Type
Recombinant
Description
LIFisapleiotrophicfactorproducedbymultiplecelltypes,includingTcells,myelomonocyticlineages,fibroblasts,liver,heartandmelanoma.LIFpromoteslong-termmaintenanceofembryonicstemcellsbysuppressingspontaneousdifferentiation.Otheractivitiesincludethestimulationofacutephaseproteinsynthesisbyhepatocytes,stimulationofdifferentiationofcholinergicnerves,andsuppressionofADIpogenesisbyinhibitingthelipoproteinlipaseinadipocytes.WhilehumanLIFisactiveonmousecellsandiswidelyusedinthemaintenanceofmurineESCtopreventspontaneousdifferentiation,mouseLIFisnotactiveonhumancellsduetoitsinABIlitytobindtothehumanLIFreceptor.RecombinantHumanLIFisa19.6 kDaproteincontaining180 aminoacidsresidues,includingthreedisulfide bonds.
AminoAcidSequence
SPLPITPVNATCAIRHPCHNNLMNQIRSQLAQLNGSANALFILYYTAQGEPFPNNLDKLCGPNVTDFPPFHANGTEKAKLVELYRIVVYLGTSLGNITRDQKILNPSALSLHSKLNATADILRGLLSNVLCRLCSKYHVGHVDVTYGPDTSGKDVFQKKKLGCQLLGKYKQIIAVLAQAF
Source
E.coli
Purity
98%
BIOLOGicalActivity
DeterminedbyitsabilitytostimulatetheproliferationofhumanTF-1 cells.TheexpectedED50 is≤0.1 ng/ml,correspondingtoaspecificactivityof≥1×107 units/mg.
Endotoxin
Endotoxinlevelis<0.1 ng/μgofprotein(<1EU/μg).
Reconstitution
Centrifugethevialpriortoopening.Reconstituteinwatertoaconcentrationof0.1–1.0 mg/ml.Donotvortex.Forextendedstorage,itisrecommendedtofurtherdiluteinabuffercontainingacarrierprotein(example0.1%BSA)andstoreinworkingaliquotsat –20°Cto –80°C.
Storage/Expiration
–20°C