| Source: |
Escherichia coli. |
| Molecular Weight: |
Approximately 12.5 kDa, a single non-glycosylated polypeptide chain containing 112 amino acids. |
| AA Sequence: |
GPVPPSTALR ELIEELVNIT QNQKAPLCNG SMVWSINLTA GMYCAALESL INVSGCSAIE KTQRMLSGFC PHKVSAGQFS SLHVRDTKIE VAQFVKDLLL HLKKLFREGR FN |
| Purity: |
> 97% by SDS-PAGE and HPLC analyses. |
| Biological Activity: |
Fully biologically active when compared to standard. The ED50 as determined by a cell proliferation assay using human TF-1 cells is less than 1 ng/mL, corresponding to a specific activity of > 1.0 × 106 IU/mg. |
| Physical Appearance: |
Sterile filtered white lyophilized (freeze-dried) powder. |
| Formulation: |
Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH7.4 with 5% trehalose. |
| Endotoxin: |
Less than 1 EU/µg of rHuIL-13 as determined by LAL method. |
| Reconstitution: |
Centrifuge the vial briefly before opening to ensure that the contents settle at the bottom. Reconstitute in 20 mM HCl to a concentration of 0.1-1.0 mg/mL. Divide the resulting stock solution into working aliquots and store them at or below -20°C. For further dilutions, use appropriate buffered solutions. |
| Stability & 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. |
| Background: |
Human Interleukin-13 (IL-13), encoded by the IL13 gene on chromosome 5, is predominantly produced by Th2 cells. Its structure is characterized by two internal disulfide bonds forming a four α-helix bundle. IL-13 plays a crucial role in Th2 cell development and in defending against gastrointestinal parasites. It also moderates inflammation by reducing the production of certain cytokines by monocytes and macrophages, and it promotes B cell proliferation and IgE production. Despite low homology, IL-13 from humans, mice, and rats exhibits cross-species functionality. |
