The sequence of the first five N-terminal amino acids was determined and was found to be Met-His-Lys-Cys-Asp.

The ED50 range= 1 to 4 ng/ml corresponding to a Specific Activity of 0.25-1MIU/mg. The biological activity is determined by measuring the dose dependent proliferation of human TF-1 cells. A concentration range of 0.1 to 10.0 ng/ml is effective for most in vitro applications.

Lyophilized from a concentrated (1mg/ml) solution in water containing no additives.

IL4 is a pleiotropic cytokine produced by activated T cells. IL4 is a ligand for interleukin 4 receptor. The interleukin 4 receptor also binds to IL13, which may contribute to many overlapping functions of this cytokine and IL13. STAT6, a signal transducer and activator of transcription, has been shown to play a central role in mediating the immune regulatory signal of this cytokine. This gene, IL3, IL5, IL13, and CSF2 form a cytokine gene cluster on chromosome 5q, with this gene particularly close to IL13. IL4, IL13 and IL5 are found to be regulated coordinately by several long-range regulatory elements in an over 120 kilobase range on the chromosome. Two alternatively spliced transcript variants of this gene encoding distinct isoforms have been reported.

Sterile Filtered White lyophilized (freeze-dried) powder.

Protein quantitation was carried out by two independent methods
1. UV spectroscopy at 280 nm using the absorbency value of 0.218 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).

2. Analysis by RP-HPLC, using a standard solution of IL-4 as a Reference Standard.

Greater than 95.0% as determined by(a) Analysis by RP-HPLC.
(b) Analysis by SDS-PAGE.

It is recommended to reconstitute the lyophilized Interleikin-4 in sterile 18MΩ-cm H2O not less than 100ug/ml, which can then be further diluted to other aqueous solutions.

Escherichia Coli.

Lyophilized Interleukin-4 although stable at room temperature for 3 weeks, should be stored desiccated below -18^oC. Upon reconstitution IL4 should be stored at 4^oC between 2-7 days and for future use below -18^oC.
Please avoid multiple freeze-thaw cycles.

Interleukin-4, BCGF, BCDF, B cell stimulating factor, BSF-1, Lymphocyte stimulatory factor 1, IL-4, MGC79402, Binetrakin, Pitrakinra.