Highly abundant genes in the transcriptosome of human and baboon CD34 antigen-positive bone marrow cells

Nonhuman primates are useful large animal model systems for the in vivo stu dy of hematopoietic stem cell biology. To better understand the degree of s imilarity of the hematopoietic systems between humans and baboons, and to e xplore the relevance of such studies in nonhuman primates to humans, this s tudy Was designed to compare the global gene expression profile of bone mar row CD34(+) cells isolated from these 2 species. Human complementary DNA (c DNA) filter arrays containing 25 920 human cDNAs were surveyed for this pur pose, The expression pattern and relative gene abundance of the 2 RNA sourc es were similar, with a correlation coefficient of 0.87, A total of 15 970 of these cDNAs were expressed in human CD34(+) cells, of which the majority (96%) varied less than 3-fold in their relative level of expression betwee n human and baboon. Reverse transcriptase-polymerase chain reaction analysi s of selected genes confirmed that expression was comparable between the 2 species. No species-restricted transcripts have been identified, further re inforcing the high degree of similarity between the 2 populations. A subset of 1554 cDNAs, which are expressed at levels 100-fold and greater than bac kground, is described, which includes 959 expressed sequence tags and uncha racterized cDNAs, and 595 named genes, including many that are clearly invo lved in hematopoiesis, The cDNAs reported here represent a selection of som e of the most highly abundant genes in hematopoietic cells and provide a st arting point to develop a profile of the transcriptosome of CD34(+) cells. (C) 2001 by The American Society of Hematology.