Ciliary Neurotrophic Factor, Recombinant, Human (CNTF)
|Molecular Biology||Storage: -20°CShipping: RT|
A neurotrophic factor that promotes the survival of various neuronal cell types and may play an important role in the injury response in the nervous system. CNTF, like FGF acidic, FGF basic, and PD-ECGF (platelet-derived endothelial cell growth factor), does not possess a signal sequence that would allow secretion of the factor by classical secretion pathways (endoplasmatic reticulum/Golgi system). The mechanism underlying the release of CNTF is unknown.
Recombinant Human CNTF is a single, non-glycosylated polypeptide chain containing 199 amino acids and having a molecular mass of 22,706 Daltons.
The sequence of the first five N-terminal amino acids was determined and was found to be Met-Ala-Phe-Thr-Glu.
Dimers and Aggregates:
1% as determined by silver-stained SDS-PAGE gel analysis.
Protein quantitation was carried out by two independent methods:
1. UV spectroscopy at 280nm using the absorbency value of 1.28 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
2. Analysis by RP-HPLC, using a standard solution of human CNTF as a Reference Standard.
Recombinant Human Ciliary Neurotrophic Factor is fully biologically active when compared to standard. The ED50 as determined by the dose-dependent stimulation of TF-1 cells is less then 2 ng/ml, corresponding to a Specific Activity of 5 x 10 IU/mg.
Recommended to reconstitute the lyophilized CNTF in sterile 18M -cm H2O not less than 100ug/ml, which can then be further diluted to other aqueous solutions.
Storage and Stability:
Lyophilized powder may be stored at 4°C for short-term only. Reconstitute to nominal volume by adding sterile dH2O and store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial prior to removing the cap. Further dilutions can be made in assay buffer.
Source: E. coli
Purity: 98% by RP-HPLC, FPLC, or reducing/non-reducing SDS-PAGE Silver Stain. Chromatographically purified.
Form: Supplied as a lyophilized powder in 5mM sodium phosphate buffer, pH 7.5, 5mM sodium chloride.
Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.