Interleukin-4 (IL-4) is a pleiotropic cytokine mainly produced 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. Additionally, 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 rhesus macaque IL-4 shares about 40 % ~ 45 % a.a. sequence identity with human, mouse, rat IL-4 and they are species-specific in their activities.
来历
Escherichia coli.
份子量
Approximately 14.9 kDa, a single non-glycosylated polypeptide chain containing 129 amino acids.
生物活性
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.
表面
Sterile filtered white lyophilized (freeze-dried) powder.
配方
Lyophilized from a 0.2 um filtered concentrated solution in 2 × PBS, pH 7.4, 5 % trehalose.
内毒素
Less than 1 EU/ug of rRhIL-4 as determined by LAL method.
消融申明
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.
贮存前提
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.