Fully biologically active when compared to standard. The specific activity is determined by inducing differentiation of murine M1 myeloid leukemic cells. The minimum detectable concentration of rMuLIF in this assay is 0.01ng/ml. The specific activity of >1.0×108IU/mg, where 50 units is defined as the amount of rMuLIF required to induce differentiation in 50% of the M1 colonies in 1ml agar cultures.
Physical Appearance
Sterile Filtered White lyophilized (freeze-dried) powder.
Formulation
Lyophilized from a 0.2μM filtered concentrated solution in 20mM PB, pH7.4, with 0.02% TWEEN 20.
Endotoxin
Less than 1EU/μg of rMuLIF as determined by LAL method.
Reconstitution
We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0mg/ml. Stock solutions should be apportioned into working aliquots and stored at ≤-20℃. Further dilutions should be made in appropriate buffered solutions.
Category
Cytokine
Background
Leukemia inhibitory factor (LIF) is a member of Interleukin 6 family. This protein is mainly expressed in the trophectoderm of the developing embryo, with its receptor LIFR expressed throughout the inner cell mass. LIF has the capacity to induce terminal differentiation in leukemic cells. Its activities include the induction of hematopoietic differentiation in normal and myeloid leukemia cells, the induction of neuronal cell differentiation, and the stimulation of acute-phase protein synthesis in hepatocytes. LIF is used in mouse embryonic stem cell culture, because that removal of LIF pushes stem cells toward differentiation, but they retain their proliferative potential or pluripotency. It is also used in phase II clinical trial, which can assist embryo implantation in women who have failed to become pregnant despite assisted reproductive technologies (ART). Mature mouse LIF shares 78%a.a. sequence identity with Human LIF.
