Human Interleukin-12 Recombinant

IL-12 is secreted by peripheral lymphocytes after induction. It is produced mainly by B-cells and to a lesser extent by T-cells. The most powerful inducers of IL-12 are bacteria, bacterial products, and parasites. IL-12 is produced after stimulation with phorbol esters or calcium ionophore by human B-lymphoblastoid cells. The IL-12 receptor, CD212, appears to be a single protein of approximately 110 kDa. Up to 1000-9000 high affinity IL-12 receptors/cell are expressed on peripheral blood mononuclear cells activated by various mitogens for T-cells or by IL2. IL-12 receptors are present on activated T-cells expressing CD4 and CD8 and on activated CD56 (+) natural killer cells. Resting peripheral blood mononuclear cells, tonsillar B-cells, or tonsillar B-cells activated by anti-IgM/Dx, anti-IgM/Dx + IL-2, or SAC + IL-2 do not express the receptor. Human IL-12 is not active in murine lymphocytes. Hybrid heterodimers consisting of murine p35 and human p40 subunits retain bioactivity on murine cells, however, the combination of human p35 and murine p40 is completely inactive on murine cells. Murine IL-12 is active on both murine and human lymphocytes.

Reconstitute at 0.1-1.0 mg/ml in distilled water. This solution can then be diluted into other buffers. To maximize product collection from vial surface, vortex briefly and then spin down to recollect the liquid.

The lyophilized protein is stable for at least 2 years from date of receipt when stored at -20°C. Upon reconstitution, store in working aliquots at +4°C for up to one month, or at -20°C for up to six months, in the presence of a carrier protein. Avoid repeated freeze/thaw cycles.