Recombinant Human IL-4

This lyophilized preparation is stable at 2-8C. Upon receipt, store desiccated at -20C. After reconstitution, the preparation is stable for up to one week at 2-8C. For maximal stability, apportion the reconstituted preparation into working aliquots and store at -20C to -80C. For long term storage of reconstituted protein, it is recommended that a carrier protein such as 0.1% BSA or HSA be added. This depends on the particular application. Avoid repeated freeze/thaw cycles.

Interleukin-4 (IL-4) is a pleiotropic cytokine that induces differentiation of naive helper T cells (Th0 cells) to Th2 cells and produced by mast cells, activated T cells and bone marrow stromal cells. It has many biological roles, including the stimulation of activated B-cells 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 regulates the expression of the low affinity Fc receptor for IgE (CD23) on both lymphocytes and monocytes. Human IL-4 has a compact, globular structure, stabilized by 3 disulfide bonds. Human IL-4 shares about 40% aa sequence identity with mouse/rat IL-4, and each cytokine is species-specific in its activity. Recombinant Human Interleukin-4 is a single non-glycosylated polypeptide chain containing 129 amino acids.

Centrifuge vial prior to opening. Add sterile distilled water or aqueous buffer to a concentration of 0.1-1.0 mg/ml. Further dilutions should be made in appropriate buffered solutions.

Fully biologically active when compared to standard. The ED50 determined by a cell proliferation assay using human TF-1 cells is less than 0.2 ng/ml.