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Recombinant human LIF protein (Qk036)
Human LIF (leukemia inhibitory factor) protein suppresses the differentiation of murine embryonic stem cells (ESCs) and is widely used in ESC and iPSC culture.1
Qkine human LIF protein is high purity and animal and carrier-protein free for reproducible results.
Orders are typically shipped same or next day (except Friday).
Easy world-wide ordering, direct or through our distributors.
1000µg will be despatched as 2 x 500µg
Buy online with secure credit card or purchase order or email orders@qkine.com
Bulk and stock reservation available
Summary
High purity human LIF protein (Uniprot: P15018)
>98%, by SDS-PAGE quantitative densitometry
17 kDa
Expressed in E. coli.
Animal-free (AOF) and carrier protein-free.
Manufactured in our Cambridge, UK laboratories
Lyophilized from acetonitrile, TFA
Resuspend in 10mM HCl at >100 µg/ml, prepare single use aliquots, add carrier protein if desired and store frozen at -20°C or -80°C
Featured applications
Propagation of ES cells in feeder or feeder-free chemically defined culture systems
Human LIF can be used in the maintenance of murine ESCs
Human
Species similarity:
Bovine – 88%
Porcine – 87%
Rat – 83%
Mouse – 78%
Frequently used together
Bioactivity
Human LIF activity is determined using the LIF-responsive firefly luciferase reporter assay. HEK293T cells are treated in triplicate with a serial dilution of LIF overnight. Firefly luciferase activity is measured and normalised to the control Renilla luciferase activity.
EC50 = 16.8 pM (0.29 ng/mL).
Data from Qk036 lot #104293.
Purity
Human LIF protein (Qk036) migrates as a single band at 20 kDa in non-reducing (NR) and upon reduction (R)
Purified recombinant human LIF protein (3 μg) was resolved using 15% w/v SDS-PAGE in reduced (+β-mercaptoethanol, R) and non-reduced conditions (NR) and stained with Coomassie Brilliant Blue R250. Data from Qk036 lot #104293.
Further quality assays
Mass spectrometry: single species with expected mass
Analytical reversed-phase: single sharp peak
Endotoxin: <0.005 EU/μg protein (below level of detection)
Recovery from stock vial >95%
We are a company founded and run by scientists to support innovation in stem cell biology and regenerative medicine. To enhance reliability and reproducibility in your applications, all our products are exceptionally high purity, with complete characterisation and bioactivity analysis on every lot.
Protein background
LIF is a pleiotrophic factor that belongs to the IL-6 superfamily of cytokines. Acting through a heterodimeric receptor of LIFR (gp190) and gp130, LIF activates a number of cellular pathways including the JAK/STAT, PI3K and MAPK pathways.2 LIF signalling is essential for maintenance of murine pluripotency.1 Human LIF can be used for the maintenance of mouse embryonic stem cells, however mouse LIF cannot bind to the human receptor, thus rendering mouse LIF inactive on human cells.3
Publications
Nat Commun. 2024
Self-renewing human naïve pluripotent stem cells dedifferentiate in 3D culture and form blastoids spontaneously
Authors: Guo, M., Wu, J., Chen, C. et al.
Labs: José Silva, Guangzhou Laboratory
Preprint. 2024
Metabolic rewiring underpins human trophoblast induction
Authors: Jan Żylicz, Karlien van Nerum, Anne Wenzel, Lidia Argemi Muntadas, et al.
Lab: Jan Żylicz, University of Copenhagen, Denmark
Our products are for research use only and not for diagnostic or therapeutic use. Products are not for resale.
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