The biological effects of interleukin 2 (IL-2) are mediated by its binding to a multi-chain cellular receptor complex. The IL-2 receptor (IL-2 R) complex consists of three glycoprotein chains. The alpha chain (IL-2 R alpha /CD25) and beta chain (IL-2 R beta /CD122) act together with the gamma chain (IL-2 R gamma /CD132) to form a high affinity receptor that transduces the signal upon IL-2 binding. Alone, IL-2 R alpha binds IL-2 with low affinity, but is unable to transduce a signal. The alpha/beta combination binds IL-2 with intermediate affinity, but is still unable to transmit a signal inside the cell. The beta/gamma complex has intermediate affinity and is capable of signaling if the concentration of IL-2 is relatively high. A soluble form of IL-2 R alpha is present in the serum in parallel with its increased cellular expression. There are reports of soluble IL-2 R beta as well. The biologic function of soluble IL-2 R alpha is unclear because, due to its low affinity, it is expected to be a poor inhibitor of IL-2. IL-2 R alpha is a precursor type I membrane protein with a signal peptide, an extracellular region, a transmembrane region, and a cytoplasmic domain. Studies suggest a correlation between the levels of IL-2 R alpha in serum with the onset of rejection in allograft recipients, with autoimmune disease activation in rheumatoid arthritis and systemic lupus erythematosis patients and with the course of some leukemias and lymphomas.
Sample Type:Cell culture supernates, serum, EDTA plasma, and heparin plasma.
Sensitivity:The mean MDD was 0.45pg/ml. The Minimum Detectable Dose (MDD) was determined by adding two standard deviations to the MFI of twenty zero standard replicates and calculating the corresponding concentration.
Range:~0.24-0.76pg/ml
Specificity:Recognizes natural and recombinant human IL-2 Ra.
Test Principle:Human IL-2 R alpha BioAssay™ Kit afford the user the benefit of multianalyte analysis of biomarkers in a complex sample. For each sample type, a single, multipurpose diluent is used to optimize recovery, linearity, and reproducibility. Such a multipurpose diluent may not optimize any single analyte to the same degree that a unique diluent selected for analysis of that analyte can optimize conditions. Therefore, some performance characteristics may be more variable than those for assays designed specifically for single analyte analysis.
Storage and Stability:Store powder at 4°C. Store other components at 4°C. Stable for at least 6 months For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
