Assessment of messenger RNA (mRNA) expression in CD34⁺ progenitors.

(A) Plots of real-time detection and amplification of mRNA of CXCR3 in freshly isolated and GM-CSF–stimulated CD34⁺ progenitors from human cord blood. Red plots represent the amplification of mRNA of CXCR3 in freshly isolated CD34⁺ progenitors; blue plots represent the amplification of CXCR3 mRNA of GM-CSF-stimulated CD34⁺ progenitors; and black plots represent the amplification of standard DNA template (2.0 × 10⁴copies) with a housekeeping gene (β-actin). C_Ts were 23.5 for standard DNA template; 30.1 for mRNA of CXCR3 in freshly isolated CD34⁺ progenitors; and 22.3 for mRNA of CXCR3 in GM-CSF–stimulated CD34⁺ progenitors. The plots shown are representative of 2 similar experiments conducted. (B) CXCR3 mRNA Northern blot analysis of freshly isolated and GM-CSF–stimulated CD34⁺ progenitors. Total RNA from different cells was isolated, electrophoresed, and blotted. The hybridization signals for CXCR3 mRNA from the cells are shown in the upper panel. Results with 28S recombinant RNAs (lower panel) confirmed that there were comparable amounts of loaded total RNA.