Synonyms
CD40-L, Tumor necrosis factor ligand superfamily member 5, TNF-related activation protein, TRAP, T cell antigen Gp39, CD154 antigen, sCD40, IGM, IMD3, HIGM1, T-BAM, TNFSF5, hCD40L.

Introduction
CD40L or CD154 is a membrane glycoprotein and differentiation antigen expressed on the surface of T-cells. The CD40 ligand stimulates B-cell proliferation and secretion of all immunoglobulin isotypes in the presence of cytokines . CD40 ligand has been shown to induce cytokine production and tumoricidal activity in peripheral blood monocytes. It also costimulates proliferation of activated T-cells and this is accompanied by the production of IFN-gamma , TNF-alpha , and IL2 .

Description
sCD40 Human Recombinant produced in E.Coli is a non-glycosylated, Polypeptide chain containing 149 amino acids and having a molecular mass of 16308 Dalton.
The sCD40 is purified by proprietary chromatographic techniques.

Source
Escherichia Coli.

Physical Appearance
Sterile Filtered White lyophilized (freeze-dried) powder.

Formulation
Lyophilized from a 0.2µm filtered concentrated (1mg/ml) solution in PBS, pH 7.0.

Solubility
It is recommended to reconstitute the lyophilized sCD40 in sterile 18M?-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.

Stability
Lyophilized sCD40 although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution CD154 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 prevent freeze-thaw cycles.

Purity

Greater than 97.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Analysis by SDS-PAGE.

Biological Activity
The ED50 as determined by the dose-dependant stimulation of IL-12 induction & IL-8 production by human PBMC was found to be 5-10 ng/ml.

Protein content
Protein quantitation was carried out by two independent methods:
1. UV spectroscopy at 280 nm using the absorbency value of 1.1 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 CD40 as a Reference Standard.