4-1BB Receptor (CD137) is a member of the TNF receptor superfamily expressed on activated CD4 and CD8 T cells as well as on activated natural killer cells. The binding of 4-1BB Receptor to its TNF family ligand, 4-1BB ligand (4-1BBL) delivers a co-stimulatory signal to resting T cells leading to high level IL2 production independently of CD28 signaling. Recombinant Human 4-1BB Receptor represents the soluble, cysteine-rich TNFR-like extracellular domain of 4-1BB Receptor.
The ED50 as determined by dose dependent proliferation of human megakaryocytic leukemia cell line is <0.5ng/ml.
Lyophilized from 0.2 ?m filtered solution in PBS (pH 7.5)
A quick spin of the vial followed by reconstitution in distilled water to a concentration not less than 0.1 mg/mL. This solution can then be diluted into other buffers.
>95% as determined by SDS-PAGE
< 1.0 EU/μg of recombinant protein as determined by the LAL method.
The lyophilized protein is stable for at least one year from date of receipt at -70?C. Upon reconstitution, this cytokine can be stored in working aliquots at 2? - 8?C for one month, or at -20?C for six months, with a carrier protein without detectable loss of activity.
Avoid repeated freeze/thaw cycles.