Characterization of the NK cell and DC potential of 2 separate intermediate CD34^lo precursors, CD44^hi or CD44^lo, derived from the earliest intrathymic progenitors.

(A) Representative cell size (forward scatter, FS) and flow cytometry profile (shaded monoparametric histograms) of sorted CD44^hi (CD5^lo) and CD44^lo(CD5⁺) intermediate CD34^lo progenitors (biparametric plots) derived by day 3.5 from CD34^hiCD33^lo precursors set up in multicytokine-supported cultures. Background fluorescence determined with isotype-matched irrelevant MoAbs is shown (unshaded histograms). Absolute numbers of total viable cells (B), DCs (CD7^loCD13⁺CD1a⁺) (C), and NK cells (CD7⁺⁺CD13⁻CD56⁺) (D) recovered from either CD44^hi (▴) or CD44^lo (●) intermediate CD34^lo progenitors derived in vitro and sorted as shown in (A), upon reculture in IL-2–supplemented multicytokine-supported conditions. Absolute numbers are referred to 10⁵ input progenitors. Results are presented as the mean of 5 independent experiments.