Recombinant Human Interleukin-16 (IL16)
(Cat. No.: C045)

Background:
    IL-16 is a CD8+ T cell-derived cytokine that induces chemotaxis of CD4+ T cells and CD4+ monocytes and eosinophils. Analysis by gel filtration suggests that, under physiological conditions, human IL-16 exists predominantly as a noncovalently linked multimer, but that some IL-16 may exist as a monomer. However, only the multimeric form appears to possess chemotactic activity, suggesting that receptor cross-linking may be required for activity. IL-16 also induces expression of IL-2 receptor (IL-2R) and MHC class II molecules on CD4+ T cells. Human and murine IL-16 show significant cross-species reactivity

Description:
    Recombinant Human IL-16 produced in E. coli is a single, non-glycosylated polypeptide chain containing 130 amino acids and having a molecular mass of 13.4 kDa.

Quality Control:
    Biological activity: rHuIL-16 is fully biologically active when compared to standard. The ED50 as determined by its ability to chemoattract human CD4+ T lymphocytes using a concentration range of 10.0-100.0 ng/ml, corresponding to a Specific Activity greater than 1.0 x 104 IU/mg.
    Purity:
Greater than 97.0% as determined by:
        (a) Analysis by RP-HPLC.
        (b) Anion-exchange FPLC.
        (c) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.
    Amino-Acid Sequence: The sequence of the first five N-terminal amino acids was determined and was found to be Met-Pro-Asp-Leu-Asn.
    Endotoxin: Less than 0.1ng/µg (1 IEU/µg) determined by LAL test.

Formulation:
   
rHuIL-16 was lyophilized from 1mg/ml solution after extensive dialysis against 20 mM acetic buffer, pH 5.0, 150 mM NaCl and 0.5 mM DTT.

Storage:
   
Lyophilized rHuIL-16 although stable at room temperature for 3 weeks, should be stored desiccated below -18¡ãC. Upon reconstitution rHuIL-16 should be stored at 4¡ãC between 2-7 days and for future use below -18¡ãC. For long-term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please avoid freeze-thaw cycles.

Reconstitution:
   
It is recommended to reconstitute the lyophilized rHuIL-16 in sterile 18M¦¸-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.