Macrophage inflammatory protein-1 alpha (MIP-1 alpha) and leukemia inhibitory factor (LIF) protect the repopulating ability of purified murine hematopoietic stem cells in serum-deprived cultures stimulated with SCF and IL-3

The engraftment potential of murine stem cells (HSC) is greatly reduced when these cells are expanded in vitro with stem cell factor and interleukin-3. We have evaluated if the addition of MIP-1 alpha or LIF to these cultures would protect the ability of murine wild type HSC to engraft the stem cell defective W/Wv recipient. In this transplantation model red and white blood cell reconstitution is assessed by hemoglobin electrophoresis and c-kit PCR genotyping, respectively. The results obtained indicate that both MIP-1 alpha and LIF protect, at least transiently, the HSC repopulating ability in vivo in spite of the modest expansion in the number of nucleated and progenitor cells observed.