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Asymmetric division and lineage commitment at the level of hematopoietic stem cells: inference from differentiation in daughter cell and granddaughter cell pairs.

Takano H, Ema H, Sudo K, Nakauchi H - J. Exp. Med. (2004)

Bottom Line: Assuming that a substantial portion of long-term repopulating cells can be detected as nmEM cells within this population, we compared differentiation potentials between individual pairs of daughter and granddaughter cells derived in vitro from single nmEM cells.The probability of asymmetric division of nmEM cells depended on the cytokines used.These data strongly suggest that lineage commitment takes place asymmetrically at the level of HSCs under the influence of external factors.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Stem Cell Therapy, Center for Experimental Medicine, Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, 108-8639, Japan.

ABSTRACT
How hematopoietic stem cells (HSCs) commit to a particular lineage is unclear. A high degree of HSC purification enabled us to address this issue at the clonal level. Single-cell transplantation studies revealed that 40% of the CD34-/low, c-Kit+, Sca-1+, and lineage marker- (CD34-KSL) cells in adult mouse bone marrow were able, as individual cells, to reconstitute myeloid and B- and T-lymphoid lineages over the long-term. Single-cell culture showed that >40% of CD34-KSL cells could form neutrophil (n)/macrophage (m)/erythroblast (E)/megakaryocyte (M) (nmEM) colonies. Assuming that a substantial portion of long-term repopulating cells can be detected as nmEM cells within this population, we compared differentiation potentials between individual pairs of daughter and granddaughter cells derived in vitro from single nmEM cells. One of the two daughter or granddaughter cells remained an nmEM cell. The other showed a variety of combinations of differentiation potential. In particular, an nmEM cell directly gave rise, after one cell division, to progenitor cells committed to nm, EM, or M lineages. The probability of asymmetric division of nmEM cells depended on the cytokines used. These data strongly suggest that lineage commitment takes place asymmetrically at the level of HSCs under the influence of external factors.

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Related in: MedlinePlus

Colony-forming ability of single CD34−KSL cells. CD34− KSL cells were individually cultured in the presence of SCF, IL-3, TPO, and EPO for 2 wk. Percentages of CFCs with different differentiation potentials are shown based on three independent experiments. Colony cells were morphologically identified as neutrophils (n), macrophages (m), erythroblasts (E), or megakaryocytes (M). Otherwise, unidentified immature cells were designated as blastlike cells (bl). The nmEM cells constituted 43.2 ± 3.2% (mean ± SD; n = 3) of the colony-forming CD34−KSL cells.
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fig2: Colony-forming ability of single CD34−KSL cells. CD34− KSL cells were individually cultured in the presence of SCF, IL-3, TPO, and EPO for 2 wk. Percentages of CFCs with different differentiation potentials are shown based on three independent experiments. Colony cells were morphologically identified as neutrophils (n), macrophages (m), erythroblasts (E), or megakaryocytes (M). Otherwise, unidentified immature cells were designated as blastlike cells (bl). The nmEM cells constituted 43.2 ± 3.2% (mean ± SD; n = 3) of the colony-forming CD34−KSL cells.

Mentions: Colony formation by single CD34−KSL cells was examined in the presence of a combination of SCF + IL-3 + TPO + EPO. On average, cells were not found in 2% of the wells due to sorting failure, immediate apoptosis, or adhesion of sorted cells to the wall of the plate. The differentiation potential could not be determined in 2–3% of the cells because they gave rise either to <50 cells or to as many as 1,000 cells with bl cell morphology. The remaining cells formed a variety of colonies as shown in Fig. 2. Approximately 40% of the colonies were classified as nmEM colonies; uni-, bi-, and tripotent progenitor cells were detected less frequently. On average, 98% of the nmEM colonies consisted of >104 cells (unpublished data), suggesting that these CFCs constitute a highly proliferative subset among CD34−KSL cells.


Asymmetric division and lineage commitment at the level of hematopoietic stem cells: inference from differentiation in daughter cell and granddaughter cell pairs.

Takano H, Ema H, Sudo K, Nakauchi H - J. Exp. Med. (2004)

Colony-forming ability of single CD34−KSL cells. CD34− KSL cells were individually cultured in the presence of SCF, IL-3, TPO, and EPO for 2 wk. Percentages of CFCs with different differentiation potentials are shown based on three independent experiments. Colony cells were morphologically identified as neutrophils (n), macrophages (m), erythroblasts (E), or megakaryocytes (M). Otherwise, unidentified immature cells were designated as blastlike cells (bl). The nmEM cells constituted 43.2 ± 3.2% (mean ± SD; n = 3) of the colony-forming CD34−KSL cells.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2211802&req=5

fig2: Colony-forming ability of single CD34−KSL cells. CD34− KSL cells were individually cultured in the presence of SCF, IL-3, TPO, and EPO for 2 wk. Percentages of CFCs with different differentiation potentials are shown based on three independent experiments. Colony cells were morphologically identified as neutrophils (n), macrophages (m), erythroblasts (E), or megakaryocytes (M). Otherwise, unidentified immature cells were designated as blastlike cells (bl). The nmEM cells constituted 43.2 ± 3.2% (mean ± SD; n = 3) of the colony-forming CD34−KSL cells.
Mentions: Colony formation by single CD34−KSL cells was examined in the presence of a combination of SCF + IL-3 + TPO + EPO. On average, cells were not found in 2% of the wells due to sorting failure, immediate apoptosis, or adhesion of sorted cells to the wall of the plate. The differentiation potential could not be determined in 2–3% of the cells because they gave rise either to <50 cells or to as many as 1,000 cells with bl cell morphology. The remaining cells formed a variety of colonies as shown in Fig. 2. Approximately 40% of the colonies were classified as nmEM colonies; uni-, bi-, and tripotent progenitor cells were detected less frequently. On average, 98% of the nmEM colonies consisted of >104 cells (unpublished data), suggesting that these CFCs constitute a highly proliferative subset among CD34−KSL cells.

Bottom Line: Assuming that a substantial portion of long-term repopulating cells can be detected as nmEM cells within this population, we compared differentiation potentials between individual pairs of daughter and granddaughter cells derived in vitro from single nmEM cells.The probability of asymmetric division of nmEM cells depended on the cytokines used.These data strongly suggest that lineage commitment takes place asymmetrically at the level of HSCs under the influence of external factors.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Stem Cell Therapy, Center for Experimental Medicine, Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, 108-8639, Japan.

ABSTRACT
How hematopoietic stem cells (HSCs) commit to a particular lineage is unclear. A high degree of HSC purification enabled us to address this issue at the clonal level. Single-cell transplantation studies revealed that 40% of the CD34-/low, c-Kit+, Sca-1+, and lineage marker- (CD34-KSL) cells in adult mouse bone marrow were able, as individual cells, to reconstitute myeloid and B- and T-lymphoid lineages over the long-term. Single-cell culture showed that >40% of CD34-KSL cells could form neutrophil (n)/macrophage (m)/erythroblast (E)/megakaryocyte (M) (nmEM) colonies. Assuming that a substantial portion of long-term repopulating cells can be detected as nmEM cells within this population, we compared differentiation potentials between individual pairs of daughter and granddaughter cells derived in vitro from single nmEM cells. One of the two daughter or granddaughter cells remained an nmEM cell. The other showed a variety of combinations of differentiation potential. In particular, an nmEM cell directly gave rise, after one cell division, to progenitor cells committed to nm, EM, or M lineages. The probability of asymmetric division of nmEM cells depended on the cytokines used. These data strongly suggest that lineage commitment takes place asymmetrically at the level of HSCs under the influence of external factors.

Show MeSH
Related in: MedlinePlus