Human LIF is a 19.7 kDa protein containing 181 amino acid residues. The non-glycosylated, E. coli expressed, recombinant human LIF is indistinguishable from native LIF in its biological activities in vitro. 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.
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.
Product Source: LIF 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 HPLC chromatography.
RECOMMENDED QC PROTOCOL
1. The M1 bioassay is performed using in vitro semi-solid agar cultures, which contain approximately 100 cells in 1 mL volumes of DME containing 20 % FCS in 0.3% agar.
2. Add 100 μL of sample or hLIF (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).
Visit www.esgro-lif.com for additional information
Manufactured by CHEMICON International, Inc. LIF is protected under US Patent nos. 5,443,825, 5,750,654 and 6,261,548, European Patent no. 0285 448 and related foreign patents and is not available for resale.
Specific Activity: where 50 units is defined as the amount of human LIF required to induce differentiation in 50% of the M1 colonies in 1 mL agar cultures.
Liquid in PBS, pH 7.4 and 0.02% Tween 20. No preservativies 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.
Manufactured by CHEMICON International, Inc. LIF is protected under US Patent nos. 5,187,077, 5,427,925, 5,443,825, 5,750,654 and 6,261,548, European Patent no. 0285 448 and related foreign patents and is not available for resale.
Specific Activity: The activity of human LIF is determined by the ability to induce differentiation of M1 myeloid leukemic cells.The minimum detectable concentration of human LIF in this assay is 0.5 ng/mL
Tested negative in both aseptic and microplasmic tests.
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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.
LABEL LICENSE - USE RESTRICTED TO RESEARCH USE ONLY
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.