Amphiregulin is an EGF related growth factor and was originally isolated from the conditioned media of a PMA-treated MCF-7 human breast carcinoma cell line. It is mainly expressed numerous carcinoma cell lines and the epithelial cells of various human tissues including colon, stomach, breast, ovary, kidney, etc. Synthesized as a transmembrane protein, Amphiregulin’s extracellular domain is proteolytically processed to release the mature protein. There are 6 conserved cysteine residues, which form 3 intramolecular disulfide bonds essential for biological activity. Amphiregulin signals through the EGF/TGF-a receptor, and stimulates growth of keratinocytes, epithelial cells and some fibroblasts. It also inhibits the growth of certain carcinoma cell lines. Mutations in this encoded protein are associated with a psoriasis-like skin phenotype.
Source
Escherichia coli.
Molecular Weight
Approximately 11.3 kDa, a single non-glycosylated polypeptide chain containing 98 amino acid residues.
Biological Activity
Fully biologically active when compared to standard. The ED50 as determined by a cell proliferation assay using murine Balb/c 3T3 cells is between 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 7.4.
Endotoxin
Less than 1 EU/ug of rHuAmphiregulin 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 0.1-1.0 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.