||Recombinant Human LIF produced inE. coliis a single, non-glycosylated, polypeptide chain containing 180 amino acids and having a molecular mass of 19.717 kDa.
||Leukemia Inhibitory Factor (LIF), a 20kDa protein, is a lymphoid factor which promotes long-term maintenance of embryonic stem cells by suppressing spontaneous differentiation. LIF has a number of other activities including cholinergic neuron differentiation, control of stem cell pluripotency, bone and fat metabolism, mitogenesis of certain factor dependent cell lines and promotion of megakaryocyte production in vivo. Human and murine mature LIF exhibit a 78% sequence identity at the amino acid control. Human LIF is equally active on both human and mouse cells. Murine LIF is approximately 1000 fold less active on human cells, than hLIF.
||>95% by SDS-PAGE, RP-HPLC and FPLC.
||Lyophilized after extensive dialysis against PBS.
||The ED50 was determined by the M1 cell differentiation assay is < 0.01 ng/ml, corresponding to a specific activity of 1.0 x 108IU/mg.
||Less than 0.1ng/µg (1IEU/µg) of LIF.
||We recommend a quick spin followed by reconstitution in water to a concentration of 0.1-1.0mg/ml. It is recommended that further dilutions be made into buffer or medium to which protein (e.g., 1% BSA) or Tween 20 has been added. This solution can then be stored at 4°C for 1 week or -20°C for future use.
||Lyophilized rHuLIF although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution rHuLIF should be stored at 4°C between 2-7 days and for future use below -18°C. For long-term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Aliquot to avoid repeated freeze-thaw cycles.