by Gerald de Haan, Willem Nijhof, and Gary Van Zant Mouse Strain-Dependent Changes in Frequency and Proliferation of Hematopoietic Stem Cells During Aging: Correlation Between Lifespan and Cycling Activity by Gerald de Haan, Willem Nijhof, and Gary Van Zant Blood Volume 89(5):1543-1550 March 1, 1997 ©1997 by American Society of Hematology

Overview of the cobblestone area forming cell (CAFC) assay and its relationship with other stem/progenitor cell assays. Overview of the cobblestone area forming cell (CAFC) assay and its relationship with other stem/progenitor cell assays. The CAFC assay permits the dissection of the hierarchical, heterogeneous stem cell pool into several distinct subsets. Most essential is the fact that with increasing duration of the culture period, the primitiveness of the evaluated cell subsets increases correspondingly. Shown are the CAFC subsets, evaluated at weekly intervals, and their equivalents in other classic, functional or phenotypic stem cell assays. Evaluating the cultures for 35 days covers the major part of the hematopoietic stem cell hierarchy. The question mark on top of the figure indicates that it is still possible that even more primitive cells exist. If this is the case, it has no implications for the conclusions drawn in this study. Abbreviations: S, a stem cell that has multi-lineage potential; P, a progenitor cell that has restricted potential; LTRA, a cell which has long-term repopulating abilities; CFU-S, colony forming unit-spleen. Gerald de Haan et al. Blood 1997;89:1543-1550 ©1997 by American Society of Hematology

The correlation between the ratio of the numbers of CAFC day 7 to day 35, and the maximal lifespan of five mouse strains. The correlation between the ratio of the numbers of CAFC day 7 to day 35, and the maximal lifespan of five mouse strains. Individual data points, obtained from young (•) or old (▴) mice are shown. The regression shows the relationship with the maximal lifespan of the respective strains. Lifespans for C3H/He is 500 days, for CBA/J 512 days, for DBA/2 710 days, for BALB/c 745 days, and for C57BL/6 789 days. The values of the correlation coefficients “r” are given, in addition to the level of significance (p). Gerald de Haan et al. Blood 1997;89:1543-1550 ©1997 by American Society of Hematology

Frequency of CAFC subsets in old mice compared with their young counterparts. Frequency of CAFC subsets in old mice compared with their young counterparts. Mean frequencies of CAFC day 7, 14, 21, 28, and 35 in old C3H/He (•, 1 experiment, 5 mice), CBA/J (*, 3 experiments, 15 mice), DBA/2 (▴, 1 experiment, 5 mice), BALB/c (▪, 3 experiments, 15 mice), and C57BL/6 (♦, 2 experiments, 9 mice) mice. Data are expressed as percentage of CAFC values found in young mice. (A) The CAFC frequencies per 105 marrow cells; (B) values per femur. Control frequencies in young mice for each cell type per 105 marrow cells were: C3H/He: day 7: 124, day 14: 61, day 21: 7.54, day 28: 2.14, day 35: 0.65. CBA/J: day 7: 110, day 14: 31.4, day 21: 5.34, day 28: 1.40, day 35: 0.50. DBA/2: day 7: 125, day 14: 77, day 21: 13.4, day 28: 7.61, day 35: 1.55. BALB/c: day 7: 80, day 14: 50.4, day 21: 11.8, day 28: 2.74, day 35: 0.87. C57BL/6: day 7: 123, day 14: 18.5, day 21: 4.96, day 28: 2.61, day 35: 1.01. Control values for (B) can be calculated using these data and the data given in Table 1. Gerald de Haan et al. Blood 1997;89:1543-1550 ©1997 by American Society of Hematology

Frequencies of CAFC day 28 and 35 in young and old C3H/He, CBA/J, DBA/2, BALB/c, and C57BL/6 mice. Frequencies of CAFC day 28 and 35 in young and old C3H/He, CBA/J, DBA/2, BALB/c, and C57BL/6 mice. (A and B) The mean CAFC frequencies per 105 marrow cells; (C and D) mean numbers of CAFC per femur. For the number of mice per group refer to the legend of Fig 2. Strains are plotted in order of increasing maximal lifespan (indicated below X-axis). Gerald de Haan et al. Blood 1997;89:1543-1550 ©1997 by American Society of Hematology

Cycling activity of CAFC subsets in old and young mice. Cycling activity of CAFC subsets in old and young mice. Shown is the fraction of CAFC day 7 (A), 14 (B), 21 (C), and 28 (D), obtained from young (•) or old (▴) mice, that were killed by incubation, in vitro, with hydroxyurea (HU). The regression line, using individual data points obtained in young and old mice, shows the relationship with the maximal lifespan of the respective strains. Lifespans for C3H/He is 500 days, for CBA/J 512 days, for DBA/2 710 days, for BALB/c 745 days, and for C57BL/6 789 days. The correlation coefficient “r” of these lines is given in each figure, in addition to the level of significance (p). CAFC day 35 were not affected by HU (data are not shown). Gerald de Haan et al. Blood 1997;89:1543-1550 ©1997 by American Society of Hematology