These properties of angiogenin are reflected by enhanced hematopoietic regeneration and animal survival upon treatment with recombinant angiogenin protein following radiation-induced bone marrow failure and a dramatic increase in the level of hematopoietic reconstitution by angiogenin-treated mouse LT-HSCs (long-term HSCs) and human CD34+ cord blood cells (11,35). Here, CD34 is linked to Bone marrow hypocellularity.