Percentage of donor-derived chimerism of cell cycle subfractions.

Percentage of donor-derived chimerism at 6 months posttransplantation in mice receiving G₀/G₁ or S/G₂+M subfractions of total Sca-1⁺lin⁻ cells (▪), Sca-1⁺lin⁻ CD11a⁻ cells (■), Sca-1⁺lin⁻ CD49d^dim cells (●), or Sca-1⁺lin⁻ CD49e⁺ cells (○). Total Sca-1⁺lin⁻ cells or CD11a⁻, CD49d^dim, or CD49e⁺ subfractions of Sca-1⁺lin⁻ cells were isolated by cell sorting and then subfractionated by means of Hoechst 33342 into G₀/G₁ or S/G₂+M fractions. Between 0.4 to 1.0 × 10³ sorted donor cells from B6.BoyJ mice were transplanted into lethally irradiated C57BL/6 mice along with 1.0 × 10⁵ C57BL/6 competitor cells. Chimerism was monitored monthly by CD45.2 analysis of peripheral white blood cells. Purity of sorted donor G₀/G₁ cells was greater than 97%; purity of donor S/G₂+M cells was greater than 82%. Data points are values for the percentage of chimerism for individual mice; horizontal bars are mean chimerism levels. n = 10 for G₀/G₁ mice, n = 12 for S/G₂+M mice. *The presence of statistical significance between mice transplanted with G₀/G₁ and S/G₂+M fractions of engrafting phenotypes; P < .005.