Angiopoietin-like proteins stimulate ex vivo expansion of hematopoietic stem cells. Mus musculus

Successful ex vivo expansion of hematopoietic stem cells (HSCs) would greatly benefit the treatment of disease and the understanding of critical questions of stem cell biology. Microarray studies showed that the HSC supportive mouse fetal liver CD3+ cells specifically expressed angiopoietin-like 2 (Angptl2) and angiopoietin-like 3 (Angptl3). When highly enriched HSCs were cultured in the presence of Angptl2 or Angptl3 together with saturating levels of other growth factors for 10 days, a 24 or 30 fold net expansion of long-term HSCs was observed by reconstitution analysis. The coiled-coil domain of Angptl2 mediated the effects of Angptl2 on HSC expansion. Furthermore, angiopoietin-like 5, angiopoietin-like 7, and microfibril-associated glycoprotein 4 also supported expansion of HSCs in culture. Keywords: Cell type comparison Overall design: Cultured 3 different cell types -> Total RNA isolation -> dscDNA -> Biotinylated cRNA -> hybridization to Affymetrix U74Bv2 and U74Cv2 mouse chips