practical, the PAX samples showed a decrease in the number of expressed genes and lower gene expression values with higher variability compared to the PBMCs. Although whole blood samples contain more cell populations with different relative proportions than PBMCs, expression profile differences between the two isolation methods are also likely to be (partly) caused by the abundance of globin mRNA. Additional steps in the PAX protocol involving globin reduction could improve sensitivity and variability of this sample type relative to other isolation methods [8,22-27].
