| Source: |
Escherichia coli. |
| Molecular Weight: |
Approximately 14.9 kDa, a single non-glycosylated polypeptide chain containing 129 amino acids. |
| AA Sequence: |
HNCHIALREI IETLNSLTEQ KTLCTKLTIT DILAASKNTT EKETFCRAAT VLRQFYSHHE KDTRCLGATA QQFHRHKQLI RFLKRLDRNL WGLAGLNSCP VKEANQSTLE DFLERLKTIM REKYSKCSS |
| Purity: |
> 96% 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 1.0 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 2 × PBS, pH7.4, 5% trehalose. |
| Endotoxin: |
Less than 1 EU/μg of rRhIL-4 as determined by LAL method. |
| Reconstitution: |
Centrifuge the vial briefly before opening to ensure that the contents settle at the bottom. Reconstitute the vial with sterile distilled water or an aqueous buffer containing 0.1% BSA to achieve 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. |
| Synonyms: |
BSF-1, Lymphocyte Stimulatory Factor 1 |
| Background: |
Interleukin-4 (IL-4), a versatile cytokine, is produced mainly by mast cells, activated T cells, and bone marrow stromal cells. It plays multiple roles, including stimulating the proliferation of activated B and T cells and differentiating CD4+ T cells into Th2 cells. IL-4 also enhances the secretion and expression of IgE and IgG1 and regulates the expression of the low-affinity Fc receptor for IgE on lymphocytes and monocytes. Rhesus macaque IL-4 shares about 40% to 45% amino acid sequence identity with human, mouse, and rat IL-4, and their activities are species-specific. |
