| Source: |
Escherichia coli. |
| Molecular Weight: |
Approximately 13.5 kDa, a single non-glycosylated polypeptide chain containing 121 amino acids. |
| AA Sequence: |
MHIHGCDKNH LREIIGILNE VTGEGTPCTE MDVPNVLTAT KNTTESELVC RASKVLRIFY LKHGKTPCLK KNSSVLMELQ RLFRAFRCLD SSISCTMNES KSTSLKDFLE SLKSIMQMDY S |
| Purity: |
> 97% by SDS-PAGE and HPLC analyses. |
| Biological Activity: |
Fully biologically active when compared to standard. The ED50 as determined by the dose-dependant prolifiration of Murine HT-2 cells is less then 2 ng/mL, corresponding to a Specific Activity of > 5 × 105 IU/mg. |
| Physical Appearance: |
Sterile filtered white lyophilized (freeze-dried) powder. |
| Formulation: |
Lyophilized from a 0.2 µm filtered solution in PBS, pH7.4. |
| Endotoxin: |
Less than 1 EU/µg of rMuIL-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: |
B-cell IgG differentiation factor, B-cell growth factor 1, BSF-1, IGG1 induction factor, Lymphocyte stimulatory factor 1 |
| Background: |
Interleukin-4 (IL-4), which prompts naive helper T cells (Th0 cells) to evolve into Th2 cells, is a multifunctional cytokine. This interleukin is produced by mast cells, activated T cells, and bone marrow stromal cells. The biological roles of IL-4 are wide-ranging, including stimulating the proliferation of activated B cells and T cells, and instigating the differentiation of CD4+ T cells into Th2 cells. Furthermore, IL-4 boosts the secretion and cell surface expression of IgE and IgG1, and modulates the expression of the low affinity Fc receptor for IgE (CD23) on lymphocytes and monocytes. Mouse IL-4 is composed of a single non-glycosylated polypeptide chain of 121 amino acid residues and has a compact, globular structure that is steadied by three disulfide bonds. The IL-4 in humans has approximately 40% amino acid sequence identity with mouse and rat IL-4 and their activities are specific to each species. |
