Figure 1. Effect of age on gene expression profiling in unactivated human peripheral blood CD4+ T lymphocytes. Total RNA isolated from CD4+ T cells that had been incubated for 4h at 37°C was converted to biotin labeled cRNA and hybridized to Illumina HumanRef-8 Expression BeadChip. Normalized hybridization data was analyzed using Parametric Analysis of Gene Set Enrichment (PAGE) (Broad Institute, M.I.T., Cambridge MA). (A) a set of 31 donors with age range 25-81 (