|Synonyms||BSF-1, Binetrakin, Lymphocyte stimulatory factor 1, Pitrakinra.|
|Molecular Weight||Approximately 15.0 kDa, a single non-glycosylated polypeptide chain containing 129 amino acids.|
|AA Sequence||HKCDITLQEI IKTLNSLTEQ KTLCTELTVT DIFAASKNTT EKETFCRAAT VLRQFYSHHE KDTRCLGATA QQFHRHKQLI RFLKRLDRNL WGLAGLNSCP VKEANQSTLE NFLERLKTIM REKYSKCSS|
|Purity||> 98 % 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 0.2 ng/ml, corresponding to a specific activity of > 5.0 × 106 IU/mg.|
|Physical Appearance||Sterile Filtered White lyophilized (freeze-dried) powder.|
|Formulation||Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH 7.4.|
|Endotoxin||Less than 1.0 EU/µg of rHuIL-4 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 & 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.
|Usage||This material is offered by Shanghai PrimeGene Bio-Tech for research, laboratory or further evaluation purposes. NOT FOR HUMAN USE.|
|Reference||1. Sokol CL, Barton GM, Farr AG, et al. 2008. Nat Immunol. 9:310-8.|
2. Hershey GK, Friedrich MF, Esswein LA, et al. 1997. N Engl J Med. 337:1720-5.
3. Yokota T, Otsuka T, Mosmann T, et al. 1986. Proc Natl Acad Sci U S A. 83:5894-8.
4. Eder A, Krafft-Czepa H, Krammer PH. 1988. Nucleic Acids Res. 16:772.
5. Walter MR, Cook WJ, Zhao BG, et al. 1992. J Biol Chem. 267:20371-6.
|Background||Interleukin-4 (IL-4) is a pleiotropic cytokine that induces differentiation of naive helper T cells (Th0 cells) to Th2 cells and produced by by mast cells, activated T cells and bone marrow stromal cells. It has many biological roles, including the stimulation of activated B-cell and T-cell proliferation, and the differentiation of CD4+ T-cells into Th2 cells. In addition, It enhances both secretion and cell surface expression of IgE and IgG1 and also regulates the expression of the low affinity Fc receptor for IgE (CD23) on both lymphocytes and monocytes. The human IL-4 has a compact, globular fold, stabilised by 3 disulphide bonds. The human IL-4 shares about 40% aa sequence identity with mouse/rat IL-4 and they are species-specific in their activities.|