ESGRO^® Recombinant Mouse LIF Protein

Mouse Leukemia Inhibitory Factor (LIF, mLIF) promotes self-renewal and long-term maintenance of pluripotent mouse embryonic stem (ES) and induced pluripotent stem (iPS) cells by suppressing spontaneous differentiation.

The ESGRO mouse LIF medium supplement is supplied in active units/mL for consistent performance from lot to lot. Each lot of ESGRO supplement undergoes stringent quality control testing to ensure reliable inhibition of mouse pluripotent stem cell differentiation. ESGRO mouse LIF supplement may be used for feeder based and feeder free culture of mouse embryonic stem (ES) and induced pluripotent stem (iPS) cells.

Applications for ESGRO Supplement include use as a reagent for the in vitro maintenance of the pluripotential phenotype of murine ES cells.

SUGGESTED PROTOCOLS:

ES Cells: In D3 and MBL-1 pluripotential ES cell cultures it is routinely found that 1000 U ESGRO Supplement per 1.0 mL of tissue culture media is required to maintain ES cells with a stem cell phenotype. Similar concentrations of mLIF have also been used for germline transmission of genetically altered ES cells(E3).

At the recommended concentration 10⁷ units of ESGRO is sufficient for 10.0 L of tissue culture media and 10⁶ units of ESGRO Supplement is sufficient for 1.0 L of tissue culture media.

ESGRO Supplement is supplied in liquid form as 10⁷ Units in 1.0 mL of phosphate buffered saline with 1% w/v bovine serum albumin BSA as a carrier for stability.

Format: Purified

ESGRO^® Supplement is supplied 0.22 micron sterile filtered, and tested negative in mycoplasma tests.

ESGRO Supplement is shipped at ambient temperature. A cold pack may be included for customer relations, however it is truly not needed. Extensive stability tests have been performed with ESGRO Supplement during development. This product is stable for at least 18 months from the date of manufacture, in the concentrated form or diluted in sterile tissue culture media, with no loss of activity on ES cells. For long term storage it is recommended that ESGRO Supplement be stored at 4°C. Freeze-thawing will reduce potency. It is recommended that prior to use, ESGRO Supplement should be diluted in sterile tissue culture media and aliquoted to a convenient concentration, then stored at 4°C. Freeze-thawing should be avoided. Product is stable for a minimum of 7 days at 37°C, 5% CO2 incubator during the culture of ES cells.

Specific Activity: ESGRO^® Supplement is assessed both on mouse embryonic stem cells (D3 & MBL-1) and on murine M1 myeloid leukemic cells(4). A standard of 50 Units is defined as the concentration of ESGRO Supplement, in 1.0mL of tissue culture medium, that induces the differentiation of 50% of M1 colonies(4). 10E7 units is equivalent to approximately 100 μg of pure protein, and is sufficient to treat 10L of ES cell culture media.

Embryonic Stem Cell Assay: Differentiation inhibition at 1000 units/mL Murine myeloid leukemic, M1 Assay: Specific Activity >/= 10⁸ units/mg

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

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