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Leukemia Inhibitory Factor from mouse

50 µg, mouse recombinant LIF protein, expressed in E. coli, suitable for stem cell culture

LIF, Differentiation-stimulating Factor, D Factor

biological source


Quality Level


>95% (SDS-PAGE)



specific activity

≥1 x 10(E8) U/mg




100 μg/mL


cell culture | stem cell: suitable


<0.1 ng/mg Endotoxin (of LIF)


sample type: mouse embryonic stem cell(s)
sample type neural stem cell(s)
sample type induced pluripotent stem cell(s)
sample type hematopoietic stem cell(s)
sample type mesenchymal stem cell(s)

NCBI accession no.

UniProt accession no.

shipped in

wet ice

General description

Leukemia Inhibitory Factor (LIF) 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. Mouse LIF is a 22 kDa protein containing 203 amino acid residues.
Product Source: mLIF is expressed in E. coli as a fusion protein with GST using the pGEX expression system, cleaved from GST moeity with thrombin and purified by multiple FPLC steps.


50 µg, mouse recombinant LIF protein, expressed in E. coli, suitable for stem cell culture

M1 Bioassay

1. The M1 bioassay is performed using in vitro semi-solid agar cultures, which contain approximately 300 cells in 1 mL volumes of DME containing 20 % FCS in 0.3% agar.

2. Add 100 μL of sample or mLIF (10(E4) units/mL in 5% FCS in isotonic saline) in two-fold serial dilutions in duplicate to 35 mm petri dishes.

3. Add 100 μL of 5% FCS in isotonic saline to two control slides.

4. Incubate at 37°C in fully humidified atmosphere of 10% CO2 in air for 7 days.

5. Score the number of colonies that show differentiation (note: 50 units is defined as the amount of activity which results in 50% of the colonies being differentiated).
Research Category
Stem Cell Research

Unit Definition

Specific Activity: where 50 units is defined as the amount of mouse LIF required to induce differentiation in 50% of the M1 colonies in 1 mL agar cultures.

Physical form

Liquid in PBS, pH 7.4 and 0.02% Tween 20. No preservatives added.

Storage and Stability

Maintain at 2-8°C for 6-12 months. Further dilutions should be made into buffer or medium to which protein (e.g., 1% BSA) or Tween 20 has been added.

Analysis Note

Specific Activity: The activity of mouse LIF is determined by the ability to induce differentiation of murine M1 myeloid leukemic cells.The minimum detectable concentration of mouse LIF in this assay is 0.5 ng/mL
Tested negative in both aseptic and mycoplasmic tests.

Legal Information

CHEMICON is a registered trademark of Merck KGaA, Darmstadt, Germany


Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.


Leukemia Inhibitory Factor ("LIF") is protected by US Patents No. 5,443,825 and 5,750,654 and Canada Patent No. 1,341,581 and 1,341,469 owned by AMRAD Corporation Ltd. and licensed exclusively to Millipore for research uses. The use of this product is limited for research uses only and not for any commercial purposes, such as making or developing other research products from this product or use of this product as a component in a research kit. This product is not to be used in humans or for any diagnostic purposes.

The purchaser may refuse to accept the conditions of this label license by returning this product unopened and will receive a full refund of the purchase price paid.

For-profit entities or commercial research entities purchasing this product shall be required to execute a separate commercial license with Millipore within three months of purchase. Researchers may not transfer this product or its derivatives to researchers performing commercial research at other Nonprofit Organizations, or to For-Profit Organizations, without the express written consent of Millipore, and without those entities having an express license from Millipore for the use of the product. Other than as specifically provided herein, a transferee of this product shall have no right to transfer this product, or its derivatives to any other person or entity.

Storage Class Code

12 - Non Combustible Liquids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

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Certificate of Quality

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