INTENDED USE & DESCRIPTION
For use as quantitative controls for the determination of cytokine concentrations in biological fluids. Concentrations have been assigned using R&D Systems’ Quantikine® kits. Controls are prepared in a buffered protein solution with preservatives. They contain recombinant human cytokines at low, medium and high concentrations. Controls are supplied lyophilized.
STORAGE & STABILITY
Unreconstituted Controls should be stored at 2-8 °C and are stable for at least 6 months from date of receipt. Depending on the analyte of interest, reconstituted controls may be stable when stored at
REAGENT PREPARATION
Reconstitute each vial with the volume of deionized or distilled water indicated on the product datasheet.
PROCEDURE & EXPECTED VALUES
Controls should be assayed in the same manner as unknown specimens.
The acceptable ranges for the analytes in these controls are printed on the product datasheet. Due to possible variations in techniques and methodologies, it is recommended that each laboratory determine its own target range. Laboratories using other test systems should establish their own acceptable ranges as these assays may produce different values.
TECHNICAL HINTS & LIMITATIONS OF THE PROCEDURE
• The ranges were determined using R&D Systems’ Quantikine kits. If expected values are not obtained, verify that the lot numbers on the vials correspond with the lot numbers listed above and the correct volume of deionized or distilled water was used for reconstitution of the controls.
• The results obtained with these controls depend upon several factors associated with methods and instrumentation. Test systems other than those supplied by R&D Systems may result in values that differ from those printed on this product datasheet.
The human tissue kallikrein (KLK) gene family contains 15 members that play important roles in cancer. Notably, kallikrein-1, also known as tissue kallikrein, cleaves kininogen to release the vasoactive kinin peptide, bradykinin or lysyl-bradykinin. Kallikrein-3, called prostate specific antigen (PSA), is an established tumor marker that aids in the diagnosis, staging, and follow up of prostate cancer. Kallikrein-4 is specifically expressed in the prostate and over-expressed in prostate cancer. Kallikrein-5 is widely expressed but found at high levels in skin, breast, brain and testis; over-expression is an indicator of poor prognosis in ovarian cancer. Kallikrein-8 is expressed in the brain and is a novel marker of ovarian and cervical cancer.
Human plasma kallikrein, a serine protease, is synthesized in the liver and circulates in the plasma bound to high molecular weight (HMW) kininogen or as a free zymogen. Once activated by its physiological activator, coagulation factor XII, it displays endopeptidase activity towards peptide bonds after arginine (preferred) and lysine. It cleaves HMW kininogen, its major physiological substrate, to release the potent vasodilator peptide bradykinin. It is also able to cleave a number of inactive precursor proteins to generate active products, such as plasminogen and prourokinase.