Leukemia Inhibitory Factor (LIF) human, a 20kD protein containing 181aa residues, is a multifunctional gylcoprotein that induces macrophage differentiation and supresses the proliferation of the M1 myeloid cell line. Synonyms for LIF include: differentiation-inhibitory activity (DIA) for murine embryonic stem (ES) cells, human interleukin for DA cells (HLDA), hepatocyte stimulation factor III, cholinergic neuronal differentiation factor and lipoprotein lipase inhibitor. Leukemia Inhibitory Factor plays an important role, along with Interleukin-6 (IL-6) and granulocyte-colony stimulating factor (G-CSF), in the regulation of early hematopoietic stem cells. LIF is also important in the release of calcium from bone tissue. Human LIF is active on human and mouse cells, whereas mouse LIF is active on mouse cells. There is a 78% homology between mouse and human.
Activity:The biological activity of recombinant human LIF is measured by its ability to stimulate the differentiation of the M1 mouse myeloid leukemic cell line. The specific activity is ≥1x10e8 units/mg, where 50 units is defined as the amount of mouse LIF required to induce differentiation in 50% of the M1 colonies in 1ml agar cultures.
Storage and Stability:May be stored at 4°C. For long-term storage, aliquot and store at 4°C. Do not freeze. Aliquots are stable for 6 months. For maximum recovery of product, centrifuge the original vial prior to removing the cap. Further dilutions can be made in PBS, 1% BSA or 0.02% Tween 20.
