Aging hematopoietic progenitor/stem cells

To determine how aging impacts gene expression in hematopoietic stem cells (HSCs), human CD34+ cells from bone marrow (34BM) and mobilized stem cell products (34P38NPBSC) were examined using microarray-based expression profiling. Differential expression changes were confirmed by microarray comparisons of younger and older expanded T-cell populations. We compared gene expression profiles between younger and older human CD34+ cells from bone marrow (34BM) and CD34+CD38- cells from mobilized stem cell products(34P38NPBSC). We also examined gene expression changes associated with aging in human expanded T-cells. For 34BM and T-cells, biotin-labeling of total RNA (5 µg) was performed as per standard Affymetrix protocol. For the 34P38NPBSC arrays, the single-stranded linear amplification protocol was used to process total RNA (100 nanograms) for the microarrays. Both protocols are described in detail in PMID14706461.