Description:
Interleukin 7 (IL-7), which is constitutively produced particularly by stromal cells from the bone marrow and thymus, plays a crucial role in T cell homeostasis. This cytokine is implicated in thymopoiesis since it sustains thymocyte proliferation and survival. It regulates peripheral naive T cell survival by modulating the expression of the anti-apoptotic molecule Bcl-2, and sustains peripheral T cell expansion in response to antigenic stimulation. Infection by the human immunodeficiency virus (HIV) leads to severe T lymphopenia and general immune dysfunction. Increased IL-7 plasma levels are generally observed in HIV-infected patients.
Recombinant Human IL-7 is a single, non-glycosylated polypeptide chain containing 172 amino acids and having a molecular mass of 17412 Dalton.
Human IL-7 is purified by proprietary chromatographic techniques.
Source:
Recombinant Human IL-7 produced in E.Coli
Physical Appearance:
Sterile Filtered White lyophilized (freeze-dried) powder.
Formulation:
Lyophilized from a concentrated (1mg/ml) solution in water containing no additives.
Solubility:
It is recommended to reconstitute the lyophilized rHuIL-7 in sterile 18Mω-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.
Soluble in water
Stability:
Lyophilized rHuIL-7 although stable at room temperature for 3 weeks, should be stored desiccated below -18 C. Upon reconstitution rHuIL-7 should be stored at 4 C between 2-7 days and for future use below -18 C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please avoid freeze-thaw cycles.
Purity:
Greater than 98.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Anion-exchange FPLC.
(c) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.
Amino Acid Sequence:
The sequence of the first five N-terminal amino acids was determined and was found to be Met-Asp-Cys-Asp-Ile.
Dimers and Aggregates:
Less than 1% as determined by silver-stained SDS-PAGE gel analysis and gel filtration.
Biological Activity:
PLR's rHuIL-7 is fully biologically active when compared to standard. The ED50 as determined by the dose-dependant stimulation of murine IXN/2B cells is less then 0.5ng/ml, corresponding to a Specific Activity of 2,000,000 IU/mg.
Endotoxin:
Less than 0.1 ng/µg (IEU/µg) of rHuIL-7.
Protein content:
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.
Usage:
PLR's products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.
