CD40 ligand is a 261 amino acid type II transmembrane glycoprotein belonging to the TNF family and can be cleaved into two chains: the CD40 ligand membrane form and CD40 ligand soluble form. It is primarily expressed on activated CD4+ T lymphocytes, and also found in other types of cells, like NK cells, mast cells, basophils and eosinophils. In total CD40 ligand has three binding partners: CD40, alpha5β1 integrin and alphaIIbβ3. It mediates a range of activities on B cells including induction of activation-associated surface antigen, entry into cell cycle, isotype switching and Ig secretion and memory generation. CD40-CD40L interaction also plays important roles in monocyte activation and dendritic cell maturation.
Source
Escherichia coli.
Molecular Weight
Approximately 16.3 kDa, a single non-glycosylated polypeptide chain containing 149 amino acids.
Biological Activity
Fully biologically active when compared to standard. The ED50 as determined by the dose-dependent stimulation of IL-8 production by human PBMC is less than 5-10 ng/ml.
Appearance
Sterile filtered white lyophilized (freeze-dried) powder.
Formulation
Lyophilized from a 0.2 um filtered concentrated solution in PBS, pH 7.0.
Endotoxin
Less than 1 EU/ug of rHusCD40L as determined by LAL method.
Reconstitution
We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1 % BSA to a concentration of 0.1-0.3 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20 °C. Further dilutions should be made in appropriate buffered solutions.
Stability and Storage
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.- 12 months from date of receipt, -20 to -70 °C as supplied.- 1 month, 2 to 8 °C under sterile conditions after reconstitution.- 3 months, -20 to -70 °C under sterile conditions after reconstitution.
