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Age-associated characteristics of murine hematopoietic stem cells.

Sudo K, Ema H, Morita Y, Nakauchi H - J. Exp. Med. (2000)

Bottom Line: Little is known of age-associated functional changes in hematopoietic stem cells (HSCs).They did not form day 12 colony-forming unit (CFU)-S, indicating that they are primitive cells with myeloid differentiation potential.We propose that HSCs gradually accumulate with age, accompanied by cells with less lymphoid differentiation potential, as a result of repeated self-renewal of HSCs.

View Article: PubMed Central - PubMed

Affiliation: Department of Immunology, Institute of Basic Medical Sciences, University of Tsukuba and Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tsukuba, Japan.

ABSTRACT
Little is known of age-associated functional changes in hematopoietic stem cells (HSCs). We studied aging HSCs at the clonal level by isolating CD34(-/low)c-Kit(+)Sca-1(+) lineage marker-negative (CD34(-)KSL) cells from the bone marrow of C57BL/6 mice. A population of CD34(-)KSL cells gradually expanded as age increased. Regardless of age, these cells formed in vitro colonies with stem cell factor and interleukin (IL)-3 but not with IL-3 alone. They did not form day 12 colony-forming unit (CFU)-S, indicating that they are primitive cells with myeloid differentiation potential. An in vivo limiting dilution assay revealed that numbers of multilineage repopulating cells increased twofold from 2 to 18 mo of age within a population of CD34(-)KSL cells as well as among unseparated bone marrow cells. In addition, we detected another compartment of repopulating cells, which differed from HSCs, among CD34(-)KSL cells of 18-mo-old mice. These repopulating cells showed less differentiation potential toward lymphoid cells but retained self-renewal potential, as suggested by secondary transplantation. We propose that HSCs gradually accumulate with age, accompanied by cells with less lymphoid differentiation potential, as a result of repeated self-renewal of HSCs.

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Limiting dilution analysis based on competitive repopulation. Varying numbers of bone marrow cells from either 2- or 18-mo-old mice were mixed with 2 × 105 bone marrow cells from 2-mo-old mice and injected into lethally irradiated mice. Reconstitution in myeloid and B and T lymphoid lineages was evaluated 12 wk after transplantation. Mice were considered to be negative when percent chimerism for myeloid or B or T lymphoid lineage was <1.0. 1 in 3.2 × 104 cells and 1 in 1.6 × 104 cells was a multilineage repopulating cell for 2-mo-old (▪) and 18-mo-old (•) mice. When uni- and bilineage repopulating cells were included in estimations of frequencies, 1 in 1.0 × 104 cells was a repopulating cell in 18-mo-old mice (○).
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Figure 1: Limiting dilution analysis based on competitive repopulation. Varying numbers of bone marrow cells from either 2- or 18-mo-old mice were mixed with 2 × 105 bone marrow cells from 2-mo-old mice and injected into lethally irradiated mice. Reconstitution in myeloid and B and T lymphoid lineages was evaluated 12 wk after transplantation. Mice were considered to be negative when percent chimerism for myeloid or B or T lymphoid lineage was <1.0. 1 in 3.2 × 104 cells and 1 in 1.6 × 104 cells was a multilineage repopulating cell for 2-mo-old (▪) and 18-mo-old (•) mice. When uni- and bilineage repopulating cells were included in estimations of frequencies, 1 in 1.0 × 104 cells was a repopulating cell in 18-mo-old mice (○).

Mentions: The percentages of negative mice in a logarithmic function were plotted against the number of cells transplanted (Fig. 1). According to the Poisson distribution, the frequency of competitive repopulating units 15 was estimated using the maximum likelihood 1819. 1 in 1.6 × 104 bone marrow cells was a multilineage repopulating cell in aging mice, whereas in young mice, 1 in 3.2 × 104 cells was such as a cell. As there was no significant difference in total numbers of nucleated bone marrow cells between 2 and 18 mo of age (Table ), it was concluded that the number of HSCs increased twofold from 2 to 18 mo of age.


Age-associated characteristics of murine hematopoietic stem cells.

Sudo K, Ema H, Morita Y, Nakauchi H - J. Exp. Med. (2000)

Limiting dilution analysis based on competitive repopulation. Varying numbers of bone marrow cells from either 2- or 18-mo-old mice were mixed with 2 × 105 bone marrow cells from 2-mo-old mice and injected into lethally irradiated mice. Reconstitution in myeloid and B and T lymphoid lineages was evaluated 12 wk after transplantation. Mice were considered to be negative when percent chimerism for myeloid or B or T lymphoid lineage was <1.0. 1 in 3.2 × 104 cells and 1 in 1.6 × 104 cells was a multilineage repopulating cell for 2-mo-old (▪) and 18-mo-old (•) mice. When uni- and bilineage repopulating cells were included in estimations of frequencies, 1 in 1.0 × 104 cells was a repopulating cell in 18-mo-old mice (○).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2193349&req=5

Figure 1: Limiting dilution analysis based on competitive repopulation. Varying numbers of bone marrow cells from either 2- or 18-mo-old mice were mixed with 2 × 105 bone marrow cells from 2-mo-old mice and injected into lethally irradiated mice. Reconstitution in myeloid and B and T lymphoid lineages was evaluated 12 wk after transplantation. Mice were considered to be negative when percent chimerism for myeloid or B or T lymphoid lineage was <1.0. 1 in 3.2 × 104 cells and 1 in 1.6 × 104 cells was a multilineage repopulating cell for 2-mo-old (▪) and 18-mo-old (•) mice. When uni- and bilineage repopulating cells were included in estimations of frequencies, 1 in 1.0 × 104 cells was a repopulating cell in 18-mo-old mice (○).
Mentions: The percentages of negative mice in a logarithmic function were plotted against the number of cells transplanted (Fig. 1). According to the Poisson distribution, the frequency of competitive repopulating units 15 was estimated using the maximum likelihood 1819. 1 in 1.6 × 104 bone marrow cells was a multilineage repopulating cell in aging mice, whereas in young mice, 1 in 3.2 × 104 cells was such as a cell. As there was no significant difference in total numbers of nucleated bone marrow cells between 2 and 18 mo of age (Table ), it was concluded that the number of HSCs increased twofold from 2 to 18 mo of age.

Bottom Line: Little is known of age-associated functional changes in hematopoietic stem cells (HSCs).They did not form day 12 colony-forming unit (CFU)-S, indicating that they are primitive cells with myeloid differentiation potential.We propose that HSCs gradually accumulate with age, accompanied by cells with less lymphoid differentiation potential, as a result of repeated self-renewal of HSCs.

View Article: PubMed Central - PubMed

Affiliation: Department of Immunology, Institute of Basic Medical Sciences, University of Tsukuba and Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tsukuba, Japan.

ABSTRACT
Little is known of age-associated functional changes in hematopoietic stem cells (HSCs). We studied aging HSCs at the clonal level by isolating CD34(-/low)c-Kit(+)Sca-1(+) lineage marker-negative (CD34(-)KSL) cells from the bone marrow of C57BL/6 mice. A population of CD34(-)KSL cells gradually expanded as age increased. Regardless of age, these cells formed in vitro colonies with stem cell factor and interleukin (IL)-3 but not with IL-3 alone. They did not form day 12 colony-forming unit (CFU)-S, indicating that they are primitive cells with myeloid differentiation potential. An in vivo limiting dilution assay revealed that numbers of multilineage repopulating cells increased twofold from 2 to 18 mo of age within a population of CD34(-)KSL cells as well as among unseparated bone marrow cells. In addition, we detected another compartment of repopulating cells, which differed from HSCs, among CD34(-)KSL cells of 18-mo-old mice. These repopulating cells showed less differentiation potential toward lymphoid cells but retained self-renewal potential, as suggested by secondary transplantation. We propose that HSCs gradually accumulate with age, accompanied by cells with less lymphoid differentiation potential, as a result of repeated self-renewal of HSCs.

Show MeSH