ORP-3 gene expression as measured by Taqman real-time PCR.

All gene expression results are calculated relative to β-actin and are expressed in arbitrary units (mean ± SEM).24Wilcoxon signed-rank test was used to determine the statistical significance of the differences between related groups for nonparametric data. (A) ORP-3 gene expression in CD34⁺ (▪) and CD34⁻ (░) hematopoietic cells from UCB (6.3 ± 0.9, 2.0 ± 0.4, n = 21,*P ≤ .0001) and ABM (11.2 ± 2.2, 2.6 ± 1.1, n = 14, #P ≤ .001). Mean purity of the UCB and ABM CD34⁺-enriched populations were 57.5% ± 2.8% and 55.0% ± 4.8%, respectively. The percentage of CD34⁺ cells in the CD34⁻ fractions was less than 0.01%. Average viability of the CD34⁺ and CD34⁻ populations (more than 95%) did not vary significantly. ORP-3 gene expression did not correlate with sample purity (results not shown). (B) ORP-3 gene expression in CD34⁻ (░), CD34⁺ (▪), and CD34⁺ cells after 1-week culture (■) from UCB (6.2 ± 0.9, 2.5 ± 0.6, n = 14, *P ≤ .01) and ABM (10.8 ± 3.5, 3.6 ± 1.1, n = 9, #P ≤ .01). FACS analysis of the CD34⁺ and CD34^+culture samples showed that after 1-week culture under the conditions described, the percentage of CD34⁺ cells decreased by approximately 33%. Total cell number increased by approximately 10%, and viability of the 2 populations (more than 90%) did not vary significantly. (C)ORP-3 gene expression in UCB CD34⁻(2.0 ± 0.5), CD34⁺CD38⁺ (8.0 ± 2.9), and CD34⁺CD38⁻ hematopoietic cells (17.6 ± 3.8, n = 5, P ≤ .04). CD34⁺38^−/dullcells were sorted using sort gates constructed to include approximately 10% of the total CD34⁺ population. Viability (greater than 80%) of the 2 populations did not vary significantly.