Stemfactor™ LIF, Human Recombinant

Recombinant Human LIF is a lymphoid factor that promotes long-term maintenance of the pluripotency of embryonic stem cells by suppressing spontaneous differentiation^1,2. Leukemia Inhibitory Factor (LIF) has additional functions such as cholinergic neuron differentiation, bone and fat metabolism, mitogenesis of certain factor dependent cell lines and promotion of megakaryocyte production in vivo³. Human LIF is an approximate 20 kDa protein containing 202 amino acid residues and is active on both human and mouse cells.

Stemgent and the Stemfactor brand name are trademarks of REPROCELL Inc., Japan.

Product Name: Stemfactor LIF, Human Recombinant

Catalog Number: 03-0016

Size: 1mL, 10µg/mL 1mL, 100µg/mL

Purity: Greater than 99% by SDS-PAGE analysis.

Formulation: LIF is supplied as a 0.22µm sterile filtered liquid in PBS containing 1% w/v BSA as carrier.

Storage and Stability: Store LIF at 4°C. Do not freeze. Stable for up to 6 months from date of receipt, when stored as directed.

Concentration: 1mL, 10µg/mL (Cat. No. 03-0016) 1mL, 100µg/mL (Cat. No. 03-0016-100)

Source: E. coli

Endotoxin Level: Less than 1 EU/µg of LIF as determined by the LAL method.

Biologic Activity: Human LIF activity is assessed by its ability to induce differentiation of M1 myeloid leukemia cells. The specific activity is 1 × 10⁶ units/mL (Cat. No. 03-0016) and 1 × 10⁷ units/mL (Cat. No. 03-0016-100), where 50 units is defined as the amount of human LIF required to induce differentiation in 50% of the M1 colonies in 1 mL of medium.

Specification Sheets:

• 03-0016 Specifications Sheet
• 03-0016-100 Specifications Sheet

Safety Data Sheets:

• 03-0016 and 03-0016-100 Safety Data Sheet

1. Williams, R.L., Hilton, D.J., Pease, S., Willson, T.A., Stewart, C.L., Gearing, D.P., Wagner, E.F., Metcalf, D., Nicola, N.A., and Gough, N.M. Myeloid leukemia inhibitory factor maintains the developmental potential of embryonic stem cells. Nature 336: 684-687(1988).
2. Gough, N.M., Gearing, D.P., King, J.A., Willson, T.A., Hilton, D.J., Nicola, N.A., and Metcalf, D. Molecular cloning and expression of the human homologue of the murine gene encoding myeloid leukemia-inhibitory factor. Proc Natl Acad Sci USA 85: 2623-2627(1988).
3. Hanna, J., Cheng, A.W., Saha, K., Kim, J., Lengner, C.J., Soldner, F., Cassady, J.P., Muffat, J., Carey, B.W., and Jaenisch, R. (2010) Human embryonic stem cells with biological and epigenetic characteristics similar to those of mouse ESCs. Proc Natl Acad Sci USA 107: 9222-9227(2010).

Additional Publications

• Metcalf D. The unsolved enigmas of leukemia inhibitory factor. Stem Cells 21: 5-14 (2003).