MSCs are CD45 and HLA-II and can be expanded without losing their pluripotency. Therefore, cord blood is also undergoing preclinical evaluation as a possible easily accessible source of multipotent cells. 

Wright, E. G. and Pragnell, I. B. (1992) The stem cell compartment Assays and negative regulators. Current Topics Microbiol. Immunol. 177, 137-149. 

Seidel HJ, Barthel E, Zinser D. 1989a. The hematopoietic stem cell compartments in mice during and after long-term inhalation of three doses of benzene. Exp Hematol 17 300-303. 

Bradford G B, Williams B, Rossi R, et al. (1997). Quiescence, cycling, and turnover in the primitive hematopoietic stem cell compartment. Exp. Hematol. 25 445-453. Cheshier S H, Morrison S J, Liao X, et al. (1999). In vivo proliferation and cell cycle kinetics of long-term self-renewing hematopoietic stem cells. Proc. Natl. Acad. Sci. USA. 96 3120-3125. 

Peacock CD, Wang Q, Gesell GS et al. (2007) Hedgehog signaling maintains a tumor stem cell compartment in multiple myeloma. Proc Natl Acad Sci USA 104 4048 4053... 

In multicellular hosts, the stem cell compartments preserved most of the faculties of the ancient RNA/DNA complex. The healthy stem cells RNA/DNA complex serves its multicellular host in its ontogenesis (in fertized egg cells, in the larvae, pupae and nymphs, or in the embryo). The pluripotent and asymmetrically dividing... 

The stem cell practices self-preservation by dividing asymmetrically in almost unlimited numbers of divisions, with the release of a somatic daughter cell on each occasion. Since stem cells are singularly distributed in the parenchyma, they must build up that daughter cell within their nucleus and cytoplasm from nutrients received by difiiision unless, there are special stem cell compartments (in the Lieberkuhn ciypts in the gut), where stem cells may receive blood supply. In contrast, the differentiated somatic cells of the multicellular hosts are allowed only a limited number of cell divisions. The somatic cells of the multicellular host are instmeted to leave their chromosome ends uncapped after each mitosis. This is in contrast to many extant free-living, or parasitic unicellular life forms, which diligently recap their chromosomal ends after each of their divisions Trypanosoma... 

Schlotzer-Schrehardt U, Dietrich T, et al. Characterization of extracellular matrix components in the limbal epithelial stem cell compartment. Exp Eye Res December 2007 85(6) 845-60. 

Kubanek, B., Bock, O., Heit, W., Bock, E., Harriss, E.B. Size and proliferation of stem cell compartments in mice after depression of erythropoiesis. In Haemopoietic stem cells. Ciba Found. Symp. 13, p. 243-255. Amsterdam Associated Scientific Publishers 1973... 

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