The sequence of the first five N-terminal amino acids was determined and was found to be Asp-Cys-Asp-Ile-Glu.
The ED50 as determined by the dose-dependent stimulation of thymidine uptake by murine pre-B cell line 2E8 is < 0.5 ng/mL, corresponding to a specific activity of 2MU/mg.
Lyophilized from a concentrated (1mg/ml) solution in water containing 20mM phosphate buffer.
Sterile Filtered White lyophilized (freeze-dried) powder.
Protein quantitation was carried out by two independent methods
1. UV spectroscopy at 280 nm using the absorbency value of 0.418 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 IL-7 as a Reference Standard.
Greater than 98.0% as determined by SDS-PAGE.
It is recommended to reconstitute the lyophilized Interleukin -7 in sterile 18MΩ-cm H2O not less than 100ug/ml, which can then be further diluted to other aqueous solutions.
Saccharomyces cerevisiae.
Lyophilized Interleukin-7 although stable at room temperature for 3 weeks, should be stored desiccated below -18oC. Upon reconstitution IL7 should be stored at 4oC between 2-7 days and for future use below -18oC.
For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please avoid multiple freeze-thaw cycles.
Lymphopoietin 1 (LP-1), pre-B cell factor, IL-7.
