Abstract: A hemopoietic stem cell augmenting agent in which at least one type of hepatocyte growth factor is contained as an active component is provided. The hepatocyte growth factor has an augmenting activity on undifferentiated pluripotent hemopoietic stem cells and is useful as a hemopoietic stem cell augmenting agent for treatment of bone marrow suppression and for treatment of bone marrow malfunctions and furthermore is useful for in vitro growth of peripheral blood stem cells and bone marrow stem cells. Furthermore, a hepatocyte growth factor derived from human normal fibroblasts which is considered to be a type of hepatocyte growth factor can be obtained by genetic recombination techniques, and said factor is also useful as a hemopoietic stem cells augmenting agent.

Abstract: An 18 kDa protein, denominated FDF-3, has been isolated from cultures of human fibroblasts and has been found to potentiate the growth- and differentiation-promoting activities of certain cytokines toward hematopoietic progenitor cells. The amino acid sequence of the FDF-3 protein, shown in SEQ ID NO: 14, corresponds to the sequence of a C-terminal domain of human fibronectin. The protein is useful in combination with IL-3, G-CSF, GM-CSF, or SCF (stem cell factor) in the expansion of hematopoietic cell populations in vitro or in therapeutic methods to promote recovery from leukopenia or myelosuppresion in vivo.